nfs_vnops.c   [plain text]

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * Copyright (c) 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rick Macklem at The University of Guelph.
 *
 * 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.
 *
 *	@(#)nfs_vnops.c	8.16 (Berkeley) 5/27/95
 * FreeBSD-Id: nfs_vnops.c,v 1.72 1997/11/07 09:20:48 phk Exp $
 */


/*
 * vnode op calls for Sun NFS version 2 and 3
 */

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/resourcevar.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/conf.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/dirent.h>
#include <sys/fcntl.h>
#include <sys/lockf.h>
#include <sys/ubc.h>

#include <ufs/ufs/dir.h>
#include <vfs/vfs_support.h>

#include <sys/vm.h>
#include <machine/spl.h>
#include <vm/vm_pageout.h>

#include <sys/time.h> 
#include <kern/clock.h>

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

#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <nfs/nfsnode.h>
#include <nfs/nfsmount.h>
#include <nfs/xdr_subs.h>
#include <nfs/nfsm_subs.h>
#include <nfs/nqnfs.h>

#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <kern/task.h>
#include <vm/vm_kern.h>

#include <sys/kdebug.h>

#define	TRUE	1
#define	FALSE	0

static int	nfsspec_read __P((struct vop_read_args *));
static int	nfsspec_write __P((struct vop_write_args *));
static int	nfsfifo_read __P((struct vop_read_args *));
static int	nfsfifo_write __P((struct vop_write_args *));
static int	nfsspec_close __P((struct vop_close_args *));
static int	nfsfifo_close __P((struct vop_close_args *));
#define nfs_poll vop_nopoll
static int	nfs_ioctl __P((struct vop_ioctl_args *));
static int	nfs_select __P((struct vop_select_args *));
static int	nfs_flush __P((struct vnode *,struct ucred *,int,struct proc *,int));
static int	nfs_setattrrpc __P((struct vnode *,struct vattr *,struct ucred *,struct proc *));
static	int	nfs_lookup __P((struct vop_lookup_args *));
static	int	nfs_create __P((struct vop_create_args *));
static	int	nfs_mknod __P((struct vop_mknod_args *));
static	int	nfs_open __P((struct vop_open_args *));
static	int	nfs_close __P((struct vop_close_args *));
static	int	nfs_access __P((struct vop_access_args *));
static	int	nfs_getattr __P((struct vop_getattr_args *));
static	int	nfs_setattr __P((struct vop_setattr_args *));
static	int	nfs_read __P((struct vop_read_args *));
static	int	nfs_mmap __P((struct vop_mmap_args *));
static	int	nfs_fsync __P((struct vop_fsync_args *));
static	int	nfs_remove __P((struct vop_remove_args *));
static	int	nfs_link __P((struct vop_link_args *));
static	int	nfs_rename __P((struct vop_rename_args *));
static	int	nfs_mkdir __P((struct vop_mkdir_args *));
static	int	nfs_rmdir __P((struct vop_rmdir_args *));
static	int	nfs_symlink __P((struct vop_symlink_args *));
static	int	nfs_readdir __P((struct vop_readdir_args *));
static	int	nfs_bmap __P((struct vop_bmap_args *));
static	int	nfs_strategy __P((struct vop_strategy_args *));
static	int	nfs_lookitup __P((struct vnode *,char *,int,struct ucred *,struct proc *,struct nfsnode **));
static	int	nfs_sillyrename __P((struct vnode *,struct vnode *,struct componentname *));
static int	nfsspec_access __P((struct vop_access_args *));
static int	nfs_readlink __P((struct vop_readlink_args *));
static int	nfs_print __P((struct vop_print_args *));
static int	nfs_pathconf __P((struct vop_pathconf_args *));
static int	nfs_advlock __P((struct vop_advlock_args *));
static int	nfs_blkatoff __P((struct vop_blkatoff_args *));
static int	nfs_bwrite __P((struct vop_bwrite_args *));
static int	nfs_valloc __P((struct vop_valloc_args *));
static int	nfs_vfree __P((struct vop_vfree_args *));
static int	nfs_truncate __P((struct vop_truncate_args *));
static int	nfs_update __P((struct vop_update_args *));
static	int	nfs_pagein __P((struct vop_pagein_args *));
static	int	nfs_pageout __P((struct vop_pageout_args *));
static	int nfs_blktooff __P((struct vop_blktooff_args *));
static	int nfs_offtoblk __P((struct vop_offtoblk_args *));
static	int nfs_cmap __P((struct vop_cmap_args *));

/*
 * Global vfs data structures for nfs
 */
vop_t **nfsv2_vnodeop_p;
static struct vnodeopv_entry_desc nfsv2_vnodeop_entries[] = {
	{ &vop_default_desc, (vop_t *)vn_default_error },
	{ &vop_lookup_desc, (vop_t *)nfs_lookup },	/* lookup */
	{ &vop_create_desc, (vop_t *)nfs_create },	/* create */
	{ &vop_mknod_desc, (vop_t *)nfs_mknod },	/* mknod */
	{ &vop_open_desc, (vop_t *)nfs_open },		/* open */
	{ &vop_close_desc, (vop_t *)nfs_close },	/* close */
	{ &vop_access_desc, (vop_t *)nfs_access },	/* access */
	{ &vop_getattr_desc, (vop_t *)nfs_getattr },	/* getattr */
	{ &vop_setattr_desc, (vop_t *)nfs_setattr },	/* setattr */
	{ &vop_read_desc, (vop_t *)nfs_read },		/* read */
	{ &vop_write_desc, (vop_t *)nfs_write },	/* write */
	{ &vop_lease_desc, (vop_t *)nfs_lease_check },	/* lease */
	{ &vop_ioctl_desc, (vop_t *)nfs_ioctl },	/* ioctl */
	{ &vop_select_desc, (vop_t *)nfs_select },	/* select */
	{ &vop_revoke_desc, (vop_t *)nfs_revoke },	/* revoke */
	{ &vop_mmap_desc, (vop_t *)nfs_mmap },		/* mmap */
	{ &vop_fsync_desc, (vop_t *)nfs_fsync },	/* fsync */
	{ &vop_seek_desc, (vop_t *)nfs_seek },		/* seek */
	{ &vop_remove_desc, (vop_t *)nfs_remove },	/* remove */
	{ &vop_link_desc, (vop_t *)nfs_link },		/* link */
	{ &vop_rename_desc, (vop_t *)nfs_rename },	/* rename */
	{ &vop_mkdir_desc, (vop_t *)nfs_mkdir },	/* mkdir */
	{ &vop_rmdir_desc, (vop_t *)nfs_rmdir },	/* rmdir */
	{ &vop_symlink_desc, (vop_t *)nfs_symlink },	/* symlink */
	{ &vop_readdir_desc, (vop_t *)nfs_readdir },	/* readdir */
	{ &vop_readlink_desc, (vop_t *)nfs_readlink },	/* readlink */
	{ &vop_abortop_desc, (vop_t *)nfs_abortop },	/* abortop */
	{ &vop_inactive_desc, (vop_t *)nfs_inactive },	/* inactive */
	{ &vop_reclaim_desc, (vop_t *)nfs_reclaim },	/* reclaim */
	{ &vop_lock_desc, (vop_t *)nfs_lock },		/* lock */
	{ &vop_unlock_desc, (vop_t *)nfs_unlock },	/* unlock */
	{ &vop_bmap_desc, (vop_t *)nfs_bmap },		/* bmap */
	{ &vop_strategy_desc, (vop_t *)nfs_strategy },	/* strategy */
	{ &vop_print_desc, (vop_t *)nfs_print },	/* print */
	{ &vop_islocked_desc, (vop_t *)nfs_islocked },	/* islocked */
	{ &vop_pathconf_desc, (vop_t *)nfs_pathconf },	/* pathconf */
	{ &vop_advlock_desc, (vop_t *)nfs_advlock },	/* advlock */
	{ &vop_blkatoff_desc, (vop_t *)nfs_blkatoff },	/* blkatoff */
	{ &vop_valloc_desc, (vop_t *)nfs_valloc },	/* valloc */
	{ &vop_reallocblks_desc, (vop_t *)nfs_reallocblks },	/* reallocblks */
	{ &vop_vfree_desc, (vop_t *)nfs_vfree },	/* vfree */
	{ &vop_truncate_desc, (vop_t *)nfs_truncate },	/* truncate */
	{ &vop_update_desc, (vop_t *)nfs_update },	/* update */
	{ &vop_bwrite_desc, (vop_t *)nfs_bwrite },	/* bwrite */
	{ &vop_pagein_desc, (vop_t *)nfs_pagein },		/* Pagein */
	{ &vop_pageout_desc, (vop_t *)nfs_pageout },		/* Pageout */
	{ &vop_copyfile_desc, (vop_t *)err_copyfile },		/* Copyfile */
	{ &vop_blktooff_desc, (vop_t *)nfs_blktooff },		/* blktooff */
	{ &vop_offtoblk_desc, (vop_t *)nfs_offtoblk },		/* offtoblk */
	{ &vop_cmap_desc, (vop_t *)nfs_cmap },		/* cmap */
	{ NULL, NULL }
};
struct vnodeopv_desc nfsv2_vnodeop_opv_desc =
	{ &nfsv2_vnodeop_p, nfsv2_vnodeop_entries };
#ifdef __FreeBSD__
VNODEOP_SET(nfsv2_vnodeop_opv_desc);
#endif

/*
 * Special device vnode ops
 */
vop_t **spec_nfsv2nodeop_p;
static struct vnodeopv_entry_desc spec_nfsv2nodeop_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 *)nfsspec_close },	/* close */
	{ &vop_access_desc, (vop_t *)nfsspec_access },	/* access */
	{ &vop_getattr_desc, (vop_t *)nfs_getattr },	/* getattr */
	{ &vop_setattr_desc, (vop_t *)nfs_setattr },	/* setattr */
	{ &vop_read_desc, (vop_t *)nfsspec_read },	/* read */
	{ &vop_write_desc, (vop_t *)nfsspec_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 *)nfs_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 *)nfs_inactive },	/* inactive */
	{ &vop_reclaim_desc, (vop_t *)nfs_reclaim },	/* reclaim */
	{ &vop_lock_desc, (vop_t *)nfs_lock },		/* lock */
	{ &vop_unlock_desc, (vop_t *)nfs_unlock },	/* unlock */
	{ &vop_bmap_desc, (vop_t *)spec_bmap },		/* bmap */
	{ &vop_strategy_desc, (vop_t *)spec_strategy },	/* strategy */
	{ &vop_print_desc, (vop_t *)nfs_print },	/* print */
	{ &vop_islocked_desc, (vop_t *)nfs_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_reallocblks_desc, (vop_t *)spec_reallocblks },	/* reallocblks */
	{ &vop_vfree_desc, (vop_t *)spec_vfree },	/* vfree */
	{ &vop_truncate_desc, (vop_t *)spec_truncate },	/* truncate */
	{ &vop_update_desc, (vop_t *)nfs_update },	/* update */
	{ &vop_bwrite_desc, (vop_t *)vn_bwrite },	/* bwrite */
	{ &vop_devblocksize_desc, (vop_t *)spec_devblocksize },  /* devblocksize */
	{ &vop_pagein_desc, (vop_t *)nfs_pagein },		/* Pagein */
	{ &vop_pageout_desc, (vop_t *)nfs_pageout },		/* Pageout */
	{ &vop_blktooff_desc, (vop_t *)nfs_blktooff },		/* blktooff */
	{ &vop_offtoblk_desc, (vop_t *)nfs_offtoblk },		/* offtoblk */
	{ &vop_cmap_desc, (vop_t *)nfs_cmap },		/* cmap */
	{ NULL, NULL }
};
struct vnodeopv_desc spec_nfsv2nodeop_opv_desc =
	{ &spec_nfsv2nodeop_p, spec_nfsv2nodeop_entries };
#ifdef __FreeBSD__
VNODEOP_SET(spec_nfsv2nodeop_opv_desc);
#endif

vop_t **fifo_nfsv2nodeop_p;
static struct vnodeopv_entry_desc fifo_nfsv2nodeop_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 *)nfsfifo_close },	/* close */
	{ &vop_access_desc, (vop_t *)nfsspec_access },	/* access */
	{ &vop_getattr_desc, (vop_t *)nfs_getattr },	/* getattr */
	{ &vop_setattr_desc, (vop_t *)nfs_setattr },	/* setattr */
	{ &vop_read_desc, (vop_t *)nfsfifo_read },	/* read */
	{ &vop_write_desc, (vop_t *)nfsfifo_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 *)nfs_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 *)nfs_inactive },	/* inactive */
	{ &vop_reclaim_desc, (vop_t *)nfs_reclaim },	/* reclaim */
	{ &vop_lock_desc, (vop_t *)nfs_lock },		/* lock */
	{ &vop_unlock_desc, (vop_t *)nfs_unlock },	/* unlock */
	{ &vop_bmap_desc, (vop_t *)fifo_bmap },		/* bmap */
	{ &vop_strategy_desc, (vop_t *)fifo_badop },	/* strategy */
	{ &vop_print_desc, (vop_t *)nfs_print },	/* print */
	{ &vop_islocked_desc, (vop_t *)nfs_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_reallocblks_desc, (vop_t *)fifo_reallocblks },	/* reallocblks */
	{ &vop_vfree_desc, (vop_t *)fifo_vfree },	/* vfree */
	{ &vop_truncate_desc, (vop_t *)fifo_truncate },	/* truncate */
	{ &vop_update_desc, (vop_t *)nfs_update },	/* update */
	{ &vop_bwrite_desc, (vop_t *)vn_bwrite },	/* bwrite */
	{ &vop_pagein_desc, (vop_t *)nfs_pagein },		/* Pagein */
	{ &vop_pageout_desc, (vop_t *)nfs_pageout },		/* Pageout */
	{ &vop_blktooff_desc, (vop_t *)nfs_blktooff },		/* blktooff */
	{ &vop_offtoblk_desc, (vop_t *)nfs_offtoblk },		/* offtoblk */
	{ &vop_cmap_desc, (vop_t *)nfs_cmap },		/* cmap */
	{ NULL, NULL }
};
struct vnodeopv_desc fifo_nfsv2nodeop_opv_desc =
	{ &fifo_nfsv2nodeop_p, fifo_nfsv2nodeop_entries };
#ifdef __FreeBSD__
VNODEOP_SET(fifo_nfsv2nodeop_opv_desc);
#endif

static int	nfs_commit __P((struct vnode *vp, u_quad_t offset, int cnt,
				struct ucred *cred, struct proc *procp));
static int	nfs_mknodrpc __P((struct vnode *dvp, struct vnode **vpp,
				  struct componentname *cnp,
				  struct vattr *vap));
static int	nfs_removerpc __P((struct vnode *dvp, char *name, int namelen,
				   struct ucred *cred, struct proc *proc));
static int	nfs_renamerpc __P((struct vnode *fdvp, char *fnameptr,
				   int fnamelen, struct vnode *tdvp,
				   char *tnameptr, int tnamelen,
				   struct ucred *cred, struct proc *proc));
static int	nfs_renameit __P((struct vnode *sdvp,
				  struct componentname *scnp,
				  struct sillyrename *sp));

/*
 * Global variables
 */
extern u_long nfs_true, nfs_false;
extern struct nfsstats nfsstats;
extern nfstype nfsv3_type[9];
struct proc *nfs_iodwant[NFS_MAXASYNCDAEMON];
struct nfsmount *nfs_iodmount[NFS_MAXASYNCDAEMON];
int nfs_numasync = 0;
#define	DIRHDSIZ	(sizeof (struct dirent) - (MAXNAMLEN + 1))

static int	nfsaccess_cache_timeout = NFS_MAXATTRTIMO;
/* SYSCTL_INT(_vfs_nfs, OID_AUTO, access_cache_timeout, CTLFLAG_RW,
           &nfsaccess_cache_timeout, 0, "NFS ACCESS cache timeout");
*/
#define	NFSV3ACCESS_ALL (NFSV3ACCESS_READ | NFSV3ACCESS_MODIFY		\
			 | NFSV3ACCESS_EXTEND | NFSV3ACCESS_EXECUTE	\
			 | NFSV3ACCESS_DELETE | NFSV3ACCESS_LOOKUP)
                         
                         

static int
nfs3_access_otw(struct vnode *vp,  
                int wmode,
                struct proc *p,
                struct ucred *cred)  
{
        const int v3 = 1;
        u_int32_t *tl;
        int error = 0, attrflag;

        struct mbuf *mreq, *mrep, *md, *mb, *mb2;
        caddr_t bpos, dpos, cp2;
        register int32_t t1, t2;
        register caddr_t cp;
        u_int32_t rmode;
        struct nfsnode *np = VTONFS(vp);

        nfsstats.rpccnt[NFSPROC_ACCESS]++;   
        nfsm_reqhead(vp, NFSPROC_ACCESS, NFSX_FH(v3) + NFSX_UNSIGNED);
        nfsm_fhtom(vp, v3);
        nfsm_build(tl, u_int32_t *, NFSX_UNSIGNED);
        *tl = txdr_unsigned(wmode);
        nfsm_request(vp, NFSPROC_ACCESS, p, cred);
        nfsm_postop_attr(vp, attrflag);
        if (!error) {
                nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED);
                rmode = fxdr_unsigned(u_int32_t, *tl);
                np->n_mode = rmode;
                np->n_modeuid = cred->cr_uid;
                np->n_modestamp = time_second;
        }
        nfsm_reqdone;
        return error;
}

/*
 * nfs access vnode op.
 * For nfs version 2, just return ok. File accesses may fail later.
 * For nfs version 3, use the access rpc to check accessibility. If file modes
 * are changed on the server, accesses might still fail later.
 */
static int
nfs_access(ap)
	struct vop_access_args /* {
		struct vnode *a_vp;
		int  a_mode;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
        int error = 0;
        u_long mode, wmode;
	int v3 = NFS_ISV3(vp);
        struct nfsnode *np = VTONFS(vp);

	/*
	 * For nfs v3, do an access rpc, otherwise you are stuck emulating
	 * ufs_access() locally using the vattr. This may not be correct,
	 * since the server may apply other access criteria such as
	 * client uid-->server uid mapping that we do not know about, but
	 * this is better than just returning anything that is lying about
	 * in the cache.
	 */
	if (v3) {
		if (ap->a_mode & VREAD)
			mode = NFSV3ACCESS_READ;
		else
			mode = 0;
		if (vp->v_type == VDIR) {
			if (ap->a_mode & VWRITE)
				mode |= (NFSV3ACCESS_MODIFY | NFSV3ACCESS_EXTEND |
					 NFSV3ACCESS_DELETE);
			if (ap->a_mode & VEXEC)
				mode |= NFSV3ACCESS_LOOKUP;
		} else {
			if (ap->a_mode & VWRITE)
				mode |= (NFSV3ACCESS_MODIFY | NFSV3ACCESS_EXTEND);
			if (ap->a_mode & VEXEC)
				mode |= NFSV3ACCESS_EXECUTE;
		}
                /* XXX safety belt, only make blanket request if caching */
                if (nfsaccess_cache_timeout > 0) {
                        wmode = NFSV3ACCESS_READ | NFSV3ACCESS_MODIFY |
                                NFSV3ACCESS_EXTEND | NFSV3ACCESS_EXECUTE |
                                NFSV3ACCESS_DELETE | NFSV3ACCESS_LOOKUP;
                } else {
                        wmode = mode;
                }
                
                /*
                 * Does our cached result allow us to give a definite yes to
                 * this request?
                 */     
                if ((time_second < (np->n_modestamp + nfsaccess_cache_timeout)) &&
                    (ap->a_cred->cr_uid == np->n_modeuid) &&
                    ((np->n_mode & mode) == mode)) {
                        /* nfsstats.accesscache_hits++; */
                } else {
                        /*
                         * Either a no, or a don't know.  Go to the wire.
                         */
                       /* nfsstats.accesscache_misses++; */
                       error = nfs3_access_otw(vp, wmode, ap->a_p,ap->a_cred);
                       if (!error) {
                            if ((np->n_mode & mode) != mode)
				error = EACCES;
                        }
                }
	} else
		return (nfsspec_access(ap)); /* NFSv2 case checks for EROFS here*/
	/* CSM - moved EROFS check down per NetBSD rev 1.71.  So you
	 * get the correct error value with layered filesystems. 
         * EKN - moved the return(error) below this so it does get called.*/
	/*
	 * Disallow write attempts on filesystems mounted read-only;
	 * unless the file is a socket, fifo, or a block or character
	 * device resident on the filesystem.
	 */
	if (!error && (ap->a_mode & VWRITE) && (vp->v_mount->mnt_flag & MNT_RDONLY)) {
		switch (vp->v_type) {
		case VREG: case VDIR: case VLNK:
			error = EROFS;
                default: 
                        break;
		}
	}
        return (error);
}

/*
 * nfs open vnode op
 * Check to see if the type is ok
 * and that deletion is not in progress.
 * For paged in text files, you will need to flush the page cache
 * if consistency is lost.
 */
/* ARGSUSED */
static int
nfs_open(ap)
	struct vop_open_args /* {
		struct vnode *a_vp;
		int  a_mode;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	struct nfsnode *np = VTONFS(vp);
	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
	struct vattr vattr;
	int error;

	if (vp->v_type != VREG && vp->v_type != VDIR && vp->v_type != VLNK)
{ printf("open eacces vtyp=%d\n",vp->v_type);
		return (EACCES);
}
	/*
	 * Get a valid lease. If cached data is stale, flush it.
	 */
	if (nmp->nm_flag & NFSMNT_NQNFS) {
		if (NQNFS_CKINVALID(vp, np, ND_READ)) {
		    do {
			error = nqnfs_getlease(vp, ND_READ, ap->a_cred,
			    ap->a_p);
		    } while (error == NQNFS_EXPIRED);
		    if (error)
			return (error);
		    if (np->n_lrev != np->n_brev ||
			(np->n_flag & NQNFSNONCACHE)) {
			if ((error = nfs_vinvalbuf(vp, V_SAVE, ap->a_cred,
				ap->a_p, 1)) == EINTR)
				return (error);
			np->n_brev = np->n_lrev;
		    }
		}
	} else {
		if (np->n_flag & NMODIFIED) {
			if ((error = nfs_vinvalbuf(vp, V_SAVE, ap->a_cred,
				ap->a_p, 1)) == EINTR)
				return (error);
			np->n_attrstamp = 0;
			if (vp->v_type == VDIR)
				np->n_direofoffset = 0;
			error = VOP_GETATTR(vp, &vattr, ap->a_cred, ap->a_p);
			if (error)
				return (error);
			np->n_mtime = vattr.va_mtime.tv_sec;
		} else {
			error = VOP_GETATTR(vp, &vattr, ap->a_cred, ap->a_p);
			if (error)
				return (error);
			if (np->n_mtime != vattr.va_mtime.tv_sec) {
				if (vp->v_type == VDIR)
					np->n_direofoffset = 0;
				if ((error = nfs_vinvalbuf(vp, V_SAVE,
					ap->a_cred, ap->a_p, 1)) == EINTR)
					return (error);
				np->n_mtime = vattr.va_mtime.tv_sec;
			}
		}
	}
	if ((nmp->nm_flag & NFSMNT_NQNFS) == 0)
		np->n_attrstamp = 0; /* For Open/Close consistency */
	return (0);
}

/*
 * nfs close vnode op
 * What an NFS client should do upon close after writing is a debatable issue.
 * Most NFS clients push delayed writes to the server upon close, basically for
 * two reasons:
 * 1 - So that any write errors may be reported back to the client process
 *     doing the close system call. By far the two most likely errors are
 *     NFSERR_NOSPC and NFSERR_DQUOT to indicate space allocation failure.
 * 2 - To put a worst case upper bound on cache inconsistency between
 *     multiple clients for the file.
 * There is also a consistency problem for Version 2 of the protocol w.r.t.
 * not being able to tell if other clients are writing a file concurrently,
 * since there is no way of knowing if the changed modify time in the reply
 * is only due to the write for this client.
 * (NFS Version 3 provides weak cache consistency data in the reply that
 *  should be sufficient to detect and handle this case.)
 *
 * The current code does the following:
 * for NFS Version 2 - play it safe and flush/invalidate all dirty buffers
 * for NFS Version 3 - flush dirty buffers to the server but don't invalidate
 *                     or commit them (this satisfies 1 and 2 except for the
 *                     case where the server crashes after this close but
 *                     before the commit RPC, which is felt to be "good
 *                     enough". Changing the last argument to nfs_flush() to
 *                     a 1 would force a commit operation, if it is felt a
 *                     commit is necessary now.
 * for NQNFS         - do nothing now, since 2 is dealt with via leases and
 *                     1 should be dealt with via an fsync() system call for
 *                     cases where write errors are important.
 */
/* ARGSUSED */
static int
nfs_close(ap)
	struct vop_close_args /* {
		struct vnodeop_desc *a_desc;
		struct vnode *a_vp;
		int  a_fflag;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct nfsnode *np = VTONFS(vp);
	int error = 0;

	if (vp->v_type == VREG) {
#if DIAGNOSTIC
	    register struct sillyrename *sp = np->n_sillyrename;
	    if (sp)
                kprintf("nfs_close: %s, dvp=%x, vp=%x, ap=%x, np=%x, sp=%x\n",
                	&sp->s_name[0], (unsigned)(sp->s_dvp), (unsigned)vp,
                	(unsigned)ap, (unsigned)np, (unsigned)sp);
#endif
	    if ((VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NQNFS) == 0 &&
		(np->n_flag & NMODIFIED)) {
		if (NFS_ISV3(vp)) {
		    error = nfs_flush(vp, ap->a_cred, MNT_WAIT, ap->a_p, 0);
		    np->n_flag &= ~NMODIFIED;
		} else
		    error = nfs_vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 1);
		np->n_attrstamp = 0;
	    }
	    if (np->n_flag & NWRITEERR) {
		np->n_flag &= ~NWRITEERR;
		error = np->n_error;
	    }
	}
	return (error);
}

/*
 * nfs getattr call from vfs.
 */
static int
nfs_getattr(ap)
	struct vop_getattr_args /* {
		struct vnode *a_vp;
		struct vattr *a_vap;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct nfsnode *np = VTONFS(vp);
	register caddr_t cp;
	register u_long *tl;
	register int t1, t2;
	caddr_t bpos, dpos;
	int error = 0;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	int v3 = NFS_ISV3(vp);
	
	/*
	 * Update local times for special files.
	 */
	if (np->n_flag & (NACC | NUPD))
		np->n_flag |= NCHG;

	KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 513)) | DBG_FUNC_START,
		     (int)np->n_size, 0, (int)np->n_vattr.va_size, np->n_flag, 0);

	/*
	 * First look in the cache.
	 */
	if ((error = nfs_getattrcache(vp, ap->a_vap)) == 0) {
	        KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 513)) | DBG_FUNC_END,
			     (int)np->n_size, 0, (int)np->n_vattr.va_size, np->n_flag, 0);

		return (0);
	}
	if (error != ENOENT)
		return (error);
	error = 0;
        
	if (v3 && nfsaccess_cache_timeout > 0) {
		/*  nfsstats.accesscache_misses++; */
		if (error = nfs3_access_otw(vp, NFSV3ACCESS_ALL, ap->a_p, ap->a_cred))
                    return (error);
		if ((error = nfs_getattrcache(vp, ap->a_vap)) == 0)
			return (0);
		if (error != ENOENT)
			return (error);
		error = 0;
	}

	nfsstats.rpccnt[NFSPROC_GETATTR]++;
	nfsm_reqhead(vp, NFSPROC_GETATTR, NFSX_FH(v3));
	nfsm_fhtom(vp, v3);
	nfsm_request(vp, NFSPROC_GETATTR, ap->a_p, ap->a_cred);
	if (!error) {
		nfsm_loadattr(vp, ap->a_vap);
		if (np->n_mtime != ap->a_vap->va_mtime.tv_sec) {
			NFSTRACE(NFSTRC_GA_INV, vp);
			if (vp->v_type == VDIR)
				nfs_invaldir(vp);
			error = nfs_vinvalbuf(vp, V_SAVE, ap->a_cred,
					      ap->a_p, 1);
			if (!error) {
				NFSTRACE(NFSTRC_GA_INV1, vp);
				np->n_mtime = ap->a_vap->va_mtime.tv_sec;
			} else {
				NFSTRACE(NFSTRC_GA_INV2, error);
			}
		}
	}
	nfsm_reqdone;

	KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 513)) | DBG_FUNC_END,
		     (int)np->n_size, -1, (int)np->n_vattr.va_size, error, 0);

	return (error);
}

/*
 * nfs setattr call.
 */
static int
nfs_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;
{
	register struct vnode *vp = ap->a_vp;
	register struct nfsnode *np = VTONFS(vp);
	register struct vattr *vap = ap->a_vap;
	int error = 0;
	u_quad_t tsize;

#ifndef nolint
	tsize = (u_quad_t)0;
#endif
	/*
	 * Disallow write attempts if the filesystem is mounted read-only.
	 */
  	if ((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) &&
	    (vp->v_mount->mnt_flag & MNT_RDONLY))
		return (EROFS);
	if (vap->va_size != VNOVAL) {
 		switch (vp->v_type) {
 		case VDIR:
 			return (EISDIR);
 		case VCHR:
 		case VBLK:
 		case VSOCK:
 		case VFIFO:
			if (vap->va_mtime.tv_sec == VNOVAL &&
			    vap->va_atime.tv_sec == VNOVAL &&
			    vap->va_mode == (u_short)VNOVAL &&
			    vap->va_uid == (uid_t)VNOVAL &&
			    vap->va_gid == (gid_t)VNOVAL)
				return (0);
 			vap->va_size = VNOVAL;
 			break;
 		default:
			/*
			 * Disallow write attempts if the filesystem is
			 * mounted read-only.
			 */
			if (vp->v_mount->mnt_flag & MNT_RDONLY)
				return (EROFS);
			np->n_flag |= NMODIFIED;
 			tsize = np->n_size;
			
			KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 512)) | DBG_FUNC_START,
				     (int)np->n_size, (int)vap->va_size, (int)np->n_vattr.va_size, np->n_flag, 0);

 			if (vap->va_size == 0)
 				error = nfs_vinvalbuf(vp, 0,
 					ap->a_cred, ap->a_p, 1);
 			else
 				error = nfs_vinvalbuf(vp, V_SAVE,
 					ap->a_cred, ap->a_p, 1);

			if (UBCISVALID(vp))
				ubc_setsize(vp, (off_t)vap->va_size); /* XXX check error */

 			if (error) {
				printf("nfs_setattr: nfs_vinvalbuf %d\n", error);

#if DIAGNOSTIC
				kprintf("nfs_setattr: nfs_vinvalbuf %d\n",
					error);
#endif /* DIAGNOSTIC */
				if (UBCISVALID(vp))
				        ubc_setsize(vp, (off_t)tsize); /* XXX check error */

				KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 512)) | DBG_FUNC_END,
					     (int)np->n_size, (int)vap->va_size, (int)np->n_vattr.va_size, -1, 0);

 				return (error);
			}
			np->n_size = np->n_vattr.va_size = vap->va_size;

  		};
  	} else if ((vap->va_mtime.tv_sec != VNOVAL ||
		    vap->va_atime.tv_sec != VNOVAL) && (np->n_flag & NMODIFIED) &&
		   vp->v_type == VREG &&
		   (error = nfs_vinvalbuf(vp, V_SAVE, ap->a_cred,
					  ap->a_p, 1)) == EINTR)
	        return (error);

	error = nfs_setattrrpc(vp, vap, ap->a_cred, ap->a_p);

	KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 512)) | DBG_FUNC_END,
		     (int)np->n_size, (int)vap->va_size, (int)np->n_vattr.va_size, error, 0);

	if (error && vap->va_size != VNOVAL) {
		/* make every effort to resync file size w/ server... */
		int err = 0; /* preserve "error" for return */

		printf("nfs_setattr: nfs_setattrrpc %d\n", error);
#if DIAGNOSTIC
		kprintf("nfs_setattr: nfs_setattrrpc %d\n", error);
#endif /* DIAGNOSTIC */
		np->n_size = np->n_vattr.va_size = tsize;
		if (UBCISVALID(vp))
			ubc_setsize(vp, (off_t)np->n_size); /* XXX check error */
		vap->va_size = tsize;
		err = nfs_setattrrpc(vp, vap, ap->a_cred, ap->a_p);

		if (err)
			printf("nfs_setattr1: nfs_setattrrpc %d\n", err);
#if DIAGNOSTIC
		if (err)
			kprintf("nfs_setattr nfs_setattrrpc %d\n", err);
#endif /* DIAGNOSTIC */
	}
	return (error);
}

/*
 * Do an nfs setattr rpc.
 */
static int
nfs_setattrrpc(vp, vap, cred, procp)
	register struct vnode *vp;
	register struct vattr *vap;
	struct ucred *cred;
	struct proc *procp;
{
	register struct nfsv2_sattr *sp;
	register caddr_t cp;
	register long t1, t2;
	caddr_t bpos, dpos, cp2;
	u_long *tl;
	int error = 0, wccflag = NFSV3_WCCRATTR;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	int v3 = NFS_ISV3(vp);

	nfsstats.rpccnt[NFSPROC_SETATTR]++;
	nfsm_reqhead(vp, NFSPROC_SETATTR, NFSX_FH(v3) + NFSX_SATTR(v3));
	nfsm_fhtom(vp, v3);
	if (v3) {
		if (vap->va_mode != (u_short)VNOVAL) {
			nfsm_build(tl, u_long *, 2 * NFSX_UNSIGNED);
			*tl++ = nfs_true;
			*tl = txdr_unsigned(vap->va_mode);
		} else {
			nfsm_build(tl, u_long *, NFSX_UNSIGNED);
			*tl = nfs_false;
		}
		if (vap->va_uid != (uid_t)VNOVAL) {
			nfsm_build(tl, u_long *, 2 * NFSX_UNSIGNED);
			*tl++ = nfs_true;
			*tl = txdr_unsigned(vap->va_uid);
		} else {
			nfsm_build(tl, u_long *, NFSX_UNSIGNED);
			*tl = nfs_false;
		}
		if (vap->va_gid != (gid_t)VNOVAL) {
			nfsm_build(tl, u_long *, 2 * NFSX_UNSIGNED);
			*tl++ = nfs_true;
			*tl = txdr_unsigned(vap->va_gid);
		} else {
			nfsm_build(tl, u_long *, NFSX_UNSIGNED);
			*tl = nfs_false;
		}
		if (vap->va_size != VNOVAL) {
			nfsm_build(tl, u_long *, 3 * NFSX_UNSIGNED);
			*tl++ = nfs_true;
			txdr_hyper(&vap->va_size, tl);
		} else {
			nfsm_build(tl, u_long *, NFSX_UNSIGNED);
			*tl = nfs_false;
		}
		if (vap->va_atime.tv_sec != VNOVAL) {
			if (vap->va_atime.tv_sec != time.tv_sec) {
				nfsm_build(tl, u_long *, 3 * NFSX_UNSIGNED);
				*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
				txdr_nfsv3time(&vap->va_atime, tl);
			} else {
				nfsm_build(tl, u_long *, NFSX_UNSIGNED);
				*tl = txdr_unsigned(NFSV3SATTRTIME_TOSERVER);
			}
		} else {
			nfsm_build(tl, u_long *, NFSX_UNSIGNED);
			*tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
		}
		if (vap->va_mtime.tv_sec != VNOVAL) {
			if (vap->va_mtime.tv_sec != time.tv_sec) {
				nfsm_build(tl, u_long *, 3 * NFSX_UNSIGNED);
				*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
				txdr_nfsv3time(&vap->va_mtime, tl);
			} else {
				nfsm_build(tl, u_long *, NFSX_UNSIGNED);
				*tl = txdr_unsigned(NFSV3SATTRTIME_TOSERVER);
			}
		} else {
			nfsm_build(tl, u_long *, NFSX_UNSIGNED);
			*tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
		}
		nfsm_build(tl, u_long *, NFSX_UNSIGNED);
		*tl = nfs_false;
	} else {
		nfsm_build(sp, struct nfsv2_sattr *, NFSX_V2SATTR);
		if (vap->va_mode == (u_short)VNOVAL)
			sp->sa_mode = VNOVAL;
		else
			sp->sa_mode = vtonfsv2_mode(vp->v_type, vap->va_mode);
		if (vap->va_uid == (uid_t)VNOVAL)
			sp->sa_uid = VNOVAL;
		else
			sp->sa_uid = txdr_unsigned(vap->va_uid);
		if (vap->va_gid == (gid_t)VNOVAL)
			sp->sa_gid = VNOVAL;
		else
			sp->sa_gid = txdr_unsigned(vap->va_gid);
		sp->sa_size = txdr_unsigned(vap->va_size);
		txdr_nfsv2time(&vap->va_atime, &sp->sa_atime);
		txdr_nfsv2time(&vap->va_mtime, &sp->sa_mtime);
	}
	nfsm_request(vp, NFSPROC_SETATTR, procp, cred);
	if (v3) {
		nfsm_wcc_data(vp, wccflag);
        	if ((!wccflag) && (vp->v_type != VBAD)) /* EINVAL set on VBAD vnode */
                	VTONFS(vp)->n_attrstamp = 0;
	} else
		nfsm_loadattr(vp, (struct vattr *)0);
	nfsm_reqdone;
	return (error);
}

/*
 * nfs lookup call, one step at a time...
 * First look in cache
 * If not found, unlock the directory nfsnode and do the rpc
 */
static int
nfs_lookup(ap)
	struct vop_lookup_args /* {
		struct vnodeop_desc *a_desc;
		struct vnode *a_dvp;
		struct vnode **a_vpp;
		struct componentname *a_cnp;
	} */ *ap;
{
	register struct componentname *cnp = ap->a_cnp;
	register struct vnode *dvp = ap->a_dvp;
	register struct vnode **vpp = ap->a_vpp;
	register int flags = cnp->cn_flags;
	register struct vnode *newvp;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	struct nfsmount *nmp;
	caddr_t bpos, dpos, cp2;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	long len;
	nfsfh_t *fhp;
	struct nfsnode *np;
	int lockparent, wantparent, error = 0, attrflag, fhsize;
	int v3 = NFS_ISV3(dvp);
	struct proc *p = cnp->cn_proc;
        int worldbuildworkaround = 1;

	if ((flags & ISLASTCN) && (dvp->v_mount->mnt_flag & MNT_RDONLY) &&
	    (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
		return (EROFS);
	*vpp = NULLVP;
	if (dvp->v_type != VDIR)
		return (ENOTDIR);
	lockparent = flags & LOCKPARENT;
	wantparent = flags & (LOCKPARENT|WANTPARENT);
	nmp = VFSTONFS(dvp->v_mount);
	np = VTONFS(dvp);
        
        if (worldbuildworkaround) {
        /* temporary workaround for world builds to not have dvp go
            VBAD on during server calls in this routine. When
            the real ref counting problem is found take this out.
            Note if this was later and before the nfsm_request
            set up, the workaround did not work (NOTE other difference
            was I only put one VREF in that time. Thus it needs
            to be above the cache_lookup branch or with 2 VREFS. Not
            sure which. Can't play with world builds right now to see
            which.  VOP_ACCESS could also make it go to server.  - EKN */
            VREF(dvp);   /* hang on to this dvp - EKN */
            VREF(dvp);   /* hang on tight - EKN  */
        }

	if ((error = cache_lookup(dvp, vpp, cnp)) && error != ENOENT) {
		struct vattr vattr;
		int vpid;

		if ((error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, p))) {
			*vpp = NULLVP;
                        if (worldbuildworkaround) {
                            vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                            vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                        }
			return (error);
		}
                
                /* got to check to make sure the vnode didn't go away if access went to server */
                if ((*vpp)->v_type == VBAD) {
                       if (worldbuildworkaround) {
                            vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                            vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                        }
                        return(EINVAL);
                }

		newvp = *vpp;
		vpid = newvp->v_id;
		/*
		 * See the comment starting `Step through' in ufs/ufs_lookup.c
		 * for an explanation of the locking protocol
		 */
		if (dvp == newvp) {
			VREF(newvp);
			error = 0;
		} else if (flags & ISDOTDOT) {
			VOP_UNLOCK(dvp, 0, p);
			error = vget(newvp, LK_EXCLUSIVE, p);
			if (!error && lockparent && (flags & ISLASTCN))
				error = vn_lock(dvp, LK_EXCLUSIVE, p);
		} else {
			error = vget(newvp, LK_EXCLUSIVE, p);
			if (!lockparent || error || !(flags & ISLASTCN))
				VOP_UNLOCK(dvp, 0, p);
		}
		if (!error) {
			if (vpid == newvp->v_id) {
			   if (!VOP_GETATTR(newvp, &vattr, cnp->cn_cred, p)
			    && vattr.va_ctime.tv_sec == VTONFS(newvp)->n_ctime) {
				nfsstats.lookupcache_hits++;
				if (cnp->cn_nameiop != LOOKUP &&
				    (flags & ISLASTCN))
					cnp->cn_flags |= SAVENAME;
                                        
                                if (worldbuildworkaround) {
                                    vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                                    vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                                }
                                
				return (0);
			   }
			   cache_purge(newvp);
                        }
			vput(newvp);
			if (lockparent && dvp != newvp && (flags & ISLASTCN))
				VOP_UNLOCK(dvp, 0, p);
		}
		error = vn_lock(dvp, LK_EXCLUSIVE, p);
		*vpp = NULLVP;
		if (error) {
                        if (worldbuildworkaround) {
                            vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                            vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                        }
			return (error);
                }
	}
        
	/* 
         * Got to check to make sure the vnode didn't go away if VOP_GETATTR went to server
	 * or callers prior to this blocked and had it go VBAD.
         */
	if (dvp->v_type == VBAD) {                   
            if (worldbuildworkaround) {
                vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                vrele(dvp);  /* end of hanging on tight to dvp - EKN */
                }
            return(EINVAL);
        }

	error = 0;
	newvp = NULLVP;
	nfsstats.lookupcache_misses++;
	nfsstats.rpccnt[NFSPROC_LOOKUP]++;
	len = cnp->cn_namelen;
	nfsm_reqhead(dvp, NFSPROC_LOOKUP,
		NFSX_FH(v3) + NFSX_UNSIGNED + nfsm_rndup(len));
	nfsm_fhtom(dvp, v3);
	nfsm_strtom(cnp->cn_nameptr, len, NFS_MAXNAMLEN);
	nfsm_request(dvp, NFSPROC_LOOKUP, cnp->cn_proc, cnp->cn_cred);
        
        /* this two lines set dvp refcounts back to where they were
        * before we took extra 2 VREFS to avoid VBAD vnode on dvp
        * during server calls for world builds. Remove when real
        * fix is found. - EKN */
        if (worldbuildworkaround) {
            vrele(dvp);  /* end of hanging on tight to dvp - EKN */
            vrele(dvp);  /* end of hanging on tight to dvp - EKN */
            }

	if (error) {
		nfsm_postop_attr(dvp, attrflag);
		m_freem(mrep);
		goto nfsmout;
	}
	nfsm_getfh(fhp, fhsize, v3);

	/*
	 * Handle RENAME case...
	 */
	if (cnp->cn_nameiop == RENAME && wantparent && (flags & ISLASTCN)) {
		if (NFS_CMPFH(np, fhp, fhsize)) {
			m_freem(mrep);
			return (EISDIR);
		}
		if ((error = nfs_nget(dvp->v_mount, fhp, fhsize, &np))) {
			m_freem(mrep);
			return (error);
		}
		newvp = NFSTOV(np);
		if (v3) {
			nfsm_postop_attr(newvp, attrflag);
			nfsm_postop_attr(dvp, attrflag);
		} else
			nfsm_loadattr(newvp, (struct vattr *)0);
		*vpp = newvp;
		m_freem(mrep);
		cnp->cn_flags |= SAVENAME;
		if (!lockparent)
			VOP_UNLOCK(dvp, 0, p);
		return (0);
	}

	if (flags & ISDOTDOT) {
		VOP_UNLOCK(dvp, 0, p);
		error = nfs_nget(dvp->v_mount, fhp, fhsize, &np);
		if (error) {
			vn_lock(dvp, LK_EXCLUSIVE + LK_RETRY, p);
			return (error);
		}
		newvp = NFSTOV(np);
		if (lockparent && (flags & ISLASTCN) &&
		    (error = vn_lock(dvp, LK_EXCLUSIVE, p))) {
		    	vput(newvp);
			return (error);
		}
	} else if (NFS_CMPFH(np, fhp, fhsize)) {
		VREF(dvp);
		newvp = dvp;
	} else {
		if ((error = nfs_nget(dvp->v_mount, fhp, fhsize, &np))) {
			m_freem(mrep);
			return (error);
		}
		if (!lockparent || !(flags & ISLASTCN))
			VOP_UNLOCK(dvp, 0, p);
		newvp = NFSTOV(np);
	}
	if (v3) {
		nfsm_postop_attr(newvp, attrflag);
		nfsm_postop_attr(dvp, attrflag);
	} else
		nfsm_loadattr(newvp, (struct vattr *)0);
	if (cnp->cn_nameiop != LOOKUP && (flags & ISLASTCN))
		cnp->cn_flags |= SAVENAME;
	if ((cnp->cn_flags & MAKEENTRY) &&
	    (cnp->cn_nameiop != DELETE || !(flags & ISLASTCN))) {
		np->n_ctime = np->n_vattr.va_ctime.tv_sec;
		cache_enter(dvp, newvp, cnp);
	}
	*vpp = newvp;
	nfsm_reqdone;
	if (error) {
		if (newvp != NULLVP) {
			vrele(newvp);
			*vpp = NULLVP;
		}
		if ((cnp->cn_nameiop == CREATE || cnp->cn_nameiop == RENAME) &&
		    (flags & ISLASTCN) && error == ENOENT) {
			if (!lockparent)
				VOP_UNLOCK(dvp, 0, p);
			if (dvp->v_mount->mnt_flag & MNT_RDONLY)
				error = EROFS;
			else
				error = EJUSTRETURN;
		}
		if (cnp->cn_nameiop != LOOKUP && (flags & ISLASTCN))
			cnp->cn_flags |= SAVENAME;
	}
	return (error);
}

/*
 * nfs read call.
 * Just call nfs_bioread() to do the work.
 */
static int
nfs_read(ap)
	struct vop_read_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		int  a_ioflag;
		struct ucred *a_cred;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;

	if (vp->v_type != VREG)
		return (EPERM);
	return (nfs_bioread(vp, ap->a_uio, ap->a_ioflag, ap->a_cred, 0));
}

/*
 * nfs readlink call
 */
static int
nfs_readlink(ap)
	struct vop_readlink_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		struct ucred *a_cred;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;

	if (vp->v_type != VLNK)
		return (EPERM);
	return (nfs_bioread(vp, ap->a_uio, 0, ap->a_cred, 0));
}

/*
 * Do a readlink rpc.
 * Called by nfs_doio() from below the buffer cache.
 */
int
nfs_readlinkrpc(vp, uiop, cred)
	register struct vnode *vp;
	struct uio *uiop;
	struct ucred *cred;
{
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	caddr_t bpos, dpos, cp2;
	int error = 0, len, attrflag;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	int v3 = NFS_ISV3(vp);

	nfsstats.rpccnt[NFSPROC_READLINK]++;
	nfsm_reqhead(vp, NFSPROC_READLINK, NFSX_FH(v3));
	nfsm_fhtom(vp, v3);
	nfsm_request(vp, NFSPROC_READLINK, uiop->uio_procp, cred);
	if (v3)
		nfsm_postop_attr(vp, attrflag);
	if (!error) {
		nfsm_strsiz(len, NFS_MAXPATHLEN);
               if (len == NFS_MAXPATHLEN) {
                        struct nfsnode *np = VTONFS(vp);
#if DIAGNOSTIC
                        if (!np)
                                panic("nfs_readlinkrpc: null np");
#endif  
                        if (np->n_size && np->n_size < NFS_MAXPATHLEN)
                                len = np->n_size;
                }
		nfsm_mtouio(uiop, len);
	}
	nfsm_reqdone;
	return (error);
}

/*
 * nfs read rpc call
 * Ditto above
 */
int
nfs_readrpc(vp, uiop, cred)
	register struct vnode *vp;
	struct uio *uiop;
	struct ucred *cred;
{
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	caddr_t bpos, dpos, cp2;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	struct nfsmount *nmp;
	int error = 0, len, retlen, tsiz, eof, attrflag;
	int v3 = NFS_ISV3(vp);

#ifndef nolint
	eof = 0;
#endif
	nmp = VFSTONFS(vp->v_mount);
	tsiz = uiop->uio_resid;
        if (((u_int64_t)uiop->uio_offset + (unsigned int)tsiz > 0xffffffff) && !v3)
		return (EFBIG);
	while (tsiz > 0) {
		nfsstats.rpccnt[NFSPROC_READ]++;
		len = (tsiz > nmp->nm_rsize) ? nmp->nm_rsize : tsiz;
		nfsm_reqhead(vp, NFSPROC_READ, NFSX_FH(v3) + NFSX_UNSIGNED * 3);
		nfsm_fhtom(vp, v3);
		nfsm_build(tl, u_long *, NFSX_UNSIGNED * 3);
		if (v3) {
			txdr_hyper(&uiop->uio_offset, tl);
			*(tl + 2) = txdr_unsigned(len);
		} else {
			*tl++ = txdr_unsigned(uiop->uio_offset);
			*tl++ = txdr_unsigned(len);
			*tl = 0;
		}
		nfsm_request(vp, NFSPROC_READ, uiop->uio_procp, cred);
		if (v3) {
			nfsm_postop_attr(vp, attrflag);
			if (error) {
				m_freem(mrep);
				goto nfsmout;
			}
			nfsm_dissect(tl, u_long *, 2 * NFSX_UNSIGNED);
			eof = fxdr_unsigned(int, *(tl + 1));
		} else
			nfsm_loadattr(vp, (struct vattr *)0);
		nfsm_strsiz(retlen, nmp->nm_rsize);
		nfsm_mtouio(uiop, retlen);
		m_freem(mrep);
		tsiz -= retlen;
		if (v3) {
			if (eof || retlen == 0)
				tsiz = 0;
		} else if (retlen < len)
			tsiz = 0;
	}
nfsmout:
	return (error);
}

/*
 * nfs write call
 */
int
nfs_writerpc(vp, uiop, cred, iomode, must_commit)
	register struct vnode *vp;
	register struct uio *uiop;
	struct ucred *cred;
	int *iomode, *must_commit;
{
	register u_long *tl;
	register caddr_t cp;
	register int t1, t2, backup;
	caddr_t bpos, dpos, cp2;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
	int error = 0, len, tsiz, wccflag = NFSV3_WCCRATTR, rlen, commit;
	int v3 = NFS_ISV3(vp), committed = NFSV3WRITE_FILESYNC;

#if DIAGNOSTIC
	if (uiop->uio_iovcnt != 1)
		panic("nfs_writerpc: iovcnt > 1");
#endif
	*must_commit = 0;
	tsiz = uiop->uio_resid;
        if (((u_int64_t)uiop->uio_offset + (unsigned int)tsiz > 0xffffffff) && !v3)
		return (EFBIG);
	while (tsiz > 0) {
		nfsstats.rpccnt[NFSPROC_WRITE]++;
		len = (tsiz > nmp->nm_wsize) ? nmp->nm_wsize : tsiz;
		nfsm_reqhead(vp, NFSPROC_WRITE,
			NFSX_FH(v3) + 5 * NFSX_UNSIGNED + nfsm_rndup(len));
		nfsm_fhtom(vp, v3);
		if (v3) {
			nfsm_build(tl, u_long *, 5 * NFSX_UNSIGNED);
			txdr_hyper(&uiop->uio_offset, tl);
			tl += 2;
			*tl++ = txdr_unsigned(len);
			*tl++ = txdr_unsigned(*iomode);
		} else {
			nfsm_build(tl, u_long *, 4 * NFSX_UNSIGNED);
			*++tl = txdr_unsigned(uiop->uio_offset);
			tl += 2;
		}
		*tl = txdr_unsigned(len);
		nfsm_uiotom(uiop, len);
		nfsm_request(vp, NFSPROC_WRITE, uiop->uio_procp, cred);
		if (v3) {
			wccflag = NFSV3_WCCCHK;
			nfsm_wcc_data(vp, wccflag);
			if (!error) {
				nfsm_dissect(tl, u_long *, 2 * NFSX_UNSIGNED +
					NFSX_V3WRITEVERF);
				rlen = fxdr_unsigned(int, *tl++);
				if (rlen <= 0) {
					error = NFSERR_IO;
					break;
				} else if (rlen < len) {
					backup = len - rlen;
					uiop->uio_iov->iov_base -= backup;
					uiop->uio_iov->iov_len += backup;
					uiop->uio_offset -= backup;
					uiop->uio_resid += backup;
					len = rlen;
				}
				commit = fxdr_unsigned(int, *tl++);

				/*
				 * Return the lowest committment level
				 * obtained by any of the RPCs.
				 */
				if (committed == NFSV3WRITE_FILESYNC)
					committed = commit;
				else if (committed == NFSV3WRITE_DATASYNC &&
					commit == NFSV3WRITE_UNSTABLE)
					committed = commit;
				if ((nmp->nm_flag & NFSMNT_HASWRITEVERF) == 0) {
				    bcopy((caddr_t)tl, (caddr_t)nmp->nm_verf,
					NFSX_V3WRITEVERF);
				    nmp->nm_flag |= NFSMNT_HASWRITEVERF;
				} else if (bcmp((caddr_t)tl,
				    (caddr_t)nmp->nm_verf, NFSX_V3WRITEVERF)) {
				    *must_commit = 1;
				    bcopy((caddr_t)tl, (caddr_t)nmp->nm_verf,
					NFSX_V3WRITEVERF);
				}
			}
		} else
		    nfsm_loadattr(vp, (struct vattr *)0);
		if ((wccflag) && (vp->v_type != VBAD))  /* EINVAL set on VBAD vnode */
		    VTONFS(vp)->n_mtime = VTONFS(vp)->n_vattr.va_mtime.tv_sec;
		m_freem(mrep);
                /*
                 * we seem to have a case where we end up looping on shutdown and taking down nfs servers.
                 * For V3, error cases, there is no way to terminate loop, if the len was 0, meaning,
                 * nmp->nm_wsize was trashed. FreeBSD has this fix in it. Let's try it.
                 */
                if (error)
                    break;
                tsiz -= len;
	}
nfsmout:
        /* does it make sense to even say it was committed if we had an error? EKN */
        /* okay well just don't on bad vnodes then. EINVAL will be returned on bad vnodes */
        if ((vp->v_type != VBAD) && (vp->v_mount->mnt_flag & MNT_ASYNC))
		committed = NFSV3WRITE_FILESYNC;
        *iomode = committed;
	if (error)
		uiop->uio_resid = tsiz;
	return (error);
}

/*
 * nfs mknod rpc
 * For NFS v2 this is a kludge. Use a create rpc but with the IFMT bits of the
 * mode set to specify the file type and the size field for rdev.
 */
static int
nfs_mknodrpc(dvp, vpp, cnp, vap)
	register struct vnode *dvp;
	register struct vnode **vpp;
	register struct componentname *cnp;
	register struct vattr *vap;
{
	register struct nfsv2_sattr *sp;
	register struct nfsv3_sattr *sp3;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	struct vnode *newvp = (struct vnode *)0;
	struct nfsnode *np = (struct nfsnode *)0;
	struct vattr vattr;
	char *cp2;
	caddr_t bpos, dpos;
	int error = 0, wccflag = NFSV3_WCCRATTR, gotvp = 0;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	u_long rdev;
	int v3 = NFS_ISV3(dvp);

	if (vap->va_type == VCHR || vap->va_type == VBLK)
		rdev = txdr_unsigned(vap->va_rdev);
	else if (vap->va_type == VFIFO || vap->va_type == VSOCK)
		rdev = 0xffffffff;
	else {
		VOP_ABORTOP(dvp, cnp);
		vput(dvp);
		return (EOPNOTSUPP);
	}
	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred, cnp->cn_proc))) {
		VOP_ABORTOP(dvp, cnp);
		vput(dvp);
		return (error);
	}
	nfsstats.rpccnt[NFSPROC_MKNOD]++;
	nfsm_reqhead(dvp, NFSPROC_MKNOD, NFSX_FH(v3) + 4 * NFSX_UNSIGNED +
		+ nfsm_rndup(cnp->cn_namelen) + NFSX_SATTR(v3));
	nfsm_fhtom(dvp, v3);
	nfsm_strtom(cnp->cn_nameptr, cnp->cn_namelen, NFS_MAXNAMLEN);
	if (v3) {
		nfsm_build(tl, u_long *, NFSX_UNSIGNED + NFSX_V3SRVSATTR);
		*tl++ = vtonfsv3_type(vap->va_type);
		sp3 = (struct nfsv3_sattr *)tl;
		nfsm_v3sattr(sp3, vap, cnp->cn_cred->cr_uid, vattr.va_gid);
		if (vap->va_type == VCHR || vap->va_type == VBLK) {
			nfsm_build(tl, u_long *, 2 * NFSX_UNSIGNED);
			*tl++ = txdr_unsigned(major(vap->va_rdev));
			*tl = txdr_unsigned(minor(vap->va_rdev));
		}
	} else {
		nfsm_build(sp, struct nfsv2_sattr *, NFSX_V2SATTR);
		sp->sa_mode = vtonfsv2_mode(vap->va_type, vap->va_mode);
		sp->sa_uid = txdr_unsigned(cnp->cn_cred->cr_uid);
		sp->sa_gid = txdr_unsigned(vattr.va_gid);
		sp->sa_size = rdev;
		txdr_nfsv2time(&vap->va_atime, &sp->sa_atime);
		txdr_nfsv2time(&vap->va_mtime, &sp->sa_mtime);
	}
	nfsm_request(dvp, NFSPROC_MKNOD, cnp->cn_proc, cnp->cn_cred);
	if (!error) {
		nfsm_mtofh(dvp, newvp, v3, gotvp);
		if (!gotvp) {
			if (newvp) {
				vput(newvp);
				newvp = (struct vnode *)0;
			}
			error = nfs_lookitup(dvp, cnp->cn_nameptr,
			    cnp->cn_namelen, cnp->cn_cred, cnp->cn_proc, &np);
			if (!error)
				newvp = NFSTOV(np);
		}
	}
	if (v3)
		nfsm_wcc_data(dvp, wccflag);
	nfsm_reqdone;
	if (error) {
		if (newvp)
			vput(newvp);
	} else {
		if (cnp->cn_flags & MAKEENTRY)
			cache_enter(dvp, newvp, cnp);
		*vpp = newvp;
	}
	FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
        if (dvp->v_type != VBAD) { /* EINVAL set on VBAD vnode */
            VTONFS(dvp)->n_flag |= NMODIFIED;
            if (!wccflag)
		VTONFS(dvp)->n_attrstamp = 0;
            }
	vput(dvp);
	return (error);
}

/*
 * nfs mknod vop
 * just call nfs_mknodrpc() to do the work.
 */
/* ARGSUSED */
static int
nfs_mknod(ap)
	struct vop_mknod_args /* {
		struct vnode *a_dvp;
		struct vnode **a_vpp;
		struct componentname *a_cnp;
		struct vattr *a_vap;
	} */ *ap;
{
	struct vnode *newvp;
	int error;

	error = nfs_mknodrpc(ap->a_dvp, &newvp, ap->a_cnp, ap->a_vap);
	if (!error)
		vput(newvp);
	return (error);
}

static u_long create_verf;
/*
 * nfs file create call
 */
static int
nfs_create(ap)
	struct vop_create_args /* {
		struct vnode *a_dvp;
		struct vnode **a_vpp;
		struct componentname *a_cnp;
		struct vattr *a_vap;
	} */ *ap;
{
	register struct vnode *dvp = ap->a_dvp;
	register struct vattr *vap = ap->a_vap;
	register struct componentname *cnp = ap->a_cnp;
	register struct nfsv2_sattr *sp;
	register struct nfsv3_sattr *sp3;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	struct nfsnode *np = (struct nfsnode *)0;
	struct vnode *newvp = (struct vnode *)0;
	caddr_t bpos, dpos, cp2;
	int error = 0, wccflag = NFSV3_WCCRATTR, gotvp = 0, fmode = 0;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	struct vattr vattr;
	int v3 = NFS_ISV3(dvp);

	/*
	 * Oops, not for me..
	 */
	if (vap->va_type == VSOCK)
		return (nfs_mknodrpc(dvp, ap->a_vpp, cnp, vap));

	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred, cnp->cn_proc))) {
		VOP_ABORTOP(dvp, cnp);
		vput(dvp);
		return (error);
	}
	if (vap->va_vaflags & VA_EXCLUSIVE)
		fmode |= O_EXCL;
again:
	nfsstats.rpccnt[NFSPROC_CREATE]++;
	nfsm_reqhead(dvp, NFSPROC_CREATE, NFSX_FH(v3) + 2 * NFSX_UNSIGNED +
		nfsm_rndup(cnp->cn_namelen) + NFSX_SATTR(v3));
	nfsm_fhtom(dvp, v3);
	nfsm_strtom(cnp->cn_nameptr, cnp->cn_namelen, NFS_MAXNAMLEN);
	if (v3) {
		nfsm_build(tl, u_long *, NFSX_UNSIGNED);
		if (fmode & O_EXCL) {
		    *tl = txdr_unsigned(NFSV3CREATE_EXCLUSIVE);
		    nfsm_build(tl, u_long *, NFSX_V3CREATEVERF);
		    if (!TAILQ_EMPTY(&in_ifaddrhead))
			*tl++ = IA_SIN(in_ifaddrhead.tqh_first)->sin_addr.s_addr;
		    else
			*tl++ = create_verf;
		    *tl = ++create_verf;
		} else {
		    *tl = txdr_unsigned(NFSV3CREATE_UNCHECKED);
		    nfsm_build(tl, u_long *, NFSX_V3SRVSATTR);
		    sp3 = (struct nfsv3_sattr *)tl;
		    nfsm_v3sattr(sp3, vap, cnp->cn_cred->cr_uid, vattr.va_gid);
		}
	} else {
		nfsm_build(sp, struct nfsv2_sattr *, NFSX_V2SATTR);
		sp->sa_mode = vtonfsv2_mode(vap->va_type, vap->va_mode);
		sp->sa_uid = txdr_unsigned(cnp->cn_cred->cr_uid);
		sp->sa_gid = txdr_unsigned(vattr.va_gid);
		sp->sa_size = 0;
		txdr_nfsv2time(&vap->va_atime, &sp->sa_atime);
		txdr_nfsv2time(&vap->va_mtime, &sp->sa_mtime);
	}
	nfsm_request(dvp, NFSPROC_CREATE, cnp->cn_proc, cnp->cn_cred);
	if (!error) {
		nfsm_mtofh(dvp, newvp, v3, gotvp);
		if (!gotvp) {
			if (newvp) {
				vput(newvp);
				newvp = (struct vnode *)0;
			}
			error = nfs_lookitup(dvp, cnp->cn_nameptr,
			    cnp->cn_namelen, cnp->cn_cred, cnp->cn_proc, &np);
			if (!error)
				newvp = NFSTOV(np);
		}
	}
	if (v3)
		nfsm_wcc_data(dvp, wccflag);
	nfsm_reqdone;
	if (error) {
		if (v3 && (fmode & O_EXCL) && error == NFSERR_NOTSUPP) {
			fmode &= ~O_EXCL;
			goto again;
		}
		if (newvp)
			vput(newvp);
	} else if (v3 && (fmode & O_EXCL))
		error = nfs_setattrrpc(newvp, vap, cnp->cn_cred, cnp->cn_proc);
	if (!error) {
		if (cnp->cn_flags & MAKEENTRY)
			cache_enter(dvp, newvp, cnp);
		*ap->a_vpp = newvp;
	}
	FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
        if (dvp->v_type != VBAD) { /* EINVAL set on VBAD vnode */
            VTONFS(dvp)->n_flag |= NMODIFIED;
            if (!wccflag)
                    VTONFS(dvp)->n_attrstamp = 0;
        }
	vput(dvp);
	return (error);
}

/*
 * nfs file remove call
 * To try and make nfs semantics closer to ufs semantics, a file that has
 * other processes using the vnode is renamed instead of removed and then
 * removed later on the last close.
 * - If v_usecount > 1
 *	  If a rename is not already in the works
 *	     call nfs_sillyrename() to set it up
 *     else
 *	  do the remove rpc
 */
static int
nfs_remove(ap)
	struct vop_remove_args /* {
		struct vnodeop_desc *a_desc;
		struct vnode * a_dvp;
		struct vnode * a_vp;
		struct componentname * a_cnp;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct vnode *dvp = ap->a_dvp;
	register struct componentname *cnp = ap->a_cnp;
	register struct nfsnode *np = VTONFS(vp);
	int error = 0;
	struct vattr vattr;
	int file_deleted = 0;

#if DIAGNOSTIC
	if ((cnp->cn_flags & HASBUF) == 0)
		panic("nfs_remove: no name");
	if (vp->v_usecount < 1)
		panic("nfs_remove: bad v_usecount");
#endif
	if (vp->v_usecount == 1 || 
		(UBCISVALID(vp)&&(vp->v_usecount==2)) || 
		(np->n_sillyrename &&
	    VOP_GETATTR(vp, &vattr, cnp->cn_cred, cnp->cn_proc) == 0 &&
	    vattr.va_nlink > 1)) {
		/*
		 * Purge the name cache so that the chance of a lookup for
		 * the name succeeding while the remove is in progress is
		 * minimized. Without node locking it can still happen, such
		 * that an I/O op returns ESTALE, but since you get this if
		 * another host removes the file..
		 */
		cache_purge(vp);
		/*
		 * throw away biocache buffers, mainly to avoid
		 * unnecessary delayed writes later.
		 */
		error = nfs_vinvalbuf(vp, 0, cnp->cn_cred, cnp->cn_proc, 1);
		ubc_setsize(vp, (off_t)0);
		/* Do the rpc */
		if (error != EINTR)
			error = nfs_removerpc(dvp, cnp->cn_nameptr,
				cnp->cn_namelen, cnp->cn_cred, cnp->cn_proc);
		/*
		 * Kludge City: If the first reply to the remove rpc is lost..
		 *   the reply to the retransmitted request will be ENOENT
		 *   since the file was in fact removed
		 *   Therefore, we cheat and return success.
		 */
		if (error == ENOENT)
			error = 0;
		file_deleted = 1;
	} else if (!np->n_sillyrename) {
		error = nfs_sillyrename(dvp, vp, cnp);
	}

	FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
	np->n_attrstamp = 0;
	vput(dvp);


	if (vp == dvp)
		vrele(vp);
	else
		vput(vp);

	if (file_deleted && UBCINFOEXISTS(vp)) {
		(void) ubc_uncache(vp); 
		ubc_release(vp);
		/* WARNING vp may not be valid after this */
	}

	return (error);
}

/*
 * nfs file remove rpc called from nfs_inactive
 */
int
nfs_removeit(sp)
	register struct sillyrename *sp;
{

	return (nfs_removerpc(sp->s_dvp, sp->s_name, sp->s_namlen, sp->s_cred,
		(struct proc *)0));
}

/*
 * Nfs remove rpc, called from nfs_remove() and nfs_removeit().
 */
static int
nfs_removerpc(dvp, name, namelen, cred, proc)
	register struct vnode *dvp;
	char *name;
	int namelen;
	struct ucred *cred;
	struct proc *proc;
{
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	caddr_t bpos, dpos, cp2;
	int error = 0, wccflag = NFSV3_WCCRATTR;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	int v3 = NFS_ISV3(dvp);

	nfsstats.rpccnt[NFSPROC_REMOVE]++;
	nfsm_reqhead(dvp, NFSPROC_REMOVE,
		NFSX_FH(v3) + NFSX_UNSIGNED + nfsm_rndup(namelen));
	nfsm_fhtom(dvp, v3);
	nfsm_strtom(name, namelen, NFS_MAXNAMLEN);
	nfsm_request(dvp, NFSPROC_REMOVE, proc, cred);
	if (v3)
		nfsm_wcc_data(dvp, wccflag);
	nfsm_reqdone;
        if (dvp->v_type != VBAD) { /* EINVAL set on VBAD vnode */
            VTONFS(dvp)->n_flag |= NMODIFIED;
            if (!wccflag)
		VTONFS(dvp)->n_attrstamp = 0;
        }
	return (error);
}

/*
 * nfs file rename call
 */
static int
nfs_rename(ap)
	struct vop_rename_args  /* {
		struct vnode *a_fdvp;
		struct vnode *a_fvp;
		struct componentname *a_fcnp;
		struct vnode *a_tdvp;
		struct vnode *a_tvp;
		struct componentname *a_tcnp;
	} */ *ap;
{
	register struct vnode *fvp = ap->a_fvp;
	register struct vnode *tvp = ap->a_tvp;
	register struct vnode *fdvp = ap->a_fdvp;
	register struct vnode *tdvp = ap->a_tdvp;
	register struct componentname *tcnp = ap->a_tcnp;
	register struct componentname *fcnp = ap->a_fcnp;
	int error;

#if DIAGNOSTIC
	if ((tcnp->cn_flags & HASBUF) == 0 ||
	    (fcnp->cn_flags & HASBUF) == 0)
		panic("nfs_rename: no name");
#endif
	/* Check for cross-device rename */
	if ((fvp->v_mount != tdvp->v_mount) ||
	    (tvp && (fvp->v_mount != tvp->v_mount))) {
		error = EXDEV;
		goto out;
	}

	/*
	 * If the tvp exists and is in use, sillyrename it before doing the
	 * rename of the new file over it.
	 * XXX Can't sillyrename a directory.
	 */
	if (tvp && (tvp->v_usecount>(UBCISVALID(tvp) ? 2 : 1)) &&
                !VTONFS(tvp)->n_sillyrename &&
		tvp->v_type != VDIR && !nfs_sillyrename(tdvp, tvp, tcnp)) {
		vput(tvp);
		tvp = NULL;
	}

	error = nfs_renamerpc(fdvp, fcnp->cn_nameptr, fcnp->cn_namelen,
		tdvp, tcnp->cn_nameptr, tcnp->cn_namelen, tcnp->cn_cred,
		tcnp->cn_proc);

	if (fvp->v_type == VDIR) {
		if (tvp != NULL && tvp->v_type == VDIR)
			cache_purge(tdvp);
		cache_purge(fdvp);
	}
out:
	if (tdvp == tvp)
		vrele(tdvp);
	else
		vput(tdvp);
	if (tvp)
		vput(tvp);
	vrele(fdvp);
	vrele(fvp);
	/*
	 * Kludge: Map ENOENT => 0 assuming that it is a reply to a retry.
	 */
	if (error == ENOENT)
		error = 0;
	return (error);
}

/*
 * nfs file rename rpc called from nfs_remove() above
 */
static int
nfs_renameit(sdvp, scnp, sp)
	struct vnode *sdvp;
	struct componentname *scnp;
	register struct sillyrename *sp;
{
	return (nfs_renamerpc(sdvp, scnp->cn_nameptr, scnp->cn_namelen,
		sdvp, sp->s_name, sp->s_namlen, scnp->cn_cred, scnp->cn_proc));
}

/*
 * Do an nfs rename rpc. Called from nfs_rename() and nfs_renameit().
 */
static int
nfs_renamerpc(fdvp, fnameptr, fnamelen, tdvp, tnameptr, tnamelen, cred, proc)
	register struct vnode *fdvp;
	char *fnameptr;
	int fnamelen;
	register struct vnode *tdvp;
	char *tnameptr;
	int tnamelen;
	struct ucred *cred;
	struct proc *proc;
{
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	caddr_t bpos, dpos, cp2;
	int error = 0, fwccflag = NFSV3_WCCRATTR, twccflag = NFSV3_WCCRATTR;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	int v3 = NFS_ISV3(fdvp);

	nfsstats.rpccnt[NFSPROC_RENAME]++;
	nfsm_reqhead(fdvp, NFSPROC_RENAME,
		(NFSX_FH(v3) + NFSX_UNSIGNED)*2 + nfsm_rndup(fnamelen) +
		nfsm_rndup(tnamelen));
	nfsm_fhtom(fdvp, v3);
	nfsm_strtom(fnameptr, fnamelen, NFS_MAXNAMLEN);
	nfsm_fhtom(tdvp, v3);
	nfsm_strtom(tnameptr, tnamelen, NFS_MAXNAMLEN);
	nfsm_request(fdvp, NFSPROC_RENAME, proc, cred);
	if (v3) {
		nfsm_wcc_data(fdvp, fwccflag);
		nfsm_wcc_data(tdvp, twccflag);
	}
	nfsm_reqdone;
        if (fdvp->v_type != VBAD) { /* EINVAL set on VBAD vnode */
            VTONFS(fdvp)->n_flag |= NMODIFIED;
            if (!fwccflag)
		VTONFS(fdvp)->n_attrstamp = 0;
        }
        if (tdvp->v_type != VBAD) { /* EINVAL set on VBAD vnode */
            VTONFS(tdvp)->n_flag |= NMODIFIED;
            if (!twccflag)
                    VTONFS(tdvp)->n_attrstamp = 0;
        }
	return (error);
}

/*
 * nfs hard link create call
 */
static int
nfs_link(ap)
	struct vop_link_args /* {
		struct vnode *a_vp;
		struct vnode *a_tdvp;
		struct componentname *a_cnp;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct vnode *tdvp = ap->a_tdvp;
	register struct componentname *cnp = ap->a_cnp;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	caddr_t bpos, dpos, cp2;
	int error = 0, wccflag = NFSV3_WCCRATTR, attrflag = 0;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	int v3 = NFS_ISV3(vp);

	if (vp->v_mount != tdvp->v_mount) {
		VOP_ABORTOP(vp, cnp);
		if (tdvp == vp)
			vrele(tdvp);
		else
			vput(tdvp);
		return (EXDEV);
	}

	/*
	 * Push all writes to the server, so that the attribute cache
	 * doesn't get "out of sync" with the server.
	 * XXX There should be a better way!
	 */
	VOP_FSYNC(vp, cnp->cn_cred, MNT_WAIT, cnp->cn_proc);

	nfsstats.rpccnt[NFSPROC_LINK]++;
	nfsm_reqhead(vp, NFSPROC_LINK,
		NFSX_FH(v3)*2 + NFSX_UNSIGNED + nfsm_rndup(cnp->cn_namelen));
	nfsm_fhtom(vp, v3);
	nfsm_fhtom(tdvp, v3);
	nfsm_strtom(cnp->cn_nameptr, cnp->cn_namelen, NFS_MAXNAMLEN);
	nfsm_request(vp, NFSPROC_LINK, cnp->cn_proc, cnp->cn_cred);
	if (v3) {
		nfsm_postop_attr(vp, attrflag);
		nfsm_wcc_data(tdvp, wccflag);
	}
	nfsm_reqdone;
	FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);

	VTONFS(tdvp)->n_flag |= NMODIFIED;
	if ((!attrflag) && (vp->v_type != VBAD))  /* EINVAL set on VBAD vnode */
		VTONFS(vp)->n_attrstamp = 0;
	if ((!wccflag) && (tdvp->v_type != VBAD))  /* EINVAL set on VBAD vnode */
		VTONFS(tdvp)->n_attrstamp = 0;
	vput(tdvp);
	/*
	 * Kludge: Map EEXIST => 0 assuming that it is a reply to a retry.
	 */
	if (error == EEXIST)
		error = 0;
	return (error);
}

/*
 * nfs symbolic link create call
 */
static int
nfs_symlink(ap)
	struct vop_symlink_args /* {
		struct vnode *a_dvp;
		struct vnode **a_vpp;
		struct componentname *a_cnp;
		struct vattr *a_vap;
		char *a_target;
	} */ *ap;
{
	register struct vnode *dvp = ap->a_dvp;
	register struct vattr *vap = ap->a_vap;
	register struct componentname *cnp = ap->a_cnp;
	register struct nfsv2_sattr *sp;
	register struct nfsv3_sattr *sp3;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	caddr_t bpos, dpos, cp2;
	int slen, error = 0, wccflag = NFSV3_WCCRATTR, gotvp;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	struct vnode *newvp = (struct vnode *)0;
	int v3 = NFS_ISV3(dvp);

	nfsstats.rpccnt[NFSPROC_SYMLINK]++;
	slen = strlen(ap->a_target);
	nfsm_reqhead(dvp, NFSPROC_SYMLINK, NFSX_FH(v3) + 2*NFSX_UNSIGNED +
	    nfsm_rndup(cnp->cn_namelen) + nfsm_rndup(slen) + NFSX_SATTR(v3));
	nfsm_fhtom(dvp, v3);
	nfsm_strtom(cnp->cn_nameptr, cnp->cn_namelen, NFS_MAXNAMLEN);
	if (v3) {
		nfsm_build(sp3, struct nfsv3_sattr *, NFSX_V3SRVSATTR);
		nfsm_v3sattr(sp3, vap, cnp->cn_cred->cr_uid,
			cnp->cn_cred->cr_gid);
	}
	nfsm_strtom(ap->a_target, slen, NFS_MAXPATHLEN);
	if (!v3) {
		nfsm_build(sp, struct nfsv2_sattr *, NFSX_V2SATTR);
		sp->sa_mode = vtonfsv2_mode(VLNK, vap->va_mode);
		sp->sa_uid = txdr_unsigned(cnp->cn_cred->cr_uid);
		sp->sa_gid = txdr_unsigned(cnp->cn_cred->cr_gid);
		sp->sa_size = -1;
		txdr_nfsv2time(&vap->va_atime, &sp->sa_atime);
		txdr_nfsv2time(&vap->va_mtime, &sp->sa_mtime);
	}
	nfsm_request(dvp, NFSPROC_SYMLINK, cnp->cn_proc, cnp->cn_cred);
	if (v3) {
		if (!error)
			nfsm_mtofh(dvp, newvp, v3, gotvp);
		nfsm_wcc_data(dvp, wccflag);
	}
	nfsm_reqdone;
	if (newvp)
		vput(newvp);
	FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
        if (dvp->v_type != VBAD) { /* EINVAL set on VBAD vnode */
            VTONFS(dvp)->n_flag |= NMODIFIED;
            if (!wccflag)
		VTONFS(dvp)->n_attrstamp = 0;
        }
	vput(dvp);
	/*
	 * Kludge: Map EEXIST => 0 assuming that it is a reply to a retry.
	 */
	if (error == EEXIST)
		error = 0;
	return (error);
}

/*
 * nfs make dir call
 */
static int
nfs_mkdir(ap)
	struct vop_mkdir_args /* {
		struct vnode *a_dvp;
		struct vnode **a_vpp;
		struct componentname *a_cnp;
		struct vattr *a_vap;
	} */ *ap;
{
	register struct vnode *dvp = ap->a_dvp;
	register struct vattr *vap = ap->a_vap;
	register struct componentname *cnp = ap->a_cnp;
	register struct nfsv2_sattr *sp;
	register struct nfsv3_sattr *sp3;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	register int len;
	struct nfsnode *np = (struct nfsnode *)0;
	struct vnode *newvp = (struct vnode *)0;
	caddr_t bpos, dpos, cp2;
	int error = 0, wccflag = NFSV3_WCCRATTR;
	int gotvp = 0;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	struct vattr vattr;
	int v3 = NFS_ISV3(dvp);

	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred, cnp->cn_proc))) {
		VOP_ABORTOP(dvp, cnp);
		vput(dvp);
		return (error);
	}
	len = cnp->cn_namelen;
	nfsstats.rpccnt[NFSPROC_MKDIR]++;
	nfsm_reqhead(dvp, NFSPROC_MKDIR,
	  NFSX_FH(v3) + NFSX_UNSIGNED + nfsm_rndup(len) + NFSX_SATTR(v3));
	nfsm_fhtom(dvp, v3);
	nfsm_strtom(cnp->cn_nameptr, len, NFS_MAXNAMLEN);
	if (v3) {
		nfsm_build(sp3, struct nfsv3_sattr *, NFSX_V3SRVSATTR);
		nfsm_v3sattr(sp3, vap, cnp->cn_cred->cr_uid, vattr.va_gid);
	} else {
		nfsm_build(sp, struct nfsv2_sattr *, NFSX_V2SATTR);
		sp->sa_mode = vtonfsv2_mode(VDIR, vap->va_mode);
		sp->sa_uid = txdr_unsigned(cnp->cn_cred->cr_uid);
		sp->sa_gid = txdr_unsigned(vattr.va_gid);
		sp->sa_size = -1;
		txdr_nfsv2time(&vap->va_atime, &sp->sa_atime);
		txdr_nfsv2time(&vap->va_mtime, &sp->sa_mtime);
	}
	nfsm_request(dvp, NFSPROC_MKDIR, cnp->cn_proc, cnp->cn_cred);
	if (!error)
		nfsm_mtofh(dvp, newvp, v3, gotvp);
	if (v3)
		nfsm_wcc_data(dvp, wccflag);
	nfsm_reqdone;
        if (dvp->v_type != VBAD) { /* EINVAL set on this case */
            VTONFS(dvp)->n_flag |= NMODIFIED;
            if (!wccflag)
		VTONFS(dvp)->n_attrstamp = 0;
        }
	/*
	 * Kludge: Map EEXIST => 0 assuming that you have a reply to a retry
	 * if we can succeed in looking up the directory.
	 */
	if (error == EEXIST || (!error && !gotvp)) {
		if (newvp) {
			vrele(newvp);
			newvp = (struct vnode *)0;
		}
		error = nfs_lookitup(dvp, cnp->cn_nameptr, len, cnp->cn_cred,
			cnp->cn_proc, &np);
		if (!error) {
			newvp = NFSTOV(np);
			if (newvp->v_type != VDIR)
				error = EEXIST;
		}
	}
	if (error) {
		if (newvp)
			vrele(newvp);
	} else
		*ap->a_vpp = newvp;
	FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
	vput(dvp);
	return (error);
}

/*
 * nfs remove directory call
 */
static int
nfs_rmdir(ap)
	struct vop_rmdir_args /* {
		struct vnode *a_dvp;
		struct vnode *a_vp;
		struct componentname *a_cnp;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct vnode *dvp = ap->a_dvp;
	register struct componentname *cnp = ap->a_cnp;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	caddr_t bpos, dpos, cp2;
	int error = 0, wccflag = NFSV3_WCCRATTR;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	int v3 = NFS_ISV3(dvp);

	nfsstats.rpccnt[NFSPROC_RMDIR]++;
	nfsm_reqhead(dvp, NFSPROC_RMDIR,
		NFSX_FH(v3) + NFSX_UNSIGNED + nfsm_rndup(cnp->cn_namelen));
	nfsm_fhtom(dvp, v3);
	nfsm_strtom(cnp->cn_nameptr, cnp->cn_namelen, NFS_MAXNAMLEN);
	nfsm_request(dvp, NFSPROC_RMDIR, cnp->cn_proc, cnp->cn_cred);
	if (v3)
		nfsm_wcc_data(dvp, wccflag);
	nfsm_reqdone;
	FREE_ZONE(cnp->cn_pnbuf, cnp->cn_pnlen, M_NAMEI);
        if (dvp->v_type != VBAD) { /* EINVAL set on this case */
            VTONFS(dvp)->n_flag |= NMODIFIED;
            if (!wccflag)
		VTONFS(dvp)->n_attrstamp = 0;
        }
	cache_purge(dvp);
	cache_purge(vp);
	vput(vp);
	vput(dvp);
	/*
	 * Kludge: Map ENOENT => 0 assuming that you have a reply to a retry.
	 */
	if (error == ENOENT)
		error = 0;
	return (error);
}

/*
 * nfs readdir call
 */
static int
nfs_readdir(ap)
	struct vop_readdir_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		struct ucred *a_cred;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct nfsnode *np = VTONFS(vp);
	register struct uio *uio = ap->a_uio;
	int tresid, error;
	struct vattr vattr;

	if (vp->v_type != VDIR)
		return (EPERM);
	/*
	 * First, check for hit on the EOF offset cache
	 */
	if (np->n_direofoffset > 0 && uio->uio_offset >= np->n_direofoffset &&
	    (np->n_flag & NMODIFIED) == 0) {
		if (VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NQNFS) {
			if (NQNFS_CKCACHABLE(vp, ND_READ)) {
				nfsstats.direofcache_hits++;
				return (0);
			}
		} else if (VOP_GETATTR(vp, &vattr, ap->a_cred, uio->uio_procp) == 0 &&
			np->n_mtime == vattr.va_mtime.tv_sec) {
			nfsstats.direofcache_hits++;
			return (0);
		}
	}

	/*
	 * Call nfs_bioread() to do the real work.
	 */
	tresid = uio->uio_resid;
	error = nfs_bioread(vp, uio, 0, ap->a_cred, 0);

	if (!error && uio->uio_resid == tresid)
		nfsstats.direofcache_misses++;
	return (error);
}

/*
 * Readdir rpc call.
 * Called from below the buffer cache by nfs_doio().
 */
int
nfs_readdirrpc(vp, uiop, cred)
	struct vnode *vp;
	register struct uio *uiop;
	struct ucred *cred;

{
	register int len, left;
	register struct dirent *dp;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	register nfsuint64 *cookiep;
	caddr_t bpos, dpos, cp2;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	nfsuint64 cookie;
	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
	struct nfsnode *dnp = VTONFS(vp);
	u_quad_t fileno;
	int error = 0, tlen, more_dirs = 1, blksiz = 0, bigenough = 1;
	int attrflag;
	int v3 = NFS_ISV3(vp);

#ifndef nolint
	dp = (struct dirent *)0;
#endif
#if DIAGNOSTIC
	if (uiop->uio_iovcnt != 1 || (uiop->uio_offset & (NFS_DIRBLKSIZ - 1)) ||
		(uiop->uio_resid & (NFS_DIRBLKSIZ - 1)))
		panic("nfs_readdirrpc: bad uio");
#endif

	/*
	 * If there is no cookie, assume directory was stale.
	 */
	cookiep = nfs_getcookie(dnp, uiop->uio_offset, 0);
	if (cookiep)
		cookie = *cookiep;
	else
		return (NFSERR_BAD_COOKIE);
	/*
	 * Loop around doing readdir rpc's of size nm_readdirsize
	 * truncated to a multiple of DIRBLKSIZ.
	 * The stopping criteria is EOF or buffer full.
	 */
	while (more_dirs && bigenough) {
		nfsstats.rpccnt[NFSPROC_READDIR]++;
		nfsm_reqhead(vp, NFSPROC_READDIR, NFSX_FH(v3) +
			NFSX_READDIR(v3));
		nfsm_fhtom(vp, v3);
		if (v3) {
			nfsm_build(tl, u_long *, 5 * NFSX_UNSIGNED);
			*tl++ = cookie.nfsuquad[0];
			*tl++ = cookie.nfsuquad[1];
			*tl++ = dnp->n_cookieverf.nfsuquad[0];
			*tl++ = dnp->n_cookieverf.nfsuquad[1];
		} else {
			nfsm_build(tl, u_long *, 2 * NFSX_UNSIGNED);
			*tl++ = cookie.nfsuquad[0];
		}
		*tl = txdr_unsigned(nmp->nm_readdirsize);
		nfsm_request(vp, NFSPROC_READDIR, uiop->uio_procp, cred);
		if (v3) {
			nfsm_postop_attr(vp, attrflag);
			if (!error) {
				nfsm_dissect(tl, u_long *, 2 * NFSX_UNSIGNED);
				dnp->n_cookieverf.nfsuquad[0] = *tl++;
				dnp->n_cookieverf.nfsuquad[1] = *tl;
			} else {
				m_freem(mrep);
				goto nfsmout;
			}
		}
		nfsm_dissect(tl, u_long *, NFSX_UNSIGNED);
		more_dirs = fxdr_unsigned(int, *tl);
	
		/* loop thru the dir entries, doctoring them to 4bsd form */
		while (more_dirs && bigenough) {
			if (v3) {
				nfsm_dissect(tl, u_long *, 3 * NFSX_UNSIGNED);
				fxdr_hyper(tl, &fileno);
				len = fxdr_unsigned(int, *(tl + 2));
			} else {
				nfsm_dissect(tl, u_long *, 2 * NFSX_UNSIGNED);
				fileno = fxdr_unsigned(u_quad_t, *tl++);
				len = fxdr_unsigned(int, *tl);
			}
			if (len <= 0 || len > NFS_MAXNAMLEN) {
				error = EBADRPC;
				m_freem(mrep);
				goto nfsmout;
			}
			tlen = nfsm_rndup(len);
			if (tlen == len)
				tlen += 4;	/* To ensure null termination */
			left = DIRBLKSIZ - blksiz;
			if ((tlen + DIRHDSIZ) > left) {
				dp->d_reclen += left;
				uiop->uio_iov->iov_base += left;
				uiop->uio_iov->iov_len -= left;
				uiop->uio_offset += left;
				uiop->uio_resid -= left;
				blksiz = 0;
			}
			if ((tlen + DIRHDSIZ) > uiop->uio_resid)
				bigenough = 0;
			if (bigenough) {
				dp = (struct dirent *)uiop->uio_iov->iov_base;
				dp->d_fileno = (int)fileno;
				dp->d_namlen = len;
				dp->d_reclen = tlen + DIRHDSIZ;
				dp->d_type = DT_UNKNOWN;
				blksiz += dp->d_reclen;
				if (blksiz == DIRBLKSIZ)
					blksiz = 0;
				uiop->uio_offset += DIRHDSIZ;
				uiop->uio_resid -= DIRHDSIZ;
				uiop->uio_iov->iov_base += DIRHDSIZ;
				uiop->uio_iov->iov_len -= DIRHDSIZ;
				nfsm_mtouio(uiop, len);
				cp = uiop->uio_iov->iov_base;
				tlen -= len;
				*cp = '\0';	/* null terminate */
				uiop->uio_iov->iov_base += tlen;
				uiop->uio_iov->iov_len -= tlen;
				uiop->uio_offset += tlen;
				uiop->uio_resid -= tlen;
			} else
				nfsm_adv(nfsm_rndup(len));
			if (v3) {
				nfsm_dissect(tl, u_long *, 3 * NFSX_UNSIGNED);
			} else {
				nfsm_dissect(tl, u_long *, 2 * NFSX_UNSIGNED);
			}
			if (bigenough) {
				cookie.nfsuquad[0] = *tl++;
				if (v3)
					cookie.nfsuquad[1] = *tl++;
			} else if (v3)
				tl += 2;
			else
				tl++;
			more_dirs = fxdr_unsigned(int, *tl);
		}
		/*
		 * If at end of rpc data, get the eof boolean
		 */
		if (!more_dirs) {
			nfsm_dissect(tl, u_long *, NFSX_UNSIGNED);
			more_dirs = (fxdr_unsigned(int, *tl) == 0);
		}
		m_freem(mrep);
	}
	/*
	 * Fill last record, iff any, out to a multiple of DIRBLKSIZ
	 * by increasing d_reclen for the last record.
	 */
	if (blksiz > 0) {
		left = DIRBLKSIZ - blksiz;
		dp->d_reclen += left;
		uiop->uio_iov->iov_base += left;
		uiop->uio_iov->iov_len -= left;
		uiop->uio_offset += left;
		uiop->uio_resid -= left;
	}

	/*
	 * We are now either at the end of the directory or have filled the
	 * block.
	 */
	if (bigenough)
		dnp->n_direofoffset = uiop->uio_offset;
	else {
		if (uiop->uio_resid > 0)
			printf("EEK! readdirrpc resid > 0\n");
		cookiep = nfs_getcookie(dnp, uiop->uio_offset, 1);
		*cookiep = cookie;
	}
nfsmout:
	return (error);
}

/*
 * NFS V3 readdir plus RPC. Used in place of nfs_readdirrpc().
 */
int
nfs_readdirplusrpc(vp, uiop, cred)
	struct vnode *vp;
	register struct uio *uiop;
	struct ucred *cred;
{
	register int len, left;
	register struct dirent *dp;
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	register struct vnode *newvp;
	register nfsuint64 *cookiep;
	caddr_t bpos, dpos, cp2, dpossav1, dpossav2;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2, *mdsav1, *mdsav2;
	struct nameidata nami, *ndp = &nami;
	struct componentname *cnp = &ndp->ni_cnd;
	nfsuint64 cookie;
	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
	struct nfsnode *dnp = VTONFS(vp), *np;
	nfsfh_t *fhp;
	u_quad_t fileno;
	int error = 0, tlen, more_dirs = 1, blksiz = 0, doit, bigenough = 1, i;
	int attrflag, fhsize;

#ifndef nolint
	dp = (struct dirent *)0;
#endif
#if DIAGNOSTIC
	if (uiop->uio_iovcnt != 1 || (uiop->uio_offset & (DIRBLKSIZ - 1)) ||
		(uiop->uio_resid & (DIRBLKSIZ - 1)))
		panic("nfs_readdirplusrpc: bad uio");
#endif
	ndp->ni_dvp = vp;
	newvp = NULLVP;

	/*
	 * If there is no cookie, assume directory was stale.
	 */
	cookiep = nfs_getcookie(dnp, uiop->uio_offset, 0);
	if (cookiep)
		cookie = *cookiep;
	else
		return (NFSERR_BAD_COOKIE);
	/*
	 * Loop around doing readdir rpc's of size nm_readdirsize
	 * truncated to a multiple of DIRBLKSIZ.
	 * The stopping criteria is EOF or buffer full.
	 */
	while (more_dirs && bigenough) {
		nfsstats.rpccnt[NFSPROC_READDIRPLUS]++;
		nfsm_reqhead(vp, NFSPROC_READDIRPLUS,
			NFSX_FH(1) + 6 * NFSX_UNSIGNED);
		nfsm_fhtom(vp, 1);
 		nfsm_build(tl, u_long *, 6 * NFSX_UNSIGNED);
		*tl++ = cookie.nfsuquad[0];
		*tl++ = cookie.nfsuquad[1];
		*tl++ = dnp->n_cookieverf.nfsuquad[0];
		*tl++ = dnp->n_cookieverf.nfsuquad[1];
		*tl++ = txdr_unsigned(nmp->nm_readdirsize);
		*tl = txdr_unsigned(nmp->nm_rsize);
		nfsm_request(vp, NFSPROC_READDIRPLUS, uiop->uio_procp, cred);
		nfsm_postop_attr(vp, attrflag);
		if (error) {
			m_freem(mrep);
			goto nfsmout;
		}
		nfsm_dissect(tl, u_long *, 3 * NFSX_UNSIGNED);
		dnp->n_cookieverf.nfsuquad[0] = *tl++;
		dnp->n_cookieverf.nfsuquad[1] = *tl++;
		more_dirs = fxdr_unsigned(int, *tl);

		/* loop thru the dir entries, doctoring them to 4bsd form */
		while (more_dirs && bigenough) {
			nfsm_dissect(tl, u_long *, 3 * NFSX_UNSIGNED);
			fxdr_hyper(tl, &fileno);
			len = fxdr_unsigned(int, *(tl + 2));
			if (len <= 0 || len > NFS_MAXNAMLEN) {
				error = EBADRPC;
				m_freem(mrep);
				goto nfsmout;
			}
			tlen = nfsm_rndup(len);
			if (tlen == len)
				tlen += 4;	/* To ensure null termination*/
			left = DIRBLKSIZ - blksiz;
			if ((tlen + DIRHDSIZ) > left) {
				dp->d_reclen += left;
				uiop->uio_iov->iov_base += left;
				uiop->uio_iov->iov_len -= left;
				uiop->uio_offset += left;
				uiop->uio_resid -= left;
				blksiz = 0;
			}
			if ((tlen + DIRHDSIZ) > uiop->uio_resid)
				bigenough = 0;
			if (bigenough) {
				dp = (struct dirent *)uiop->uio_iov->iov_base;
				dp->d_fileno = (int)fileno;
				dp->d_namlen = len;
				dp->d_reclen = tlen + DIRHDSIZ;
				dp->d_type = DT_UNKNOWN;
				blksiz += dp->d_reclen;
				if (blksiz == DIRBLKSIZ)
					blksiz = 0;
				uiop->uio_offset += DIRHDSIZ;
				uiop->uio_resid -= DIRHDSIZ;
				uiop->uio_iov->iov_base += DIRHDSIZ;
				uiop->uio_iov->iov_len -= DIRHDSIZ;
				cnp->cn_nameptr = uiop->uio_iov->iov_base;
				cnp->cn_namelen = len;
				nfsm_mtouio(uiop, len);
				cp = uiop->uio_iov->iov_base;
				tlen -= len;
				*cp = '\0';
				uiop->uio_iov->iov_base += tlen;
				uiop->uio_iov->iov_len -= tlen;
				uiop->uio_offset += tlen;
				uiop->uio_resid -= tlen;
			} else
				nfsm_adv(nfsm_rndup(len));
			nfsm_dissect(tl, u_long *, 3 * NFSX_UNSIGNED);
			if (bigenough) {
				cookie.nfsuquad[0] = *tl++;
				cookie.nfsuquad[1] = *tl++;
			} else
				tl += 2;

			/*
			 * Since the attributes are before the file handle
			 * (sigh), we must skip over the attributes and then
			 * come back and get them.
			 */
			attrflag = fxdr_unsigned(int, *tl);
			if (attrflag) {
			    dpossav1 = dpos;
			    mdsav1 = md;
			    nfsm_adv(NFSX_V3FATTR);
			    nfsm_dissect(tl, u_long *, NFSX_UNSIGNED);
			    doit = fxdr_unsigned(int, *tl);
			    if (doit) {
				nfsm_getfh(fhp, fhsize, 1);
				if (NFS_CMPFH(dnp, fhp, fhsize)) {
				    VREF(vp);
				    newvp = vp;
				    np = dnp;
				} else {
				    if ((error = nfs_nget(vp->v_mount, fhp,
					fhsize, &np)))
					doit = 0;
				    else
					newvp = NFSTOV(np);
				}
			    }
			    if (doit) {
				dpossav2 = dpos;
				dpos = dpossav1;
				mdsav2 = md;
				md = mdsav1;
				nfsm_loadattr(newvp, (struct vattr *)0);
				dpos = dpossav2;
				md = mdsav2;
				dp->d_type =
				    IFTODT(VTTOIF(np->n_vattr.va_type));
				ndp->ni_vp = newvp;
				cnp->cn_hash = 0;
				for (cp = cnp->cn_nameptr, i = 1; i <= len;
				    i++, cp++)
				    cnp->cn_hash += (unsigned char)*cp * i;
				if (cnp->cn_namelen <= NCHNAMLEN)
				    cache_enter(ndp->ni_dvp, ndp->ni_vp, cnp);
			    }
			} else {
			    /* Just skip over the file handle */
			    nfsm_dissect(tl, u_long *, NFSX_UNSIGNED);
			    i = fxdr_unsigned(int, *tl);
			    nfsm_adv(nfsm_rndup(i));
			}
			if (newvp != NULLVP) {
			    vrele(newvp);
			    newvp = NULLVP;
			}
			nfsm_dissect(tl, u_long *, NFSX_UNSIGNED);
			more_dirs = fxdr_unsigned(int, *tl);
		}
		/*
		 * If at end of rpc data, get the eof boolean
		 */
		if (!more_dirs) {
			nfsm_dissect(tl, u_long *, NFSX_UNSIGNED);
			more_dirs = (fxdr_unsigned(int, *tl) == 0);
		}
		m_freem(mrep);
	}
	/*
	 * Fill last record, iff any, out to a multiple of NFS_DIRBLKSIZ
	 * by increasing d_reclen for the last record.
	 */
	if (blksiz > 0) {
		left = DIRBLKSIZ - blksiz;
		dp->d_reclen += left;
		uiop->uio_iov->iov_base += left;
		uiop->uio_iov->iov_len -= left;
		uiop->uio_offset += left;
		uiop->uio_resid -= left;
	}

	/*
	 * We are now either at the end of the directory or have filled the
	 * block.
	 */
	if (bigenough)
		dnp->n_direofoffset = uiop->uio_offset;
	else {
		if (uiop->uio_resid > 0)
			printf("EEK! readdirplusrpc resid > 0\n");
		cookiep = nfs_getcookie(dnp, uiop->uio_offset, 1);
		*cookiep = cookie;
	}
nfsmout:
	if (newvp != NULLVP) {
	        if (newvp == vp)
			vrele(newvp);
		else
			vput(newvp);
		newvp = NULLVP;
	}
	return (error);
}

/*
 * Silly rename. To make the NFS filesystem that is stateless look a little
 * more like the "ufs" a remove of an active vnode is translated to a rename
 * to a funny looking filename that is removed by nfs_inactive on the
 * nfsnode. There is the potential for another process on a different client
 * to create the same funny name between the nfs_lookitup() fails and the
 * nfs_rename() completes, but...
 */
static int
nfs_sillyrename(dvp, vp, cnp)
	struct vnode *dvp, *vp;
	struct componentname *cnp;
{
	register struct sillyrename *sp;
	struct nfsnode *np;
	int error;
	short pid;
	struct ucred *cred;

	cache_purge(dvp);
	np = VTONFS(vp);
#if DIAGNOSTIC
	if (vp->v_type == VDIR)
		panic("nfs_sillyrename: dir");
#endif
	MALLOC_ZONE(sp, struct sillyrename *,
			sizeof (struct sillyrename), M_NFSREQ, M_WAITOK);
	sp->s_cred = crdup(cnp->cn_cred);
	sp->s_dvp = dvp;
	VREF(dvp);

	/* Fudge together a funny name */
	pid = cnp->cn_proc->p_pid;
	sp->s_namlen = sprintf(sp->s_name, ".nfsA%04x4.4", pid);

	/* Try lookitups until we get one that isn't there */
	while (nfs_lookitup(dvp, sp->s_name, sp->s_namlen, sp->s_cred,
		cnp->cn_proc, (struct nfsnode **)0) == 0) {
		sp->s_name[4]++;
		if (sp->s_name[4] > 'z') {
			error = EINVAL;
			goto bad;
		}
	}
	if ((error = nfs_renameit(dvp, cnp, sp)))
		goto bad;
	error = nfs_lookitup(dvp, sp->s_name, sp->s_namlen, sp->s_cred,
		cnp->cn_proc, &np);
#if DIAGNOSTIC
	kprintf("sillyrename: %s, vp=%x, np=%x, dvp=%x\n",
		&sp->s_name[0], (unsigned)vp, (unsigned)np, (unsigned)dvp);
#endif
	np->n_sillyrename = sp;
	return (0);
bad:
	vrele(sp->s_dvp);
	cred = sp->s_cred;
	sp->s_cred = NOCRED;
	crfree(cred);
	_FREE_ZONE((caddr_t)sp, sizeof (struct sillyrename), M_NFSREQ);
	return (error);
}

/*
 * Look up a file name and optionally either update the file handle or
 * allocate an nfsnode, depending on the value of npp.
 * npp == NULL	--> just do the lookup
 * *npp == NULL --> allocate a new nfsnode and make sure attributes are
 *			handled too
 * *npp != NULL --> update the file handle in the vnode
 */
static int
nfs_lookitup(dvp, name, len, cred, procp, npp)
	register struct vnode *dvp;
	char *name;
	int len;
	struct ucred *cred;
	struct proc *procp;
	struct nfsnode **npp;
{
	register u_long *tl;
	register caddr_t cp;
	register long t1, t2;
	struct vnode *newvp = (struct vnode *)0;
	struct nfsnode *np, *dnp = VTONFS(dvp);
	caddr_t bpos, dpos, cp2;
	int error = 0, fhlen, attrflag;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	nfsfh_t *nfhp;
	int v3 = NFS_ISV3(dvp);

	nfsstats.rpccnt[NFSPROC_LOOKUP]++;
	nfsm_reqhead(dvp, NFSPROC_LOOKUP,
		NFSX_FH(v3) + NFSX_UNSIGNED + nfsm_rndup(len));
	nfsm_fhtom(dvp, v3);
	nfsm_strtom(name, len, NFS_MAXNAMLEN);
	nfsm_request(dvp, NFSPROC_LOOKUP, procp, cred);
	if (npp && !error) {
		nfsm_getfh(nfhp, fhlen, v3);
		if (*npp) {
		    np = *npp;
		    if (np->n_fhsize > NFS_SMALLFH && fhlen <= NFS_SMALLFH) {
			_FREE_ZONE((caddr_t)np->n_fhp,
					np->n_fhsize, M_NFSBIGFH);
			np->n_fhp = &np->n_fh;
		    } else if (np->n_fhsize <= NFS_SMALLFH && fhlen>NFS_SMALLFH)
			MALLOC_ZONE(np->n_fhp, nfsfh_t *,
						fhlen, M_NFSBIGFH, M_WAITOK);
		    bcopy((caddr_t)nfhp, (caddr_t)np->n_fhp, fhlen);
		    np->n_fhsize = fhlen;
		    newvp = NFSTOV(np);
		} else if (NFS_CMPFH(dnp, nfhp, fhlen)) {
		    VREF(dvp);
		    newvp = dvp;
		} else {
		    error = nfs_nget(dvp->v_mount, nfhp, fhlen, &np);
		    if (error) {
			m_freem(mrep);
			return (error);
		    }
		    newvp = NFSTOV(np);
		}
		if (v3) {
			nfsm_postop_attr(newvp, attrflag);
			if (!attrflag && *npp == NULL) {
				m_freem(mrep);
				if (newvp == dvp)
					vrele(newvp);
				else
					vput(newvp);
				return (ENOENT);
			}
		} else
			nfsm_loadattr(newvp, (struct vattr *)0);
	}
	nfsm_reqdone;
	if (npp && *npp == NULL) {
		if (error) {
			if (newvp)
				if (newvp == dvp)
					vrele(newvp);
				else
					vput(newvp);
		} else
			*npp = np;
	}
	return (error);
}

/*
 * Nfs Version 3 commit rpc
 */
static int
nfs_commit(vp, offset, cnt, cred, procp)
	register struct vnode *vp;
	u_quad_t offset;
	int cnt;
	struct ucred *cred;
	struct proc *procp;
{
	register caddr_t cp;
	register u_long *tl;
	register int t1, t2;
	register struct nfsmount *nmp = VFSTONFS(vp->v_mount);
	caddr_t bpos, dpos, cp2;
	int error = 0, wccflag = NFSV3_WCCRATTR;
	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
	
	if ((nmp->nm_flag & NFSMNT_HASWRITEVERF) == 0)
		return (0);
	nfsstats.rpccnt[NFSPROC_COMMIT]++;
	nfsm_reqhead(vp, NFSPROC_COMMIT, NFSX_FH(1));
	nfsm_fhtom(vp, 1);
	nfsm_build(tl, u_long *, 3 * NFSX_UNSIGNED);
	txdr_hyper(&offset, tl);
	tl += 2;
	*tl = txdr_unsigned(cnt);
	nfsm_request(vp, NFSPROC_COMMIT, procp, cred);
	nfsm_wcc_data(vp, wccflag);
	if (!error) {
		nfsm_dissect(tl, u_long *, NFSX_V3WRITEVERF);
		if (bcmp((caddr_t)nmp->nm_verf, (caddr_t)tl,
			NFSX_V3WRITEVERF)) {
			bcopy((caddr_t)tl, (caddr_t)nmp->nm_verf,
				NFSX_V3WRITEVERF);
			error = NFSERR_STALEWRITEVERF;
		}
	}
	nfsm_reqdone;
	return (error);
}

/*
 * Kludge City..
 * - make nfs_bmap() essentially a no-op that does no translation
 * - do nfs_strategy() by doing I/O with nfs_readrpc/nfs_writerpc
 *   (Maybe I could use the process's page mapping, but I was concerned that
 *    Kernel Write might not be enabled and also figured copyout() would do
 *    a lot more work than bcopy() and also it currently happens in the
 *    context of the swapper process (2).
 */
static int
nfs_bmap(ap)
	struct vop_bmap_args /* {
		struct vnode *a_vp;
		daddr_t  a_bn;
		struct vnode **a_vpp;
		daddr_t *a_bnp;
		int *a_runp;
		int *a_runb;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	int devBlockSize = DEV_BSIZE;

	if (ap->a_vpp != NULL)
		*ap->a_vpp = vp;
	if (ap->a_bnp != NULL)
		*ap->a_bnp = ap->a_bn * btodb(vp->v_mount->mnt_stat.f_iosize,
					      devBlockSize);
	if (ap->a_runp != NULL)
		*ap->a_runp = 0;
#ifdef notyet
	if (ap->a_runb != NULL)
		*ap->a_runb = 0;
#endif
	return (0);
}

/*
 * Strategy routine.
 * For async requests when nfsiod(s) are running, queue the request by
 * calling nfs_asyncio(), otherwise just all nfs_doio() to do the
 * request.
 */
static int
nfs_strategy(ap)
	struct vop_strategy_args *ap;
{
	register struct buf *bp = ap->a_bp;
	struct ucred *cr;
	struct proc *p;
	int error = 0;

	if (ISSET(bp->b_flags, B_PHYS))
		panic("nfs_strategy: physio");
	if (ISSET(bp->b_flags, B_ASYNC))
		p = (struct proc *)0;
	else
		p = current_proc();	/* XXX */
	if (ISSET(bp->b_flags, B_READ))
		cr = bp->b_rcred;
	else
		cr = bp->b_wcred;
	/*
	 * If the op is asynchronous and an i/o daemon is waiting
	 * queue the request, wake it up and wait for completion
	 * otherwise just do it ourselves.
	 */
	if (!ISSET(bp->b_flags, B_ASYNC) || nfs_asyncio(bp, NOCRED))
		error = nfs_doio(bp, cr, p);
	return (error);
}

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

	return (EINVAL);
}

/*
 * fsync vnode op. Just call nfs_flush() with commit == 1.
 */
/* ARGSUSED */
static int
nfs_fsync(ap)
	struct vop_fsync_args /* {
		struct vnodeop_desc *a_desc;
		struct vnode * a_vp;
		struct ucred * a_cred;
		int  a_waitfor;
		struct proc * a_p;
	} */ *ap;
{

	return (nfs_flush(ap->a_vp, ap->a_cred, ap->a_waitfor, ap->a_p, 1));
}

/*
 * Flush all the blocks associated with a vnode.
 * 	Walk through the buffer pool and push any dirty pages
 *	associated with the vnode.
 */
static int
nfs_flush(vp, cred, waitfor, p, commit)
	register struct vnode *vp;
	struct ucred *cred;
	int waitfor;
	struct proc *p;
	int commit;
{
	register struct nfsnode *np = VTONFS(vp);
	register struct buf *bp;
	register int i;
	struct buf *nbp;
	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
	int s, error = 0, slptimeo = 0, slpflag = 0, retv, bvecpos, err;
	int passone = 1;
	u_quad_t off, endoff, toff;
	struct ucred* wcred = NULL;
	struct buf **bvec = NULL;
        void * object;
        kern_return_t kret;
        upl_t *upls = NULL;


#ifndef NFS_COMMITBVECSIZ
#define NFS_COMMITBVECSIZ	20
#endif
	struct buf *bvec_on_stack[NFS_COMMITBVECSIZ];
        struct upl_t *upls_on_stack[NFS_COMMITBVECSIZ]; 
        int bvecsize = 0, bveccount, buplpos;

	if (nmp->nm_flag & NFSMNT_INT)
		slpflag = PCATCH;
	if (!commit)
		passone = 0;

	/*
	 * A b_flags == (B_DELWRI | B_NEEDCOMMIT) block has been written to the
	 * server, but nas not been committed to stable storage on the server
	 * yet. On the first pass, the byte range is worked out and the commit
	 * rpc is done. On the second pass, nfs_writebp() is called to do the
	 * job.
	 */
again:
	if (vp->v_dirtyblkhd.lh_first)
		np->n_flag |= NMODIFIED;
	off = (u_quad_t)-1;
	endoff = 0;
	bvecpos = 0;
        buplpos = 0;
	if (NFS_ISV3(vp) && commit) {
		s = splbio();
		/*
		 * Count up how many buffers waiting for a commit.
		 */
		bveccount = 0;
		for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) {
			nbp = bp->b_vnbufs.le_next;
			if ((bp->b_flags & (B_BUSY | B_DELWRI | B_NEEDCOMMIT))
			    == (B_DELWRI | B_NEEDCOMMIT))
				bveccount++;
		}
		/*
		 * Allocate space to remember the list of bufs to commit.  It is
		 * important to use M_NOWAIT here to avoid a race with nfs_write.
		 * If we can't get memory (for whatever reason), we will end up
		 * committing the buffers one-by-one in the loop below.
		 */
		if (bveccount > NFS_COMMITBVECSIZ) {
			if (bvec != NULL && bvec != bvec_on_stack)
				_FREE(bvec, M_TEMP);
			MALLOC(bvec, struct buf **,
			       bveccount * sizeof(struct buf *), M_TEMP, M_NOWAIT);
			if (bvec == NULL) {
				bvec = bvec_on_stack;
				bvecsize = NFS_COMMITBVECSIZ;
			} else
				bvecsize = bveccount;
                        /* allocate the upl structure before the loop based on buffers to commit */
			if (upls != NULL && upls != upls_on_stack)
               			_FREE(upls, M_TEMP);
			MALLOC(upls, struct upl_t *,
                            bveccount * sizeof(upl_t), M_TEMP, M_NOWAIT);
                        if (upls == NULL)
                            upls = upls_on_stack;
		} else {
			if (bvec && bvec != bvec_on_stack)
				_FREE(bvec, M_TEMP);
			bvec = bvec_on_stack;
			bvecsize = NFS_COMMITBVECSIZ;
			if (upls && upls != upls_on_stack)
               			_FREE(upls, M_TEMP);
                        upls = upls_on_stack;
		}

		for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) {
			nbp = bp->b_vnbufs.le_next;
			if (bvecpos >= bvecsize)
				break;
			if ((bp->b_flags & (B_BUSY | B_DELWRI | B_NEEDCOMMIT))
				!= (B_DELWRI | B_NEEDCOMMIT))
				continue;
			bremfree(bp);
			/*
			 * Work out if all buffers are using the same cred
			 * so we can deal with them all with one commit.
			 */
			if (wcred == NULL)
				wcred = bp->b_wcred;
			else if (wcred != bp->b_wcred)
				wcred = NOCRED;
			SET(bp->b_flags, (B_BUSY | B_WRITEINPROG));

			/*
			 * we need vm_fault_list_request so if vm decides to
			 * do paging while we are waiting on commit rpc,
			 * that it doesn't pick these pages.
			 */
			if (!ISSET(bp->b_flags, B_PAGELIST)) {
				/* if pagelist exists, assume vm pages are locked/busy already */				off_t file_offset = ubc_blktooff(vp, bp->b_lblkno);
				object = ubc_getobject(vp, (UBC_NOREACTIVATE|UBC_HOLDOBJECT));
				if (object == (void*)NULL)
					panic("nfs_getcacheblk: NULL vmobject");
				if(bp->b_bufsize & 0xfff)
					panic("nfs_getcacheblk: list request is less than 4k");
				kret = vm_fault_list_request(
						object, (vm_object_offset_t)file_offset,
						bp->b_bufsize, &(upls[buplpos]), NULL, 0,
						(int)(UPL_NO_SYNC | UPL_CLEAN_IN_PLACE |UPL_PRECIOUS |
						UPL_SET_INTERNAL));
				if (kret != KERN_SUCCESS) 
					panic("nfs_getcacheblk: get pagelists failed with (%d)", kret);
                                    
#ifdef UBC_DEBUG
				upl_ubc_alias_set(pl, ioaddr, 1);
#endif /* UBC_DEBUG */
				buplpos++; /* not same as bvecpos if upl existed already */
			}

			/*
			 * A list of these buffers is kept so that the
			 * second loop knows which buffers have actually
			 * been committed. This is necessary, since there
			 * may be a race between the commit rpc and new
			 * uncommitted writes on the file.
			 */
			bvec[bvecpos++] = bp;
			toff = ((u_quad_t)bp->b_blkno) * DEV_BSIZE +
				bp->b_dirtyoff;
			if (toff < off)
				off = toff;
			toff += (u_quad_t)(bp->b_dirtyend - bp->b_dirtyoff);
			if (toff > endoff)
				endoff = toff;
		}
		splx(s);
	}
	if (bvecpos > 0) {
		/*
		 * Commit data on the server, as required.
		 * If all bufs are using the same wcred, then use that with
		 * one call for all of them, otherwise commit each one
		 * separately.
		 */
		if (wcred != NOCRED)
			retv = nfs_commit(vp, off, (int)(endoff - off),
					  wcred, p);
		else {
			retv = 0;
			for (i = 0; i < bvecpos; i++) {
				off_t off, size;
				bp = bvec[i];
				off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE +
					bp->b_dirtyoff;
				size = (u_quad_t)(bp->b_dirtyend
						  - bp->b_dirtyoff);
				retv = nfs_commit(vp, off, (int)size,
						  bp->b_wcred, p);
				if (retv) break;
			}
		}

		if (retv == NFSERR_STALEWRITEVERF)
			nfs_clearcommit(vp->v_mount);
                        
                for (i = 0; i < buplpos; i++) {
                    /*
                    * before the VOP_BWRITE and biodone(ASYNC)/brelse, we have to undo
                    * holding the vm page or we we will deadlock on another vm_fault_list_request.
                    * Here's a convenient place to put it. 
                    * Better if we could hold it by setting the PAGELIST flag and kernel_upl_map
                    * as does nfs_writebp. Then normal biodones and brelse will clean it up and 
                    * we can avoid this abort. For now make minimal changse and test this out.
                    */
                    err = kernel_upl_abort(upls[i], NULL); 
                    if (err)
                        printf("nfs_flush: kernel_upl_abort %d\n", err);
                    }

		/*
		 * Now, either mark the blocks I/O done or mark the
		 * blocks dirty, depending on whether the commit
		 * succeeded.
		 */
		for (i = 0; i < bvecpos; i++) {
                        
			bp = bvec[i];
			CLR(bp->b_flags, (B_NEEDCOMMIT | B_WRITEINPROG));
			if (retv) {
			    brelse(bp);
			} else {
			    vp->v_numoutput++;
			    SET(bp->b_flags, B_ASYNC);
			    s = splbio();
			    CLR(bp->b_flags, (B_READ|B_DONE|B_ERROR|B_DELWRI));
			    bp->b_dirtyoff = bp->b_dirtyend = 0;
			    reassignbuf(bp, vp);
			    splx(s);
			    biodone(bp);
			}
		}

	}

	/*
	 * Start/do any write(s) that are required.
         * There is a window here where B_BUSY protects the buffer. The vm pages have been
         * freed up, yet B_BUSY is set. Don't think you will hit any busy/incore problems while
         * we sleep, but not absolutely sure. Keep an eye on it. Otherwise we will have to hold
         * vm page across this locked. - EKN
	 */
loop:
	if (current_thread_aborted()) {
		error = EINTR;
		goto done;
	}
	s = splbio();
	for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) {
		nbp = bp->b_vnbufs.le_next;
		if (ISSET(bp->b_flags, B_BUSY)) {
			if (waitfor != MNT_WAIT || passone)
				continue;
			SET(bp->b_flags, B_WANTED);
			error = tsleep((caddr_t)bp, slpflag | (PRIBIO + 1),
				"nfsfsync", slptimeo);
			splx(s);
			if (error) {
			    if (nfs_sigintr(nmp, (struct nfsreq *)0, p)) {
				error = EINTR;
				goto done;
			    }
			    if (slpflag == PCATCH) {
				slpflag = 0;
				slptimeo = 2 * hz;
			    }
			}
			goto loop;
		}
		if (!ISSET(bp->b_flags, B_DELWRI))
			panic("nfs_fsync: not dirty");
		if ((passone || !commit) && ISSET(bp->b_flags, B_NEEDCOMMIT))
			continue;
		bremfree(bp);
		if (passone || !commit)
		    SET(bp->b_flags, (B_BUSY|B_ASYNC));
		else
		    SET(bp->b_flags, (B_BUSY|B_ASYNC|B_WRITEINPROG|B_NEEDCOMMIT));

		splx(s);
		VOP_BWRITE(bp);
		goto loop;
	}
	splx(s);
	if (passone) {
		passone = 0;
		goto again;
	}
	if (waitfor == MNT_WAIT) {
		while (vp->v_numoutput) {
			vp->v_flag |= VBWAIT;
			error = tsleep((caddr_t)&vp->v_numoutput,
				slpflag | (PRIBIO + 1), "nfsfsync", slptimeo);
			if (error) {
			    if (nfs_sigintr(nmp, (struct nfsreq *)0, p)) {
				error = EINTR;
				goto done;
			    }
			    if (slpflag == PCATCH) {
				slpflag = 0;
				slptimeo = 2 * hz;
			    }
			}
		}
		if (vp->v_dirtyblkhd.lh_first && commit) {
			goto loop;
		}
	}
	if (np->n_flag & NWRITEERR) {
		error = np->n_error;
		np->n_flag &= ~NWRITEERR;
	}
done:
	if (bvec != NULL && bvec != bvec_on_stack)
		_FREE(bvec, M_TEMP);
        if (upls != NULL && upls != upls_on_stack)
                _FREE(upls, M_TEMP);
	return (error);
}

/*
 * Return POSIX pathconf information applicable to nfs.
 *
 * The NFS V2 protocol doesn't support this, so just return EINVAL
 * for V2.
 */
/* ARGSUSED */
static int
nfs_pathconf(ap)
	struct vop_pathconf_args /* {
		struct vnode *a_vp;
		int a_name;
		int *a_retval;
	} */ *ap;
{

	return (EINVAL);
}

/*
 * NFS advisory byte-level locks.
 * Currently unsupported.
 */
static int
nfs_advlock(ap)
	struct vop_advlock_args /* {
		struct vnode *a_vp;
		caddr_t  a_id;
		int  a_op;
		struct flock *a_fl;
		int  a_flags;
	} */ *ap;
{
#ifdef __FreeBSD__
	register struct nfsnode *np = VTONFS(ap->a_vp);

	/*
	 * The following kludge is to allow diskless support to work
	 * until a real NFS lockd is implemented. Basically, just pretend
	 * that this is a local lock.
	 */
	return (lf_advlock(ap, &(np->n_lockf), np->n_size));
#else
#if DIAGNOSTIC
	printf("nfs_advlock: pid %d comm %s\n", current_proc()->p_pid, current_proc()->p_comm);
#endif
	return (EOPNOTSUPP);
#endif
}

/*
 * Print out the contents of an nfsnode.
 */
static int
nfs_print(ap)
	struct vop_print_args /* {
		struct vnode *a_vp;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct nfsnode *np = VTONFS(vp);

	printf("tag VT_NFS, fileid %ld fsid 0x%lx",
		np->n_vattr.va_fileid, np->n_vattr.va_fsid);
	if (vp->v_type == VFIFO)
		fifo_printinfo(vp);
	printf("\n");
	return (0);
}

/*
 * NFS directory offset lookup.
 * Currently unsupported.
 */
static int
nfs_blkatoff(ap)
	struct vop_blkatoff_args /* {
		struct vnode *a_vp;
		off_t a_offset;
		char **a_res;
		struct buf **a_bpp;
	} */ *ap;
{

#if DIAGNOSTIC
	printf("nfs_blkatoff: unimplemented!!");
#endif
	return (EOPNOTSUPP);
}

/*
 * NFS flat namespace allocation.
 * Currently unsupported.
 */
static int
nfs_valloc(ap)
	struct vop_valloc_args /* {
		struct vnode *a_pvp;
		int a_mode;
		struct ucred *a_cred;
		struct vnode **a_vpp;
	} */ *ap;
{

	return (EOPNOTSUPP);
}

/*
 * NFS flat namespace free.
 * Currently unsupported.
 */
static int
nfs_vfree(ap)
	struct vop_vfree_args /* {
		struct vnode *a_pvp;
		ino_t a_ino;
		int a_mode;
	} */ *ap;
{

#if DIAGNOSTIC
	printf("nfs_vfree: unimplemented!!");
#endif
	return (EOPNOTSUPP);
}

/*
 * NFS file truncation.
 */
static int
nfs_truncate(ap)
	struct vop_truncate_args /* {
		struct vnode *a_vp;
		off_t a_length;
		int a_flags;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{

	/* Use nfs_setattr */
#if DIAGNOSTIC
	printf("nfs_truncate: unimplemented!!");
#endif
	return (EOPNOTSUPP);
}

/*
 * NFS update.
 */
static int
nfs_update(ap)
	struct vop_update_args /* {
		struct vnode *a_vp;
		struct timeval *a_ta;
		struct timeval *a_tm;
		int a_waitfor;
	} */ *ap;
{

	/* Use nfs_setattr */
#if DIAGNOSTIC
	printf("nfs_update: unimplemented!!");
#endif
	return (EOPNOTSUPP);
}

int				nfs_aio_threads = 0; /* 1 per nfd (arbitrary) */
struct slock			nfs_aio_slock;
TAILQ_HEAD(bqueues, buf)	nfs_aio_bufq;
int				nfs_aio_bufq_len = 0; /* diagnostic only */

void
nfs_aio_thread()
{	/* see comment below in nfs_bwrite() for some rationale */
	struct buf	*bp;
	boolean_t funnel_state;

	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	for(;;) {
		simple_lock(&nfs_aio_slock);
		if ((bp = nfs_aio_bufq.tqh_first)) {
			TAILQ_REMOVE(&nfs_aio_bufq, bp, b_freelist);
			nfs_aio_bufq_len--;
			simple_unlock(&nfs_aio_slock);
			nfs_writebp(bp, 1);
		} else { /* nothing to do - goodnight */
			assert_wait(&nfs_aio_bufq, THREAD_UNINT);
			simple_unlock(&nfs_aio_slock);
			(void)tsleep((caddr_t)0, PRIBIO+1, "nfs_aio_bufq", 0);
		}
	}
	(void) thread_funnel_set(kernel_flock, FALSE);
}


void
nfs_aio_thread_init()
{
	if (nfs_aio_threads++ == 0) {
		simple_lock_init(&nfs_aio_slock);
		TAILQ_INIT(&nfs_aio_bufq);
	}
	kernel_thread(kernel_task, nfs_aio_thread);
}


/*
 * Just call nfs_writebp() with the force argument set to 1.
 */
static int
nfs_bwrite(ap)
	struct vop_bwrite_args /* {
		struct vnode *a_bp;
	} */ *ap;
{
	extern void wakeup_one(caddr_t chan);

	/*
	 * nfs_writebp will issue a synchronous rpc to if B_ASYNC then
	 * to avoid distributed deadlocks we handoff the write to the
	 * nfs_aio threads.  Doing so allows us to complete the
	 * current request, rather than blocking on a server which may
	 * be ourself (or blocked on ourself).
	 *
	 * Note the loopback deadlocks happened when the thread
	 * invoking us was nfsd, and also when it was the pagedaemon.
	 *
	 * This solution has one known problem.  If *ALL* buffers get
	 * on the nfs_aio queue then no forward progress can be made
	 * until one of those writes complete.  And if the current
	 * nfs_aio writes-in-progress block due to a non-responsive server we
	 * are in a deadlock circle.  Probably the cure is to limit the
	 * async write concurrency in getnewbuf as in FreeBSD 3.2.
	 */
	if (nfs_aio_threads && ISSET(ap->a_bp->b_flags, B_ASYNC)) {
		simple_lock(&nfs_aio_slock);
		nfs_aio_bufq_len++;
		TAILQ_INSERT_TAIL(&nfs_aio_bufq, ap->a_bp, b_freelist);
		simple_unlock(&nfs_aio_slock);
		wakeup_one((caddr_t)&nfs_aio_bufq);
		return (0);
	}
	return (nfs_writebp(ap->a_bp, 1));
}

/*
 * This is a clone of vn_bwrite(), except that B_WRITEINPROG isn't set unless
 * the force flag is one and it also handles the B_NEEDCOMMIT flag.
 */
int
nfs_writebp(bp, force)
	register struct buf *bp;
	int force;
{
	int s;
	register int oldflags = bp->b_flags, retv = 1;
	off_t off;
	upl_t upl;
	void * object;
	kern_return_t kret;
	struct vnode *vp = bp->b_vp;
	upl_page_info_t *pl;

	if(!ISSET(bp->b_flags, B_BUSY))
		panic("nfs_writebp: buffer is not busy???");

	s = splbio();
	CLR(bp->b_flags, (B_READ|B_DONE|B_ERROR|B_DELWRI));

	if (ISSET(oldflags, (B_ASYNC|B_DELWRI))) {
		reassignbuf(bp, vp);
	}

	vp->v_numoutput++;
	current_proc()->p_stats->p_ru.ru_oublock++;
	splx(s);
        
        /* 
         * Since the B_BUSY flag is set, we need to lock the page before doing nfs_commit.
         * Otherwise we may block and get a busy incore pages during a vm pageout.
         * Move the existing code up before the commit.
         */

        if (!ISSET(bp->b_flags, B_META) && UBCISVALID(vp)) {
    
            if (!ISSET(bp->b_flags, B_PAGELIST)) {

				off_t file_offset = ubc_blktooff(vp, bp->b_lblkno);

				object = ubc_getobject(vp, (UBC_NOREACTIVATE|UBC_HOLDOBJECT));
				if (object == (void*)NULL)
					panic("nfs_writebp: NULL vmobject");

				if(bp->b_bufsize & 0xfff)
					panic("nfs_writebp: list request is with less than 4k");
	
				kret = vm_fault_list_request(object, (vm_object_offset_t)file_offset, 
							bp->b_bufsize, &upl, NULL, 0, 
							(int)(UPL_NO_SYNC | UPL_CLEAN_IN_PLACE | UPL_PRECIOUS | UPL_SET_INTERNAL));
				if (kret != KERN_SUCCESS) {
					panic("nfs_writebp: get pagelists failed with (%d)", kret);
				}
                    
#ifdef UBC_DEBUG
                    upl_ubc_alias_set(pl, ioaddr, 2);
#endif /* UBC_DEBUG */

                    s = splbio();

                    pl = UPL_GET_INTERNAL_PAGE_LIST(upl);
                    bp->b_pagelist = upl;
                    SET(bp->b_flags, B_PAGELIST);
                    splx(s);
                    
                    kret = kernel_upl_map(kernel_map, upl, 
                            (vm_address_t *)&(bp->b_data));
                    if (kret != KERN_SUCCESS) {
                            panic("nfs_writebp: kernel_upl_map() failed with (%d)", kret);
                    }
                    if(bp->b_data == 0) 
                            panic("nfs_writebp: upl_map mapped 0");
                    if (!upl_page_present(pl, 0)) {
                            /* 
                                * may be the page got paged out.
                                * let's just read it in. It is marked
                                * busy so we should not have any one
                                * yanking this page underneath the fileIO
                                */
                            panic("nfs_writebp: nopage");
                    }
            }
        }

	/*
	 * If B_NEEDCOMMIT is set, a commit rpc may do the trick. If not
	 * an actual write will have to be scheduled via. VOP_STRATEGY().
	 * If B_WRITEINPROG is already set, then push it with a write anyhow.
	 */
	if ((oldflags & (B_NEEDCOMMIT | B_WRITEINPROG)) == B_NEEDCOMMIT) {
		off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff;
		SET(bp->b_flags, B_WRITEINPROG);
		retv = nfs_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff,
			bp->b_wcred, bp->b_proc);
		CLR(bp->b_flags, B_WRITEINPROG);
		if (!retv) {
			bp->b_dirtyoff = bp->b_dirtyend = 0;
			CLR(bp->b_flags, B_NEEDCOMMIT);
			biodone(bp);  /* on B_ASYNC will brelse the buffer */
                        
		} else if (retv == NFSERR_STALEWRITEVERF)
			nfs_clearcommit(vp->v_mount);
	}
	if (retv) {
		if (force)
			SET(bp->b_flags, B_WRITEINPROG);
                
                VOP_STRATEGY(bp);
                
	} 
        
	if( (oldflags & B_ASYNC) == 0) {
		int rtval = biowait(bp);

		if (oldflags & B_DELWRI) {
			s = splbio();
			reassignbuf(bp, vp);
			splx(s);
		}
		brelse(bp);
		return (rtval);
	} 

	return (0);
}

/*
 * nfs special file access vnode op.
 * Essentially just get vattr and then imitate iaccess() since the device is
 * local to the client.
 */
static int
nfsspec_access(ap)
	struct vop_access_args /* {
		struct vnode *a_vp;
		int  a_mode;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	register struct vattr *vap;
	register gid_t *gp;
	register struct ucred *cred = ap->a_cred;
	struct vnode *vp = ap->a_vp;
	mode_t mode = ap->a_mode;
	struct vattr vattr;
	register int i;
	int error;

	/*
	 * Disallow write attempts on filesystems mounted read-only;
	 * unless the file is a socket, fifo, or a block or character
	 * device resident on the filesystem.
	 */
	if ((mode & VWRITE) && (vp->v_mount->mnt_flag & MNT_RDONLY)) {
		switch (vp->v_type) {
		case VREG: case VDIR: case VLNK:
			return (EROFS);
		}
	}
	/*
	 * If you're the super-user,
	 * you always get access.
	 */
	if (cred->cr_uid == 0)
		return (0);
	vap = &vattr;
	error = VOP_GETATTR(vp, vap, cred, ap->a_p);
	if (error)
		return (error);
	/*
	 * Access check is based on only one of owner, group, public.
	 * If not owner, then check group. If not a member of the
	 * group, then check public access.
	 */
	if (cred->cr_uid != vap->va_uid) {
		mode >>= 3;
		gp = cred->cr_groups;
		for (i = 0; i < cred->cr_ngroups; i++, gp++)
			if (vap->va_gid == *gp)
				goto found;
		mode >>= 3;
found:
		;
	}
	error = (vap->va_mode & mode) == mode ? 0 : EACCES;
	return (error);
}

/*
 * Read wrapper for special devices.
 */
static int
nfsspec_read(ap)
	struct vop_read_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		int  a_ioflag;
		struct ucred *a_cred;
	} */ *ap;
{
	register struct nfsnode *np = VTONFS(ap->a_vp);

	/*
	 * Set access flag.
	 */
	np->n_flag |= NACC;
	np->n_atim.tv_sec = time.tv_sec;
	np->n_atim.tv_nsec = time.tv_usec * 1000;
	return (VOCALL(spec_vnodeop_p, VOFFSET(vop_read), ap));
}

/*
 * Write wrapper for special devices.
 */
static int
nfsspec_write(ap)
	struct vop_write_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		int  a_ioflag;
		struct ucred *a_cred;
	} */ *ap;
{
	register struct nfsnode *np = VTONFS(ap->a_vp);

	/*
	 * Set update flag.
	 */
	np->n_flag |= NUPD;
	np->n_mtim.tv_sec = time.tv_sec;
	np->n_mtim.tv_nsec = time.tv_usec * 1000;
	return (VOCALL(spec_vnodeop_p, VOFFSET(vop_write), ap));
}

/*
 * Close wrapper for special devices.
 *
 * Update the times on the nfsnode then do device close.
 */
static int
nfsspec_close(ap)
	struct vop_close_args /* {
		struct vnode *a_vp;
		int  a_fflag;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct nfsnode *np = VTONFS(vp);
	struct vattr vattr;

	if (np->n_flag & (NACC | NUPD)) {
		np->n_flag |= NCHG;
		if (vp->v_usecount == 1 &&
		    (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
			VATTR_NULL(&vattr);
			if (np->n_flag & NACC)
				vattr.va_atime = np->n_atim;
			if (np->n_flag & NUPD)
				vattr.va_mtime = np->n_mtim;
			(void)VOP_SETATTR(vp, &vattr, ap->a_cred, ap->a_p);
		}
	}
	return (VOCALL(spec_vnodeop_p, VOFFSET(vop_close), ap));
}

/*
 * Read wrapper for fifos.
 */
static int
nfsfifo_read(ap)
	struct vop_read_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		int  a_ioflag;
		struct ucred *a_cred;
	} */ *ap;
{
        extern vop_t **fifo_vnodeop_p;
	register struct nfsnode *np = VTONFS(ap->a_vp);

	/*
	 * Set access flag.
	 */
	np->n_flag |= NACC;
	np->n_atim.tv_sec = time.tv_sec;
	np->n_atim.tv_nsec = time.tv_usec * 1000;
	return (VOCALL(fifo_vnodeop_p, VOFFSET(vop_read), ap));
}

/*
 * Write wrapper for fifos.
 */
static int
nfsfifo_write(ap)
	struct vop_write_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		int  a_ioflag;
		struct ucred *a_cred;
	} */ *ap;
{
        extern vop_t **fifo_vnodeop_p;
	register struct nfsnode *np = VTONFS(ap->a_vp);

	/*
	 * Set update flag.
	 */
	np->n_flag |= NUPD;
	np->n_mtim.tv_sec = time.tv_sec;
	np->n_mtim.tv_nsec = time.tv_usec * 1000;
	return (VOCALL(fifo_vnodeop_p, VOFFSET(vop_write), ap));
}

/*
 * Close wrapper for fifos.
 *
 * Update the times on the nfsnode then do fifo close.
 */
static int
nfsfifo_close(ap)
	struct vop_close_args /* {
		struct vnode *a_vp;
		int  a_fflag;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	register struct nfsnode *np = VTONFS(vp);
	struct vattr vattr;
        extern vop_t **fifo_vnodeop_p;

	if (np->n_flag & (NACC | NUPD)) {
		if (np->n_flag & NACC) {
			np->n_atim.tv_sec = time.tv_sec;
			np->n_atim.tv_nsec = time.tv_usec * 1000;
		}
		if (np->n_flag & NUPD) {
			np->n_mtim.tv_sec = time.tv_sec;
			np->n_mtim.tv_nsec = time.tv_usec * 1000;
		}
		np->n_flag |= NCHG;
		if (vp->v_usecount == 1 &&
		    (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
			VATTR_NULL(&vattr);
			if (np->n_flag & NACC)
				vattr.va_atime = np->n_atim;
			if (np->n_flag & NUPD)
				vattr.va_mtime = np->n_mtim;
			(void)VOP_SETATTR(vp, &vattr, ap->a_cred, ap->a_p);
		}
	}
	return (VOCALL(fifo_vnodeop_p, VOFFSET(vop_close), ap));
}

static int
nfs_ioctl(ap)
	struct vop_ioctl_args *ap;
{

	/*
	 * XXX we were once bogusly enoictl() which returned this (ENOTTY).
	 * Probably we should return ENODEV.
	 */
	return (ENOTTY);
}

static int
nfs_select(ap)
	struct vop_select_args *ap;
{

	/*
	 * We were once bogusly seltrue() which returns 1.  Is this right?
	 */
	return (1);
}

/* XXX Eliminate use of struct bp here */
/*
 * Vnode op for pagein using getblk_pages
 * derived from nfs_bioread()
 * No read aheads are started from pagein operation
 */
static int
nfs_pagein(ap)
	struct vop_pagein_args /* {
	   	struct vnode *a_vp,
	   	upl_t 	a_pl,
		vm_offset_t   a_pl_offset,
		off_t         a_f_offset,
		size_t        a_size,
		struct ucred *a_cred,
		int           a_flags
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	upl_t pl = ap->a_pl;
	size_t size= ap->a_size;
	off_t f_offset = ap->a_f_offset;
	vm_offset_t pl_offset = ap->a_pl_offset;
	int flags  = ap->a_flags;
	struct ucred *cred;
	register struct nfsnode *np = VTONFS(vp);
	register int biosize;
	register int xsize;
	struct vattr vattr;
	struct proc *p = current_proc();
	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
	int error = 0;
	vm_offset_t ioaddr;
	struct uio	auio;
	struct iovec	aiov;
	struct uio * uio = &auio;
	int nocommit = flags & UPL_NOCOMMIT;

	KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 322)) | DBG_FUNC_NONE,
		     (int)f_offset, size, pl, pl_offset, 0);

	if (UBCINVALID(vp)) {
#if DIAGNOSTIC
		panic("nfs_pagein: invalid vp");
#endif /* DIAGNOSTIC */
		return (EPERM);
	}

	UBCINFOCHECK("nfs_pagein", vp);
	if(pl == (upl_t)NULL) {
		panic("nfs_pagein: no upl");
	}

	cred = ubc_getcred(vp);
	if (cred == NOCRED)
		cred = ap->a_cred;

	if (size <= 0)
		return (EINVAL);

	if (f_offset < 0 || f_offset >= np->n_size 
					|| (f_offset & PAGE_MASK_64)) {
		if (!nocommit)
			kernel_upl_abort_range(pl, pl_offset, size, 
				UPL_ABORT_ERROR | UPL_ABORT_FREE_ON_EMPTY);
		return (EINVAL);
	}

	auio.uio_iov = &aiov;
	auio.uio_iovcnt = 1;
	auio.uio_offset = f_offset;
	auio.uio_segflg = UIO_SYSSPACE;
	auio.uio_rw = UIO_READ;
	auio.uio_procp = NULL;


	if ((nmp->nm_flag & (NFSMNT_NFSV3 | NFSMNT_GOTFSINFO)) == NFSMNT_NFSV3)
		(void)nfs_fsinfo(nmp, vp, cred, p);
	biosize = min(vp->v_mount->mnt_stat.f_iosize, size);

	if (biosize & PAGE_MASK)
	        panic("nfs_pagein(%x): biosize not page aligned", biosize);

#if 0 /* Why bother? */
/* DO NOT BOTHER WITH "approximately maintained cache consistency" */
/* Does not make sense in paging paths -- Umesh*/
	/*
	 * For nfs, cache consistency can only be maintained approximately.
	 * Although RFC1094 does not specify the criteria, the following is
	 * believed to be compatible with the reference port.
	 * For nqnfs, full cache consistency is maintained within the loop.
	 * For nfs:
	 * If the file's modify time on the server has changed since the
	 * last read rpc or you have written to the file,
	 * you may have lost data cache consistency with the
	 * server, so flush all of the file's data out of the cache.
	 * Then force a getattr rpc to ensure that you have up to date
	 * attributes.
	 * NB: This implies that cache data can be read when up to
	 * NFS_ATTRTIMEO seconds out of date. If you find that you need current
	 * attributes this could be forced by setting n_attrstamp to 0 before
	 * the VOP_GETATTR() call.
	 */
	if ((nmp->nm_flag & NFSMNT_NQNFS) == 0) {
		if (np->n_flag & NMODIFIED) {
			np->n_attrstamp = 0;
			error = VOP_GETATTR(vp, &vattr, cred, p);
			if (error) {
				if (!nocommit)
					kernel_upl_abort_range(pl, pl_offset, 
						size, 
						UPL_ABORT_ERROR |
						UPL_ABORT_FREE_ON_EMPTY);
				return (error);
			}
			np->n_mtime = vattr.va_mtime.tv_sec;
		} else {
			error = VOP_GETATTR(vp, &vattr, cred, p);
			if (error){
				if (!nocommit)
					kernel_upl_abort_range(pl, pl_offset, size,  
						UPL_ABORT_ERROR |
						UPL_ABORT_FREE_ON_EMPTY);
				return (error);
			}
			if (np->n_mtime != vattr.va_mtime.tv_sec) {
				error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
				if (error){
				        if (!nocommit)
					        kernel_upl_abort_range(pl, pl_offset, size, 
								UPL_ABORT_ERROR |
								UPL_ABORT_FREE_ON_EMPTY);
					return (error);
				}
				np->n_mtime = vattr.va_mtime.tv_sec;
			}
		}
	}
#endif 0 /* Why bother? */

	kernel_upl_map(kernel_map, pl, &ioaddr);
	ioaddr += pl_offset;
	xsize = size;

	do {
		uio->uio_resid = min(biosize, xsize);
		aiov.iov_len  = uio->uio_resid;
		aiov.iov_base = (caddr_t)ioaddr;

		KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 322)) | DBG_FUNC_NONE,
			(int)uio->uio_offset, uio->uio_resid, ioaddr, xsize, 0);

#warning nfs_pagein does not support NQNFS yet.
#if 0 /* why bother? */
/* NO RESOURCES TO FIX NQNFS CASE */
/* We need to deal with this later -- Umesh */
		/*
		 * Get a valid lease. If cached data is stale, flush it.
		 */
		if (nmp->nm_flag & NFSMNT_NQNFS) {
			if (NQNFS_CKINVALID(vp, np, ND_READ)) {
				do {
					error = nqnfs_getlease(vp, ND_READ, cred, p);
				} while (error == NQNFS_EXPIRED);
				if (error){
					kernel_upl_unmap(kernel_map, pl);
					if (!nocommit)
						kernel_upl_abort_range(pl, pl_offset,
							size ,UPL_ABORT_ERROR |
						UPL_ABORT_FREE_ON_EMPTY);

					return (error);
				}
				if (np->n_lrev != np->n_brev ||
					(np->n_flag & NQNFSNONCACHE)) {
					error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
					if (error) {
						kernel_upl_unmap(kernel_map, pl);
					if (!nocommit)
						kernel_upl_abort_range(pl,
								pl_offset,size ,
								UPL_ABORT_ERROR | UPL_ABORT_FREE_ON_EMPTY);
						return (error);
					}
					np->n_brev = np->n_lrev;
				}
			}
		}
#endif 0 /* why bother? */

		if (np->n_flag & NQNFSNONCACHE) {
			error = nfs_readrpc(vp, uio, cred);
			kernel_upl_unmap(kernel_map, pl);

			if (!nocommit) {
				if(error) 
					kernel_upl_abort_range(pl, pl_offset, size ,
						UPL_ABORT_ERROR | UPL_ABORT_FREE_ON_EMPTY);
				else
					kernel_upl_commit_range(pl, 
						pl_offset, size, 
						UPL_COMMIT_CLEAR_DIRTY 
						   | UPL_COMMIT_FREE_ON_EMPTY,
						UPL_GET_INTERNAL_PAGE_LIST(pl),
						MAX_UPL_TRANSFER);
			}
			return (error);
		}

		/*
		 * With UBC we get here only when the file data is not in the VM
		 * page cache, so go ahead and read in.
		 */
#ifdef UBC_DEBUG
		upl_ubc_alias_set(pl, ioaddr, 2);
#endif /* UBC_DEBUG */
		nfsstats.pageins++;
		error = nfs_readrpc(vp, uio, cred);

		if (!error) {
			int zoff;
			int zcnt;

			if (uio->uio_resid) {
				/*
				 * If uio_resid > 0, there is a hole in the file and
				 * no writes after the hole have been pushed to
				 * the server yet... or we're at the EOF
				 * Just zero fill the rest of the valid area.
				 */
				zcnt = uio->uio_resid;
				zoff = biosize - zcnt;
				bzero((char *)ioaddr + zoff, zcnt);

				KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 324)) | DBG_FUNC_NONE,
					(int)uio->uio_offset, zoff, zcnt, ioaddr, 0);

				uio->uio_offset += zcnt;
			}
			ioaddr += biosize;	
			xsize  -= biosize;
		} else
			KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 322)) | DBG_FUNC_NONE,
				(int)uio->uio_offset, uio->uio_resid, error, -1, 0);

		if (p && (vp->v_flag & VTEXT) &&
				(((nmp->nm_flag & NFSMNT_NQNFS) &&
				NQNFS_CKINVALID(vp, np, ND_READ) &&
				np->n_lrev != np->n_brev) ||
				(!(nmp->nm_flag & NFSMNT_NQNFS) &&
				np->n_mtime != np->n_vattr.va_mtime.tv_sec))) { 
			uprintf("Process killed due to text file modification\n");
			psignal(p, SIGKILL);
			p->p_flag |= P_NOSWAP;
		}

	} while (error == 0 && xsize > 0);

	kernel_upl_unmap(kernel_map, pl);

	if (!nocommit) {
		if (error) 
			kernel_upl_abort_range(pl, pl_offset, size, 
				UPL_ABORT_ERROR |  UPL_ABORT_FREE_ON_EMPTY);
		else
			kernel_upl_commit_range(pl, pl_offset, size,
				UPL_COMMIT_CLEAR_DIRTY 
						| UPL_COMMIT_FREE_ON_EMPTY,
				UPL_GET_INTERNAL_PAGE_LIST(pl), 
				MAX_UPL_TRANSFER);
	}

	return (error);
}

/*
 * Vnode op for pageout using UPL
 * Derived from nfs_write()
 * File size changes are not permitted in pageout.
 */
static int
nfs_pageout(ap)
	struct vop_pageout_args /* {
		struct vnode *a_vp,
		upl_t 	a_pl,
		vm_offset_t   a_pl_offset,
		off_t         a_f_offset,
		size_t        a_size,
		struct ucred *a_cred,
		int           a_flags
	} */ *ap;
{
	register struct vnode *vp = ap->a_vp;
	upl_t pl = ap->a_pl;
	size_t size= ap->a_size;
	off_t f_offset = ap->a_f_offset;
	vm_offset_t pl_offset = ap->a_pl_offset;
	int flags  = ap->a_flags;
	int ioflag = ap->a_flags;
	register int biosize;
	struct proc *p = current_proc();
	struct nfsnode *np = VTONFS(vp);
	register struct ucred *cred;
	struct buf *bp;
	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
	daddr_t lbn;
	int bufsize;
	int n = 0, on, error = 0, iomode, must_commit, s;
	off_t off;
	vm_offset_t ioaddr;
	struct uio	auio;
	struct iovec	aiov;
	struct uio * uio = &auio;
	int nocommit = flags & UPL_NOCOMMIT;
	int iosize;
	int pgsize;

	KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 323)) | DBG_FUNC_NONE,
		(int)f_offset, size, pl, pl_offset, 0);

	if (UBCINVALID(vp)) {
#if DIAGNOSTIC
		panic("nfs_pageout: invalid vnode");
#endif
		return (EIO);
	}
	UBCINFOCHECK("nfs_pageout", vp);

	if (size <= 0)
		return (EINVAL);

	if (pl == (upl_t)NULL) {
		panic("nfs_pageout: no upl");
	}

	/*
	 * I use nm_rsize, not nm_wsize so that all buffer cache blocks
	 * will be the same size within a filesystem. nfs_writerpc will
	 * still use nm_wsize when sizing the rpc's.
	 */
        biosize = min(vp->v_mount->mnt_stat.f_iosize, size);

        if (biosize & PAGE_MASK)
                panic("nfs_pageout(%x): biosize not page aligned", biosize);


	/*
	 * Check to see whether the buffer is incore
	 * If incore and not busy invalidate it from the cache
	 * we should not find it BUSY, since we always do a 
	 * vm_fault_list_request in 'getblk' before returning
	 * which would block on the page busy status
	 */
        lbn = f_offset / PAGE_SIZE; /* to match the size getblk uses */
        
	for (iosize = size; iosize > 0; iosize -= PAGE_SIZE, lbn++) {

		s = splbio();
		if (bp = incore(vp, lbn)) {
			if (ISSET(bp->b_flags, B_BUSY)) {
                                /* don't panic incore. just tell vm we are busy */
				(void) kernel_upl_abort(pl, NULL); 
                                return(EBUSY);
                                };

			bremfree(bp);
			SET(bp->b_flags, (B_BUSY | B_INVAL));
			brelse(bp);
		}
		splx(s);
	}

	cred = ubc_getcred(vp);
	if (cred == NOCRED)
		cred = ap->a_cred;

	if (np->n_flag & NWRITEERR) {
		np->n_flag &= ~NWRITEERR;
		if (!nocommit)
			kernel_upl_abort_range(pl, pl_offset, size, 
				UPL_ABORT_FREE_ON_EMPTY);
		return (np->n_error);
	}
	if ((nmp->nm_flag & (NFSMNT_NFSV3 | NFSMNT_GOTFSINFO)) == NFSMNT_NFSV3)
		(void)nfs_fsinfo(nmp, vp, cred, p);

	if (f_offset < 0 || f_offset >= np->n_size ||
	   (f_offset & PAGE_MASK_64) || (size & PAGE_MASK)) {
		if (!nocommit)
			kernel_upl_abort_range(pl, pl_offset, size, 
				UPL_ABORT_FREE_ON_EMPTY);
		return (EINVAL);
	}

	kernel_upl_map(kernel_map, pl, &ioaddr);

	if ((f_offset + size) > np->n_size)
		iosize = np->n_size - f_offset;
	else
		iosize = size;

	pgsize = (iosize + (PAGE_SIZE - 1)) & ~PAGE_MASK;

	if (size > pgsize) {
		if (!nocommit)
			kernel_upl_abort_range(pl, pl_offset + pgsize, size - pgsize,
				UPL_ABORT_FREE_ON_EMPTY);
	}
	auio.uio_iov = &aiov;
	auio.uio_iovcnt = 1;
	auio.uio_offset = f_offset;
	auio.uio_segflg = UIO_SYSSPACE;
	auio.uio_rw = UIO_READ;
	auio.uio_resid = iosize;
	auio.uio_procp = NULL;

	aiov.iov_len = iosize;
	aiov.iov_base = (caddr_t)ioaddr + pl_offset;

	/* 
	 * check for partial page and clear the
	 * contents past end of the file before
	 * releasing it in the VM page cache
	 */
	if ((f_offset < np->n_size) && (f_offset + size) > np->n_size) {
		size_t io = np->n_size - f_offset;

		bzero((caddr_t)(ioaddr + pl_offset + io), size - io);

		KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 321)) | DBG_FUNC_NONE,
			(int)np->n_size, (int)f_offset, (int)f_offset + io, size - io, 0);
	}

	do {

#warning nfs_pageout does not support NQNFS yet.
#if 0 /* why bother? */
/* NO RESOURCES TO FIX NQNFS CASE */
/* We need to deal with this later -- Umesh */

		/*
		 * Check for a valid write lease.
		 */
		if ((nmp->nm_flag & NFSMNT_NQNFS) &&
		    NQNFS_CKINVALID(vp, np, ND_WRITE)) {
			do {
				error = nqnfs_getlease(vp, ND_WRITE, cred, p);
			} while (error == NQNFS_EXPIRED);
			if (error) {
				kernel_upl_unmap(kernel_map, pl);
				if (!nocommit)
					kernel_upl_abort_range(pl, pl_offset, size, 
						UPL_ABORT_FREE_ON_EMPTY);
				return (error);
			}
			if (np->n_lrev != np->n_brev ||
			    (np->n_flag & NQNFSNONCACHE)) {
				error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
				if (error) {
					kernel_upl_unmap(kernel_map, pl);
					if (!nocommit)
						kernel_upl_abort_range(pl, 
						pl_offset, size, 
					 	UPL_ABORT_FREE_ON_EMPTY);
					return (error);
				}
				np->n_brev = np->n_lrev;
			}
		}
#endif 0 /* why bother? */

		if ((np->n_flag & NQNFSNONCACHE) && uio->uio_iovcnt == 1) {
			iomode = NFSV3WRITE_FILESYNC;
			error = nfs_writerpc(vp, uio, cred, &iomode, &must_commit);
			if (must_commit)
				nfs_clearcommit(vp->v_mount);
			kernel_upl_unmap(kernel_map, pl);
                        
                        /* see comments below after other nfs_writerpc and ESTALE */
                        if (error == ESTALE) {
                            kernel_upl_abort_range(pl, pl_offset, size, 
                                UPL_ABORT_DUMP_PAGES|UPL_ABORT_FREE_ON_EMPTY);
                        } else {
                            if (!nocommit) {
                                if(error)
                                    kernel_upl_abort_range(pl, pl_offset, size, 
                                    UPL_ABORT_FREE_ON_EMPTY);
                                else
                                    kernel_upl_commit_range(pl, 
                                        pl_offset, size, 
                                        UPL_COMMIT_CLEAR_DIRTY | UPL_COMMIT_FREE_ON_EMPTY,
                                        UPL_GET_INTERNAL_PAGE_LIST(pl), MAX_UPL_TRANSFER);
                            }
                        }
			return (error);
		}
		nfsstats.pageouts++;
		lbn = uio->uio_offset / biosize;
		on = uio->uio_offset & (biosize-1);
		n = min((unsigned)(biosize - on), uio->uio_resid);
again:
		bufsize = biosize;
#if 0
		if ((lbn + 1) * biosize > np->n_size) {
			bufsize = np->n_size - lbn * biosize;
			bufsize = (bufsize + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1);
		}
#endif
		vp->v_numoutput++;

		np->n_flag |= NMODIFIED;

#if 0 /* why bother? */
/* NO RESOURCES TO FIX NQNFS CASE */
/* We need to deal with this later -- Umesh */
		/*
		 * Check for valid write lease and get one as required.
		 * In case getblk() and/or bwrite() delayed us.
		 */
		if ((nmp->nm_flag & NFSMNT_NQNFS) &&
		    NQNFS_CKINVALID(vp, np, ND_WRITE)) {
			do {
				error = nqnfs_getlease(vp, ND_WRITE, cred, p);
			} while (error == NQNFS_EXPIRED);
			if (error)
				goto cleanup;

			if (np->n_lrev != np->n_brev ||
			    (np->n_flag & NQNFSNONCACHE)) {
					error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
					if (error) {
						kernel_upl_unmap(kernel_map, pl);
						if (!nocommit)
							kernel_upl_abort_range(pl, 
							pl_offset,
					 		size,
						  UPL_ABORT_FREE_ON_EMPTY);

						return (error);
					}
					np->n_brev = np->n_lrev;
					goto again;
			}
		}
#endif 0 /* why bother? */

		iomode = NFSV3WRITE_FILESYNC;
		error = nfs_writerpc(vp, uio, cred, &iomode, &must_commit);
		if (must_commit)
			nfs_clearcommit(vp->v_mount);
		vp->v_numoutput--;

		if (error)
			goto cleanup;

		if (n > 0) {
			uio->uio_resid -= n;
			uio->uio_offset += n;
			uio->uio_iov->iov_base += n;
			uio->uio_iov->iov_len -= n;
		}
	} while (uio->uio_resid > 0 && n > 0);

cleanup:
	kernel_upl_unmap(kernel_map, pl);
	/* 
	* EStale is special. In this case, we want vm to dump out
	* the pages. Better yet, sever the object so we don't come
	* back here on each page of the object to page out. For now,
	* just dump. 
	* XXX What about !nocommit case? Should ESTALE only be checked
	* in that portion? - EKN
	*/
	if (error == ESTALE) {
            kernel_upl_abort_range(pl, pl_offset, size, 
                UPL_ABORT_DUMP_PAGES|UPL_ABORT_FREE_ON_EMPTY);
	} else {
            if (!nocommit) {
                if(error)
                    kernel_upl_abort_range(pl, pl_offset, pgsize, 
                        UPL_ABORT_FREE_ON_EMPTY);
                else
                    kernel_upl_commit_range(pl, pl_offset, pgsize,
                        UPL_COMMIT_CLEAR_DIRTY | UPL_COMMIT_FREE_ON_EMPTY,
                    UPL_GET_INTERNAL_PAGE_LIST(pl), MAX_UPL_TRANSFER);
            }
	}

	return (error);
}

/* Blktooff derives file offset given a logical block number */
static int
nfs_blktooff(ap)
	struct vop_blktooff_args /* {
		struct vnode *a_vp;
		daddr_t a_lblkno;
		off_t *a_offset;    
	} */ *ap;
{
	int biosize;
	register struct vnode *vp = ap->a_vp;

	biosize = min(vp->v_mount->mnt_stat.f_iosize, PAGE_SIZE); /* nfs_bio.c */

	*ap->a_offset = (off_t)(ap->a_lblkno *  biosize);

	return (0);
}

/* Blktooff derives file offset given a logical block number */
static int
nfs_offtoblk(ap)
	struct vop_offtoblk_args /* {
		struct vnode *a_vp;
		off_t a_offset;    
		daddr_t *a_lblkno;
	} */ *ap;
{
	int biosize;
	register struct vnode *vp = ap->a_vp;

	biosize = min(vp->v_mount->mnt_stat.f_iosize, PAGE_SIZE); /* nfs_bio.c */

	*ap->a_lblkno = (daddr_t)(ap->a_offset /  biosize);

	return (0);
}
static int
nfs_cmap(ap)
	struct vop_cmap_args /* {
		struct vnode *a_vp;
		off_t a_offset;    
		size_t a_size;
		daddr_t *a_bpn;
		size_t *a_run;
		void *a_poff;
	} */ *ap;
{
	return (EOPNOTSUPP);
}