/*      $NetBSD: cd9660_vnops.c,v 1.63 2024/02/02 20:27:26 christos Exp $       */

/*-
 * 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. 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      8.15 (Berkeley) 5/27/95
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: cd9660_vnops.c,v 1.63 2024/02/02 20:27:26 christos Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/resourcevar.h>
#include <sys/kernel.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <sys/dirent.h>
#include <sys/kauth.h>

#include <miscfs/fifofs/fifo.h>
#include <miscfs/genfs/genfs.h>
#include <miscfs/specfs/specdev.h>

#include <fs/cd9660/iso.h>
#include <fs/cd9660/cd9660_extern.h>
#include <fs/cd9660/cd9660_node.h>
#include <fs/cd9660/cd9660_mount.h>
#include <fs/cd9660/iso_rrip.h>
#include <fs/cd9660/cd9660_mount.h>

/*
 * 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;
        off_t *cookies;
        int ncookies;
};

int     iso_uiodir(struct isoreaddir *, struct dirent *, off_t);
int     iso_shipdir(struct isoreaddir *);

static int
cd9660_check_possible(struct vnode *vp, struct iso_node *ip, accmode_t accmode)
{

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

        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.
 */
static int
cd9660_check_permitted(struct vnode *vp, struct iso_node *ip, accmode_t accmode,
    kauth_cred_t cred)
{
        accmode_t file_mode;
        uid_t uid;
        gid_t gid;

        file_mode = ip->inode.iso_mode & ALLPERMS;
        file_mode &= (vp->v_type == VDIR) ? ip->i_mnt->im_dmask : ip->i_mnt->im_fmask;

        uid = (ip->i_mnt->im_flags & ISOFSMNT_UID) ?
            ip->i_mnt->im_uid : ip->inode.iso_uid;
        gid = (ip->i_mnt->im_flags & ISOFSMNT_GID) ?
            ip->i_mnt->im_gid : ip->inode.iso_gid;

        return kauth_authorize_vnode(cred, KAUTH_ACCESS_ACTION(accmode,
            vp->v_type, file_mode), vp, NULL,
            genfs_can_access(vp, cred, uid, gid,
            file_mode, NULL, accmode));
}

int
cd9660_access(void *v)
{
        struct vop_access_args /* {
                struct vnode *a_vp;
                accmode_t  a_accmode;
                kauth_cred_t a_cred;
        } */ *ap = v;
        struct vnode *vp = ap->a_vp;
        struct iso_node *ip = VTOI(vp);
        int error;

        error = cd9660_check_possible(vp, ip, ap->a_accmode);
        if (error)
                return error;

        error = cd9660_check_permitted(vp, ip, ap->a_accmode, ap->a_cred);

        return error;
}

int
cd9660_getattr(void *v)
{
        struct vop_getattr_args /* {
                struct vnode *a_vp;
                struct vattr *a_vap;
                kauth_cred_t a_cred;
        } */ *ap = v;
        struct vnode *vp = ap->a_vp;
        struct iso_node *ip = VTOI(vp);
        struct vattr *vap = ap->a_vap;

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

        vap->va_mode    = ip->inode.iso_mode & ALLPERMS;
        vap->va_mode &= (vp->v_type == VDIR) ? ip->i_mnt->im_dmask : ip->i_mnt->im_fmask;
        vap->va_nlink   = ip->inode.iso_links;
        vap->va_uid     = (ip->i_mnt->im_flags & ISOFSMNT_UID) ?
            ip->i_mnt->im_uid : ip->inode.iso_uid;
        vap->va_gid     = (ip->i_mnt->im_flags & ISOFSMNT_GID) ?
            ip->i_mnt->im_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 && vp->v_type == VLNK) {
                struct vop_readlink_args rdlnk;
                struct iovec aiov;
                struct uio auio;
                char *cp;

                cp = (char *)malloc(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_resid = MAXPATHLEN;
                UIO_SETUP_SYSSPACE(&auio);
                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;
        return (0);
}

/*
 * Vnode op for reading.
 */
int
cd9660_read(void *v)
{
        struct vop_read_args /* {
                struct vnode *a_vp;
                struct uio *a_uio;
                int a_ioflag;
                kauth_cred_t a_cred;
        } */ *ap = v;
        struct vnode *vp = ap->a_vp;
        struct uio *uio = ap->a_uio;
        struct iso_node *ip = VTOI(vp);
        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);
        if (uio->uio_offset >= ip->i_size)
                return 0;
        ip->i_flag |= IN_ACCESS;
        imp = ip->i_mnt;

        if (vp->v_type == VREG) {
                const int advice = IO_ADV_DECODE(ap->a_ioflag);
                error = 0;

                while (uio->uio_resid > 0) {
                        vsize_t bytelen = MIN(ip->i_size - uio->uio_offset,
                                              uio->uio_resid);

                        if (bytelen == 0)
                                break;
                        error = ubc_uiomove(&vp->v_uobj, uio, bytelen, advice,
                            UBC_READ | UBC_PARTIALOK | UBC_VNODE_FLAGS(vp));
                        if (error)
                                break;
                }
                goto out;
        }

        do {
                lbn = cd9660_lblkno(imp, uio->uio_offset);
                on = cd9660_blkoff(imp, uio->uio_offset);
                n = MIN(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 = cd9660_blksize(imp, ip, lbn);
                rablock = lbn + 1;
                if (cd9660_lblktosize(imp, rablock) < ip->i_size) {
                        rasize = cd9660_blksize(imp, ip, rablock);
                        error = breadn(vp, lbn, size, &rablock,
                                       &rasize, 1, 0, &bp);
                } else {
                        error = bread(vp, lbn, size, 0, &bp);
                }
                if (error) {
                        return (error);
                }
                n = MIN(n, size - bp->b_resid);

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

out:
        return (error);
}

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

        dp->d_name[dp->d_namlen] = 0;
        dp->d_reclen = _DIRENT_SIZE(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(dp, dp->d_reclen, idp->uio)) != 0)
                return (error);
        idp->uio_off = off;
        return (0);
}

int
iso_shipdir(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
                    || memcmp(sname, cname, sl)) {
                        if (idp->assocent.d_namlen) {
                                error = iso_uiodir(idp, &idp->assocent,
                                                   idp->assocoff);
                                if (error)
                                        return (error);
                                idp->assocent.d_namlen = 0;
                        }
                        if (idp->saveent.d_namlen) {
                                error = iso_uiodir(idp, &idp->saveent,
                                                   idp->saveoff);
                                if (error)
                                        return (error);
                                idp->saveent.d_namlen = 0;
                        }
                }
        }
        idp->current.d_reclen = _DIRENT_SIZE(&idp->current);
        if (assoc) {
                idp->assocoff = idp->curroff;
                memcpy(&idp->assocent, &idp->current, idp->current.d_reclen);
        } else {
                idp->saveoff = idp->curroff;
                memcpy(&idp->saveent, &idp->current, idp->current.d_reclen);
        }
        return (0);
}

/*
 * Vnode op for readdir
 */
int
cd9660_readdir(void *v)
{
        struct vop_readdir_args /* {
                struct vnode *a_vp;
                struct uio *a_uio;
                kauth_cred_t a_cred;
                int *a_eofflag;
                off_t **a_cookies;
                int *a_ncookies;
        } */ *ap = v;
        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;
        off_t *cookies = NULL;
        int ncookies = 0;

        if (vdp->v_type != VDIR)
                return (ENOTDIR);

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

        idp = malloc(sizeof(*idp), M_TEMP, M_WAITOK | M_ZERO);
        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 {
                ncookies = uio->uio_resid / _DIRENT_MINSIZE((struct dirent *)0);
                cookies = malloc(ncookies * sizeof(off_t), M_TEMP, M_WAITOK);
                idp->cookies = cookies;
                idp->ncookies = ncookies;
        }
        idp->eofflag = 1;
        idp->curroff = uio->uio_offset;

        if ((entryoffsetinblock = idp->curroff & bmask) &&
            (error = cd9660_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, 0);
                        error = cd9660_blkatoff(vdp, (off_t)idp->curroff,
                                             NULL, &bp);
                        if (error)
                                break;
                        entryoffsetinblock = 0;
                }
                /*
                 * Get pointer to next entry.
                 */
                KASSERT(bp != NULL);
                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 */
                        isofntrans(ep->name, idp->current.d_namlen,
                                   idp->current.d_name, &namelen,
                                   imp->iso_ftype == ISO_FTYPE_9660,
                                   (imp->im_flags & ISOFSMNT_NOCASETRANS) == 0,
                                   isonum_711(ep->flags)&4,
                                   imp->im_joliet_level);
                        switch (idp->current.d_name[0]) {
                        case 0:
                                idp->current.d_name[0] = '.';
                                idp->current.d_namlen = 1;
                                error = iso_uiodir(idp, &idp->current,
                                    idp->curroff);
                                break;
                        case 1:
                                strlcpy(idp->current.d_name, "..",
                                    sizeof(idp->current.d_name));
                                idp->current.d_namlen = 2;
                                error = iso_uiodir(idp, &idp->current,
                                    idp->curroff);
                                break;
                        default:
                                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, 0);

        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;

int
cd9660_readlink(void *v)
{
        struct vop_readlink_args /* {
                struct vnode *a_vp;
                struct uio *a_uio;
                kauth_cred_t a_cred;
        } */ *ap = v;
        ISONODE *ip;
        ISODIR  *dirp;
        ISOMNT  *imp;
        struct  buf *bp;
        struct  uio *uio;
        u_short symlen;
        int     error;
        char    *symname;
        bool use_pnbuf;

        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, 0, &bp);
        if (error) {
                return (EINVAL);
        }

        /*
         * Setup the directory pointer for this inode
         */
        dirp = (ISODIR *)((char *)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)
            > imp->logical_block_size) {
                brelse(bp, 0);
                return (EINVAL);
        }

        /*
         * Now get a buffer
         * Abuse a namei buffer for now.
         */
        use_pnbuf = !VMSPACE_IS_KERNEL_P(uio->uio_vmspace) ||
            uio->uio_iov->iov_len < MAXPATHLEN;
        if (use_pnbuf) {
                symname = PNBUF_GET();
        } else {
                symname = uio->uio_iov->iov_base;
        }

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

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

/*
 * Calculate the logical to physical mapping if not done already,
 * then call the device strategy routine.
 */
int
cd9660_strategy(void *v)
{
        struct vop_strategy_args /* {
                struct vnode *a_vp;
                struct buf *a_bp;
        } */ *ap = v;
        struct buf *bp = ap->a_bp;
        struct vnode *vp = ap->a_vp;
        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) {
                error = VOP_BMAP(vp, bp->b_lblkno, NULL, &bp->b_blkno, NULL);
                if (error) {
                        bp->b_error = 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_mnt->im_devvp;
        return (VOP_STRATEGY(vp, bp));
}

/*
 * Print out the contents of an inode.
 */
/*ARGSUSED*/
int
cd9660_print(void *v)
{

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

/*
 * Return POSIX pathconf information applicable to cd9660 filesystems.
 */
int
cd9660_pathconf(void *v)
{
        struct vop_pathconf_args /* {
                struct vnode *a_vp;
                int a_name;
                register_t *a_retval;
        } */ *ap = v;
        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 = ISO_MAXNAMLEN;
                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);
        case _PC_SYNC_IO:
                *ap->a_retval = 1;
                return (0);
        case _PC_FILESIZEBITS:
                *ap->a_retval = 32;
                return (0);
        default:
                return genfs_pathconf(ap);
        }
        /* NOTREACHED */
}

/*
 * Allow changing the size for special files (and fifos).
 */
int
cd9660_setattr(void *v)
{
        struct vop_setattr_args /* {
                struct vnodeop_desc *a_desc;
                struct vnode *a_vp;
                struct vattr *a_vap;
                kauth_cred_t a_cred;
                struct proc *a_p;
        } */ *ap = v;
        struct vattr *vap = ap->a_vap;
        struct vnode *vp = ap->a_vp;

        /*
         * Only size is changeable.
         */
        if (vap->va_type != VNON
            || vap->va_nlink != (nlink_t)VNOVAL
            || vap->va_fsid != VNOVAL
            || vap->va_fileid != VNOVAL
            || vap->va_blocksize != VNOVAL
            || vap->va_rdev != (dev_t)VNOVAL
            || (int)vap->va_bytes != VNOVAL
            || vap->va_gen != VNOVAL
            || vap->va_flags != 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 EOPNOTSUPP;

        if (vap->va_size != VNOVAL
            && vp->v_type != VCHR
            && vp->v_type != VBLK
            && vp->v_type != VFIFO)
                return EOPNOTSUPP;

        return 0;
}

/*
 * Global vfs data structures for cd9660
 */
int (**cd9660_vnodeop_p)(void *);
const struct vnodeopv_entry_desc cd9660_vnodeop_entries[] = {
        { &vop_default_desc, vn_default_error },
        { &vop_parsepath_desc, genfs_parsepath },       /* parsepath */
        { &vop_lookup_desc, cd9660_lookup },            /* lookup */
        { &vop_create_desc, genfs_eopnotsupp },         /* create */
        { &vop_mknod_desc, genfs_eopnotsupp },          /* mknod */
        { &vop_open_desc, genfs_nullop },               /* open */
        { &vop_close_desc, genfs_nullop },              /* close */
        { &vop_access_desc, cd9660_access },            /* access */
        { &vop_accessx_desc, genfs_accessx },           /* accessx */
        { &vop_getattr_desc, cd9660_getattr },          /* getattr */
        { &vop_setattr_desc, cd9660_setattr },          /* setattr */
        { &vop_read_desc, cd9660_read },                /* read */
        { &vop_write_desc, genfs_eopnotsupp },          /* write */
        { &vop_fallocate_desc, genfs_eopnotsupp },      /* fallocate */
        { &vop_fdiscard_desc, genfs_eopnotsupp },       /* fdiscard */
        { &vop_fcntl_desc, genfs_fcntl },               /* fcntl */
        { &vop_ioctl_desc, genfs_enoioctl },            /* ioctl */
        { &vop_poll_desc, genfs_poll },                 /* poll */
        { &vop_revoke_desc, genfs_revoke },             /* revoke */
        { &vop_mmap_desc, genfs_mmap },                 /* mmap */
        { &vop_fsync_desc, genfs_nullop },              /* fsync */
        { &vop_seek_desc, genfs_seek },                 /* seek */
        { &vop_remove_desc, genfs_eopnotsupp },         /* remove */
        { &vop_link_desc, genfs_erofs_link },           /* link */
        { &vop_rename_desc, genfs_eopnotsupp },         /* rename */
        { &vop_mkdir_desc, genfs_eopnotsupp },          /* mkdir */
        { &vop_rmdir_desc, genfs_eopnotsupp },          /* rmdir */
        { &vop_symlink_desc, genfs_erofs_symlink },     /* symlink */
        { &vop_readdir_desc, cd9660_readdir },          /* readdir */
        { &vop_readlink_desc, cd9660_readlink },        /* readlink */
        { &vop_abortop_desc, genfs_abortop },           /* abortop */
        { &vop_inactive_desc, cd9660_inactive },        /* inactive */
        { &vop_reclaim_desc, cd9660_reclaim },          /* reclaim */
        { &vop_lock_desc, genfs_lock },                 /* lock */
        { &vop_unlock_desc, genfs_unlock },             /* unlock */
        { &vop_bmap_desc, cd9660_bmap },                /* bmap */
        { &vop_strategy_desc, cd9660_strategy },        /* strategy */
        { &vop_print_desc, cd9660_print },              /* print */
        { &vop_islocked_desc, genfs_islocked },         /* islocked */
        { &vop_pathconf_desc, cd9660_pathconf },        /* pathconf */
        { &vop_advlock_desc, genfs_einval },            /* advlock */
        { &vop_bwrite_desc, vn_bwrite },                /* bwrite */
        { &vop_getpages_desc, genfs_getpages },         /* getpages */
        { &vop_putpages_desc, genfs_putpages },         /* putpages */
        { NULL, NULL }
};
const struct vnodeopv_desc cd9660_vnodeop_opv_desc =
        { &cd9660_vnodeop_p, cd9660_vnodeop_entries };

/*
 * Special device vnode ops
 */
int (**cd9660_specop_p)(void *);
const struct vnodeopv_entry_desc cd9660_specop_entries[] = {
        { &vop_default_desc, vn_default_error },
        GENFS_SPECOP_ENTRIES,
        { &vop_close_desc, spec_close },                /* close */
        { &vop_access_desc, cd9660_access },            /* access */
        { &vop_accessx_desc, genfs_accessx },           /* accessx */
        { &vop_getattr_desc, cd9660_getattr },          /* getattr */
        { &vop_setattr_desc, cd9660_setattr },          /* setattr */
        { &vop_read_desc, spec_read },                  /* read */
        { &vop_write_desc, spec_write },                /* write */
        { &vop_fcntl_desc, genfs_fcntl },               /* fcntl */
        { &vop_fsync_desc, spec_fsync },                /* fsync */
        { &vop_inactive_desc, cd9660_inactive },        /* inactive */
        { &vop_reclaim_desc, cd9660_reclaim },          /* reclaim */
        { &vop_lock_desc, genfs_lock },                 /* lock */
        { &vop_unlock_desc, genfs_unlock },             /* unlock */
        { &vop_print_desc, cd9660_print },              /* print */
        { &vop_islocked_desc, genfs_islocked },         /* islocked */
        { &vop_bwrite_desc, vn_bwrite },                /* bwrite */
        { NULL, NULL }
};
const struct vnodeopv_desc cd9660_specop_opv_desc =
        { &cd9660_specop_p, cd9660_specop_entries };

int (**cd9660_fifoop_p)(void *);
const struct vnodeopv_entry_desc cd9660_fifoop_entries[] = {
        { &vop_default_desc, vn_default_error },
        GENFS_FIFOOP_ENTRIES,
        { &vop_close_desc, vn_fifo_bypass },            /* close */
        { &vop_access_desc, cd9660_access },            /* access */
        { &vop_accessx_desc, genfs_accessx },           /* accessx */
        { &vop_getattr_desc, cd9660_getattr },          /* getattr */
        { &vop_setattr_desc, cd9660_setattr },          /* setattr */
        { &vop_read_desc, vn_fifo_bypass },             /* read */
        { &vop_write_desc, vn_fifo_bypass },            /* write */
        { &vop_fcntl_desc, genfs_fcntl },               /* fcntl */
        { &vop_fsync_desc, vn_fifo_bypass },            /* fsync */
        { &vop_inactive_desc, cd9660_inactive },        /* inactive */
        { &vop_reclaim_desc, cd9660_reclaim },          /* reclaim */
        { &vop_lock_desc, genfs_lock },                 /* lock */
        { &vop_unlock_desc, genfs_unlock },             /* unlock */
        { &vop_strategy_desc, vn_fifo_bypass },         /* strategy */
        { &vop_print_desc, cd9660_print },              /* print */
        { &vop_islocked_desc, genfs_islocked },         /* islocked */
        { &vop_bwrite_desc, vn_bwrite },                /* bwrite */
        { NULL, NULL }
};
const struct vnodeopv_desc cd9660_fifoop_opv_desc =
        { &cd9660_fifoop_p, cd9660_fifoop_entries };