xref: /freebsd/sys/fs/cd9660/cd9660_vnops.c (revision 9d3220061d64b220c0e250dca370b8a5e44dc307)

/*-
 * Copyright (c) 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley
 * by Pace Willisson (pace@blitz.com).  The Rock Ridge Extension
 * Support code is derived from software contributed to Berkeley
 * by Atsushi Murai (amurai@spec.co.jp).
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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.
 *
 *	@(#)cd9660_vnops.c	8.19 (Berkeley) 5/27/95
 * $Id: cd9660_vnops.c,v 1.35 1997/04/15 08:05:08 bde Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/kernel.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/buf.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <miscfs/specfs/specdev.h>
#include <miscfs/fifofs/fifo.h>
#include <sys/malloc.h>
#include <sys/dirent.h>
#include <sys/unistd.h>

#include <isofs/cd9660/iso.h>
#include <isofs/cd9660/cd9660_node.h>
#include <isofs/cd9660/iso_rrip.h>

static int cd9660_setattr __P((struct vop_setattr_args *));
static int cd9660_open __P((struct vop_open_args *));
static int cd9660_close __P((struct vop_close_args *));
static int cd9660_access __P((struct vop_access_args *));
static int cd9660_getattr __P((struct vop_getattr_args *));
static int cd9660_read __P((struct vop_read_args *));
static int cd9660_ioctl __P((struct vop_ioctl_args *));
static int cd9660_select __P((struct vop_select_args *));
static int cd9660_mmap __P((struct vop_mmap_args *));
static int cd9660_seek __P((struct vop_seek_args *));
struct isoreaddir;
static int iso_uiodir __P((struct isoreaddir *idp, struct dirent *dp,
			   off_t off));
static int iso_shipdir __P((struct isoreaddir *idp));
static int cd9660_readdir __P((struct vop_readdir_args *));
static int cd9660_readlink __P((struct vop_readlink_args *ap));
static int cd9660_abortop __P((struct vop_abortop_args *));
static int cd9660_lock __P((struct vop_lock_args *));
static int cd9660_unlock __P((struct vop_unlock_args *));
static int cd9660_strategy __P((struct vop_strategy_args *));
static int cd9660_print __P((struct vop_print_args *));
static int cd9660_islocked __P((struct vop_islocked_args *));

/*
 * Sysctl values for the cd9660 filesystem.
 */
#define	CD9660_CLUSTERREAD	1	/* cluster reading enabled */
#define	CD9660_MAXID		2	/* number of valid cd9660 ids */

#define	CD9660_NAMES { \
	{0, 0}, \
	{ "doclusterread", CTLTYPE_INT}, \
}

/*
 * Setattr call. Only allowed for block and character special devices.
 */
int
cd9660_setattr(ap)
	struct vop_setattr_args /* {
		struct vnodeop_desc *a_desc;
		struct vnode *a_vp;
		struct vattr *a_vap;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	struct vnode *vp = ap->a_vp;
	struct vattr *vap = ap->a_vap;

  	if (vap->va_flags != (u_long)VNOVAL || vap->va_uid != (uid_t)VNOVAL ||
	    vap->va_gid != (gid_t)VNOVAL || vap->va_atime.tv_sec != VNOVAL ||
	    vap->va_mtime.tv_sec != VNOVAL || vap->va_mode != (mode_t)VNOVAL)
		return (EROFS);
	if (vap->va_size != (u_quad_t)VNOVAL) {
 		switch (vp->v_type) {
 		case VDIR:
 			return (EISDIR);
		case VLNK:
		case VREG:
			return (EROFS);
 		case VCHR:
 		case VBLK:
 		case VSOCK:
 		case VFIFO:
			return (0);
		}
	}
	return (0);
}

/*
 * Open called.
 *
 * Nothing to do.
 */
/* ARGSUSED */
static int
cd9660_open(ap)
	struct vop_open_args /* {
		struct vnode *a_vp;
		int  a_mode;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	return (0);
}

/*
 * Close called
 *
 * Update the times on the inode on writeable file systems.
 */
/* ARGSUSED */
static int
cd9660_close(ap)
	struct vop_close_args /* {
		struct vnode *a_vp;
		int  a_fflag;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	return (0);
}

/*
 * Check mode permission on inode pointer. Mode is READ, WRITE or EXEC.
 * The mode is shifted to select the owner/group/other fields. The
 * super user is granted all permissions.
 */
/* ARGSUSED */
static int
cd9660_access(ap)
	struct vop_access_args /* {
		struct vnode *a_vp;
		int  a_mode;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	struct vnode *vp = ap->a_vp;
	struct iso_node *ip = VTOI(vp);
	struct ucred *cred = ap->a_cred;
	mode_t mask, mode = ap->a_mode;
	gid_t *gp;
	int i;

	/*
	 * Disallow write attempts unless the file is a socket,
	 * fifo, or a block or character device resident on the
	 * file system.
	 */
	if (mode & VWRITE) {
		switch (vp->v_type) {
		case VDIR:
		case VLNK:
		case VREG:
			return (EROFS);
		}
	}

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

	mask = 0;

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

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

static int
cd9660_getattr(ap)
	struct vop_getattr_args /* {
		struct vnode *a_vp;
		struct vattr *a_vap;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;

{
	struct vnode *vp = ap->a_vp;
	register struct vattr *vap = ap->a_vap;
	register struct iso_node *ip = VTOI(vp);

	vap->va_fsid	= ip->i_dev;
	vap->va_fileid	= ip->i_number;

	vap->va_mode	= ip->inode.iso_mode;
	vap->va_nlink	= ip->inode.iso_links;
	vap->va_uid	= ip->inode.iso_uid;
	vap->va_gid	= ip->inode.iso_gid;
	vap->va_atime	= ip->inode.iso_atime;
	vap->va_mtime	= ip->inode.iso_mtime;
	vap->va_ctime	= ip->inode.iso_ctime;
	vap->va_rdev	= ip->inode.iso_rdev;

	vap->va_size	= (u_quad_t) ip->i_size;
	if (ip->i_size == 0 && (vap->va_mode & S_IFMT) == S_IFLNK) {
		struct vop_readlink_args rdlnk;
		struct iovec aiov;
		struct uio auio;
		char *cp;

		MALLOC(cp, char *, MAXPATHLEN, M_TEMP, M_WAITOK);
		aiov.iov_base = cp;
		aiov.iov_len = MAXPATHLEN;
		auio.uio_iov = &aiov;
		auio.uio_iovcnt = 1;
		auio.uio_offset = 0;
		auio.uio_rw = UIO_READ;
		auio.uio_segflg = UIO_SYSSPACE;
		auio.uio_procp = ap->a_p;
		auio.uio_resid = MAXPATHLEN;
		rdlnk.a_uio = &auio;
		rdlnk.a_vp = ap->a_vp;
		rdlnk.a_cred = ap->a_cred;
		if (cd9660_readlink(&rdlnk) == 0)
			vap->va_size = MAXPATHLEN - auio.uio_resid;
		FREE(cp, M_TEMP);
	}
	vap->va_flags	= 0;
	vap->va_gen = 1;
	vap->va_blocksize = ip->i_mnt->logical_block_size;
	vap->va_bytes	= (u_quad_t) ip->i_size;
	vap->va_type	= vp->v_type;
	vap->va_filerev	= 0;
	return (0);
}

static int	cd9660_doclusterread = 1;
SYSCTL_NODE(_vfs, MOUNT_CD9660, cd9660, CTLFLAG_RW, 0, "CD9660 filesystem");
SYSCTL_INT(_vfs_cd9660, CD9660_CLUSTERREAD, doclusterread,
		   CTLFLAG_RW, &cd9660_doclusterread, 0, "");

/*
 * Vnode op for reading.
 */
static int
cd9660_read(ap)
	struct vop_read_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		int a_ioflag;
		struct ucred *a_cred;
	} */ *ap;
{
	struct vnode *vp = ap->a_vp;
	register struct uio *uio = ap->a_uio;
	register struct iso_node *ip = VTOI(vp);
	register struct iso_mnt *imp;
	struct buf *bp;
	daddr_t lbn, rablock;
	off_t diff;
	int rasize, error = 0;
	long size, n, on;

	if (uio->uio_resid == 0)
		return (0);
	if (uio->uio_offset < 0)
		return (EINVAL);
	ip->i_flag |= IN_ACCESS;
	imp = ip->i_mnt;
	do {
		lbn = lblkno(imp, uio->uio_offset);
		on = blkoff(imp, uio->uio_offset);
		n = min((u_int)(imp->logical_block_size - on),
			uio->uio_resid);
		diff = (off_t)ip->i_size - uio->uio_offset;
		if (diff <= 0)
			return (0);
		if (diff < n)
			n = diff;
		size = blksize(imp, ip, lbn);
		rablock = lbn + 1;
		if (cd9660_doclusterread) {
			if (lblktosize(imp, rablock) <= ip->i_size)
				error = cluster_read(vp, (off_t)ip->i_size,
				         lbn, size, NOCRED, uio->uio_resid,
					 (ap->a_ioflag >> 16), &bp);
			else
				error = bread(vp, lbn, size, NOCRED, &bp);
		} else {
			if (vp->v_lastr + 1 == lbn &&
			    lblktosize(imp, rablock) < ip->i_size) {
				rasize = blksize(imp, ip, rablock);
				error = breadn(vp, lbn, size, &rablock,
					       &rasize, 1, NOCRED, &bp);
			} else
				error = bread(vp, lbn, size, NOCRED, &bp);
		}
		vp->v_lastr = lbn;
		n = min(n, size - bp->b_resid);
		if (error) {
			brelse(bp);
			return (error);
		}

		error = uiomove(bp->b_data + on, (int)n, uio);
		brelse(bp);
	} while (error == 0 && uio->uio_resid > 0 && n != 0);
	return (error);
}

/* ARGSUSED */
static int
cd9660_ioctl(ap)
	struct vop_ioctl_args /* {
		struct vnode *a_vp;
		u_long a_command;
		caddr_t  a_data;
		int  a_fflag;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	printf("You did ioctl for isofs !!\n");
	return (ENOTTY);
}

/* ARGSUSED */
static int
cd9660_select(ap)
	struct vop_select_args /* {
		struct vnode *a_vp;
		int  a_which;
		int  a_fflags;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{

	/*
	 * We should really check to see if I/O is possible.
	 */
	return (1);
}

/*
 * Mmap a file
 *
 * NB Currently unsupported.
 */
/* ARGSUSED */
static int
cd9660_mmap(ap)
	struct vop_mmap_args /* {
		struct vnode *a_vp;
		int  a_fflags;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{

	return (EINVAL);
}

/*
 * Seek on a file
 *
 * Nothing to do, so just return.
 */
/* ARGSUSED */
static int
cd9660_seek(ap)
	struct vop_seek_args /* {
		struct vnode *a_vp;
		off_t  a_oldoff;
		off_t  a_newoff;
		struct ucred *a_cred;
	} */ *ap;
{

	return (0);
}

/*
 * Structure for reading directories
 */
struct isoreaddir {
	struct dirent saveent;
	struct dirent assocent;
	struct dirent current;
	off_t saveoff;
	off_t assocoff;
	off_t curroff;
	struct uio *uio;
	off_t uio_off;
	int eofflag;
	u_long *cookies;
	int ncookies;
};

int
iso_uiodir(idp,dp,off)
	struct isoreaddir *idp;
	struct dirent *dp;
	off_t off;
{
	int error;

	dp->d_name[dp->d_namlen] = 0;
	dp->d_reclen = GENERIC_DIRSIZ(dp);

	if (idp->uio->uio_resid < dp->d_reclen) {
		idp->eofflag = 0;
		return (-1);
	}

	if (idp->cookies) {
		if (idp->ncookies <= 0) {
			idp->eofflag = 0;
			return (-1);
		}

		*idp->cookies++ = off;
		--idp->ncookies;
	}

	if (error = uiomove((caddr_t) dp,dp->d_reclen,idp->uio))
		return (error);
	idp->uio_off = off;
	return (0);
}

int
iso_shipdir(idp)
	struct isoreaddir *idp;
{
	struct dirent *dp;
	int cl, sl, assoc;
	int error;
	char *cname, *sname;

	cl = idp->current.d_namlen;
	cname = idp->current.d_name;
assoc = (cl > 1) && (*cname == ASSOCCHAR);
	if (assoc) {
		cl--;
		cname++;
	}

	dp = &idp->saveent;
	sname = dp->d_name;
	if (!(sl = dp->d_namlen)) {
		dp = &idp->assocent;
		sname = dp->d_name + 1;
		sl = dp->d_namlen - 1;
	}
	if (sl > 0) {
		if (sl != cl
		    || bcmp(sname,cname,sl)) {
			if (idp->assocent.d_namlen) {
				if (error = iso_uiodir(idp,&idp->assocent,idp->assocoff))
					return (error);
				idp->assocent.d_namlen = 0;
			}
			if (idp->saveent.d_namlen) {
				if (error = iso_uiodir(idp,&idp->saveent,idp->saveoff))
					return (error);
				idp->saveent.d_namlen = 0;
			}
		}
	}
	idp->current.d_reclen = GENERIC_DIRSIZ(&idp->current);
	if (assoc) {
		idp->assocoff = idp->curroff;
		bcopy(&idp->current,&idp->assocent,idp->current.d_reclen);
	} else {
		idp->saveoff = idp->curroff;
		bcopy(&idp->current,&idp->saveent,idp->current.d_reclen);
	}
	return (0);
}

/*
 * Vnode op for readdir
 */
static int
cd9660_readdir(ap)
	struct vop_readdir_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		struct ucred *a_cred;
		int *a_eofflag;
		int *a_ncookies;
		u_long *a_cookies;
	} */ *ap;
{
	register struct uio *uio = ap->a_uio;
	struct isoreaddir *idp;
	struct vnode *vdp = ap->a_vp;
	struct iso_node *dp;
	struct iso_mnt *imp;
	struct buf *bp = NULL;
	struct iso_directory_record *ep;
	int entryoffsetinblock;
	doff_t endsearch;
	u_long bmask;
	int error = 0;
	int reclen;
	u_short namelen;
	int ncookies = 0;
	u_long *cookies = NULL;

	dp = VTOI(vdp);
	imp = dp->i_mnt;
	bmask = imp->im_bmask;

	MALLOC(idp, struct isoreaddir *, sizeof(*idp), M_TEMP, M_WAITOK);
	idp->saveent.d_namlen = idp->assocent.d_namlen = 0;
	/*
	 * XXX
	 * Is it worth trying to figure out the type?
	 */
	idp->saveent.d_type = idp->assocent.d_type = idp->current.d_type =
	    DT_UNKNOWN;
	idp->uio = uio;
	if (ap->a_ncookies == NULL) {
		idp->cookies = NULL;
	} else {
		/*
		 * Guess the number of cookies needed.
		 */
		ncookies = uio->uio_resid / 16;
		MALLOC(cookies, u_long *, ncookies * sizeof(u_int), M_TEMP,
		    M_WAITOK);
		idp->cookies = cookies;
		idp->ncookies = ncookies;
	}
	idp->eofflag = 1;
	idp->curroff = uio->uio_offset;

	if ((entryoffsetinblock = idp->curroff & bmask) &&
	    (error = VOP_BLKATOFF(vdp, (off_t)idp->curroff, NULL, &bp))) {
		FREE(idp, M_TEMP);
		return (error);
	}
	endsearch = dp->i_size;

	while (idp->curroff < endsearch) {
		/*
		 * If offset is on a block boundary,
		 * read the next directory block.
		 * Release previous if it exists.
		 */
		if ((idp->curroff & bmask) == 0) {
			if (bp != NULL)
				brelse(bp);
			if (error =
			    VOP_BLKATOFF(vdp, (off_t)idp->curroff, NULL, &bp))
				break;
			entryoffsetinblock = 0;
		}
		/*
		 * Get pointer to next entry.
		 */
		ep = (struct iso_directory_record *)
			((char *)bp->b_data + entryoffsetinblock);

		reclen = isonum_711(ep->length);
		if (reclen == 0) {
			/* skip to next block, if any */
			idp->curroff =
			    (idp->curroff & ~bmask) + imp->logical_block_size;
			continue;
		}

		if (reclen < ISO_DIRECTORY_RECORD_SIZE) {
			error = EINVAL;
			/* illegal entry, stop */
			break;
		}

		if (entryoffsetinblock + reclen > imp->logical_block_size) {
			error = EINVAL;
			/* illegal directory, so stop looking */
			break;
		}

		idp->current.d_namlen = isonum_711(ep->name_len);

		if (reclen < ISO_DIRECTORY_RECORD_SIZE + idp->current.d_namlen) {
			error = EINVAL;
			/* illegal entry, stop */
			break;
		}

		if (isonum_711(ep->flags)&2)
			idp->current.d_fileno = isodirino(ep, imp);
		else
			idp->current.d_fileno = dbtob(bp->b_blkno) +
				entryoffsetinblock;

		idp->curroff += reclen;

		switch (imp->iso_ftype) {
		case ISO_FTYPE_RRIP:
			cd9660_rrip_getname(ep,idp->current.d_name, &namelen,
					   &idp->current.d_fileno,imp);
			idp->current.d_namlen = (u_char)namelen;
			if (idp->current.d_namlen)
				error = iso_uiodir(idp,&idp->current,idp->curroff);
			break;
		default: /* ISO_FTYPE_DEFAULT || ISO_FTYPE_9660 || ISO_FTYPE_HIGH_SIERRA*/
			strcpy(idp->current.d_name,"..");
			switch (ep->name[0]) {
			case 0:
				idp->current.d_namlen = 1;
				error = iso_uiodir(idp,&idp->current,idp->curroff);
				break;
			case 1:
				idp->current.d_namlen = 2;
				error = iso_uiodir(idp,&idp->current,idp->curroff);
				break;
			default:
				isofntrans(ep->name,idp->current.d_namlen,
					   idp->current.d_name, &namelen,
					   imp->iso_ftype == ISO_FTYPE_9660,
					   isonum_711(ep->flags)&4);
				idp->current.d_namlen = (u_char)namelen;
				if (imp->iso_ftype == ISO_FTYPE_DEFAULT)
					error = iso_shipdir(idp);
				else
					error = iso_uiodir(idp,&idp->current,idp->curroff);
				break;
			}
		}
		if (error)
			break;

		entryoffsetinblock += reclen;
	}

	if (!error && imp->iso_ftype == ISO_FTYPE_DEFAULT) {
		idp->current.d_namlen = 0;
		error = iso_shipdir(idp);
	}
	if (error < 0)
		error = 0;

	if (ap->a_ncookies != NULL) {
		if (error)
			free(cookies, M_TEMP);
		else {
			/*
			 * Work out the number of cookies actually used.
			 */
			*ap->a_ncookies = ncookies - idp->ncookies;
			*ap->a_cookies = cookies;
		}
	}

	if (bp)
		brelse (bp);

	uio->uio_offset = idp->uio_off;
	*ap->a_eofflag = idp->eofflag;

	FREE(idp, M_TEMP);

	return (error);
}

/*
 * Return target name of a symbolic link
 * Shouldn't we get the parent vnode and read the data from there?
 * This could eventually result in deadlocks in cd9660_lookup.
 * But otherwise the block read here is in the block buffer two times.
 */
typedef struct iso_directory_record ISODIR;
typedef struct iso_node		    ISONODE;
typedef struct iso_mnt		    ISOMNT;
static int
cd9660_readlink(ap)
	struct vop_readlink_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		struct ucred *a_cred;
	} */ *ap;
{
	ISONODE	*ip;
	ISODIR	*dirp;
	ISOMNT	*imp;
	struct	buf *bp;
	struct	uio *uio;
	u_short	symlen;
	int	error;
	char	*symname;

	ip  = VTOI(ap->a_vp);
	imp = ip->i_mnt;
	uio = ap->a_uio;

	if (imp->iso_ftype != ISO_FTYPE_RRIP)
		return (EINVAL);

	/*
	 * Get parents directory record block that this inode included.
	 */
	error = bread(imp->im_devvp,
		      (ip->i_number >> imp->im_bshift) <<
		      (imp->im_bshift - DEV_BSHIFT),
		      imp->logical_block_size, NOCRED, &bp);
	if (error) {
		brelse(bp);
		return (EINVAL);
	}

	/*
	 * Setup the directory pointer for this inode
	 */
	dirp = (ISODIR *)(bp->b_data + (ip->i_number & imp->im_bmask));

	/*
	 * Just make sure, we have a right one....
	 *   1: Check not cross boundary on block
	 */
	if ((ip->i_number & imp->im_bmask) + isonum_711(dirp->length)
	    > (unsigned)imp->logical_block_size) {
		brelse(bp);
		return (EINVAL);
	}

	/*
	 * Now get a buffer
	 * Abuse a namei buffer for now.
	 */
	if (uio->uio_segflg == UIO_SYSSPACE)
		symname = uio->uio_iov->iov_base;
	else
		MALLOC(symname, char *, MAXPATHLEN, M_NAMEI, M_WAITOK);

	/*
	 * Ok, we just gathering a symbolic name in SL record.
	 */
	if (cd9660_rrip_getsymname(dirp, symname, &symlen, imp) == 0) {
		if (uio->uio_segflg != UIO_SYSSPACE)
			FREE(symname, M_NAMEI);
		brelse(bp);
		return (EINVAL);
	}
	/*
	 * Don't forget before you leave from home ;-)
	 */
	brelse(bp);

	/*
	 * return with the symbolic name to caller's.
	 */
	if (uio->uio_segflg != UIO_SYSSPACE) {
		error = uiomove(symname, symlen, uio);
		FREE(symname, M_NAMEI);
		return (error);
	}
	uio->uio_resid -= symlen;
	uio->uio_iov->iov_base += symlen;
	uio->uio_iov->iov_len -= symlen;
	return (0);
}

/*
 * Ufs abort op, called after namei() when a CREATE/DELETE isn't actually
 * done. If a buffer has been saved in anticipation of a CREATE, delete it.
 */
static int
cd9660_abortop(ap)
	struct vop_abortop_args /* {
		struct vnode *a_dvp;
		struct componentname *a_cnp;
	} */ *ap;
{
	if ((ap->a_cnp->cn_flags & (HASBUF | SAVESTART)) == HASBUF)
		FREE(ap->a_cnp->cn_pnbuf, M_NAMEI);
	return (0);
}

/*
 * Lock an inode.
 */
static int
cd9660_lock(ap)
	struct vop_lock_args /* {
		struct vnode *a_vp;
		int a_flags;
		struct proc *a_p;
	} */ *ap;
{
	struct vnode *vp = ap->a_vp;

	return (lockmgr(&VTOI(vp)->i_lock, ap->a_flags, &vp->v_interlock,
		ap->a_p));
}

/*
 * Unlock an inode.
 */
static int
cd9660_unlock(ap)
	struct vop_unlock_args /* {
		struct vnode *a_vp;
		int a_flags;
		struct proc *a_p;
	} */ *ap;
{
	struct vnode *vp = ap->a_vp;

	return (lockmgr(&VTOI(vp)->i_lock, ap->a_flags | LK_RELEASE,
		&vp->v_interlock, ap->a_p));
}

/*
 * Calculate the logical to physical mapping if not done already,
 * then call the device strategy routine.
 */
static int
cd9660_strategy(ap)
	struct vop_strategy_args /* {
		struct buf *a_bp;
	} */ *ap;
{
	register struct buf *bp = ap->a_bp;
	register struct vnode *vp = bp->b_vp;
	register struct iso_node *ip;
	int error;

	ip = VTOI(vp);
	if (vp->v_type == VBLK || vp->v_type == VCHR)
		panic("cd9660_strategy: spec");
	if (bp->b_blkno == bp->b_lblkno) {
		if ((error =
		    VOP_BMAP(vp, bp->b_lblkno, NULL, &bp->b_blkno, NULL, NULL))) {
			bp->b_error = error;
			bp->b_flags |= B_ERROR;
			biodone(bp);
			return (error);
		}
		if ((long)bp->b_blkno == -1)
			clrbuf(bp);
	}
	if ((long)bp->b_blkno == -1) {
		biodone(bp);
		return (0);
	}
	vp = ip->i_devvp;
	bp->b_dev = vp->v_rdev;
	VOCALL (vp->v_op, VOFFSET(vop_strategy), ap);
	return (0);
}

/*
 * Print out the contents of an inode.
 */
static int
cd9660_print(ap)
	struct vop_print_args /* {
		struct vnode *a_vp;
	} */ *ap;
{

	printf("tag VT_ISOFS, isofs vnode\n");
	return (0);
}

/*
 * Check for a locked inode.
 */
int
cd9660_islocked(ap)
	struct vop_islocked_args /* {
		struct vnode *a_vp;
	} */ *ap;
{

	return (lockstatus(&VTOI(ap->a_vp)->i_lock));
}

/*
 * Return POSIX pathconf information applicable to cd9660 filesystems.
 */
int
cd9660_pathconf(ap)
	struct vop_pathconf_args /* {
		struct vnode *a_vp;
		int a_name;
		register_t *a_retval;
	} */ *ap;
{

	switch (ap->a_name) {
	case _PC_LINK_MAX:
		*ap->a_retval = 1;
		return (0);
	case _PC_NAME_MAX:
		if (VTOI(ap->a_vp)->i_mnt->iso_ftype == ISO_FTYPE_RRIP)
			*ap->a_retval = NAME_MAX;
		else
			*ap->a_retval = 37;
		return (0);
	case _PC_PATH_MAX:
		*ap->a_retval = PATH_MAX;
		return (0);
	case _PC_PIPE_BUF:
		*ap->a_retval = PIPE_BUF;
		return (0);
	case _PC_CHOWN_RESTRICTED:
		*ap->a_retval = 1;
		return (0);
	case _PC_NO_TRUNC:
		*ap->a_retval = 1;
		return (0);
	default:
		return (EINVAL);
	}
	/* NOTREACHED */
}

/*
 * Global vfs data structures for isofs
 */
#define cd9660_create \
	((int (*) __P((struct  vop_create_args *)))eopnotsupp)
#define cd9660_mknod ((int (*) __P((struct  vop_mknod_args *)))eopnotsupp)
#define cd9660_write ((int (*) __P((struct  vop_write_args *)))eopnotsupp)
#ifdef NFS
#define	 cd9660_lease_check lease_check
#else
#define	 cd9660_lease_check ((int (*) __P((struct vop_lease_args *)))nullop)
#endif
#define cd9660_fsync ((int (*) __P((struct  vop_fsync_args *)))nullop)
#define cd9660_remove \
	((int (*) __P((struct  vop_remove_args *)))eopnotsupp)
#define cd9660_link ((int (*) __P((struct  vop_link_args *)))eopnotsupp)
#define cd9660_rename \
	((int (*) __P((struct  vop_rename_args *)))eopnotsupp)
#define cd9660_mkdir ((int (*) __P((struct  vop_mkdir_args *)))eopnotsupp)
#define cd9660_rmdir ((int (*) __P((struct  vop_rmdir_args *)))eopnotsupp)
#define cd9660_symlink \
	((int (*) __P((struct vop_symlink_args *)))eopnotsupp)
#define cd9660_advlock \
	((int (*) __P((struct vop_advlock_args *)))eopnotsupp)
#define cd9660_valloc ((int(*) __P(( \
		struct vnode *pvp, \
		int mode, \
		struct ucred *cred, \
		struct vnode **vpp))) eopnotsupp)
#define cd9660_vfree ((int (*) __P((struct  vop_vfree_args *)))eopnotsupp)
#define cd9660_truncate \
	((int (*) __P((struct  vop_truncate_args *)))eopnotsupp)
#define cd9660_update \
	((int (*) __P((struct  vop_update_args *)))eopnotsupp)
#define cd9660_bwrite \
	((int (*) __P((struct  vop_bwrite_args *)))eopnotsupp)

/*
 * Global vfs data structures for cd9660
 */
vop_t **cd9660_vnodeop_p;
struct vnodeopv_entry_desc cd9660_vnodeop_entries[] = {

	{ &vop_default_desc, (vop_t *)vn_default_error },
	{ &vop_lookup_desc, (vop_t *)cd9660_lookup },	/* lookup */
	{ &vop_create_desc, (vop_t *)cd9660_create },	/* create */
	{ &vop_mknod_desc, (vop_t *)cd9660_mknod },	/* mknod */
	{ &vop_open_desc, (vop_t *)cd9660_open },	/* open */
	{ &vop_close_desc, (vop_t *)cd9660_close },	/* close */
	{ &vop_access_desc, (vop_t *)cd9660_access },	/* access */
	{ &vop_getattr_desc, (vop_t *)cd9660_getattr },	/* getattr */
	{ &vop_setattr_desc, (vop_t *)cd9660_setattr },	/* setattr */
	{ &vop_read_desc, (vop_t *)cd9660_read },	/* read */
	{ &vop_write_desc, (vop_t *)cd9660_write },	/* write */
	{ &vop_lease_desc, (vop_t *)cd9660_lease_check },/* lease */
	{ &vop_ioctl_desc, (vop_t *)cd9660_ioctl },	/* ioctl */
	{ &vop_select_desc, (vop_t *)cd9660_select },	/* select */
	{ &vop_revoke_desc, (vop_t *)cd9660_revoke },	/* revoke */
	{ &vop_mmap_desc, (vop_t *)cd9660_mmap },	/* mmap */
	{ &vop_fsync_desc, (vop_t *)cd9660_fsync },	/* fsync */
	{ &vop_seek_desc, (vop_t *)cd9660_seek },	/* seek */
	{ &vop_remove_desc, (vop_t *)cd9660_remove },	/* remove */
	{ &vop_link_desc, (vop_t *)cd9660_link },	/* link */
	{ &vop_rename_desc, (vop_t *)cd9660_rename },	/* rename */
	{ &vop_mkdir_desc, (vop_t *)cd9660_mkdir },	/* mkdir */
	{ &vop_rmdir_desc, (vop_t *)cd9660_rmdir },	/* rmdir */
	{ &vop_symlink_desc, (vop_t *)cd9660_symlink },	/* symlink */
	{ &vop_readdir_desc, (vop_t *)cd9660_readdir },	/* readdir */
	{ &vop_readlink_desc, (vop_t *)cd9660_readlink },/* readlink */
	{ &vop_abortop_desc, (vop_t *)cd9660_abortop },	/* abortop */
	{ &vop_inactive_desc, (vop_t *)cd9660_inactive },/* inactive */
	{ &vop_reclaim_desc, (vop_t *)cd9660_reclaim },	/* reclaim */
	{ &vop_lock_desc, (vop_t *)cd9660_lock },	/* lock */
	{ &vop_unlock_desc, (vop_t *)cd9660_unlock },	/* unlock */
	{ &vop_bmap_desc, (vop_t *)cd9660_bmap },	/* bmap */
	{ &vop_strategy_desc, (vop_t *)cd9660_strategy },/* strategy */
	{ &vop_print_desc, (vop_t *)cd9660_print },	/* print */
	{ &vop_islocked_desc, (vop_t *)cd9660_islocked },/* islocked */
	{ &vop_pathconf_desc, (vop_t *)cd9660_pathconf },/* pathconf */
	{ &vop_advlock_desc, (vop_t *)cd9660_advlock },	/* advlock */
	{ &vop_blkatoff_desc, (vop_t *)cd9660_blkatoff },/* blkatoff */
	{ &vop_valloc_desc, (vop_t *)cd9660_valloc },	/* valloc */
	{ &vop_vfree_desc, (vop_t *)cd9660_vfree },	/* vfree */
	{ &vop_truncate_desc, (vop_t *)cd9660_truncate },/* truncate */
	{ &vop_update_desc, (vop_t *)cd9660_update },	/* update */
	{ &vop_bwrite_desc, (vop_t *)vn_bwrite },
	{ NULL, NULL }
};
static struct vnodeopv_desc cd9660_vnodeop_opv_desc =
	{ &cd9660_vnodeop_p, cd9660_vnodeop_entries };
VNODEOP_SET(cd9660_vnodeop_opv_desc);

/*
 * Special device vnode ops
 */
vop_t **cd9660_specop_p;
struct vnodeopv_entry_desc cd9660_specop_entries[] = {
	{ &vop_default_desc, (vop_t *)vn_default_error },
	{ &vop_lookup_desc, (vop_t *)spec_lookup },	/* lookup */
	{ &vop_create_desc, (vop_t *)spec_create },	/* create */
	{ &vop_mknod_desc, (vop_t *)spec_mknod },	/* mknod */
	{ &vop_open_desc, (vop_t *)spec_open },		/* open */
	{ &vop_close_desc, (vop_t *)spec_close },	/* close */
	{ &vop_access_desc, (vop_t *)cd9660_access },	/* access */
	{ &vop_getattr_desc, (vop_t *)cd9660_getattr },	/* getattr */
	{ &vop_setattr_desc, (vop_t *)cd9660_setattr },	/* setattr */
	{ &vop_read_desc, (vop_t *)spec_read },		/* read */
	{ &vop_write_desc, (vop_t *)spec_write },	/* write */
	{ &vop_lease_desc, (vop_t *)spec_lease_check },	/* lease */
	{ &vop_ioctl_desc, (vop_t *)spec_ioctl },	/* ioctl */
	{ &vop_select_desc, (vop_t *)spec_select },	/* select */
	{ &vop_revoke_desc, (vop_t *)spec_revoke },	/* revoke */
	{ &vop_mmap_desc, (vop_t *)spec_mmap },		/* mmap */
	{ &vop_fsync_desc, (vop_t *)spec_fsync },	/* fsync */
	{ &vop_seek_desc, (vop_t *)spec_seek },		/* seek */
	{ &vop_remove_desc, (vop_t *)spec_remove },	/* remove */
	{ &vop_link_desc, (vop_t *)spec_link },		/* link */
	{ &vop_rename_desc, (vop_t *)spec_rename },	/* rename */
	{ &vop_mkdir_desc, (vop_t *)spec_mkdir },	/* mkdir */
	{ &vop_rmdir_desc, (vop_t *)spec_rmdir },	/* rmdir */
	{ &vop_symlink_desc, (vop_t *)spec_symlink },	/* symlink */
	{ &vop_readdir_desc, (vop_t *)spec_readdir },	/* readdir */
	{ &vop_readlink_desc, (vop_t *)spec_readlink },	/* readlink */
	{ &vop_abortop_desc, (vop_t *)spec_abortop },	/* abortop */
	{ &vop_inactive_desc, (vop_t *)cd9660_inactive },/* inactive */
	{ &vop_reclaim_desc, (vop_t *)cd9660_reclaim },	/* reclaim */
	{ &vop_lock_desc, (vop_t *)cd9660_lock },	/* lock */
	{ &vop_unlock_desc, (vop_t *)cd9660_unlock },	/* unlock */
	{ &vop_bmap_desc, (vop_t *)spec_bmap },		/* bmap */
	{ &vop_strategy_desc, (vop_t *)spec_strategy },	/* strategy */
	{ &vop_print_desc, (vop_t *)cd9660_print },	/* print */
	{ &vop_islocked_desc, (vop_t *)cd9660_islocked },/* islocked */
	{ &vop_pathconf_desc, (vop_t *)spec_pathconf },	/* pathconf */
	{ &vop_advlock_desc, (vop_t *)spec_advlock },	/* advlock */
	{ &vop_blkatoff_desc, (vop_t *)spec_blkatoff },	/* blkatoff */
	{ &vop_valloc_desc, (vop_t *)spec_valloc },	/* valloc */
	{ &vop_vfree_desc, (vop_t *)spec_vfree },	/* vfree */
	{ &vop_truncate_desc, (vop_t *)spec_truncate },	/* truncate */
	{ &vop_update_desc, (vop_t *)cd9660_update },	/* update */
	{ &vop_bwrite_desc, (vop_t *)vn_bwrite },
	{ NULL, NULL }
};
static struct vnodeopv_desc cd9660_specop_opv_desc =
	{ &cd9660_specop_p, cd9660_specop_entries };
VNODEOP_SET(cd9660_specop_opv_desc);

vop_t **cd9660_fifoop_p;
struct vnodeopv_entry_desc cd9660_fifoop_entries[] = {
	{ &vop_default_desc, (vop_t *)vn_default_error },
	{ &vop_lookup_desc, (vop_t *)fifo_lookup },	/* lookup */
	{ &vop_create_desc, (vop_t *)fifo_create },	/* create */
	{ &vop_mknod_desc, (vop_t *)fifo_mknod },	/* mknod */
	{ &vop_open_desc, (vop_t *)fifo_open },		/* open */
	{ &vop_close_desc, (vop_t *)fifo_close },	/* close */
	{ &vop_access_desc, (vop_t *)cd9660_access },	/* access */
	{ &vop_getattr_desc, (vop_t *)cd9660_getattr },	/* getattr */
	{ &vop_setattr_desc, (vop_t *)cd9660_setattr },	/* setattr */
	{ &vop_read_desc, (vop_t *)fifo_read },		/* read */
	{ &vop_write_desc, (vop_t *)fifo_write },	/* write */
	{ &vop_lease_desc, (vop_t *)fifo_lease_check },	/* lease */
	{ &vop_ioctl_desc, (vop_t *)fifo_ioctl },	/* ioctl */
	{ &vop_select_desc, (vop_t *)fifo_select },	/* select */
	{ &vop_revoke_desc, (vop_t *)fifo_revoke },	/* revoke */
	{ &vop_mmap_desc, (vop_t *)fifo_mmap },		/* mmap */
	{ &vop_fsync_desc, (vop_t *)fifo_fsync },	/* fsync */
	{ &vop_seek_desc, (vop_t *)fifo_seek },		/* seek */
	{ &vop_remove_desc, (vop_t *)fifo_remove },	/* remove */
	{ &vop_link_desc, (vop_t *)fifo_link }	,	/* link */
	{ &vop_rename_desc, (vop_t *)fifo_rename },	/* rename */
	{ &vop_mkdir_desc, (vop_t *)fifo_mkdir },	/* mkdir */
	{ &vop_rmdir_desc, (vop_t *)fifo_rmdir },	/* rmdir */
	{ &vop_symlink_desc, (vop_t *)fifo_symlink },	/* symlink */
	{ &vop_readdir_desc, (vop_t *)fifo_readdir },	/* readdir */
	{ &vop_readlink_desc, (vop_t *)fifo_readlink },	/* readlink */
	{ &vop_abortop_desc, (vop_t *)fifo_abortop },	/* abortop */
	{ &vop_inactive_desc, (vop_t *)cd9660_inactive },/* inactive */
	{ &vop_reclaim_desc, (vop_t *)cd9660_reclaim },	/* reclaim */
	{ &vop_lock_desc, (vop_t *)cd9660_lock },	/* lock */
	{ &vop_unlock_desc, (vop_t *)cd9660_unlock },	/* unlock */
	{ &vop_bmap_desc, (vop_t *)fifo_bmap },		/* bmap */
	{ &vop_strategy_desc, (vop_t *)fifo_strategy },	/* strategy */
	{ &vop_print_desc, (vop_t *)cd9660_print },	/* print */
	{ &vop_islocked_desc, (vop_t *)cd9660_islocked },/* islocked */
	{ &vop_pathconf_desc, (vop_t *)fifo_pathconf },	/* pathconf */
	{ &vop_advlock_desc, (vop_t *)fifo_advlock },	/* advlock */
	{ &vop_blkatoff_desc, (vop_t *)fifo_blkatoff },	/* blkatoff */
	{ &vop_valloc_desc, (vop_t *)fifo_valloc },	/* valloc */
	{ &vop_vfree_desc, (vop_t *)fifo_vfree },	/* vfree */
	{ &vop_truncate_desc, (vop_t *)fifo_truncate },	/* truncate */
	{ &vop_update_desc, (vop_t *)cd9660_update },	/* update */
	{ &vop_bwrite_desc, (vop_t *)vn_bwrite },
	{ NULL, NULL }
};
static struct vnodeopv_desc cd9660_fifoop_opv_desc =
	{ &cd9660_fifoop_p, cd9660_fifoop_entries };

VNODEOP_SET(cd9660_fifoop_opv_desc);