kernel - Fix races created by a comedy of circumstansces (3)

[dragonfly.git] / sys / vfs / ntfs / ntfs_vnops.c

/*      $NetBSD: ntfs_vnops.c,v 1.23 1999/10/31 19:45:27 jdolecek Exp $ */

/*
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * John Heidemann of the UCLA Ficus project.
 *
 * 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 * $FreeBSD: src/sys/ntfs/ntfs_vnops.c,v 1.9.2.4 2002/08/06 19:35:18 semenu Exp $
 *
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <sys/buf.h>
#include <sys/dirent.h>
#include <machine/limits.h>

#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_page.h>
#include <vm/vm_object.h>
#include <vm/vm_pager.h>
#include <vm/vnode_pager.h>
#include <vm/vm_extern.h>

#include <sys/sysctl.h>

#include <sys/buf2.h>

#include "ntfs.h"
#include "ntfs_inode.h"
#include "ntfs_subr.h"

#include <sys/unistd.h> /* for pathconf(2) constants */

static int      ntfs_read (struct vop_read_args *);
static int      ntfs_write (struct vop_write_args *ap);
static int      ntfs_getattr (struct vop_getattr_args *ap);
static int      ntfs_inactive (struct vop_inactive_args *ap);
static int      ntfs_print (struct vop_print_args *ap);
static int      ntfs_reclaim (struct vop_reclaim_args *ap);
static int      ntfs_strategy (struct vop_strategy_args *ap);
static int      ntfs_access (struct vop_access_args *ap);
static int      ntfs_open (struct vop_open_args *ap);
static int      ntfs_close (struct vop_close_args *ap);
static int      ntfs_readdir (struct vop_readdir_args *ap);
static int      ntfs_lookup (struct vop_old_lookup_args *ap);
static int      ntfs_bmap (struct vop_bmap_args *ap);
static int      ntfs_fsync (struct vop_fsync_args *ap);
static int      ntfs_pathconf (struct vop_pathconf_args *);

int     ntfs_prtactive = 1;     /* 1 => print out reclaim of active vnodes */

/*
 * This is a noop, simply returning what one has been given.
 *
 * ntfs_bmap(struct vnode *a_vp, off_t a_loffset,
 *           daddr_t *a_doffsetp, int *a_runp, int *a_runb)
 */
int
ntfs_bmap(struct vop_bmap_args *ap)
{
        dprintf(("ntfs_bmap: vn: %p, blk: %u\n", ap->a_vp,
                (u_int32_t)ap->a_loffset));
        if (ap->a_doffsetp != NULL)
                *ap->a_doffsetp = ap->a_loffset;
        if (ap->a_runp != NULL)
                *ap->a_runp = 0;
        if (ap->a_runb != NULL)
                *ap->a_runb = 0;
        return (0);
}

/*
 * ntfs_read(struct vnode *a_vp, struct uio *a_uio, int a_ioflag,
 *           struct ucred *a_cred)
 */
static int
ntfs_read(struct vop_read_args *ap)
{
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct uio *uio = ap->a_uio;
        struct ntfsmount *ntmp = ip->i_mp;
        struct buf *bp;
        daddr_t cn;
        int resid, off, toread;
        int error;

        dprintf(("ntfs_read: ino: %ju, off: %u resid: %zd, segflg: %d\n",
                (uintmax_t)ip->i_number, (uint32_t)uio->uio_offset,
                uio->uio_resid, uio->uio_segflg));

        dprintf(("ntfs_read: filesize: %ju", (uintmax_t)fp->f_size));

        /* don't allow reading after end of file */
        if (uio->uio_offset > fp->f_size)
                return (0);

        resid = (int)szmin(uio->uio_resid, fp->f_size - uio->uio_offset);

        dprintf((", resid: %d\n", resid));

        error = 0;
        while (resid) {
                cn = ntfs_btocn(uio->uio_offset);
                off = ntfs_btocnoff(uio->uio_offset);

                toread = min(off + resid, ntfs_cntob(1));

                error = bread(vp, ntfs_cntodoff(cn), ntfs_cntob(1), &bp);
                if (error) {
                        brelse(bp);
                        break;
                }

                error = uiomovebp(bp, bp->b_data + off, toread - off, uio);
                if(error) {
                        brelse(bp);
                        break;
                }
                brelse(bp);

                resid -= toread - off;
        }

        return (error);
}

/*
 * ntfs_getattr(struct vnode *a_vp, struct vattr *a_vap)
 */
static int
ntfs_getattr(struct vop_getattr_args *ap)
{
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct vattr *vap = ap->a_vap;

        dprintf(("ntfs_getattr: %ju, flags: %d\n", (uintmax_t)ip->i_number,
                ip->i_flag));

        vap->va_fsid = dev2udev(ip->i_dev);
        vap->va_fileid = ip->i_number;
        vap->va_mode = ip->i_mp->ntm_mode;
        vap->va_nlink = ip->i_nlink;
        vap->va_uid = ip->i_mp->ntm_uid;
        vap->va_gid = ip->i_mp->ntm_gid;
        vap->va_rmajor = VNOVAL;
        vap->va_rminor = VNOVAL;
        vap->va_size = fp->f_size;
        vap->va_bytes = fp->f_allocated;
        vap->va_atime = ntfs_nttimetounix(fp->f_times.t_access);
        vap->va_mtime = ntfs_nttimetounix(fp->f_times.t_write);
        vap->va_ctime = ntfs_nttimetounix(fp->f_times.t_create);
        vap->va_flags = ip->i_flag;
        vap->va_gen = 0;
        vap->va_blocksize = ip->i_mp->ntm_spc * ip->i_mp->ntm_bps;
        vap->va_type = vp->v_type;
        vap->va_filerev = 0;
        return (0);
}


/*
 * Last reference to an ntnode.  If necessary, write or delete it.
 *
 * ntfs_inactive(struct vnode *a_vp)
 */
int
ntfs_inactive(struct vop_inactive_args *ap)
{
        struct vnode *vp = ap->a_vp;
#ifdef NTFS_DEBUG
        struct ntnode *ip = VTONT(vp);
#endif

        dprintf(("ntfs_inactive: vnode: %p, ntnode: %ju\n", vp, (uintmax_t)ip->i_number));

        if (ntfs_prtactive && VREFCNT(vp) > 1)
                vprint("ntfs_inactive: pushing active", vp);

        /*
         * XXX since we don't support any filesystem changes
         * right now, nothing more needs to be done
         */
        return (0);
}

/*
 * Reclaim an fnode/ntnode so that it can be used for other purposes.
 *
 * ntfs_reclaim(struct vnode *a_vp)
 */
int
ntfs_reclaim(struct vop_reclaim_args *ap)
{
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        int error;

        dprintf(("ntfs_reclaim: vnode: %p, ntnode: %ju\n", vp, (uintmax_t)ip->i_number));

        if (ntfs_prtactive && VREFCNT(vp) > 1)
                vprint("ntfs_reclaim: pushing active", vp);

        if ((error = ntfs_ntget(ip)) != 0)
                return (error);
        
        ntfs_frele(fp);
        ntfs_ntput(ip);
        vp->v_data = NULL;

        return (0);
}

/*
 * ntfs_print(struct vnode *a_vp)
 */
static int
ntfs_print(struct vop_print_args *ap)
{
        return (0);
}

/*
 * Calculate the logical to physical mapping if not done already,
 * then call the device strategy routine.
 *
 * ntfs_strategy(struct vnode *a_vp, struct bio *a_bio)
 */
int
ntfs_strategy(struct vop_strategy_args *ap)
{
        struct bio *bio = ap->a_bio;
        struct buf *bp = bio->bio_buf;
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct ntfsmount *ntmp = ip->i_mp;
        u_int32_t toread;
        u_int32_t towrite;
        size_t tmp;
        int error;

        dprintf(("ntfs_strategy: loffset: %u, doffset: %u\n",
                (uint32_t)bp->b_loffset, (uint32_t)bio->bio_offset));

        dprintf(("strategy: bcount: %u flags: 0x%x\n",
                bp->b_bcount, bp->b_flags));

        bp->b_error = 0;

        switch(bp->b_cmd) {
        case BUF_CMD_READ:
                if (bio->bio_offset >= fp->f_size) {
                        clrbuf(bp);
                        error = 0;
                } else {
                        toread = min(bp->b_bcount,
                                 fp->f_size - bio->bio_offset);
                        dprintf(("ntfs_strategy: toread: %u, fsize: %ju\n",
                                toread, (uintmax_t)fp->f_size));

                        error = ntfs_readattr(ntmp, ip, fp->f_attrtype,
                                fp->f_attrname, bio->bio_offset,
                                toread, bp->b_data, NULL);

                        if (error) {
                                kprintf("ntfs_strategy: ntfs_readattr failed\n");
                                bp->b_error = error;
                                bp->b_flags |= B_ERROR;
                        }

                        bzero(bp->b_data + toread, bp->b_bcount - toread);
                }
                break;
        case BUF_CMD_WRITE:
                if (bio->bio_offset + bp->b_bcount >= fp->f_size) {
                        kprintf("ntfs_strategy: CAN'T EXTEND FILE\n");
                        bp->b_error = error = EFBIG;
                        bp->b_flags |= B_ERROR;
                } else {
                        towrite = min(bp->b_bcount,
                                      fp->f_size - bio->bio_offset);
                        dprintf(("ntfs_strategy: towrite: %d, fsize: %ju\n",
                                towrite, (uintmax_t)fp->f_size));

                        error = ntfs_writeattr_plain(ntmp, ip, fp->f_attrtype,  
                                fp->f_attrname, bio->bio_offset,towrite,
                                bp->b_data, &tmp, NULL);

                        if (error) {
                                kprintf("ntfs_strategy: ntfs_writeattr fail\n");
                                bp->b_error = error;
                                bp->b_flags |= B_ERROR;
                        }
                }
                break;
        default:
                panic("ntfs: bad b_cmd %d", bp->b_cmd);
        }
        biodone(bio);
        return (error);
}

/*
 * ntfs_write(struct vnode *a_vp, struct uio *a_uio, int a_ioflag,
 *            struct ucred *a_cred)
 */
static int
ntfs_write(struct vop_write_args *ap)
{
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct uio *uio = ap->a_uio;
        struct ntfsmount *ntmp = ip->i_mp;
        size_t towrite;
        size_t written;
        int error;

        dprintf(("ntfs_write: ino: %ju, off: %u resid: %zd, segflg: %d\n",
                (uintmax_t)ip->i_number, (uint32_t)uio->uio_offset,
                uio->uio_resid, uio->uio_segflg));
        dprintf(("ntfs_write: filesize: %ju ", (uintmax_t)fp->f_size));

        if (uio->uio_resid + uio->uio_offset > fp->f_size) {
                kprintf("ntfs_write: CAN'T WRITE BEYOND END OF FILE\n");
                return (EFBIG);
        }
        if (uio->uio_offset > fp->f_size)
                return (EFBIG);

        towrite = szmin(uio->uio_resid, fp->f_size - uio->uio_offset);

        dprintf((", towrite: %zd\n", towrite));

        error = ntfs_writeattr_plain(ntmp, ip, fp->f_attrtype,
                fp->f_attrname, uio->uio_offset, towrite, NULL, &written, uio);
#ifdef NTFS_DEBUG
        if (error)
                kprintf("ntfs_write: ntfs_writeattr failed: %d\n", error);
#endif

        return (error);
}

/*
 * ntfs_access(struct vnode *a_vp, int a_mode, struct ucred *a_cred)
 */
int
ntfs_access(struct vop_access_args *ap)
{
        struct vnode *vp = ap->a_vp;
        struct ntnode *ip = VTONT(vp);
        struct ucred *cred = ap->a_cred;
        mode_t mask, mode = ap->a_mode;
        gid_t *gp;
        int i;
#ifdef QUOTA
        int error;
#endif

        dprintf(("ntfs_access: %ju\n", (uintmax_t)ip->i_number));

        /*
         * Disallow write attempts on read-only file systems;
         * unless the file is a socket, fifo, or a block or
         * character device resident on the file system.
         */
        if (mode & VWRITE) {
                switch ((int)vp->v_type) {
                case VDIR:
                case VLNK:
                case VREG:
                        if (vp->v_mount->mnt_flag & MNT_RDONLY)
                                return (EROFS);
#ifdef QUOTA
                        if (error = getinoquota(ip))
                                return (error);
#endif
                        break;
                }
        }

        /* Otherwise, user id 0 always gets access. */
        if (cred->cr_uid == 0)
                return (0);

        mask = 0;

        /* Otherwise, check the owner. */
        if (cred->cr_uid == ip->i_mp->ntm_uid) {
                if (mode & VEXEC)
                        mask |= S_IXUSR;
                if (mode & VREAD)
                        mask |= S_IRUSR;
                if (mode & VWRITE)
                        mask |= S_IWUSR;
                return ((ip->i_mp->ntm_mode & mask) == mask ? 0 : EACCES);
        }

        /* Otherwise, check the groups. */
        for (i = 0, gp = cred->cr_groups; i < cred->cr_ngroups; i++, gp++)
                if (ip->i_mp->ntm_gid == *gp) {
                        if (mode & VEXEC)
                                mask |= S_IXGRP;
                        if (mode & VREAD)
                                mask |= S_IRGRP;
                        if (mode & VWRITE)
                                mask |= S_IWGRP;
                        return ((ip->i_mp->ntm_mode&mask) == mask ? 0 : EACCES);
                }

        /* Otherwise, check everyone else. */
        if (mode & VEXEC)
                mask |= S_IXOTH;
        if (mode & VREAD)
                mask |= S_IROTH;
        if (mode & VWRITE)
                mask |= S_IWOTH;
        return ((ip->i_mp->ntm_mode & mask) == mask ? 0 : EACCES);
}

/*
 * Open called.
 *
 * Nothing to do.
 *
 * ntfs_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred,
 *           struct file *a_fp)
 */
/* ARGSUSED */
static int
ntfs_open(struct vop_open_args *ap)
{
        return (vop_stdopen(ap));
}

/*
 * Close called.
 *
 * Update the times on the inode.
 *
 * ntfs_close(struct vnode *a_vp, int a_fflag)
 */
/* ARGSUSED */
static int
ntfs_close(struct vop_close_args *ap)
{
#if NTFS_DEBUG
        struct vnode *vp = ap->a_vp;
        struct ntnode *ip = VTONT(vp);

        kprintf("ntfs_close: %ju\n", (uintmax_t)ip->i_number);
#endif

        return (vop_stdclose(ap));
}

/*
 * ntfs_readdir(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred,
 *              int *a_ncookies, off_t **cookies)
 */
int
ntfs_readdir(struct vop_readdir_args *ap)
{
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct uio *uio = ap->a_uio;
        struct ntfsmount *ntmp = ip->i_mp;
        int i, j, error = 0;
        wchar c;
        u_int32_t faked = 0, num, off;
        int ncookies = 0;
        char convname[NTFS_MAXFILENAME + 1];

        dprintf(("ntfs_readdir %ju off: %u resid: %zd\n",
                (uintmax_t)ip->i_number, (uint32_t)uio->uio_offset,
                uio->uio_resid));

        if (uio->uio_offset < 0 || uio->uio_offset > INT_MAX)
                return (EINVAL);
        error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_FAILRECLAIM);
        if (error)
                return (error);

        /*
         * uio->uio_offset carries the number of the entry
         * where we should start returning dirents.
         *
         * We fake up "." if we're not reading the FS root
         * and we always fake up "..".
         *
         * off contains the entry we are starting at,
         * num increments while we are reading.
         */

        off = num = uio->uio_offset;
        faked = (ip->i_number == NTFS_ROOTINO) ? 1 : 2;

        /* Simulate . in every dir except ROOT */
        if (ip->i_number != NTFS_ROOTINO && num == 0) {
                if (vop_write_dirent(&error, uio, ip->i_number,
                    DT_DIR, 1, "."))
                        goto done;
                if (error)
                        goto done;

                num++;
                ncookies++;
        }

        /* Simulate .. in every dir including ROOT */
        if (num == faked - 1) {
                /* XXX NTFS_ROOTINO seems to be wrong here */
                if (vop_write_dirent(&error, uio, NTFS_ROOTINO,
                    DT_DIR, 2, ".."))
                        goto readdone;
                if (error)
                        goto done;

                num++;
                ncookies++;
        }

        for (;;) {
                struct attr_indexentry *iep;

                /*
                 * num is the number of the entry we will return,
                 * but ntfs_ntreaddir takes the entry number of the
                 * ntfs directory listing, so subtract the faked
                 * . and .. entries.
                 */
                error = ntfs_ntreaddir(ntmp, fp, num - faked, &iep);

                if (error)
                        goto done;

                if( NULL == iep )
                        break;

                for (; !(iep->ie_flag & NTFS_IEFLAG_LAST);
                        iep = NTFS_NEXTREC(iep, struct attr_indexentry *))
                {
                        if(!ntfs_isnamepermitted(ntmp,iep))
                                continue;
                        for(i=0, j=0; i < iep->ie_fnamelen; i++, j++) {
                                c = NTFS_U28(iep->ie_fname[i]);
                                if (c&0xFF00)
                                        convname[j++] = (char)(c>>8);
                                convname[j] = (char)c&0xFF;
                        }
                        convname[j] = '\0';
                        if (vop_write_dirent(&error, uio, iep->ie_number,
                            (iep->ie_fflag & NTFS_FFLAG_DIR) ? DT_DIR : DT_REG,
                            j, convname))
                                goto readdone;

                        dprintf(("ntfs_readdir: elem: %d, fname:[%s] type: %d, "
                                 "flag: %d, %s\n",
                                 ncookies, convname, iep->ie_fnametype,
                                 iep->ie_flag,
                                 (iep->ie_fflag & NTFS_FFLAG_DIR) ?
                                        "dir" : "reg"));

                        if (error)
                                goto done;

                        ncookies++;
                        num++;
                }
        }

readdone:
        uio->uio_offset = num;

        dprintf(("ntfs_readdir: %d entries (%d bytes) read\n",
                ncookies,(u_int)(uio->uio_offset - off)));
        dprintf(("ntfs_readdir: off: %u resid: %zd\n",
                (uint32_t)uio->uio_offset, uio->uio_resid));

        if (!error && ap->a_ncookies != NULL) {
                off_t *cookies;
                off_t *cookiep;

                ddprintf(("ntfs_readdir: %d cookies\n",ncookies));
                if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1)
                        panic("ntfs_readdir: unexpected uio from NFS server");
                cookies = kmalloc(ncookies * sizeof(off_t), M_TEMP, M_WAITOK);
                cookiep = cookies;
                while (off < num)
                        *cookiep++ = ++off;

                *ap->a_ncookies = ncookies;
                *ap->a_cookies = cookies;
        }
/*
        if (ap->a_eofflag)
            *ap->a_eofflag = VTONT(vp)->i_size <= uio->uio_offset;
*/
done:
        vn_unlock(vp);
        return (error);
}

/*
 * ntfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp,
 *              struct componentname *a_cnp)
 */
int
ntfs_lookup(struct vop_old_lookup_args *ap)
{
        struct vnode *dvp = ap->a_dvp;
        struct ntnode *dip = VTONT(dvp);
        struct ntfsmount *ntmp = dip->i_mp;
        struct componentname *cnp = ap->a_cnp;
        int error;
        int lockparent = cnp->cn_flags & CNP_LOCKPARENT;
#if NTFS_DEBUG
        int wantparent = cnp->cn_flags & (CNP_LOCKPARENT | CNP_WANTPARENT);
#endif
        dprintf(("ntfs_lookup: \"%.*s\" (%ld bytes) in %ju, lp: %d, wp: %d \n",
                (int)cnp->cn_namelen, cnp->cn_nameptr, cnp->cn_namelen,
                (uintmax_t)dip->i_number, lockparent, wantparent));

        *ap->a_vpp = NULL;

        if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
                dprintf(("ntfs_lookup: faking . directory in %u\n",
                        (uint32_t)dip->i_number));

                vref(dvp);
                *ap->a_vpp = dvp;
                error = 0;
        } else if (cnp->cn_flags & CNP_ISDOTDOT) {
                struct ntvattr *vap;

                dprintf(("ntfs_lookup: faking .. directory in %d\n",
                        (uint32_t)dip->i_number));

                error = ntfs_ntvattrget(ntmp, dip, NTFS_A_NAME, NULL, 0, &vap);
                if(error)
                        return (error);

                VOP__UNLOCK(dvp, 0);
                cnp->cn_flags |= CNP_PDIRUNLOCK;

                dprintf(("ntfs_lookup: parentdir: %d\n",
                         vap->va_a_name->n_pnumber));
                error = VFS_VGET(ntmp->ntm_mountp, NULL,
                                 vap->va_a_name->n_pnumber,ap->a_vpp); 
                ntfs_ntvattrrele(vap);
                if (error) {
                        if (VOP_LOCK(dvp, LK_EXCLUSIVE | LK_RETRY) == 0)
                                cnp->cn_flags &= ~CNP_PDIRUNLOCK;
                        return (error);
                }

                if (lockparent) {
                        error = VOP_LOCK(dvp, LK_EXCLUSIVE);
                        if (error) {
                                vput(*ap->a_vpp);
                                *ap->a_vpp = NULL;
                                return (error);
                        }
                        cnp->cn_flags &= ~CNP_PDIRUNLOCK;
                }
        } else {
                error = ntfs_ntlookupfile(ntmp, dvp, cnp, ap->a_vpp);
                if (error) {
                        dprintf(("ntfs_ntlookupfile: returned %d\n", error));
                        return (error);
                }

                dprintf(("ntfs_lookup: found ino: %u\n",
                        (uint32_t)VTONT(*ap->a_vpp)->i_number));

                if (!lockparent) {
                        VOP__UNLOCK(dvp, 0);
                        cnp->cn_flags |= CNP_PDIRUNLOCK;
                }
        }
        return (error);
}

/*
 * Flush the blocks of a file to disk.
 *
 * This function is worthless for vnodes that represent directories. Maybe we
 * could just do a sync if they try an fsync on a directory file.
 *
 * ntfs_fsync(struct vnode *a_vp, int a_waitfor)
 */
static int
ntfs_fsync(struct vop_fsync_args *ap)
{
        return (0);
}

/*
 * Return POSIX pathconf information applicable to NTFS filesystem
 */
int
ntfs_pathconf(struct vop_pathconf_args *ap)
{
        switch (ap->a_name) {
        case _PC_LINK_MAX:
                *ap->a_retval = 1;
                return (0);
        case _PC_NAME_MAX:
                *ap->a_retval = NTFS_MAXFILENAME;
                return (0);
        case _PC_PATH_MAX:
                *ap->a_retval = PATH_MAX;
                return (0);
        case _PC_CHOWN_RESTRICTED:
                *ap->a_retval = 1;
                return (0);
        case _PC_NO_TRUNC:
                *ap->a_retval = 0;
                return (0);
        default:
                return (EINVAL);
        }
        /* NOTREACHED */
}

/*
 * Global vfs data structures
 */
struct vop_ops ntfs_vnode_vops = {
        .vop_default =          vop_defaultop,
        .vop_getattr =          ntfs_getattr,
        .vop_inactive =         ntfs_inactive,
        .vop_reclaim =          ntfs_reclaim,
        .vop_print =            ntfs_print,
        .vop_pathconf =         ntfs_pathconf,
        .vop_old_lookup =       ntfs_lookup,
        .vop_access =           ntfs_access,
        .vop_close =            ntfs_close,
        .vop_open =             ntfs_open,
        .vop_readdir =          ntfs_readdir,
        .vop_fsync =            ntfs_fsync,
        .vop_bmap =             ntfs_bmap,
        .vop_getpages =         vop_stdgetpages,
        .vop_putpages =         vop_stdputpages,
        .vop_strategy =         ntfs_strategy,
        .vop_read =             ntfs_read,
        .vop_write =            ntfs_write
};