xref: /dflybsd-src/sys/vfs/nfs/nfs_vfsops.c (revision c5541aee854b0d32586182b733a9ea4d4c92168b)
1 /*
2  * Copyright (c) 1989, 1993, 1995
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Rick Macklem at The University of Guelph.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)nfs_vfsops.c	8.12 (Berkeley) 5/20/95
37  * $FreeBSD: src/sys/nfs/nfs_vfsops.c,v 1.91.2.7 2003/01/27 20:04:08 dillon Exp $
38  * $DragonFly: src/sys/vfs/nfs/nfs_vfsops.c,v 1.15 2004/04/07 05:15:48 dillon Exp $
39  */
40 
41 #include "opt_bootp.h"
42 
43 #include <sys/param.h>
44 #include <sys/sockio.h>
45 #include <sys/proc.h>
46 #include <sys/vnode.h>
47 #include <sys/kernel.h>
48 #include <sys/sysctl.h>
49 #include <sys/malloc.h>
50 #include <sys/mount.h>
51 #include <sys/mbuf.h>
52 #include <sys/socket.h>
53 #include <sys/socketvar.h>
54 #include <sys/systm.h>
55 
56 #include <vm/vm.h>
57 #include <vm/vm_extern.h>
58 #include <vm/vm_zone.h>
59 
60 #include <net/if.h>
61 #include <net/route.h>
62 #include <netinet/in.h>
63 
64 #include "rpcv2.h"
65 #include "nfsproto.h"
66 #include "nfs.h"
67 #include "nfsmount.h"
68 #include "nfsnode.h"
69 #include "xdr_subs.h"
70 #include "nfsm_subs.h"
71 #include "nfsdiskless.h"
72 #include "nqnfs.h"
73 
74 extern int	nfs_mountroot(struct mount *mp);
75 extern void	bootpc_init(void);
76 
77 extern int	nfs_ticks;
78 
79 MALLOC_DEFINE(M_NFSREQ, "NFS req", "NFS request header");
80 MALLOC_DEFINE(M_NFSBIGFH, "NFSV3 bigfh", "NFS version 3 file handle");
81 MALLOC_DEFINE(M_NFSD, "NFS daemon", "Nfs server daemon structure");
82 MALLOC_DEFINE(M_NFSDIROFF, "NFSV3 diroff", "NFS directory offset data");
83 MALLOC_DEFINE(M_NFSRVDESC, "NFSV3 srvdesc", "NFS server socket descriptor");
84 MALLOC_DEFINE(M_NFSUID, "NFS uid", "Nfs uid mapping structure");
85 MALLOC_DEFINE(M_NQLEASE, "NQNFS Lease", "Nqnfs lease");
86 MALLOC_DEFINE(M_NFSHASH, "NFS hash", "NFS hash tables");
87 
88 vm_zone_t nfsmount_zone;
89 
90 struct nfsstats	nfsstats;
91 SYSCTL_NODE(_vfs, OID_AUTO, nfs, CTLFLAG_RW, 0, "NFS filesystem");
92 SYSCTL_STRUCT(_vfs_nfs, NFS_NFSSTATS, nfsstats, CTLFLAG_RD,
93 	&nfsstats, nfsstats, "");
94 static int nfs_ip_paranoia = 1;
95 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_ip_paranoia, CTLFLAG_RW,
96 	&nfs_ip_paranoia, 0, "");
97 #ifdef NFS_DEBUG
98 int nfs_debug;
99 SYSCTL_INT(_vfs_nfs, OID_AUTO, debug, CTLFLAG_RW, &nfs_debug, 0, "");
100 #endif
101 
102 /*
103  * Tunable to determine the Read/Write unit size.  Maximum value
104  * is NFS_MAXDATA.  We also default to NFS_MAXDATA.
105  */
106 static int nfs_io_size = NFS_MAXDATA;
107 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_io_size, CTLFLAG_RW,
108 	&nfs_io_size, 0, "NFS optimal I/O unit size");
109 
110 static void	nfs_decode_args (struct nfsmount *nmp,
111 			struct nfs_args *argp);
112 static int	mountnfs (struct nfs_args *,struct mount *,
113 			struct sockaddr *,char *,char *,struct vnode **);
114 static int	nfs_mount ( struct mount *mp, char *path, caddr_t data,
115 			struct nameidata *ndp, struct thread *td);
116 static int	nfs_unmount ( struct mount *mp, int mntflags,
117 			struct thread *td);
118 static int	nfs_root ( struct mount *mp, struct vnode **vpp);
119 static int	nfs_statfs ( struct mount *mp, struct statfs *sbp,
120 			struct thread *td);
121 static int	nfs_sync ( struct mount *mp, int waitfor,
122 			struct thread *td);
123 
124 /*
125  * nfs vfs operations.
126  */
127 static struct vfsops nfs_vfsops = {
128 	nfs_mount,
129 	vfs_stdstart,
130 	nfs_unmount,
131 	nfs_root,
132 	vfs_stdquotactl,
133 	nfs_statfs,
134 	nfs_sync,
135 	vfs_stdvget,
136 	vfs_stdfhtovp,		/* shouldn't happen */
137 	vfs_stdcheckexp,
138 	vfs_stdvptofh,		/* shouldn't happen */
139 	nfs_init,
140 	nfs_uninit,
141 	vfs_stdextattrctl,
142 };
143 VFS_SET(nfs_vfsops, nfs, VFCF_NETWORK);
144 
145 /*
146  * This structure must be filled in by a primary bootstrap or bootstrap
147  * server for a diskless/dataless machine. It is initialized below just
148  * to ensure that it is allocated to initialized data (.data not .bss).
149  */
150 struct nfs_diskless nfs_diskless = { { { 0 } } };
151 struct nfsv3_diskless nfsv3_diskless = { { { 0 } } };
152 int nfs_diskless_valid = 0;
153 
154 SYSCTL_INT(_vfs_nfs, OID_AUTO, diskless_valid, CTLFLAG_RD,
155 	&nfs_diskless_valid, 0, "");
156 
157 SYSCTL_STRING(_vfs_nfs, OID_AUTO, diskless_rootpath, CTLFLAG_RD,
158 	nfsv3_diskless.root_hostnam, 0, "");
159 
160 SYSCTL_OPAQUE(_vfs_nfs, OID_AUTO, diskless_rootaddr, CTLFLAG_RD,
161 	&nfsv3_diskless.root_saddr, sizeof nfsv3_diskless.root_saddr,
162 	"%Ssockaddr_in", "");
163 
164 SYSCTL_STRING(_vfs_nfs, OID_AUTO, diskless_swappath, CTLFLAG_RD,
165 	nfsv3_diskless.swap_hostnam, 0, "");
166 
167 SYSCTL_OPAQUE(_vfs_nfs, OID_AUTO, diskless_swapaddr, CTLFLAG_RD,
168 	&nfsv3_diskless.swap_saddr, sizeof nfsv3_diskless.swap_saddr,
169 	"%Ssockaddr_in","");
170 
171 
172 void nfsargs_ntoh (struct nfs_args *);
173 static int nfs_mountdiskless (char *, char *, int,
174 				  struct sockaddr_in *, struct nfs_args *,
175 				  struct thread *, struct vnode **,
176 				  struct mount **);
177 static void nfs_convert_diskless (void);
178 static void nfs_convert_oargs (struct nfs_args *args,
179 				   struct onfs_args *oargs);
180 
181 /*
182  * Calculate the buffer I/O block size to use.  The maximum V2 block size
183  * is typically 8K, the maximum datagram size is typically 16K, and the
184  * maximum V3 block size is typically 32K.  The buffer cache tends to work
185  * best with 16K blocks but we allow 32K for TCP connections.
186  *
187  * We force the block size to be at least a page for buffer cache efficiency.
188  */
189 static
190 int
191 nfs_iosize(int v3, int sotype)
192 {
193 	int iosize;
194 	int iomax;
195 
196 	if (v3) {
197 		if (sotype == SOCK_STREAM)
198 			iomax = NFS_MAXDATA;
199 		else
200 			iomax = NFS_MAXDGRAMDATA;
201 	} else {
202 		iomax = NFS_V2MAXDATA;
203 	}
204 	if ((iosize = nfs_io_size) > iomax)
205 		iosize = iomax;
206 	if (iosize < PAGE_SIZE)
207 		iosize = PAGE_SIZE;
208 	return iosize;
209 }
210 
211 static void
212 nfs_convert_oargs(args, oargs)
213 	struct nfs_args *args;
214 	struct onfs_args *oargs;
215 {
216 	args->version = NFS_ARGSVERSION;
217 	args->addr = oargs->addr;
218 	args->addrlen = oargs->addrlen;
219 	args->sotype = oargs->sotype;
220 	args->proto = oargs->proto;
221 	args->fh = oargs->fh;
222 	args->fhsize = oargs->fhsize;
223 	args->flags = oargs->flags;
224 	args->wsize = oargs->wsize;
225 	args->rsize = oargs->rsize;
226 	args->readdirsize = oargs->readdirsize;
227 	args->timeo = oargs->timeo;
228 	args->retrans = oargs->retrans;
229 	args->maxgrouplist = oargs->maxgrouplist;
230 	args->readahead = oargs->readahead;
231 	args->leaseterm = oargs->leaseterm;
232 	args->deadthresh = oargs->deadthresh;
233 	args->hostname = oargs->hostname;
234 }
235 
236 static void
237 nfs_convert_diskless()
238 {
239 	bcopy(&nfs_diskless.myif, &nfsv3_diskless.myif,
240 		sizeof(struct ifaliasreq));
241 	bcopy(&nfs_diskless.mygateway, &nfsv3_diskless.mygateway,
242 		sizeof(struct sockaddr_in));
243 	nfs_convert_oargs(&nfsv3_diskless.swap_args,&nfs_diskless.swap_args);
244 	nfsv3_diskless.swap_fhsize = NFSX_V2FH;
245 	bcopy(nfs_diskless.swap_fh,nfsv3_diskless.swap_fh,NFSX_V2FH);
246 	bcopy(&nfs_diskless.swap_saddr,&nfsv3_diskless.swap_saddr,
247 		sizeof(struct sockaddr_in));
248 	bcopy(nfs_diskless.swap_hostnam,nfsv3_diskless.swap_hostnam, MNAMELEN);
249 	nfsv3_diskless.swap_nblks = nfs_diskless.swap_nblks;
250 	bcopy(&nfs_diskless.swap_ucred, &nfsv3_diskless.swap_ucred,
251 		sizeof(struct ucred));
252 	nfs_convert_oargs(&nfsv3_diskless.root_args,&nfs_diskless.root_args);
253 	nfsv3_diskless.root_fhsize = NFSX_V2FH;
254 	bcopy(nfs_diskless.root_fh,nfsv3_diskless.root_fh,NFSX_V2FH);
255 	bcopy(&nfs_diskless.root_saddr,&nfsv3_diskless.root_saddr,
256 		sizeof(struct sockaddr_in));
257 	bcopy(nfs_diskless.root_hostnam,nfsv3_diskless.root_hostnam, MNAMELEN);
258 	nfsv3_diskless.root_time = nfs_diskless.root_time;
259 	bcopy(nfs_diskless.my_hostnam,nfsv3_diskless.my_hostnam,
260 		MAXHOSTNAMELEN);
261 	nfs_diskless_valid = 3;
262 }
263 
264 /*
265  * nfs statfs call
266  */
267 int
268 nfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td)
269 {
270 	struct vnode *vp;
271 	struct nfs_statfs *sfp;
272 	caddr_t cp;
273 	u_int32_t *tl;
274 	int32_t t1, t2;
275 	caddr_t bpos, dpos, cp2;
276 	struct nfsmount *nmp = VFSTONFS(mp);
277 	int error = 0, v3 = (nmp->nm_flag & NFSMNT_NFSV3), retattr;
278 	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
279 	struct ucred *cred;
280 	struct nfsnode *np;
281 	u_quad_t tquad;
282 
283 #ifndef nolint
284 	sfp = (struct nfs_statfs *)0;
285 #endif
286 	error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
287 	if (error)
288 		return (error);
289 	vp = NFSTOV(np);
290 	cred = crget();
291 	cred->cr_ngroups = 1;
292 	if (v3 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0)
293 		(void)nfs_fsinfo(nmp, vp, td);
294 	nfsstats.rpccnt[NFSPROC_FSSTAT]++;
295 	nfsm_reqhead(vp, NFSPROC_FSSTAT, NFSX_FH(v3));
296 	nfsm_fhtom(vp, v3);
297 	nfsm_request(vp, NFSPROC_FSSTAT, td, cred);
298 	if (v3)
299 		nfsm_postop_attr(vp, retattr);
300 	if (error) {
301 		if (mrep != NULL)
302 			m_freem(mrep);
303 		goto nfsmout;
304 	}
305 	nfsm_dissect(sfp, struct nfs_statfs *, NFSX_STATFS(v3));
306 	sbp->f_flags = nmp->nm_flag;
307 	sbp->f_iosize = nfs_iosize(v3, nmp->nm_sotype);
308 
309 	if (v3) {
310 		sbp->f_bsize = NFS_FABLKSIZE;
311 		tquad = fxdr_hyper(&sfp->sf_tbytes);
312 		sbp->f_blocks = (long)(tquad / ((u_quad_t)NFS_FABLKSIZE));
313 		tquad = fxdr_hyper(&sfp->sf_fbytes);
314 		sbp->f_bfree = (long)(tquad / ((u_quad_t)NFS_FABLKSIZE));
315 		tquad = fxdr_hyper(&sfp->sf_abytes);
316 		sbp->f_bavail = (long)(tquad / ((u_quad_t)NFS_FABLKSIZE));
317 		sbp->f_files = (fxdr_unsigned(int32_t,
318 		    sfp->sf_tfiles.nfsuquad[1]) & 0x7fffffff);
319 		sbp->f_ffree = (fxdr_unsigned(int32_t,
320 		    sfp->sf_ffiles.nfsuquad[1]) & 0x7fffffff);
321 	} else {
322 		sbp->f_bsize = fxdr_unsigned(int32_t, sfp->sf_bsize);
323 		sbp->f_blocks = fxdr_unsigned(int32_t, sfp->sf_blocks);
324 		sbp->f_bfree = fxdr_unsigned(int32_t, sfp->sf_bfree);
325 		sbp->f_bavail = fxdr_unsigned(int32_t, sfp->sf_bavail);
326 		sbp->f_files = 0;
327 		sbp->f_ffree = 0;
328 	}
329 	if (sbp != &mp->mnt_stat) {
330 		sbp->f_type = mp->mnt_vfc->vfc_typenum;
331 		bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
332 		bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
333 	}
334 	m_freem(mrep);
335 nfsmout:
336 	vput(vp);
337 	crfree(cred);
338 	return (error);
339 }
340 
341 /*
342  * nfs version 3 fsinfo rpc call
343  */
344 int
345 nfs_fsinfo(struct nfsmount *nmp, struct vnode *vp, struct thread *td)
346 {
347 	struct nfsv3_fsinfo *fsp;
348 	caddr_t cp;
349 	int32_t t1, t2;
350 	u_int32_t *tl, pref, max;
351 	caddr_t bpos, dpos, cp2;
352 	int error = 0, retattr;
353 	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
354 	u_int64_t maxfsize;
355 
356 	nfsstats.rpccnt[NFSPROC_FSINFO]++;
357 	nfsm_reqhead(vp, NFSPROC_FSINFO, NFSX_FH(1));
358 	nfsm_fhtom(vp, 1);
359 	nfsm_request(vp, NFSPROC_FSINFO, td, nfs_vpcred(vp, ND_READ));
360 	nfsm_postop_attr(vp, retattr);
361 	if (!error) {
362 		nfsm_dissect(fsp, struct nfsv3_fsinfo *, NFSX_V3FSINFO);
363 		pref = fxdr_unsigned(u_int32_t, fsp->fs_wtpref);
364 		if (pref < nmp->nm_wsize && pref >= NFS_FABLKSIZE)
365 			nmp->nm_wsize = (pref + NFS_FABLKSIZE - 1) &
366 				~(NFS_FABLKSIZE - 1);
367 		max = fxdr_unsigned(u_int32_t, fsp->fs_wtmax);
368 		if (max < nmp->nm_wsize && max > 0) {
369 			nmp->nm_wsize = max & ~(NFS_FABLKSIZE - 1);
370 			if (nmp->nm_wsize == 0)
371 				nmp->nm_wsize = max;
372 		}
373 		pref = fxdr_unsigned(u_int32_t, fsp->fs_rtpref);
374 		if (pref < nmp->nm_rsize && pref >= NFS_FABLKSIZE)
375 			nmp->nm_rsize = (pref + NFS_FABLKSIZE - 1) &
376 				~(NFS_FABLKSIZE - 1);
377 		max = fxdr_unsigned(u_int32_t, fsp->fs_rtmax);
378 		if (max < nmp->nm_rsize && max > 0) {
379 			nmp->nm_rsize = max & ~(NFS_FABLKSIZE - 1);
380 			if (nmp->nm_rsize == 0)
381 				nmp->nm_rsize = max;
382 		}
383 		pref = fxdr_unsigned(u_int32_t, fsp->fs_dtpref);
384 		if (pref < nmp->nm_readdirsize && pref >= NFS_DIRBLKSIZ)
385 			nmp->nm_readdirsize = (pref + NFS_DIRBLKSIZ - 1) &
386 				~(NFS_DIRBLKSIZ - 1);
387 		if (max < nmp->nm_readdirsize && max > 0) {
388 			nmp->nm_readdirsize = max & ~(NFS_DIRBLKSIZ - 1);
389 			if (nmp->nm_readdirsize == 0)
390 				nmp->nm_readdirsize = max;
391 		}
392 		maxfsize = fxdr_hyper(&fsp->fs_maxfilesize);
393 		if (maxfsize > 0 && maxfsize < nmp->nm_maxfilesize)
394 			nmp->nm_maxfilesize = maxfsize;
395 		nmp->nm_state |= NFSSTA_GOTFSINFO;
396 	}
397 	m_freem(mrep);
398 nfsmout:
399 	return (error);
400 }
401 
402 /*
403  * Mount a remote root fs via. nfs. This depends on the info in the
404  * nfs_diskless structure that has been filled in properly by some primary
405  * bootstrap.
406  * It goes something like this:
407  * - do enough of "ifconfig" by calling ifioctl() so that the system
408  *   can talk to the server
409  * - If nfs_diskless.mygateway is filled in, use that address as
410  *   a default gateway.
411  * - build the rootfs mount point and call mountnfs() to do the rest.
412  */
413 int
414 nfs_mountroot(mp)
415 	struct mount *mp;
416 {
417 	struct mount  *swap_mp;
418 	struct nfsv3_diskless *nd = &nfsv3_diskless;
419 	struct socket *so;
420 	struct vnode *vp;
421 	struct thread *td = curthread;		/* XXX */
422 	int error, i;
423 	u_long l;
424 	char buf[128];
425 
426 #if defined(BOOTP_NFSROOT) && defined(BOOTP)
427 	bootpc_init();		/* use bootp to get nfs_diskless filled in */
428 #endif
429 
430 	/*
431 	 * XXX time must be non-zero when we init the interface or else
432 	 * the arp code will wedge...
433 	 */
434 	while (mycpu->gd_time_seconds == 0)
435 		tsleep(mycpu, 0, "arpkludge", 10);
436 
437 	if (nfs_diskless_valid==1)
438 	  nfs_convert_diskless();
439 
440 	/*
441 	 * XXX splnet, so networks will receive...
442 	 */
443 	splnet();
444 
445 #ifdef notyet
446 	/* Set up swap credentials. */
447 	proc0.p_ucred->cr_uid = ntohl(nd->swap_ucred.cr_uid);
448 	proc0.p_ucred->cr_gid = ntohl(nd->swap_ucred.cr_gid);
449 	if ((proc0.p_ucred->cr_ngroups = ntohs(nd->swap_ucred.cr_ngroups)) >
450 		NGROUPS)
451 		proc0.p_ucred->cr_ngroups = NGROUPS;
452 	for (i = 0; i < proc0.p_ucred->cr_ngroups; i++)
453 	    proc0.p_ucred->cr_groups[i] = ntohl(nd->swap_ucred.cr_groups[i]);
454 #endif
455 
456 	/*
457 	 * Do enough of ifconfig(8) so that the critical net interface can
458 	 * talk to the server.
459 	 */
460 	error = socreate(nd->myif.ifra_addr.sa_family, &so, SOCK_DGRAM, 0, td);
461 	if (error)
462 		panic("nfs_mountroot: socreate(%04x): %d",
463 			nd->myif.ifra_addr.sa_family, error);
464 
465 #if 0 /* XXX Bad idea */
466 	/*
467 	 * We might not have been told the right interface, so we pass
468 	 * over the first ten interfaces of the same kind, until we get
469 	 * one of them configured.
470 	 */
471 
472 	for (i = strlen(nd->myif.ifra_name) - 1;
473 		nd->myif.ifra_name[i] >= '0' &&
474 		nd->myif.ifra_name[i] <= '9';
475 		nd->myif.ifra_name[i] ++) {
476 		error = ifioctl(so, SIOCAIFADDR, (caddr_t)&nd->myif, td);
477 		if(!error)
478 			break;
479 	}
480 #endif
481 	error = ifioctl(so, SIOCAIFADDR, (caddr_t)&nd->myif, td);
482 	if (error)
483 		panic("nfs_mountroot: SIOCAIFADDR: %d", error);
484 	soclose(so);
485 
486 	/*
487 	 * If the gateway field is filled in, set it as the default route.
488 	 */
489 	if (nd->mygateway.sin_len != 0) {
490 		struct sockaddr_in mask, sin;
491 
492 		bzero((caddr_t)&mask, sizeof(mask));
493 		sin = mask;
494 		sin.sin_family = AF_INET;
495 		sin.sin_len = sizeof(sin);
496 		error = rtrequest(RTM_ADD, (struct sockaddr *)&sin,
497 		    (struct sockaddr *)&nd->mygateway,
498 		    (struct sockaddr *)&mask,
499 		    RTF_UP | RTF_GATEWAY, (struct rtentry **)0);
500 		if (error)
501 			panic("nfs_mountroot: RTM_ADD: %d", error);
502 	}
503 
504 	/*
505 	 * Create the rootfs mount point.
506 	 */
507 	nd->root_args.fh = nd->root_fh;
508 	nd->root_args.fhsize = nd->root_fhsize;
509 	l = ntohl(nd->root_saddr.sin_addr.s_addr);
510 	snprintf(buf, sizeof(buf), "%ld.%ld.%ld.%ld:%s",
511 		(l >> 24) & 0xff, (l >> 16) & 0xff,
512 		(l >>  8) & 0xff, (l >>  0) & 0xff,nd->root_hostnam);
513 	printf("NFS ROOT: %s\n",buf);
514 	if ((error = nfs_mountdiskless(buf, "/", MNT_RDONLY,
515 	    &nd->root_saddr, &nd->root_args, td, &vp, &mp)) != 0) {
516 		if (swap_mp) {
517 			mp->mnt_vfc->vfc_refcount--;
518 			free(swap_mp, M_MOUNT);
519 		}
520 		return (error);
521 	}
522 
523 	swap_mp = NULL;
524 	if (nd->swap_nblks) {
525 
526 		/* Convert to DEV_BSIZE instead of Kilobyte */
527 		nd->swap_nblks *= 2;
528 
529 		/*
530 		 * Create a fake mount point just for the swap vnode so that the
531 		 * swap file can be on a different server from the rootfs.
532 		 */
533 		nd->swap_args.fh = nd->swap_fh;
534 		nd->swap_args.fhsize = nd->swap_fhsize;
535 		l = ntohl(nd->swap_saddr.sin_addr.s_addr);
536 		snprintf(buf, sizeof(buf), "%ld.%ld.%ld.%ld:%s",
537 			(l >> 24) & 0xff, (l >> 16) & 0xff,
538 			(l >>  8) & 0xff, (l >>  0) & 0xff,nd->swap_hostnam);
539 		printf("NFS SWAP: %s\n",buf);
540 		if ((error = nfs_mountdiskless(buf, "/swap", 0,
541 		    &nd->swap_saddr, &nd->swap_args, td, &vp, &swap_mp)) != 0)
542 			return (error);
543 		vfs_unbusy(swap_mp, td);
544 
545 		VTONFS(vp)->n_size = VTONFS(vp)->n_vattr.va_size =
546 				nd->swap_nblks * DEV_BSIZE ;
547 
548 		/*
549 		 * Since the swap file is not the root dir of a file system,
550 		 * hack it to a regular file.
551 		 */
552 		vp->v_type = VREG;
553 		vp->v_flag = 0;
554 		VREF(vp);
555 		swaponvp(td, vp, NODEV, nd->swap_nblks);
556 	}
557 
558 	mp->mnt_flag |= MNT_ROOTFS;
559 	mp->mnt_vnodecovered = NULLVP;
560 	rootvp = vp;
561 	vfs_unbusy(mp, td);
562 
563 	/*
564 	 * This is not really an nfs issue, but it is much easier to
565 	 * set hostname here and then let the "/etc/rc.xxx" files
566 	 * mount the right /var based upon its preset value.
567 	 */
568 	bcopy(nd->my_hostnam, hostname, MAXHOSTNAMELEN);
569 	hostname[MAXHOSTNAMELEN - 1] = '\0';
570 	for (i = 0; i < MAXHOSTNAMELEN; i++)
571 		if (hostname[i] == '\0')
572 			break;
573 	inittodr(ntohl(nd->root_time));
574 	return (0);
575 }
576 
577 /*
578  * Internal version of mount system call for diskless setup.
579  */
580 static int
581 nfs_mountdiskless(char *path, char *which, int mountflag,
582 	struct sockaddr_in *sin, struct nfs_args *args, struct thread *td,
583 	struct vnode **vpp, struct mount **mpp)
584 {
585 	struct mount *mp;
586 	struct sockaddr *nam;
587 	int error;
588 	int didalloc = 0;
589 
590 	mp = *mpp;
591 
592 	if (mp == NULL) {
593 		if ((error = vfs_rootmountalloc("nfs", path, &mp)) != 0) {
594 			printf("nfs_mountroot: NFS not configured");
595 			return (error);
596 		}
597 		didalloc = 1;
598 	}
599 
600 	mp->mnt_kern_flag = 0;
601 	mp->mnt_flag = mountflag;
602 	nam = dup_sockaddr((struct sockaddr *)sin, 1);
603 	if ((error = mountnfs(args, mp, nam, which, path, vpp)) != 0) {
604 		printf("nfs_mountroot: mount %s on %s: %d", path, which, error);
605 		mp->mnt_vfc->vfc_refcount--;
606 		vfs_unbusy(mp, td);
607 		if (didalloc)
608 			free(mp, M_MOUNT);
609 		FREE(nam, M_SONAME);
610 		return (error);
611 	}
612 	(void) copystr(which, mp->mnt_stat.f_mntonname, MNAMELEN - 1, 0);
613 	*mpp = mp;
614 	return (0);
615 }
616 
617 static void
618 nfs_decode_args(nmp, argp)
619 	struct nfsmount *nmp;
620 	struct nfs_args *argp;
621 {
622 	int s;
623 	int adjsock;
624 	int maxio;
625 
626 	s = splnet();
627 	/*
628 	 * Silently clear NFSMNT_NOCONN if it's a TCP mount, it makes
629 	 * no sense in that context.
630 	 */
631 	if (argp->sotype == SOCK_STREAM)
632 		nmp->nm_flag &= ~NFSMNT_NOCONN;
633 
634 	/* Also clear RDIRPLUS if not NFSv3, it crashes some servers */
635 	if ((argp->flags & NFSMNT_NFSV3) == 0)
636 		nmp->nm_flag &= ~NFSMNT_RDIRPLUS;
637 
638 	/* Re-bind if rsrvd port requested and wasn't on one */
639 	adjsock = !(nmp->nm_flag & NFSMNT_RESVPORT)
640 		  && (argp->flags & NFSMNT_RESVPORT);
641 	/* Also re-bind if we're switching to/from a connected UDP socket */
642 	adjsock |= ((nmp->nm_flag & NFSMNT_NOCONN) !=
643 		    (argp->flags & NFSMNT_NOCONN));
644 
645 	/* Update flags atomically.  Don't change the lock bits. */
646 	nmp->nm_flag = argp->flags | nmp->nm_flag;
647 	splx(s);
648 
649 	if ((argp->flags & NFSMNT_TIMEO) && argp->timeo > 0) {
650 		nmp->nm_timeo = (argp->timeo * NFS_HZ + 5) / 10;
651 		if (nmp->nm_timeo < NFS_MINTIMEO)
652 			nmp->nm_timeo = NFS_MINTIMEO;
653 		else if (nmp->nm_timeo > NFS_MAXTIMEO)
654 			nmp->nm_timeo = NFS_MAXTIMEO;
655 	}
656 
657 	if ((argp->flags & NFSMNT_RETRANS) && argp->retrans > 1) {
658 		nmp->nm_retry = argp->retrans;
659 		if (nmp->nm_retry > NFS_MAXREXMIT)
660 			nmp->nm_retry = NFS_MAXREXMIT;
661 	}
662 
663 	maxio = nfs_iosize(argp->flags & NFSMNT_NFSV3, argp->sotype);
664 
665 	if ((argp->flags & NFSMNT_WSIZE) && argp->wsize > 0) {
666 		nmp->nm_wsize = argp->wsize;
667 		/* Round down to multiple of blocksize */
668 		nmp->nm_wsize &= ~(NFS_FABLKSIZE - 1);
669 		if (nmp->nm_wsize <= 0)
670 			nmp->nm_wsize = NFS_FABLKSIZE;
671 	}
672 	if (nmp->nm_wsize > maxio)
673 		nmp->nm_wsize = maxio;
674 	if (nmp->nm_wsize > MAXBSIZE)
675 		nmp->nm_wsize = MAXBSIZE;
676 
677 	if ((argp->flags & NFSMNT_RSIZE) && argp->rsize > 0) {
678 		nmp->nm_rsize = argp->rsize;
679 		/* Round down to multiple of blocksize */
680 		nmp->nm_rsize &= ~(NFS_FABLKSIZE - 1);
681 		if (nmp->nm_rsize <= 0)
682 			nmp->nm_rsize = NFS_FABLKSIZE;
683 	}
684 	if (nmp->nm_rsize > maxio)
685 		nmp->nm_rsize = maxio;
686 	if (nmp->nm_rsize > MAXBSIZE)
687 		nmp->nm_rsize = MAXBSIZE;
688 
689 	if ((argp->flags & NFSMNT_READDIRSIZE) && argp->readdirsize > 0) {
690 		nmp->nm_readdirsize = argp->readdirsize;
691 	}
692 	if (nmp->nm_readdirsize > maxio)
693 		nmp->nm_readdirsize = maxio;
694 	if (nmp->nm_readdirsize > nmp->nm_rsize)
695 		nmp->nm_readdirsize = nmp->nm_rsize;
696 
697 	if ((argp->flags & NFSMNT_ACREGMIN) && argp->acregmin >= 0)
698 		nmp->nm_acregmin = argp->acregmin;
699 	else
700 		nmp->nm_acregmin = NFS_MINATTRTIMO;
701 	if ((argp->flags & NFSMNT_ACREGMAX) && argp->acregmax >= 0)
702 		nmp->nm_acregmax = argp->acregmax;
703 	else
704 		nmp->nm_acregmax = NFS_MAXATTRTIMO;
705 	if ((argp->flags & NFSMNT_ACDIRMIN) && argp->acdirmin >= 0)
706 		nmp->nm_acdirmin = argp->acdirmin;
707 	else
708 		nmp->nm_acdirmin = NFS_MINDIRATTRTIMO;
709 	if ((argp->flags & NFSMNT_ACDIRMAX) && argp->acdirmax >= 0)
710 		nmp->nm_acdirmax = argp->acdirmax;
711 	else
712 		nmp->nm_acdirmax = NFS_MAXDIRATTRTIMO;
713 	if (nmp->nm_acdirmin > nmp->nm_acdirmax)
714 		nmp->nm_acdirmin = nmp->nm_acdirmax;
715 	if (nmp->nm_acregmin > nmp->nm_acregmax)
716 		nmp->nm_acregmin = nmp->nm_acregmax;
717 
718 	if ((argp->flags & NFSMNT_MAXGRPS) && argp->maxgrouplist >= 0) {
719 		if (argp->maxgrouplist <= NFS_MAXGRPS)
720 			nmp->nm_numgrps = argp->maxgrouplist;
721 		else
722 			nmp->nm_numgrps = NFS_MAXGRPS;
723 	}
724 	if ((argp->flags & NFSMNT_READAHEAD) && argp->readahead >= 0) {
725 		if (argp->readahead <= NFS_MAXRAHEAD)
726 			nmp->nm_readahead = argp->readahead;
727 		else
728 			nmp->nm_readahead = NFS_MAXRAHEAD;
729 	}
730 	if ((argp->flags & NFSMNT_LEASETERM) && argp->leaseterm >= 2) {
731 		if (argp->leaseterm <= NQ_MAXLEASE)
732 			nmp->nm_leaseterm = argp->leaseterm;
733 		else
734 			nmp->nm_leaseterm = NQ_MAXLEASE;
735 	}
736 	if ((argp->flags & NFSMNT_DEADTHRESH) && argp->deadthresh >= 1) {
737 		if (argp->deadthresh <= NQ_NEVERDEAD)
738 			nmp->nm_deadthresh = argp->deadthresh;
739 		else
740 			nmp->nm_deadthresh = NQ_NEVERDEAD;
741 	}
742 
743 	adjsock |= ((nmp->nm_sotype != argp->sotype) ||
744 		    (nmp->nm_soproto != argp->proto));
745 	nmp->nm_sotype = argp->sotype;
746 	nmp->nm_soproto = argp->proto;
747 
748 	if (nmp->nm_so && adjsock) {
749 		nfs_safedisconnect(nmp);
750 		if (nmp->nm_sotype == SOCK_DGRAM)
751 			while (nfs_connect(nmp, (struct nfsreq *)0)) {
752 				printf("nfs_args: retrying connect\n");
753 				(void) tsleep((caddr_t)&lbolt, 0, "nfscon", 0);
754 			}
755 	}
756 }
757 
758 /*
759  * VFS Operations.
760  *
761  * mount system call
762  * It seems a bit dumb to copyinstr() the host and path here and then
763  * bcopy() them in mountnfs(), but I wanted to detect errors before
764  * doing the sockargs() call because sockargs() allocates an mbuf and
765  * an error after that means that I have to release the mbuf.
766  */
767 /* ARGSUSED */
768 static int
769 nfs_mount(struct mount *mp, char *path, caddr_t data,
770 	struct nameidata *ndp, struct thread *td)
771 {
772 	int error;
773 	struct nfs_args args;
774 	struct sockaddr *nam;
775 	struct vnode *vp;
776 	char pth[MNAMELEN], hst[MNAMELEN];
777 	size_t len;
778 	u_char nfh[NFSX_V3FHMAX];
779 
780 	if (path == NULL) {
781 		nfs_mountroot(mp);
782 		return (0);
783 	}
784 	error = copyin(data, (caddr_t)&args, sizeof (struct nfs_args));
785 	if (error)
786 		return (error);
787 	if (args.version != NFS_ARGSVERSION) {
788 #ifdef COMPAT_PRELITE2
789 		/*
790 		 * If the argument version is unknown, then assume the
791 		 * caller is a pre-lite2 4.4BSD client and convert its
792 		 * arguments.
793 		 */
794 		struct onfs_args oargs;
795 		error = copyin(data, (caddr_t)&oargs, sizeof (struct onfs_args));
796 		if (error)
797 			return (error);
798 		nfs_convert_oargs(&args,&oargs);
799 #else /* !COMPAT_PRELITE2 */
800 		return (EPROGMISMATCH);
801 #endif /* COMPAT_PRELITE2 */
802 	}
803 	if (mp->mnt_flag & MNT_UPDATE) {
804 		struct nfsmount *nmp = VFSTONFS(mp);
805 
806 		if (nmp == NULL)
807 			return (EIO);
808 		/*
809 		 * When doing an update, we can't change from or to
810 		 * v3 and/or nqnfs, or change cookie translation
811 		 */
812 		args.flags = (args.flags &
813 		    ~(NFSMNT_NFSV3|NFSMNT_NQNFS /*|NFSMNT_XLATECOOKIE*/)) |
814 		    (nmp->nm_flag &
815 			(NFSMNT_NFSV3|NFSMNT_NQNFS /*|NFSMNT_XLATECOOKIE*/));
816 		nfs_decode_args(nmp, &args);
817 		return (0);
818 	}
819 
820 	/*
821 	 * Make the nfs_ip_paranoia sysctl serve as the default connection
822 	 * or no-connection mode for those protocols that support
823 	 * no-connection mode (the flag will be cleared later for protocols
824 	 * that do not support no-connection mode).  This will allow a client
825 	 * to receive replies from a different IP then the request was
826 	 * sent to.  Note: default value for nfs_ip_paranoia is 1 (paranoid),
827 	 * not 0.
828 	 */
829 	if (nfs_ip_paranoia == 0)
830 		args.flags |= NFSMNT_NOCONN;
831 	if (args.fhsize < 0 || args.fhsize > NFSX_V3FHMAX)
832 		return (EINVAL);
833 	error = copyin((caddr_t)args.fh, (caddr_t)nfh, args.fhsize);
834 	if (error)
835 		return (error);
836 	error = copyinstr(path, pth, MNAMELEN-1, &len);
837 	if (error)
838 		return (error);
839 	bzero(&pth[len], MNAMELEN - len);
840 	error = copyinstr(args.hostname, hst, MNAMELEN-1, &len);
841 	if (error)
842 		return (error);
843 	bzero(&hst[len], MNAMELEN - len);
844 	/* sockargs() call must be after above copyin() calls */
845 	error = getsockaddr(&nam, (caddr_t)args.addr, args.addrlen);
846 	if (error)
847 		return (error);
848 	args.fh = nfh;
849 	error = mountnfs(&args, mp, nam, pth, hst, &vp);
850 	return (error);
851 }
852 
853 /*
854  * Common code for mount and mountroot
855  */
856 static int
857 mountnfs(struct nfs_args *argp, struct mount *mp, struct sockaddr *nam,
858 	char *pth, char *hst, struct vnode **vpp)
859 {
860 	struct nfsmount *nmp;
861 	struct nfsnode *np;
862 	int error;
863 
864 	if (mp->mnt_flag & MNT_UPDATE) {
865 		nmp = VFSTONFS(mp);
866 		/* update paths, file handles, etc, here	XXX */
867 		FREE(nam, M_SONAME);
868 		return (0);
869 	} else {
870 		nmp = zalloc(nfsmount_zone);
871 		bzero((caddr_t)nmp, sizeof (struct nfsmount));
872 		TAILQ_INIT(&nmp->nm_uidlruhead);
873 		TAILQ_INIT(&nmp->nm_bufq);
874 		mp->mnt_data = (qaddr_t)nmp;
875 	}
876 	vfs_getnewfsid(mp);
877 	nmp->nm_mountp = mp;
878 	if (argp->flags & NFSMNT_NQNFS)
879 		/*
880 		 * We have to set mnt_maxsymlink to a non-zero value so
881 		 * that COMPAT_43 routines will know that we are setting
882 		 * the d_type field in directories (and can zero it for
883 		 * unsuspecting binaries).
884 		 */
885 		mp->mnt_maxsymlinklen = 1;
886 
887 	/*
888 	 * V2 can only handle 32 bit filesizes.  A 4GB-1 limit may be too
889 	 * high, depending on whether we end up with negative offsets in
890 	 * the client or server somewhere.  2GB-1 may be safer.
891 	 *
892 	 * For V3, nfs_fsinfo will adjust this as necessary.  Assume maximum
893 	 * that we can handle until we find out otherwise.
894 	 * XXX Our "safe" limit on the client is what we can store in our
895 	 * buffer cache using signed(!) block numbers.
896 	 */
897 	if ((argp->flags & NFSMNT_NFSV3) == 0)
898 		nmp->nm_maxfilesize = 0xffffffffLL;
899 	else
900 		nmp->nm_maxfilesize = (u_int64_t)0x80000000 * DEV_BSIZE - 1;
901 
902 	nmp->nm_timeo = NFS_TIMEO;
903 	nmp->nm_retry = NFS_RETRANS;
904 	nmp->nm_wsize = nfs_iosize(argp->flags & NFSMNT_NFSV3, argp->sotype);
905 	nmp->nm_rsize = nmp->nm_wsize;
906 	nmp->nm_readdirsize = NFS_READDIRSIZE;
907 	nmp->nm_numgrps = NFS_MAXGRPS;
908 	nmp->nm_readahead = NFS_DEFRAHEAD;
909 	nmp->nm_leaseterm = NQ_DEFLEASE;
910 	nmp->nm_deadthresh = NQ_DEADTHRESH;
911 	CIRCLEQ_INIT(&nmp->nm_timerhead);
912 	nmp->nm_inprog = NULLVP;
913 	nmp->nm_fhsize = argp->fhsize;
914 	bcopy((caddr_t)argp->fh, (caddr_t)nmp->nm_fh, argp->fhsize);
915 	bcopy(hst, mp->mnt_stat.f_mntfromname, MNAMELEN);
916 	bcopy(pth, mp->mnt_stat.f_mntonname, MNAMELEN);
917 	nmp->nm_nam = nam;
918 	/* Set up the sockets and per-host congestion */
919 	nmp->nm_sotype = argp->sotype;
920 	nmp->nm_soproto = argp->proto;
921 	nmp->nm_cred = crhold(proc0.p_ucred);
922 
923 	nfs_decode_args(nmp, argp);
924 
925 	/*
926 	 * For Connection based sockets (TCP,...) defer the connect until
927 	 * the first request, in case the server is not responding.
928 	 */
929 	if (nmp->nm_sotype == SOCK_DGRAM &&
930 		(error = nfs_connect(nmp, (struct nfsreq *)0)))
931 		goto bad;
932 
933 	/*
934 	 * This is silly, but it has to be set so that vinifod() works.
935 	 * We do not want to do an nfs_statfs() here since we can get
936 	 * stuck on a dead server and we are holding a lock on the mount
937 	 * point.
938 	 */
939 	mp->mnt_stat.f_iosize =
940 		nfs_iosize(nmp->nm_flag & NFSMNT_NFSV3, nmp->nm_sotype);
941 
942 	/*
943 	 * A reference count is needed on the nfsnode representing the
944 	 * remote root.  If this object is not persistent, then backward
945 	 * traversals of the mount point (i.e. "..") will not work if
946 	 * the nfsnode gets flushed out of the cache. Ufs does not have
947 	 * this problem, because one can identify root inodes by their
948 	 * number == ROOTINO (2).
949 	 */
950 	error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
951 	if (error)
952 		goto bad;
953 	*vpp = NFSTOV(np);
954 
955 	/*
956 	 * Retrieval of mountpoint attributes is delayed until nfs_rot
957 	 * or nfs_statfs are first called.  This will happen either when
958 	 * we first traverse the mount point or if somebody does a df(1).
959 	 *
960 	 * NFSSTA_GOTFSINFO is used to flag if we have successfully
961 	 * retrieved mountpoint attributes.  In the case of NFSv3 we
962 	 * also flag static fsinfo.
963 	 */
964 	if (*vpp != NULL)
965 		(*vpp)->v_type = VNON;
966 
967 	/*
968 	 * Lose the lock but keep the ref.
969 	 */
970 	VOP_UNLOCK(*vpp, NULL, 0, curthread);
971 
972 	return (0);
973 bad:
974 	nfs_disconnect(nmp);
975 	nfs_free_mount(nmp);
976 	FREE(nam, M_SONAME);
977 	return (error);
978 }
979 
980 /*
981  * unmount system call
982  */
983 static int
984 nfs_unmount(struct mount *mp, int mntflags, struct thread *td)
985 {
986 	struct nfsmount *nmp;
987 	int error, flags = 0;
988 
989 	if (mntflags & MNT_FORCE)
990 		flags |= FORCECLOSE;
991 	nmp = VFSTONFS(mp);
992 	/*
993 	 * Goes something like this..
994 	 * - Call vflush() to clear out vnodes for this file system
995 	 * - Close the socket
996 	 * - Free up the data structures
997 	 */
998 	/* In the forced case, cancel any outstanding requests. */
999 	if (flags & FORCECLOSE) {
1000 		error = nfs_nmcancelreqs(nmp);
1001 		if (error)
1002 			return (error);
1003 	}
1004 	/*
1005 	 * Must handshake with nqnfs_clientd() if it is active.
1006 	 */
1007 	nmp->nm_state |= NFSSTA_DISMINPROG;
1008 	while (nmp->nm_inprog != NULLVP)
1009 		(void) tsleep((caddr_t)&lbolt, 0, "nfsdism", 0);
1010 
1011 	/* We hold 1 extra ref on the root vnode; see comment in mountnfs(). */
1012 	error = vflush(mp, 1, flags);
1013 	if (error) {
1014 		nmp->nm_state &= ~NFSSTA_DISMINPROG;
1015 		return (error);
1016 	}
1017 
1018 	/*
1019 	 * We are now committed to the unmount.
1020 	 * For NQNFS, let the server daemon free the nfsmount structure.
1021 	 */
1022 	if (nmp->nm_flag & (NFSMNT_NQNFS | NFSMNT_KERB))
1023 		nmp->nm_state |= NFSSTA_DISMNT;
1024 
1025 	nfs_disconnect(nmp);
1026 	FREE(nmp->nm_nam, M_SONAME);
1027 
1028 	if ((nmp->nm_flag & (NFSMNT_NQNFS | NFSMNT_KERB)) == 0)
1029 		nfs_free_mount(nmp);
1030 	return (0);
1031 }
1032 
1033 void
1034 nfs_free_mount(struct nfsmount *nmp)
1035 {
1036 	if (nmp->nm_cred)  {
1037 		crfree(nmp->nm_cred);
1038 		nmp->nm_cred = NULL;
1039 	}
1040 	zfree(nfsmount_zone, nmp);
1041 }
1042 
1043 /*
1044  * Return root of a filesystem
1045  */
1046 static int
1047 nfs_root(mp, vpp)
1048 	struct mount *mp;
1049 	struct vnode **vpp;
1050 {
1051 	struct vnode *vp;
1052 	struct nfsmount *nmp;
1053 	struct vattr attrs;
1054 	struct nfsnode *np;
1055 	int error;
1056 
1057 	nmp = VFSTONFS(mp);
1058 	error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
1059 	if (error)
1060 		return (error);
1061 	vp = NFSTOV(np);
1062 
1063 	/*
1064 	 * Get transfer parameters and root vnode attributes
1065 	 */
1066 	if ((nmp->nm_state & NFSSTA_GOTFSINFO) == 0) {
1067 	    if (nmp->nm_flag & NFSMNT_NFSV3) {
1068 		nfs_fsinfo(nmp, vp, curthread);
1069 		mp->mnt_stat.f_iosize = nfs_iosize(1, nmp->nm_sotype);
1070 	    } else {
1071 		if ((error = VOP_GETATTR(vp, &attrs, curthread)) == 0)
1072 			nmp->nm_state |= NFSSTA_GOTFSINFO;
1073 
1074 	    }
1075 	}
1076 	if (vp->v_type == VNON)
1077 	    vp->v_type = VDIR;
1078 	vp->v_flag = VROOT;
1079 	*vpp = vp;
1080 	return (0);
1081 }
1082 
1083 extern int syncprt;
1084 
1085 struct scaninfo {
1086 	int rescan;
1087 	thread_t td;
1088 	int waitfor;
1089 	int allerror;
1090 };
1091 
1092 static int nfs_sync_scan1(struct mount *mp, struct vnode *vp, void *data);
1093 static int nfs_sync_scan2(struct mount *mp, struct vnode *vp, lwkt_tokref_t vlock, void *data);
1094 
1095 /*
1096  * Flush out the buffer cache
1097  */
1098 /* ARGSUSED */
1099 static int
1100 nfs_sync(struct mount *mp, int waitfor, struct thread *td)
1101 {
1102 	struct scaninfo scaninfo;
1103 	int error;
1104 
1105 	scaninfo.rescan = 0;
1106 	scaninfo.td = td;
1107 	scaninfo.waitfor = waitfor;
1108 	scaninfo.allerror = 0;
1109 
1110 	/*
1111 	 * Force stale buffer cache information to be flushed.
1112 	 */
1113 	error = 0;
1114 	while (error == 0 && scaninfo.rescan) {
1115 		scaninfo.rescan = 0;
1116 		error = vmntvnodescan(mp, nfs_sync_scan1,
1117 					nfs_sync_scan2, &scaninfo);
1118 	}
1119 	return(error);
1120 }
1121 
1122 static
1123 int
1124 nfs_sync_scan1(struct mount *mp, struct vnode *vp, void *data)
1125 {
1126     struct scaninfo *info = data;
1127 
1128     if (VOP_ISLOCKED(vp, NULL) || TAILQ_EMPTY(&vp->v_dirtyblkhd))
1129 	return(-1);
1130     if (info->waitfor == MNT_LAZY)
1131 	return(-1);
1132     return(0);
1133 }
1134 
1135 static
1136 int
1137 nfs_sync_scan2(struct mount *mp, struct vnode *vp, lwkt_tokref_t vlock, void *data)
1138 {
1139     struct scaninfo *info = data;
1140     int error;
1141 
1142     if (vget(vp, vlock, LK_EXCLUSIVE | LK_INTERLOCK, info->td)) {
1143 	info->rescan = 1;
1144 	return(0);
1145     }
1146     error = VOP_FSYNC(vp, info->waitfor, info->td);
1147     if (error)
1148 	info->allerror = error;
1149     vput(vp);
1150     return(0);
1151 }
1152 
1153