kern/sys: Import NFS and NFS file system client

Update #4475

1 files changed, 1086 insertions, 0 deletions

diff --git a/freebsd/sys/fs/nfs/nfsport.h b/freebsd/sys/fs/nfs/nfsport.h
new file mode 100644
index 00000000..8abb6a5d
--- /dev/null
+++ b/freebsd/sys/fs/nfs/nfsport.h
@@ -0,0 +1,1086 @@
+/*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * 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. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _NFS_NFSPORT_H_
+#define	_NFS_NFSPORT_H_
+
+/*
+ * In general, I'm not fond of #includes in .h files, but this seems
+ * to be the cleanest way to handle #include files for the ports.
+ */
+#ifdef _KERNEL
+#include <sys/unistd.h>
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/conf.h>
+#include <sys/dirent.h>
+#include <sys/domain.h>
+#include <sys/fcntl.h>
+#include <sys/file.h>
+#include <sys/filedesc.h>
+#include <sys/jail.h>
+#include <sys/kernel.h>
+#include <sys/lockf.h>
+#include <sys/malloc.h>
+#include <sys/mbuf.h>
+#include <sys/mount.h>
+#include <sys/mutex.h>
+#include <sys/namei.h>
+#include <sys/proc.h>
+#include <sys/protosw.h>
+#include <sys/reboot.h>
+#include <sys/resourcevar.h>
+#include <sys/signalvar.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/stat.h>
+#include <sys/syslog.h>
+#include <sys/sysproto.h>
+#include <sys/time.h>
+#include <sys/uio.h>
+#include <sys/vnode.h>
+#include <sys/bio.h>
+#include <sys/buf.h>
+#include <sys/acl.h>
+#include <sys/module.h>
+#include <sys/sysent.h>
+#include <sys/syscall.h>
+#include <sys/priv.h>
+#include <sys/kthread.h>
+#include <sys/syscallsubr.h>
+#include <net/if.h>
+#include <net/if_var.h>
+#include <net/radix.h>
+#include <net/route.h>
+#include <net/if_dl.h>
+#include <netinet/in.h>
+#include <netinet/in_pcb.h>
+#include <netinet/in_systm.h>
+#include <netinet/in_var.h>
+#include <netinet/ip.h>
+#include <netinet/ip_var.h>
+#include <netinet/tcp.h>
+#include <netinet/tcp_fsm.h>
+#include <netinet/tcp_seq.h>
+#include <netinet/tcp_timer.h>
+#include <netinet/tcp_var.h>
+#include <machine/in_cksum.h>
+#include <crypto/des/des.h>
+#include <sys/md5.h>
+#include <rpc/rpc.h>
+#include <rpc/rpcsec_gss.h>
+
+/*
+ * For Darwin, these functions should be "static" when built in a kext.
+ * (This is always defined as nil otherwise.)
+ */
+#define	APPLESTATIC
+#include <ufs/ufs/dir.h>
+#include <ufs/ufs/quota.h>
+#include <ufs/ufs/inode.h>
+#include <ufs/ufs/extattr.h>
+#include <ufs/ufs/ufsmount.h>
+#include <vm/uma.h>
+#include <vm/vm.h>
+#include <vm/vm_object.h>
+#include <vm/vm_extern.h>
+#include <nfs/nfssvc.h>
+#include "opt_nfs.h"
+#include "opt_ufs.h"
+
+/*
+ * These types must be defined before the nfs includes.
+ */
+#define	NFSSOCKADDR_T	struct sockaddr *
+#define	NFSPROC_T	struct thread
+#define	NFSDEV_T	dev_t
+#define	NFSSVCARGS	nfssvc_args
+#define	NFSACL_T	struct acl
+
+/*
+ * These should be defined as the types used for the corresponding VOP's
+ * argument type.
+ */
+#define	NFS_ACCESS_ARGS		struct vop_access_args
+#define	NFS_OPEN_ARGS		struct vop_open_args
+#define	NFS_GETATTR_ARGS	struct vop_getattr_args
+#define	NFS_LOOKUP_ARGS		struct vop_lookup_args
+#define	NFS_READDIR_ARGS	struct vop_readdir_args
+
+/*
+ * Allocate mbufs. Must succeed and never set the mbuf ptr to NULL.
+ */
+#define	NFSMGET(m)	do { 					\
+		MGET((m), M_WAITOK, MT_DATA); 			\
+		while ((m) == NULL ) { 				\
+			(void) nfs_catnap(PZERO, 0, "nfsmget");	\
+			MGET((m), M_WAITOK, MT_DATA); 		\
+		} 						\
+	} while (0)
+#define	NFSMGETHDR(m)	do { 					\
+		MGETHDR((m), M_WAITOK, MT_DATA);		\
+		while ((m) == NULL ) { 				\
+			(void) nfs_catnap(PZERO, 0, "nfsmget");	\
+			MGETHDR((m), M_WAITOK, MT_DATA); 	\
+		} 						\
+	} while (0)
+#define	NFSMCLGET(m, w)	do { 					\
+		MGET((m), M_WAITOK, MT_DATA); 			\
+		while ((m) == NULL ) { 				\
+			(void) nfs_catnap(PZERO, 0, "nfsmget");	\
+			MGET((m), M_WAITOK, MT_DATA); 		\
+		} 						\
+		MCLGET((m), (w));				\
+	} while (0)
+#define	NFSMCLGETHDR(m, w) do { 				\
+		MGETHDR((m), M_WAITOK, MT_DATA);		\
+		while ((m) == NULL ) { 				\
+			(void) nfs_catnap(PZERO, 0, "nfsmget");	\
+			MGETHDR((m), M_WAITOK, MT_DATA); 	\
+		} 						\
+	} while (0)
+#define	NFSMTOD	mtod
+
+/*
+ * Client side constant for size of a lockowner name.
+ */
+#define	NFSV4CL_LOCKNAMELEN	12
+
+/*
+ * Type for a mutex lock.
+ */
+#define	NFSMUTEX_T		struct mtx
+
+#endif	/* _KERNEL */
+
+/*
+ * NFSv4 Operation numbers.
+ */
+#define	NFSV4OP_ACCESS		3
+#define	NFSV4OP_CLOSE		4
+#define	NFSV4OP_COMMIT		5
+#define	NFSV4OP_CREATE		6
+#define	NFSV4OP_DELEGPURGE	7
+#define	NFSV4OP_DELEGRETURN	8
+#define	NFSV4OP_GETATTR		9
+#define	NFSV4OP_GETFH		10
+#define	NFSV4OP_LINK		11
+#define	NFSV4OP_LOCK		12
+#define	NFSV4OP_LOCKT		13
+#define	NFSV4OP_LOCKU		14
+#define	NFSV4OP_LOOKUP		15
+#define	NFSV4OP_LOOKUPP		16
+#define	NFSV4OP_NVERIFY		17
+#define	NFSV4OP_OPEN		18
+#define	NFSV4OP_OPENATTR	19
+#define	NFSV4OP_OPENCONFIRM	20
+#define	NFSV4OP_OPENDOWNGRADE	21
+#define	NFSV4OP_PUTFH		22
+#define	NFSV4OP_PUTPUBFH	23
+#define	NFSV4OP_PUTROOTFH	24
+#define	NFSV4OP_READ		25
+#define	NFSV4OP_READDIR		26
+#define	NFSV4OP_READLINK	27
+#define	NFSV4OP_REMOVE		28
+#define	NFSV4OP_RENAME		29
+#define	NFSV4OP_RENEW		30
+#define	NFSV4OP_RESTOREFH	31
+#define	NFSV4OP_SAVEFH		32
+#define	NFSV4OP_SECINFO		33
+#define	NFSV4OP_SETATTR		34
+#define	NFSV4OP_SETCLIENTID	35
+#define	NFSV4OP_SETCLIENTIDCFRM	36
+#define	NFSV4OP_VERIFY		37
+#define	NFSV4OP_WRITE		38
+#define	NFSV4OP_RELEASELCKOWN	39
+
+/*
+ * Must be one greater than the last Operation#.
+ */
+#define	NFSV4OP_NOPS		40
+
+/*
+ * Additional Ops for NFSv4.1.
+ */
+#define	NFSV4OP_BACKCHANNELCTL	40
+#define	NFSV4OP_BINDCONNTOSESS	41
+#define	NFSV4OP_EXCHANGEID	42
+#define	NFSV4OP_CREATESESSION	43
+#define	NFSV4OP_DESTROYSESSION	44
+#define	NFSV4OP_FREESTATEID	45
+#define	NFSV4OP_GETDIRDELEG	46
+#define	NFSV4OP_GETDEVINFO	47
+#define	NFSV4OP_GETDEVLIST	48
+#define	NFSV4OP_LAYOUTCOMMIT	49
+#define	NFSV4OP_LAYOUTGET	50
+#define	NFSV4OP_LAYOUTRETURN	51
+#define	NFSV4OP_SECINFONONAME	52
+#define	NFSV4OP_SEQUENCE	53
+#define	NFSV4OP_SETSSV		54
+#define	NFSV4OP_TESTSTATEID	55
+#define	NFSV4OP_WANTDELEG	56
+#define	NFSV4OP_DESTROYCLIENTID	57
+#define	NFSV4OP_RECLAIMCOMPL	58
+
+/*
+ * Must be one more than last op#.
+ * NFSv4.2 isn't implemented yet, but define the op# limit for it.
+ */
+#define	NFSV41_NOPS		59
+#define	NFSV42_NOPS		72
+
+/* Quirky case if the illegal op code */
+#define	NFSV4OP_OPILLEGAL	10044
+
+/*
+ * Fake NFSV4OP_xxx used for nfsstat. Start at NFSV42_NOPS.
+ */
+#define	NFSV4OP_SYMLINK		(NFSV42_NOPS)
+#define	NFSV4OP_MKDIR		(NFSV42_NOPS + 1)
+#define	NFSV4OP_RMDIR		(NFSV42_NOPS + 2)
+#define	NFSV4OP_READDIRPLUS	(NFSV42_NOPS + 3)
+#define	NFSV4OP_MKNOD		(NFSV42_NOPS + 4)
+#define	NFSV4OP_FSSTAT		(NFSV42_NOPS + 5)
+#define	NFSV4OP_FSINFO		(NFSV42_NOPS + 6)
+#define	NFSV4OP_PATHCONF	(NFSV42_NOPS + 7)
+#define	NFSV4OP_V3CREATE	(NFSV42_NOPS + 8)
+
+/*
+ * This is the count of the fake operations listed above.
+ */
+#define	NFSV4OP_FAKENOPS	9
+
+/*
+ * and the Callback OPs
+ */
+#define	NFSV4OP_CBGETATTR	3
+#define	NFSV4OP_CBRECALL	4
+
+/*
+ * Must be one greater than the last Callback Operation# for NFSv4.0.
+ */
+#define	NFSV4OP_CBNOPS		5
+
+/*
+ * Additional Callback Ops for NFSv4.1 only.
+ */
+#define	NFSV4OP_CBLAYOUTRECALL	5
+#define	NFSV4OP_CBNOTIFY	6
+#define	NFSV4OP_CBPUSHDELEG	7
+#define	NFSV4OP_CBRECALLANY	8
+#define	NFSV4OP_CBRECALLOBJAVAIL 9
+#define	NFSV4OP_CBRECALLSLOT	10
+#define	NFSV4OP_CBSEQUENCE	11
+#define	NFSV4OP_CBWANTCANCELLED	12
+#define	NFSV4OP_CBNOTIFYLOCK	13
+#define	NFSV4OP_CBNOTIFYDEVID	14
+
+#define	NFSV41_CBNOPS		15
+#define	NFSV42_CBNOPS		16
+
+/*
+ * The lower numbers -> 21 are used by NFSv2 and v3. These define higher
+ * numbers used by NFSv4.
+ * NFS_V3NPROCS is one greater than the last V3 op and NFS_NPROCS is
+ * one greater than the last number.
+ */
+#ifndef	NFS_V3NPROCS
+#define	NFS_V3NPROCS		22
+
+#define	NFSPROC_LOOKUPP		22
+#define	NFSPROC_SETCLIENTID	23
+#define	NFSPROC_SETCLIENTIDCFRM	24
+#define	NFSPROC_LOCK		25
+#define	NFSPROC_LOCKU		26
+#define	NFSPROC_OPEN		27
+#define	NFSPROC_CLOSE		28
+#define	NFSPROC_OPENCONFIRM	29
+#define	NFSPROC_LOCKT		30
+#define	NFSPROC_OPENDOWNGRADE	31
+#define	NFSPROC_RENEW		32
+#define	NFSPROC_PUTROOTFH	33
+#define	NFSPROC_RELEASELCKOWN	34
+#define	NFSPROC_DELEGRETURN	35
+#define	NFSPROC_RETDELEGREMOVE	36
+#define	NFSPROC_RETDELEGRENAME1	37
+#define	NFSPROC_RETDELEGRENAME2	38
+#define	NFSPROC_GETACL		39
+#define	NFSPROC_SETACL		40
+
+/*
+ * Must be defined as one higher than the last Proc# above.
+ */
+#define	NFSV4_NPROCS		41
+
+/* Additional procedures for NFSv4.1. */
+#define	NFSPROC_EXCHANGEID	41
+#define	NFSPROC_CREATESESSION	42
+#define	NFSPROC_DESTROYSESSION	43
+#define	NFSPROC_DESTROYCLIENT	44
+#define	NFSPROC_FREESTATEID	45
+#define	NFSPROC_LAYOUTGET	46
+#define	NFSPROC_GETDEVICEINFO	47
+#define	NFSPROC_LAYOUTCOMMIT	48
+#define	NFSPROC_LAYOUTRETURN	49
+#define	NFSPROC_RECLAIMCOMPL	50
+#define	NFSPROC_WRITEDS		51
+#define	NFSPROC_READDS		52
+#define	NFSPROC_COMMITDS	53
+#define	NFSPROC_OPENLAYGET	54
+#define	NFSPROC_CREATELAYGET	55
+
+/*
+ * Must be defined as one higher than the last NFSv4.1 Proc# above.
+ */
+#define	NFSV41_NPROCS		56
+
+#endif	/* NFS_V3NPROCS */
+
+/*
+ * New stats structure.
+ * The vers field will be set to NFSSTATS_V1 by the caller.
+ */
+#define	NFSSTATS_V1	1
+struct nfsstatsv1 {
+	int		vers;	/* Set to version requested by caller. */
+	uint64_t	attrcache_hits;
+	uint64_t	attrcache_misses;
+	uint64_t	lookupcache_hits;
+	uint64_t	lookupcache_misses;
+	uint64_t	direofcache_hits;
+	uint64_t	direofcache_misses;
+	uint64_t	accesscache_hits;
+	uint64_t	accesscache_misses;
+	uint64_t	biocache_reads;
+	uint64_t	read_bios;
+	uint64_t	read_physios;
+	uint64_t	biocache_writes;
+	uint64_t	write_bios;
+	uint64_t	write_physios;
+	uint64_t	biocache_readlinks;
+	uint64_t	readlink_bios;
+	uint64_t	biocache_readdirs;
+	uint64_t	readdir_bios;
+	uint64_t	rpccnt[NFSV41_NPROCS + 13];
+	uint64_t	rpcretries;
+	uint64_t	srvrpccnt[NFSV42_NOPS + NFSV4OP_FAKENOPS];
+	uint64_t	srvrpc_errs;
+	uint64_t	srv_errs;
+	uint64_t	rpcrequests;
+	uint64_t	rpctimeouts;
+	uint64_t	rpcunexpected;
+	uint64_t	rpcinvalid;
+	uint64_t	srvcache_inproghits;
+	uint64_t	srvcache_idemdonehits;
+	uint64_t	srvcache_nonidemdonehits;
+	uint64_t	srvcache_misses;
+	uint64_t	srvcache_tcppeak;
+	int		srvcache_size;	/* Updated by atomic_xx_int(). */
+	uint64_t	srvclients;
+	uint64_t	srvopenowners;
+	uint64_t	srvopens;
+	uint64_t	srvlockowners;
+	uint64_t	srvlocks;
+	uint64_t	srvdelegates;
+	uint64_t	cbrpccnt[NFSV42_CBNOPS];
+	uint64_t	clopenowners;
+	uint64_t	clopens;
+	uint64_t	cllockowners;
+	uint64_t	cllocks;
+	uint64_t	cldelegates;
+	uint64_t	cllocalopenowners;
+	uint64_t	cllocalopens;
+	uint64_t	cllocallockowners;
+	uint64_t	cllocallocks;
+	uint64_t	srvstartcnt;
+	uint64_t	srvdonecnt;
+	uint64_t	srvbytes[NFSV42_NOPS + NFSV4OP_FAKENOPS];
+	uint64_t	srvops[NFSV42_NOPS + NFSV4OP_FAKENOPS];
+	struct bintime	srvduration[NFSV42_NOPS + NFSV4OP_FAKENOPS];
+	struct bintime	busyfrom;
+	struct bintime	busytime;
+};
+
+/*
+ * Old stats structure.
+ */
+struct ext_nfsstats {
+	int	attrcache_hits;
+	int	attrcache_misses;
+	int	lookupcache_hits;
+	int	lookupcache_misses;
+	int	direofcache_hits;
+	int	direofcache_misses;
+	int	accesscache_hits;
+	int	accesscache_misses;
+	int	biocache_reads;
+	int	read_bios;
+	int	read_physios;
+	int	biocache_writes;
+	int	write_bios;
+	int	write_physios;
+	int	biocache_readlinks;
+	int	readlink_bios;
+	int	biocache_readdirs;
+	int	readdir_bios;
+	int	rpccnt[NFSV4_NPROCS];
+	int	rpcretries;
+	int	srvrpccnt[NFSV4OP_NOPS + NFSV4OP_FAKENOPS];
+	int	srvrpc_errs;
+	int	srv_errs;
+	int	rpcrequests;
+	int	rpctimeouts;
+	int	rpcunexpected;
+	int	rpcinvalid;
+	int	srvcache_inproghits;
+	int	srvcache_idemdonehits;
+	int	srvcache_nonidemdonehits;
+	int	srvcache_misses;
+	int	srvcache_tcppeak;
+	int	srvcache_size;
+	int	srvclients;
+	int	srvopenowners;
+	int	srvopens;
+	int	srvlockowners;
+	int	srvlocks;
+	int	srvdelegates;
+	int	cbrpccnt[NFSV4OP_CBNOPS];
+	int	clopenowners;
+	int	clopens;
+	int	cllockowners;
+	int	cllocks;
+	int	cldelegates;
+	int	cllocalopenowners;
+	int	cllocalopens;
+	int	cllocallockowners;
+	int	cllocallocks;
+};
+
+#ifdef _KERNEL
+/*
+ * Define NFS_NPROCS as NFSV4_NPROCS for the experimental kernel code.
+ */
+#ifndef	NFS_NPROCS
+#define	NFS_NPROCS		NFSV4_NPROCS
+#endif
+
+#include <fs/nfs/nfskpiport.h>
+#include <fs/nfs/nfsdport.h>
+#include <fs/nfs/rpcv2.h>
+#include <fs/nfs/nfsproto.h>
+#include <fs/nfs/nfs.h>
+#include <fs/nfs/nfsclstate.h>
+#include <fs/nfs/nfs_var.h>
+#include <fs/nfs/nfsm_subs.h>
+#include <fs/nfs/nfsrvcache.h>
+#include <fs/nfs/nfsrvstate.h>
+#include <fs/nfs/xdr_subs.h>
+#include <fs/nfs/nfscl.h>
+#include <nfsclient/nfsargs.h>
+#include <fs/nfsclient/nfsmount.h>
+
+/*
+ * Just to keep nfs_var.h happy.
+ */
+struct nfs_vattr {
+	int	junk;
+};
+
+struct nfsvattr {
+	struct vattr	na_vattr;
+	nfsattrbit_t	na_suppattr;
+	u_int64_t	na_mntonfileno;
+	u_int64_t	na_filesid[2];
+};
+
+#define	na_type		na_vattr.va_type
+#define	na_mode		na_vattr.va_mode
+#define	na_nlink	na_vattr.va_nlink
+#define	na_uid		na_vattr.va_uid
+#define	na_gid		na_vattr.va_gid
+#define	na_fsid		na_vattr.va_fsid
+#define	na_fileid	na_vattr.va_fileid
+#define	na_size		na_vattr.va_size
+#define	na_blocksize	na_vattr.va_blocksize
+#define	na_atime	na_vattr.va_atime
+#define	na_mtime	na_vattr.va_mtime
+#define	na_ctime	na_vattr.va_ctime
+#define	na_gen		na_vattr.va_gen
+#define	na_flags	na_vattr.va_flags
+#define	na_rdev		na_vattr.va_rdev
+#define	na_bytes	na_vattr.va_bytes
+#define	na_filerev	na_vattr.va_filerev
+#define	na_vaflags	na_vattr.va_vaflags
+
+#include <fs/nfsclient/nfsnode.h>
+
+/*
+ * This is the header structure used for the lists, etc. (It has the
+ * above record in it.
+ */
+struct nfsrv_stablefirst {
+	LIST_HEAD(, nfsrv_stable) nsf_head;	/* Head of nfsrv_stable list */
+	time_t		nsf_eograce;	/* Time grace period ends */
+	time_t		*nsf_bootvals;	/* Previous boottime values */
+	struct file	*nsf_fp;	/* File table pointer */
+	u_char		nsf_flags;	/* NFSNSF_ flags */
+	struct nfsf_rec	nsf_rec;	/* and above first record */
+};
+#define	nsf_lease	nsf_rec.lease
+#define	nsf_numboots	nsf_rec.numboots
+
+/* NFSNSF_xxx flags */
+#define	NFSNSF_UPDATEDONE	0x01
+#define	NFSNSF_GRACEOVER	0x02
+#define	NFSNSF_NEEDLOCK		0x04
+#define	NFSNSF_EXPIREDCLIENT	0x08
+#define	NFSNSF_NOOPENS		0x10
+#define	NFSNSF_OK		0x20
+
+/*
+ * Maximum number of boot times allowed in record. Although there is
+ * really no need for a fixed upper bound, this serves as a sanity check
+ * for a corrupted file.
+ */
+#define	NFSNSF_MAXNUMBOOTS	10000
+
+/*
+ * This structure defines the other records in the file. The
+ * nst_client array is actually the size of the client string name.
+ */
+struct nfst_rec {
+	u_int16_t	len;
+	u_char		flag;
+	u_char		client[1];
+};
+/* and the values for flag */
+#define	NFSNST_NEWSTATE	0x1
+#define	NFSNST_REVOKE		0x2
+#define	NFSNST_GOTSTATE		0x4
+#define	NFSNST_RECLAIMED	0x8
+
+/*
+ * This structure is linked onto nfsrv_stablefirst for the duration of
+ * reclaim.
+ */
+struct nfsrv_stable {
+	LIST_ENTRY(nfsrv_stable) nst_list;
+	struct nfsclient	*nst_clp;
+	struct nfst_rec		nst_rec;
+};
+#define	nst_timestamp	nst_rec.timestamp
+#define	nst_len		nst_rec.len
+#define	nst_flag	nst_rec.flag
+#define	nst_client	nst_rec.client
+
+/*
+ * At some point the server will run out of kernel storage for
+ * state structures. For FreeBSD5.2, this results in a panic
+ * kmem_map is full. It happens at well over 1000000 opens plus
+ * locks on a PIII-800 with 256Mbytes, so that is where I've set
+ * the limit. If your server panics due to too many opens/locks,
+ * decrease the size of NFSRV_V4STATELIMIT. If you find the server
+ * returning NFS4ERR_RESOURCE a lot and have lots of memory, try
+ * increasing it.
+ */
+#define	NFSRV_V4STATELIMIT	500000	/* Max # of Opens + Locks */
+
+/*
+ * The type required differs with BSDen (just the second arg).
+ */
+void nfsrvd_rcv(struct socket *, void *, int);
+
+/*
+ * Macros for handling socket addresses. (Hopefully this makes the code
+ * more portable, since I've noticed some 'BSD don't have sockaddrs in
+ * mbufs any more.)
+ */
+#define	NFSSOCKADDR(a, t)	((t)(a))
+#define	NFSSOCKADDRSIZE(a, s)		((a)->sa_len = (s))
+
+/*
+ * These should be defined as a process or thread structure, as required
+ * for signal handling, etc.
+ */
+#define	NFSNEWCRED(c)		(crdup(c))
+#define	NFSPROCCRED(p)		((p)->td_ucred)
+#define	NFSFREECRED(c)		(crfree(c))
+#define	NFSUIOPROC(u, p)	((u)->uio_td = NULL)
+#define	NFSPROCP(p)		((p)->td_proc)
+
+/*
+ * Define these so that cn_hash and its length is ignored.
+ */
+#define	NFSCNHASHZERO(c)
+#define	NFSCNHASH(c, v)
+#define	NCHNAMLEN	9999999
+
+/*
+ * These macros are defined to initialize and set the timer routine.
+ */
+#define	NFS_TIMERINIT \
+	newnfs_timer(NULL)
+
+/*
+ * Handle SMP stuff:
+ */
+#define	NFSSTATESPINLOCK	extern struct mtx nfs_state_mutex
+#define	NFSLOCKSTATE()		mtx_lock(&nfs_state_mutex)
+#define	NFSUNLOCKSTATE()	mtx_unlock(&nfs_state_mutex)
+#define	NFSSTATEMUTEXPTR	(&nfs_state_mutex)
+#define	NFSREQSPINLOCK		extern struct mtx nfs_req_mutex
+#define	NFSLOCKREQ()		mtx_lock(&nfs_req_mutex)
+#define	NFSUNLOCKREQ()		mtx_unlock(&nfs_req_mutex)
+#define	NFSSOCKMUTEX		extern struct mtx nfs_slock_mutex
+#define	NFSSOCKMUTEXPTR		(&nfs_slock_mutex)
+#define	NFSLOCKSOCK()		mtx_lock(&nfs_slock_mutex)
+#define	NFSUNLOCKSOCK()		mtx_unlock(&nfs_slock_mutex)
+#define	NFSNAMEIDMUTEX		extern struct mtx nfs_nameid_mutex
+#define	NFSNAMEIDMUTEXPTR	(&nfs_nameid_mutex)
+#define	NFSLOCKNAMEID()		mtx_lock(&nfs_nameid_mutex)
+#define	NFSUNLOCKNAMEID()	mtx_unlock(&nfs_nameid_mutex)
+#define	NFSNAMEIDREQUIRED()	mtx_assert(&nfs_nameid_mutex, MA_OWNED)
+#define	NFSCLSTATEMUTEX		extern struct mtx nfs_clstate_mutex
+#define	NFSCLSTATEMUTEXPTR	(&nfs_clstate_mutex)
+#define	NFSLOCKCLSTATE()	mtx_lock(&nfs_clstate_mutex)
+#define	NFSUNLOCKCLSTATE()	mtx_unlock(&nfs_clstate_mutex)
+#define	NFSDLOCKMUTEX		extern struct mtx newnfsd_mtx
+#define	NFSDLOCKMUTEXPTR	(&newnfsd_mtx)
+#define	NFSD_LOCK()		mtx_lock(&newnfsd_mtx)
+#define	NFSD_UNLOCK()		mtx_unlock(&newnfsd_mtx)
+#define	NFSD_LOCK_ASSERT()	mtx_assert(&newnfsd_mtx, MA_OWNED)
+#define	NFSD_UNLOCK_ASSERT()	mtx_assert(&newnfsd_mtx, MA_NOTOWNED)
+#define	NFSV4ROOTLOCKMUTEX	extern struct mtx nfs_v4root_mutex
+#define	NFSV4ROOTLOCKMUTEXPTR	(&nfs_v4root_mutex)
+#define	NFSLOCKV4ROOTMUTEX()	mtx_lock(&nfs_v4root_mutex)
+#define	NFSUNLOCKV4ROOTMUTEX()	mtx_unlock(&nfs_v4root_mutex)
+#define	NFSLOCKNODE(n)		mtx_lock(&((n)->n_mtx))
+#define	NFSUNLOCKNODE(n)	mtx_unlock(&((n)->n_mtx))
+#define	NFSASSERTNODE(n)	mtx_assert(&((n)->n_mtx), MA_OWNED)
+#define	NFSLOCKMNT(m)		mtx_lock(&((m)->nm_mtx))
+#define	NFSUNLOCKMNT(m)		mtx_unlock(&((m)->nm_mtx))
+#define	NFSLOCKIOD()		mtx_lock(&ncl_iod_mutex)
+#define	NFSUNLOCKIOD()		mtx_unlock(&ncl_iod_mutex)
+#define	NFSASSERTIOD()		mtx_assert(&ncl_iod_mutex, MA_OWNED)
+#define	NFSLOCKREQUEST(r)	mtx_lock(&((r)->r_mtx))
+#define	NFSUNLOCKREQUEST(r)	mtx_unlock(&((r)->r_mtx))
+#define	NFSPROCLISTLOCK()	sx_slock(&allproc_lock)
+#define	NFSPROCLISTUNLOCK()	sx_sunlock(&allproc_lock)
+#define	NFSLOCKSOCKREQ(r)	mtx_lock(&((r)->nr_mtx))
+#define	NFSUNLOCKSOCKREQ(r)	mtx_unlock(&((r)->nr_mtx))
+#define	NFSLOCKDS(d)		mtx_lock(&((d)->nfsclds_mtx))
+#define	NFSUNLOCKDS(d)		mtx_unlock(&((d)->nfsclds_mtx))
+#define	NFSSESSIONMUTEXPTR(s)	(&((s)->mtx))
+#define	NFSLOCKSESSION(s)	mtx_lock(&((s)->mtx))
+#define	NFSUNLOCKSESSION(s)	mtx_unlock(&((s)->mtx))
+#define	NFSLAYOUTMUTEXPTR(l)	(&((l)->mtx))
+#define	NFSLOCKLAYOUT(l)	mtx_lock(&((l)->mtx))
+#define	NFSUNLOCKLAYOUT(l)	mtx_unlock(&((l)->mtx))
+#define	NFSDDSMUTEXPTR		(&nfsrv_dslock_mtx)
+#define	NFSDDSLOCK()		mtx_lock(&nfsrv_dslock_mtx)
+#define	NFSDDSUNLOCK()		mtx_unlock(&nfsrv_dslock_mtx)
+#define	NFSDDONTLISTMUTEXPTR	(&nfsrv_dontlistlock_mtx)
+#define	NFSDDONTLISTLOCK()	mtx_lock(&nfsrv_dontlistlock_mtx)
+#define	NFSDDONTLISTUNLOCK()	mtx_unlock(&nfsrv_dontlistlock_mtx)
+#define	NFSDRECALLMUTEXPTR	(&nfsrv_recalllock_mtx)
+#define	NFSDRECALLLOCK()	mtx_lock(&nfsrv_recalllock_mtx)
+#define	NFSDRECALLUNLOCK()	mtx_unlock(&nfsrv_recalllock_mtx)
+
+/*
+ * Use these macros to initialize/free a mutex.
+ */
+#define	NFSINITSOCKMUTEX(m)	mtx_init((m), "nfssock", NULL, MTX_DEF)
+#define	NFSFREEMUTEX(m)		mtx_destroy((m))
+
+int nfsmsleep(void *, void *, int, const char *, struct timespec *);
+
+/*
+ * And weird vm stuff in the nfs server.
+ */
+#define	PDIRUNLOCK	0x0
+#define	MAX_COMMIT_COUNT	(1024 * 1024)
+
+/*
+ * Define these to handle the type of va_rdev.
+ */
+#define	NFSMAKEDEV(m, n)	makedev((m), (n))
+#define	NFSMAJOR(d)		major(d)
+#define	NFSMINOR(d)		minor(d)
+
+/*
+ * The vnode tag for nfsv4root.
+ */
+#define	VT_NFSV4ROOT		"nfsv4root"
+
+/*
+ * Define whatever it takes to do a vn_rdwr().
+ */
+#define	NFSD_RDWR(r, v, b, l, o, s, i, c, a, p) \
+	vn_rdwr((r), (v), (b), (l), (o), (s), (i), (c), NULL, (a), (p))
+
+/*
+ * Macros for handling memory for different BSDen.
+ * NFSBCOPY(src, dst, len) - copies len bytes, non-overlapping
+ * NFSOVBCOPY(src, dst, len) - ditto, but data areas might overlap
+ * NFSBCMP(cp1, cp2, len) - compare len bytes, return 0 if same
+ * NFSBZERO(cp, len) - set len bytes to 0x0
+ */
+#define	NFSBCOPY(s, d, l)	bcopy((s), (d), (l))
+#define	NFSOVBCOPY(s, d, l)	ovbcopy((s), (d), (l))
+#define	NFSBCMP(s, d, l)	bcmp((s), (d), (l))
+#define	NFSBZERO(s, l)		bzero((s), (l))
+
+/*
+ * Some queue.h files don't have these dfined in them.
+ */
+#define	LIST_END(head)		NULL
+#define	SLIST_END(head)		NULL
+#define	TAILQ_END(head)		NULL
+
+/*
+ * This must be defined to be a global variable that increments once
+ * per second, but never stops or goes backwards, even when a "date"
+ * command changes the TOD clock. It is used for delta times for
+ * leases, etc.
+ */
+#define	NFSD_MONOSEC		time_uptime
+
+/*
+ * Declare the malloc types.
+ */
+MALLOC_DECLARE(M_NEWNFSRVCACHE);
+MALLOC_DECLARE(M_NEWNFSDCLIENT);
+MALLOC_DECLARE(M_NEWNFSDSTATE);
+MALLOC_DECLARE(M_NEWNFSDLOCK);
+MALLOC_DECLARE(M_NEWNFSDLOCKFILE);
+MALLOC_DECLARE(M_NEWNFSSTRING);
+MALLOC_DECLARE(M_NEWNFSUSERGROUP);
+MALLOC_DECLARE(M_NEWNFSDREQ);
+MALLOC_DECLARE(M_NEWNFSFH);
+MALLOC_DECLARE(M_NEWNFSCLOWNER);
+MALLOC_DECLARE(M_NEWNFSCLOPEN);
+MALLOC_DECLARE(M_NEWNFSCLDELEG);
+MALLOC_DECLARE(M_NEWNFSCLCLIENT);
+MALLOC_DECLARE(M_NEWNFSCLLOCKOWNER);
+MALLOC_DECLARE(M_NEWNFSCLLOCK);
+MALLOC_DECLARE(M_NEWNFSDIROFF);
+MALLOC_DECLARE(M_NEWNFSV4NODE);
+MALLOC_DECLARE(M_NEWNFSDIRECTIO);
+MALLOC_DECLARE(M_NEWNFSMNT);
+MALLOC_DECLARE(M_NEWNFSDROLLBACK);
+MALLOC_DECLARE(M_NEWNFSLAYOUT);
+MALLOC_DECLARE(M_NEWNFSFLAYOUT);
+MALLOC_DECLARE(M_NEWNFSDEVINFO);
+MALLOC_DECLARE(M_NEWNFSSOCKREQ);
+MALLOC_DECLARE(M_NEWNFSCLDS);
+MALLOC_DECLARE(M_NEWNFSLAYRECALL);
+MALLOC_DECLARE(M_NEWNFSDSESSION);
+#define	M_NFSRVCACHE	M_NEWNFSRVCACHE
+#define	M_NFSDCLIENT	M_NEWNFSDCLIENT
+#define	M_NFSDSTATE	M_NEWNFSDSTATE
+#define	M_NFSDLOCK	M_NEWNFSDLOCK
+#define	M_NFSDLOCKFILE	M_NEWNFSDLOCKFILE
+#define	M_NFSSTRING	M_NEWNFSSTRING
+#define	M_NFSUSERGROUP	M_NEWNFSUSERGROUP
+#define	M_NFSDREQ	M_NEWNFSDREQ
+#define	M_NFSFH		M_NEWNFSFH
+#define	M_NFSCLOWNER	M_NEWNFSCLOWNER
+#define	M_NFSCLOPEN	M_NEWNFSCLOPEN
+#define	M_NFSCLDELEG	M_NEWNFSCLDELEG
+#define	M_NFSCLCLIENT	M_NEWNFSCLCLIENT
+#define	M_NFSCLLOCKOWNER M_NEWNFSCLLOCKOWNER
+#define	M_NFSCLLOCK	M_NEWNFSCLLOCK
+#define	M_NFSDIROFF	M_NEWNFSDIROFF
+#define	M_NFSV4NODE	M_NEWNFSV4NODE
+#define	M_NFSDIRECTIO	M_NEWNFSDIRECTIO
+#define	M_NFSDROLLBACK	M_NEWNFSDROLLBACK
+#define	M_NFSLAYOUT	M_NEWNFSLAYOUT
+#define	M_NFSFLAYOUT	M_NEWNFSFLAYOUT
+#define	M_NFSDEVINFO	M_NEWNFSDEVINFO
+#define	M_NFSSOCKREQ	M_NEWNFSSOCKREQ
+#define	M_NFSCLDS	M_NEWNFSCLDS
+#define	M_NFSLAYRECALL	M_NEWNFSLAYRECALL
+#define	M_NFSDSESSION	M_NEWNFSDSESSION
+
+#define	NFSINT_SIGMASK(set) 						\
+	(SIGISMEMBER(set, SIGINT) || SIGISMEMBER(set, SIGTERM) ||	\
+	 SIGISMEMBER(set, SIGHUP) || SIGISMEMBER(set, SIGKILL) ||	\
+	 SIGISMEMBER(set, SIGQUIT))
+
+/*
+ * Convert a quota block count to byte count.
+ */
+#define	NFSQUOTABLKTOBYTE(q, b)	(q) *= (b)
+
+/*
+ * Define this as the largest file size supported. (It should probably
+ * be available via a VFS_xxx Op, but it isn't.
+ */
+#define	NFSRV_MAXFILESIZE	((u_int64_t)0x800000000000)
+
+/*
+ * Set this macro to index() or strchr(), whichever is supported.
+ */
+#define	STRCHR(s, c)		strchr((s), (c))
+
+/*
+ * Set the n_time in the client write rpc, as required.
+ */
+#define	NFSWRITERPC_SETTIME(w, n, a, v4)				\
+	do {								\
+		if (w) {						\
+			NFSLOCKNODE(n);					\
+			(n)->n_mtime = (a)->na_mtime;			\
+			if (v4)						\
+				(n)->n_change = (a)->na_filerev;	\
+			NFSUNLOCKNODE(n);				\
+		}							\
+	} while (0)
+
+/*
+ * Fake value, just to make the client work.
+ */
+#define	NFS_LATTR_NOSHRINK	1
+
+/*
+ * Prototypes for functions where the arguments vary for different ports.
+ */
+int nfscl_loadattrcache(struct vnode **, struct nfsvattr *, void *, void *,
+    int, int);
+int newnfs_realign(struct mbuf **, int);
+bool ncl_pager_setsize(struct vnode *vp, u_quad_t *nsizep);
+
+/*
+ * If the port runs on an SMP box that can enforce Atomic ops with low
+ * overheads, define these as atomic increments/decrements. If not,
+ * don't worry about it, since these are used for stats that can be
+ * "out by one" without disastrous consequences.
+ */
+#define	NFSINCRGLOBAL(a)	((a)++)
+
+/*
+ * Assorted funky stuff to make things work under Darwin8.
+ */
+/*
+ * These macros checks for a field in vattr being set.
+ */
+#define	NFSATTRISSET(t, v, a)	((v)->a != (t)VNOVAL)
+#define	NFSATTRISSETTIME(v, a)	((v)->a.tv_sec != VNOVAL)
+
+/*
+ * Manipulate mount flags.
+ */
+#define	NFSSTA_HASWRITEVERF	0x00040000  /* Has write verifier */
+#define	NFSSTA_GOTFSINFO	0x00100000  /* Got the fsinfo */
+#define	NFSSTA_OPENMODE		0x00200000  /* Must use correct open mode */
+#define	NFSSTA_FLEXFILE		0x00800000  /* Use Flex File Layout */
+#define	NFSSTA_NOLAYOUTCOMMIT	0x04000000  /* Don't do LayoutCommit */
+#define	NFSSTA_SESSPERSIST	0x08000000  /* Has a persistent session */
+#define	NFSSTA_TIMEO		0x10000000  /* Experiencing a timeout */
+#define	NFSSTA_LOCKTIMEO	0x20000000  /* Experiencing a lockd timeout */
+#define	NFSSTA_HASSETFSID	0x40000000  /* Has set the fsid */
+#define	NFSSTA_PNFS		0x80000000  /* pNFS is enabled */
+
+#define	NFSHASNFSV3(n)		((n)->nm_flag & NFSMNT_NFSV3)
+#define	NFSHASNFSV4(n)		((n)->nm_flag & NFSMNT_NFSV4)
+#define	NFSHASNFSV4N(n)		((n)->nm_minorvers > 0)
+#define	NFSHASNFSV3OR4(n)	((n)->nm_flag & (NFSMNT_NFSV3 | NFSMNT_NFSV4))
+#define	NFSHASGOTFSINFO(n)	((n)->nm_state & NFSSTA_GOTFSINFO)
+#define	NFSHASHASSETFSID(n)	((n)->nm_state & NFSSTA_HASSETFSID)
+#define	NFSHASSTRICT3530(n)	((n)->nm_flag & NFSMNT_STRICT3530)
+#define	NFSHASWRITEVERF(n)	((n)->nm_state & NFSSTA_HASWRITEVERF)
+#define	NFSHASINT(n)		((n)->nm_flag & NFSMNT_INT)
+#define	NFSHASSOFT(n)		((n)->nm_flag & NFSMNT_SOFT)
+#define	NFSHASINTORSOFT(n)	((n)->nm_flag & (NFSMNT_INT | NFSMNT_SOFT))
+#define	NFSHASDUMBTIMR(n)	((n)->nm_flag & NFSMNT_DUMBTIMR)
+#define	NFSHASNOCONN(n)		((n)->nm_flag & NFSMNT_MNTD)
+#define	NFSHASKERB(n)		((n)->nm_flag & NFSMNT_KERB)
+#define	NFSHASALLGSSNAME(n)	((n)->nm_flag & NFSMNT_ALLGSSNAME)
+#define	NFSHASINTEGRITY(n)	((n)->nm_flag & NFSMNT_INTEGRITY)
+#define	NFSHASPRIVACY(n)	((n)->nm_flag & NFSMNT_PRIVACY)
+#define	NFSSETWRITEVERF(n)	((n)->nm_state |= NFSSTA_HASWRITEVERF)
+#define	NFSSETHASSETFSID(n)	((n)->nm_state |= NFSSTA_HASSETFSID)
+#define	NFSHASPNFSOPT(n)	((n)->nm_flag & NFSMNT_PNFS)
+#define	NFSHASNOLAYOUTCOMMIT(n)	((n)->nm_state & NFSSTA_NOLAYOUTCOMMIT)
+#define	NFSHASSESSPERSIST(n)	((n)->nm_state & NFSSTA_SESSPERSIST)
+#define	NFSHASPNFS(n)		((n)->nm_state & NFSSTA_PNFS)
+#define	NFSHASFLEXFILE(n)	((n)->nm_state & NFSSTA_FLEXFILE)
+#define	NFSHASOPENMODE(n)	((n)->nm_state & NFSSTA_OPENMODE)
+#define	NFSHASONEOPENOWN(n)	(((n)->nm_flag & NFSMNT_ONEOPENOWN) != 0 &&	\
+				    (n)->nm_minorvers > 0)
+
+/*
+ * Gets the stats field out of the mount structure.
+ */
+#define	vfs_statfs(m)	(&((m)->mnt_stat))
+
+/*
+ * Set boottime.
+ */
+#define	NFSSETBOOTTIME(b)	(getboottime(&b))
+
+/*
+ * The size of directory blocks in the buffer cache.
+ * MUST BE in the range of PAGE_SIZE <= NFS_DIRBLKSIZ <= MAXBSIZE!!
+ */
+#define	NFS_DIRBLKSIZ	(16 * DIRBLKSIZ) /* Must be a multiple of DIRBLKSIZ */
+
+/*
+ * Define these macros to access mnt_flag fields.
+ */
+#define	NFSMNT_RDONLY(m)	((m)->mnt_flag & MNT_RDONLY)
+#endif	/* _KERNEL */
+
+/*
+ * Define a structure similar to ufs_args for use in exporting the V4 root.
+ */
+struct nfsex_args {
+	char	*fspec;
+	struct export_args	export;
+};
+
+/*
+ * These export flags should be defined, but there are no bits left.
+ * Maybe a separate mnt_exflag field could be added or the mnt_flag
+ * field increased to 64 bits?
+ */
+#ifndef	MNT_EXSTRICTACCESS
+#define	MNT_EXSTRICTACCESS	0x0
+#endif
+#ifndef MNT_EXV4ONLY
+#define	MNT_EXV4ONLY		0x0
+#endif
+
+#ifdef _KERNEL
+/*
+ * Define this to invalidate the attribute cache for the nfs node.
+ */
+#define	NFSINVALATTRCACHE(n)	((n)->n_attrstamp = 0)
+
+/* Used for FreeBSD only */
+void nfsd_mntinit(void);
+
+/*
+ * Define these for vnode lock/unlock ops.
+ *
+ * These are good abstractions to macro out, so that they can be added to
+ * later, for debugging or stats, etc.
+ */
+#define	NFSVOPLOCK(v, f)	vn_lock((v), (f))
+#define	NFSVOPUNLOCK(v, f)	VOP_UNLOCK((v), (f))
+#define	NFSVOPISLOCKED(v)	VOP_ISLOCKED((v))
+
+/*
+ * Define ncl_hash().
+ */
+#define	ncl_hash(f, l)	(fnv_32_buf((f), (l), FNV1_32_INIT))
+
+int newnfs_iosize(struct nfsmount *);
+
+int newnfs_vncmpf(struct vnode *, void *);
+
+#ifndef NFS_MINDIRATTRTIMO
+#define	NFS_MINDIRATTRTIMO 3		/* VDIR attrib cache timeout in sec */
+#endif
+#ifndef NFS_MAXDIRATTRTIMO
+#define	NFS_MAXDIRATTRTIMO 60
+#endif
+
+/*
+ * Nfs outstanding request list element
+ */
+struct nfsreq {
+	TAILQ_ENTRY(nfsreq) r_chain;
+	u_int32_t	r_flags;	/* flags on request, see below */
+	struct nfsmount *r_nmp;		/* Client mnt ptr */
+	struct mtx	r_mtx;		/* Mutex lock for this structure */
+};
+
+#ifndef NFS_MAXBSIZE
+#define	NFS_MAXBSIZE	(maxbcachebuf)
+#endif
+
+/*
+ * This macro checks to see if issuing of delegations is allowed for this
+ * vnode.
+ */
+#ifdef VV_DISABLEDELEG
+#define	NFSVNO_DELEGOK(v)						\
+	((v) == NULL || ((v)->v_vflag & VV_DISABLEDELEG) == 0)
+#else
+#define	NFSVNO_DELEGOK(v)	(1)
+#endif
+
+/*
+ * Name used by getnewvnode() to describe filesystem, "nfs".
+ * For performance reasons it is useful to have the same string
+ * used in both places that call getnewvnode().
+ */
+extern const char nfs_vnode_tag[];
+
+/*
+ * Check for the errors that indicate a DS should be disabled.
+ * ENXIO indicates that the krpc cannot do an RPC on the DS.
+ * EIO is returned by the RPC as an indication of I/O problems on the
+ * server.
+ * Are there other fatal errors?
+ */
+#define	nfsds_failerr(e)	((e) == ENXIO || (e) == EIO)
+
+/*
+ * Get a pointer to the MDS session, which is always the first element
+ * in the list.
+ * This macro can only be safely used when the NFSLOCKMNT() lock is held.
+ * The inline function can be used when the lock isn't held.
+ */
+#define	NFSMNT_MDSSESSION(m)	(&(TAILQ_FIRST(&((m)->nm_sess))->nfsclds_sess))
+
+static __inline struct nfsclsession *
+nfsmnt_mdssession(struct nfsmount *nmp)
+{
+	struct nfsclsession *tsep;
+
+	tsep = NULL;
+	mtx_lock(&nmp->nm_mtx);
+	if (TAILQ_FIRST(&nmp->nm_sess) != NULL)
+		tsep = NFSMNT_MDSSESSION(nmp);
+	mtx_unlock(&nmp->nm_mtx);
+	return (tsep);
+}
+
+#endif	/* _KERNEL */
+
+#endif	/* _NFS_NFSPORT_H */