xref: /dflybsd-src/sys/vfs/nfs/nfs_vfsops.c (revision d2d1103f52e6fb116ee65a9940477c5449933f28)
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 1.54 2008/07/31 20:23:40 swildner Exp $
39  */
40 
41 #include "opt_bootp.h"
42 #include "opt_nfsroot.h"
43 
44 #include <sys/param.h>
45 #include <sys/sockio.h>
46 #include <sys/proc.h>
47 #include <sys/vnode.h>
48 #include <sys/fcntl.h>
49 #include <sys/kernel.h>
50 #include <sys/sysctl.h>
51 #include <sys/malloc.h>
52 #include <sys/mount.h>
53 #include <sys/mbuf.h>
54 #include <sys/socket.h>
55 #include <sys/socketvar.h>
56 #include <sys/systm.h>
57 
58 #include <vm/vm.h>
59 #include <vm/vm_extern.h>
60 #include <vm/vm_zone.h>
61 
62 #include <net/if.h>
63 #include <net/route.h>
64 #include <netinet/in.h>
65 
66 #include <sys/thread2.h>
67 #include <sys/mutex2.h>
68 
69 #include "rpcv2.h"
70 #include "nfsproto.h"
71 #include "nfs.h"
72 #include "nfsmount.h"
73 #include "nfsnode.h"
74 #include "xdr_subs.h"
75 #include "nfsm_subs.h"
76 #include "nfsdiskless.h"
77 #include "nfsmountrpc.h"
78 
79 extern int	nfs_mountroot(struct mount *mp);
80 extern void	bootpc_init(void);
81 
82 extern struct vop_ops nfsv2_vnode_vops;
83 extern struct vop_ops nfsv2_fifo_vops;
84 extern struct vop_ops nfsv2_spec_vops;
85 
86 MALLOC_DEFINE(M_NFSREQ, "NFS req", "NFS request header");
87 MALLOC_DEFINE(M_NFSBIGFH, "NFSV3 bigfh", "NFS version 3 file handle");
88 MALLOC_DEFINE(M_NFSD, "NFS daemon", "Nfs server daemon structure");
89 MALLOC_DEFINE(M_NFSDIROFF, "NFSV3 diroff", "NFS directory offset data");
90 MALLOC_DEFINE(M_NFSRVDESC, "NFSV3 srvdesc", "NFS server socket descriptor");
91 MALLOC_DEFINE(M_NFSUID, "NFS uid", "Nfs uid mapping structure");
92 MALLOC_DEFINE(M_NFSHASH, "NFS hash", "NFS hash tables");
93 
94 vm_zone_t nfsmount_zone;
95 
96 struct nfsstats	nfsstats;
97 SYSCTL_NODE(_vfs, OID_AUTO, nfs, CTLFLAG_RW, 0, "NFS filesystem");
98 SYSCTL_STRUCT(_vfs_nfs, NFS_NFSSTATS, nfsstats, CTLFLAG_RD,
99 	&nfsstats, nfsstats, "");
100 static int nfs_ip_paranoia = 1;
101 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_ip_paranoia, CTLFLAG_RW,
102 	&nfs_ip_paranoia, 0, "");
103 #ifdef NFS_DEBUG
104 int nfs_debug;
105 SYSCTL_INT(_vfs_nfs, OID_AUTO, debug, CTLFLAG_RW, &nfs_debug, 0, "");
106 #endif
107 
108 /*
109  * Tunable to determine the Read/Write unit size.  Maximum value
110  * is NFS_MAXDATA.  We also default to NFS_MAXDATA.
111  */
112 static int nfs_io_size = NFS_MAXDATA;
113 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_io_size, CTLFLAG_RW,
114 	&nfs_io_size, 0, "NFS optimal I/O unit size");
115 
116 static void	nfs_decode_args (struct nfsmount *nmp,
117 			struct nfs_args *argp);
118 static int	mountnfs (struct nfs_args *,struct mount *,
119 			struct sockaddr *,char *,char *,struct vnode **);
120 static int	nfs_mount ( struct mount *mp, char *path, caddr_t data,
121 			struct ucred *cred);
122 static int	nfs_unmount ( struct mount *mp, int mntflags);
123 static int	nfs_root ( struct mount *mp, struct vnode **vpp);
124 static int	nfs_statfs ( struct mount *mp, struct statfs *sbp,
125 			struct ucred *cred);
126 static int	nfs_statvfs(struct mount *mp, struct statvfs *sbp,
127 				struct ucred *cred);
128 static int	nfs_sync ( struct mount *mp, int waitfor);
129 
130 /*
131  * nfs vfs operations.
132  */
133 static struct vfsops nfs_vfsops = {
134 	.vfs_mount =    	nfs_mount,
135 	.vfs_unmount =  	nfs_unmount,
136 	.vfs_root =     	nfs_root,
137 	.vfs_statfs =    	nfs_statfs,
138 	.vfs_statvfs =   	nfs_statvfs,
139 	.vfs_sync =     	nfs_sync,
140 	.vfs_init =     	nfs_init,
141 	.vfs_uninit =    	nfs_uninit
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 int
190 nfs_iosize(int v3, int sotype)
191 {
192 	int iosize;
193 	int iomax;
194 
195 	if (v3) {
196 		if (sotype == SOCK_STREAM)
197 			iomax = NFS_MAXDATA;
198 		else
199 			iomax = NFS_MAXDGRAMDATA;
200 	} else {
201 		iomax = NFS_V2MAXDATA;
202 	}
203 	if ((iosize = nfs_io_size) > iomax)
204 		iosize = iomax;
205 	if (iosize < PAGE_SIZE)
206 		iosize = PAGE_SIZE;
207 
208 	/*
209 	 * This is an aweful hack but until the buffer cache is rewritten
210 	 * we need it.  The problem is that when you combine write() with
211 	 * mmap() the vm_page->valid bits can become weird looking
212 	 * (e.g. 0xfc).  This occurs because NFS uses piecemeal buffers
213 	 * at the file EOF.  To solve the problem the BIO system needs to
214 	 * be guarenteed that the NFS iosize for regular files will be a
215 	 * multiple of PAGE_SIZE so it can invalidate the whole page
216 	 * rather then just the piece of it owned by the buffer when
217 	 * NFS does vinvalbuf() calls.
218 	 */
219 	if (iosize & PAGE_MASK)
220 		iosize = (iosize & ~PAGE_MASK) + PAGE_SIZE;
221 	return iosize;
222 }
223 
224 static void
225 nfs_convert_oargs(struct nfs_args *args, struct onfs_args *oargs)
226 {
227 	args->version = NFS_ARGSVERSION;
228 	args->addr = oargs->addr;
229 	args->addrlen = oargs->addrlen;
230 	args->sotype = oargs->sotype;
231 	args->proto = oargs->proto;
232 	args->fh = oargs->fh;
233 	args->fhsize = oargs->fhsize;
234 	args->flags = oargs->flags;
235 	args->wsize = oargs->wsize;
236 	args->rsize = oargs->rsize;
237 	args->readdirsize = oargs->readdirsize;
238 	args->timeo = oargs->timeo;
239 	args->retrans = oargs->retrans;
240 	args->maxgrouplist = oargs->maxgrouplist;
241 	args->readahead = oargs->readahead;
242 	args->deadthresh = oargs->deadthresh;
243 	args->hostname = oargs->hostname;
244 }
245 
246 static void
247 nfs_convert_diskless(void)
248 {
249 	int i;
250 
251 	bcopy(&nfs_diskless.myif, &nfsv3_diskless.myif,
252 		sizeof(struct ifaliasreq));
253 	bcopy(&nfs_diskless.mygateway, &nfsv3_diskless.mygateway,
254 		sizeof(struct sockaddr_in));
255 	nfs_convert_oargs(&nfsv3_diskless.swap_args,&nfs_diskless.swap_args);
256 
257 	bcopy(nfs_diskless.swap_fh,nfsv3_diskless.swap_fh,NFSX_V2FH);
258 	nfsv3_diskless.swap_fhsize = NFSX_V2FH;
259 	for (i = NFSX_V2FH - 1; i >= 0; --i) {
260 		if (nfs_diskless.swap_fh[i])
261 			break;
262 	}
263 	if (i < 0)
264 		nfsv3_diskless.swap_fhsize = 0;
265 
266 	bcopy(&nfs_diskless.swap_saddr,&nfsv3_diskless.swap_saddr,
267 		sizeof(struct sockaddr_in));
268 	bcopy(nfs_diskless.swap_hostnam,nfsv3_diskless.swap_hostnam, MNAMELEN);
269 	nfsv3_diskless.swap_nblks = nfs_diskless.swap_nblks;
270 	bcopy(&nfs_diskless.swap_ucred, &nfsv3_diskless.swap_ucred,
271 		sizeof(struct ucred));
272 	nfs_convert_oargs(&nfsv3_diskless.root_args,&nfs_diskless.root_args);
273 
274 	bcopy(nfs_diskless.root_fh,nfsv3_diskless.root_fh,NFSX_V2FH);
275 	nfsv3_diskless.root_fhsize = NFSX_V2FH;
276 	for (i = NFSX_V2FH - 1; i >= 0; --i) {
277 		if (nfs_diskless.root_fh[i])
278 			break;
279 	}
280 	if (i < 0)
281 		nfsv3_diskless.root_fhsize = 0;
282 
283 	bcopy(&nfs_diskless.root_saddr,&nfsv3_diskless.root_saddr,
284 		sizeof(struct sockaddr_in));
285 	bcopy(nfs_diskless.root_hostnam,nfsv3_diskless.root_hostnam, MNAMELEN);
286 	nfsv3_diskless.root_time = nfs_diskless.root_time;
287 	bcopy(nfs_diskless.my_hostnam,nfsv3_diskless.my_hostnam,
288 		MAXHOSTNAMELEN);
289 	nfs_diskless_valid = 3;
290 }
291 
292 /*
293  * nfs statfs call
294  */
295 int
296 nfs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
297 {
298 	struct vnode *vp;
299 	struct nfs_statfs *sfp;
300 	struct nfsmount *nmp = VFSTONFS(mp);
301 	thread_t td = curthread;
302 	int error = 0, retattr;
303 	struct nfsnode *np;
304 	u_quad_t tquad;
305 	struct nfsm_info info;
306 
307 	info.mrep = NULL;
308 	info.v3 = (nmp->nm_flag & NFSMNT_NFSV3);
309 
310 	lwkt_gettoken(&nmp->nm_token);
311 
312 #ifndef nolint
313 	sfp = NULL;
314 #endif
315 	error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
316 	if (error) {
317 		lwkt_reltoken(&nmp->nm_token);
318 		return (error);
319 	}
320 	vp = NFSTOV(np);
321 	/* ignore the passed cred */
322 	cred = crget();
323 	cred->cr_ngroups = 1;
324 	if (info.v3 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0)
325 		(void)nfs_fsinfo(nmp, vp, td);
326 	nfsstats.rpccnt[NFSPROC_FSSTAT]++;
327 	nfsm_reqhead(&info, vp, NFSPROC_FSSTAT, NFSX_FH(info.v3));
328 	ERROROUT(nfsm_fhtom(&info, vp));
329 	NEGKEEPOUT(nfsm_request(&info, vp, NFSPROC_FSSTAT, td, cred, &error));
330 	if (info.v3) {
331 		ERROROUT(nfsm_postop_attr(&info, vp, &retattr,
332 					 NFS_LATTR_NOSHRINK));
333 	}
334 	if (error) {
335 		if (info.mrep != NULL)
336 			m_freem(info.mrep);
337 		goto nfsmout;
338 	}
339 	NULLOUT(sfp = nfsm_dissect(&info, NFSX_STATFS(info.v3)));
340 	sbp->f_flags = nmp->nm_flag;
341 
342 	if (info.v3) {
343 		sbp->f_bsize = NFS_FABLKSIZE;
344 		tquad = fxdr_hyper(&sfp->sf_tbytes);
345 		sbp->f_blocks = (long)(tquad / ((u_quad_t)NFS_FABLKSIZE));
346 		tquad = fxdr_hyper(&sfp->sf_fbytes);
347 		sbp->f_bfree = (long)(tquad / ((u_quad_t)NFS_FABLKSIZE));
348 		tquad = fxdr_hyper(&sfp->sf_abytes);
349 		sbp->f_bavail = (long)(tquad / ((u_quad_t)NFS_FABLKSIZE));
350 		sbp->f_files = (fxdr_unsigned(int32_t,
351 		    sfp->sf_tfiles.nfsuquad[1]) & 0x7fffffff);
352 		sbp->f_ffree = (fxdr_unsigned(int32_t,
353 		    sfp->sf_ffiles.nfsuquad[1]) & 0x7fffffff);
354 	} else {
355 		sbp->f_bsize = fxdr_unsigned(int32_t, sfp->sf_bsize);
356 		sbp->f_blocks = fxdr_unsigned(int32_t, sfp->sf_blocks);
357 		sbp->f_bfree = fxdr_unsigned(int32_t, sfp->sf_bfree);
358 		sbp->f_bavail = fxdr_unsigned(int32_t, sfp->sf_bavail);
359 		sbp->f_files = 0;
360 		sbp->f_ffree = 0;
361 	}
362 
363 	/*
364 	 * Some values are pre-set in mnt_stat.  Note in particular f_iosize
365 	 * cannot be changed once the filesystem is mounted as it is used
366 	 * as the basis for BIOs.
367 	 */
368 	if (sbp != &mp->mnt_stat) {
369 		sbp->f_type = mp->mnt_vfc->vfc_typenum;
370 		bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
371 		sbp->f_iosize = mp->mnt_stat.f_iosize;
372 	}
373 	m_freem(info.mrep);
374 	info.mrep = NULL;
375 nfsmout:
376 	vput(vp);
377 	crfree(cred);
378 	lwkt_reltoken(&nmp->nm_token);
379 	return (error);
380 }
381 
382 static int
383 nfs_statvfs(struct mount *mp, struct statvfs *sbp, struct ucred *cred)
384 {
385 	struct vnode *vp;
386 	struct nfs_statfs *sfp;
387 	struct nfsmount *nmp = VFSTONFS(mp);
388 	thread_t td = curthread;
389 	int error = 0, retattr;
390 	struct nfsnode *np;
391 	struct nfsm_info info;
392 
393 	info.mrep = NULL;
394 	info.v3 = (nmp->nm_flag & NFSMNT_NFSV3);
395 	lwkt_gettoken(&nmp->nm_token);
396 
397 #ifndef nolint
398 	sfp = NULL;
399 #endif
400 	error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
401 	if (error) {
402 		lwkt_reltoken(&nmp->nm_token);
403 		return (error);
404 	}
405 	vp = NFSTOV(np);
406 	/* ignore the passed cred */
407 	cred = crget();
408 	cred->cr_ngroups = 1;
409 	if (info.v3 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0)
410 		(void)nfs_fsinfo(nmp, vp, td);
411 	nfsstats.rpccnt[NFSPROC_FSSTAT]++;
412 	nfsm_reqhead(&info, vp, NFSPROC_FSSTAT, NFSX_FH(info.v3));
413 	ERROROUT(nfsm_fhtom(&info, vp));
414 	NEGKEEPOUT(nfsm_request(&info, vp, NFSPROC_FSSTAT, td, cred, &error));
415 	if (info.v3) {
416 		ERROROUT(nfsm_postop_attr(&info, vp, &retattr,
417 					 NFS_LATTR_NOSHRINK));
418 	}
419 	if (error) {
420 		if (info.mrep != NULL)
421 			m_freem(info.mrep);
422 		goto nfsmout;
423 	}
424 	NULLOUT(sfp = nfsm_dissect(&info, NFSX_STATFS(info.v3)));
425 	sbp->f_flag = nmp->nm_flag;
426 	sbp->f_owner = nmp->nm_cred->cr_ruid;
427 
428 	if (info.v3) {
429 		sbp->f_bsize = NFS_FABLKSIZE;
430 		sbp->f_frsize = NFS_FABLKSIZE;
431 		sbp->f_blocks = (fxdr_hyper(&sfp->sf_tbytes) /
432 				((u_quad_t)NFS_FABLKSIZE));
433 		sbp->f_bfree = (fxdr_hyper(&sfp->sf_fbytes) /
434 				((u_quad_t)NFS_FABLKSIZE));
435 		sbp->f_bavail = (fxdr_hyper(&sfp->sf_abytes) /
436 				((u_quad_t)NFS_FABLKSIZE));
437 		sbp->f_files = fxdr_hyper(&sfp->sf_tfiles);
438 		sbp->f_ffree = fxdr_hyper(&sfp->sf_ffiles);
439 		sbp->f_favail = fxdr_hyper(&sfp->sf_afiles);
440 	} else {
441 		sbp->f_bsize = fxdr_unsigned(int32_t, sfp->sf_bsize);
442 		sbp->f_blocks = fxdr_unsigned(int32_t, sfp->sf_blocks);
443 		sbp->f_bfree = fxdr_unsigned(int32_t, sfp->sf_bfree);
444 		sbp->f_bavail = fxdr_unsigned(int32_t, sfp->sf_bavail);
445 		sbp->f_files = 0;
446 		sbp->f_ffree = 0;
447 		sbp->f_favail = 0;
448 	}
449 	sbp->f_syncreads = 0;
450 	sbp->f_syncwrites = 0;
451 	sbp->f_asyncreads = 0;
452 	sbp->f_asyncwrites = 0;
453 	sbp->f_type = mp->mnt_vfc->vfc_typenum;
454 
455 	m_freem(info.mrep);
456 	info.mrep = NULL;
457 nfsmout:
458 	vput(vp);
459 	crfree(cred);
460 	lwkt_reltoken(&nmp->nm_token);
461 	return (error);
462 }
463 
464 /*
465  * nfs version 3 fsinfo rpc call
466  */
467 int
468 nfs_fsinfo(struct nfsmount *nmp, struct vnode *vp, struct thread *td)
469 {
470 	struct nfsv3_fsinfo *fsp;
471 	u_int32_t pref, max;
472 	int error = 0, retattr;
473 	u_int64_t maxfsize;
474 	struct nfsm_info info;
475 
476 	info.v3 = 1;
477 	nfsstats.rpccnt[NFSPROC_FSINFO]++;
478 	nfsm_reqhead(&info, vp, NFSPROC_FSINFO, NFSX_FH(1));
479 	ERROROUT(nfsm_fhtom(&info, vp));
480 	NEGKEEPOUT(nfsm_request(&info, vp, NFSPROC_FSINFO, td,
481 				nfs_vpcred(vp, ND_READ), &error));
482 	ERROROUT(nfsm_postop_attr(&info, vp, &retattr, NFS_LATTR_NOSHRINK));
483 	if (error == 0) {
484 		NULLOUT(fsp = nfsm_dissect(&info, NFSX_V3FSINFO));
485 		pref = fxdr_unsigned(u_int32_t, fsp->fs_wtpref);
486 		if (pref < nmp->nm_wsize && pref >= NFS_FABLKSIZE)
487 			nmp->nm_wsize = (pref + NFS_FABLKSIZE - 1) &
488 				~(NFS_FABLKSIZE - 1);
489 		max = fxdr_unsigned(u_int32_t, fsp->fs_wtmax);
490 		if (max < nmp->nm_wsize && max > 0) {
491 			nmp->nm_wsize = max & ~(NFS_FABLKSIZE - 1);
492 			if (nmp->nm_wsize == 0)
493 				nmp->nm_wsize = max;
494 		}
495 		pref = fxdr_unsigned(u_int32_t, fsp->fs_rtpref);
496 		if (pref < nmp->nm_rsize && pref >= NFS_FABLKSIZE)
497 			nmp->nm_rsize = (pref + NFS_FABLKSIZE - 1) &
498 				~(NFS_FABLKSIZE - 1);
499 		max = fxdr_unsigned(u_int32_t, fsp->fs_rtmax);
500 		if (max < nmp->nm_rsize && max > 0) {
501 			nmp->nm_rsize = max & ~(NFS_FABLKSIZE - 1);
502 			if (nmp->nm_rsize == 0)
503 				nmp->nm_rsize = max;
504 		}
505 		pref = fxdr_unsigned(u_int32_t, fsp->fs_dtpref);
506 		if (pref < nmp->nm_readdirsize && pref >= NFS_DIRBLKSIZ)
507 			nmp->nm_readdirsize = (pref + NFS_DIRBLKSIZ - 1) &
508 				~(NFS_DIRBLKSIZ - 1);
509 		if (max < nmp->nm_readdirsize && max > 0) {
510 			nmp->nm_readdirsize = max & ~(NFS_DIRBLKSIZ - 1);
511 			if (nmp->nm_readdirsize == 0)
512 				nmp->nm_readdirsize = max;
513 		}
514 		maxfsize = fxdr_hyper(&fsp->fs_maxfilesize);
515 		if (maxfsize > 0 && maxfsize < nmp->nm_maxfilesize)
516 			nmp->nm_maxfilesize = maxfsize;
517 		nmp->nm_state |= NFSSTA_GOTFSINFO;
518 
519 		/*
520 		 * Use the smaller of rsize/wsize for the biosize.
521 		 */
522 		if (nmp->nm_rsize < nmp->nm_wsize)
523 			nmp->nm_mountp->mnt_stat.f_iosize = nmp->nm_rsize;
524 		else
525 			nmp->nm_mountp->mnt_stat.f_iosize = nmp->nm_wsize;
526 	}
527 	m_freem(info.mrep);
528 	info.mrep = NULL;
529 nfsmout:
530 	return (error);
531 }
532 
533 /*
534  * Mount a remote root fs via. nfs. This depends on the info in the
535  * nfs_diskless structure that has been filled in properly by some primary
536  * bootstrap.
537  * It goes something like this:
538  * - do enough of "ifconfig" by calling ifioctl() so that the system
539  *   can talk to the server
540  * - If nfs_diskless.mygateway is filled in, use that address as
541  *   a default gateway.
542  * - build the rootfs mount point and call mountnfs() to do the rest.
543  */
544 int
545 nfs_mountroot(struct mount *mp)
546 {
547 	struct mount  *swap_mp;
548 	struct nfsv3_diskless *nd = &nfsv3_diskless;
549 	struct socket *so;
550 	struct vnode *vp;
551 	struct thread *td = curthread;		/* XXX */
552 	int error, i;
553 	u_long l;
554 	char buf[128];
555 
556 #if defined(BOOTP_NFSROOT) && defined(BOOTP)
557 	bootpc_init();		/* use bootp to get nfs_diskless filled in */
558 #endif
559 
560 	/*
561 	 * XXX time must be non-zero when we init the interface or else
562 	 * the arp code will wedge...
563 	 */
564 	while (mycpu->gd_time_seconds == 0)
565 		tsleep(mycpu, 0, "arpkludge", 10);
566 
567 	/*
568 	 * The boot code may have passed us a diskless structure.
569 	 */
570 	if (nfs_diskless_valid == 1)
571 		nfs_convert_diskless();
572 
573 #define SINP(sockaddr)	((struct sockaddr_in *)(sockaddr))
574 	kprintf("nfs_mountroot: interface %s ip %s",
575 		nd->myif.ifra_name,
576 		inet_ntoa(SINP(&nd->myif.ifra_addr)->sin_addr));
577 	kprintf(" bcast %s",
578 		inet_ntoa(SINP(&nd->myif.ifra_broadaddr)->sin_addr));
579 	kprintf(" mask %s\n",
580 		inet_ntoa(SINP(&nd->myif.ifra_mask)->sin_addr));
581 #undef SINP
582 
583 	/*
584 	 * XXX splnet, so networks will receive...
585 	 */
586 	crit_enter();
587 
588 	/*
589 	 * BOOTP does not necessarily have to be compiled into the kernel
590 	 * for an NFS root to work.  If we inherited the network
591 	 * configuration for PXEBOOT then pxe_setup_nfsdiskless() has figured
592 	 * out our interface for us and all we need to do is ifconfig the
593 	 * interface.  We only do this if the interface has not already been
594 	 * ifconfig'd by e.g. BOOTP.
595 	 */
596 	error = socreate(nd->myif.ifra_addr.sa_family, &so, SOCK_DGRAM, 0, td);
597 	if (error) {
598 		panic("nfs_mountroot: socreate(%04x): %d",
599 			nd->myif.ifra_addr.sa_family, error);
600 	}
601 
602 	error = ifioctl(so, SIOCAIFADDR, (caddr_t)&nd->myif, proc0.p_ucred);
603 	if (error)
604 		panic("nfs_mountroot: SIOCAIFADDR: %d", error);
605 
606 	soclose(so, FNONBLOCK);
607 
608 	/*
609 	 * If the gateway field is filled in, set it as the default route.
610 	 */
611 	if (nd->mygateway.sin_len != 0) {
612 		struct sockaddr_in mask, sin;
613 
614 		bzero((caddr_t)&mask, sizeof(mask));
615 		sin = mask;
616 		sin.sin_family = AF_INET;
617 		sin.sin_len = sizeof(sin);
618 		kprintf("nfs_mountroot: gateway %s\n",
619 			inet_ntoa(nd->mygateway.sin_addr));
620 		error = rtrequest_global(RTM_ADD, (struct sockaddr *)&sin,
621 					(struct sockaddr *)&nd->mygateway,
622 					(struct sockaddr *)&mask,
623 					RTF_UP | RTF_GATEWAY);
624 		if (error)
625 			kprintf("nfs_mountroot: unable to set gateway, error %d, continuing anyway\n", error);
626 	}
627 
628 	/*
629 	 * Create the rootfs mount point.
630 	 */
631 	nd->root_args.fh = nd->root_fh;
632 	nd->root_args.fhsize = nd->root_fhsize;
633 	l = ntohl(nd->root_saddr.sin_addr.s_addr);
634 	ksnprintf(buf, sizeof(buf), "%ld.%ld.%ld.%ld:%s",
635 		(l >> 24) & 0xff, (l >> 16) & 0xff,
636 		(l >>  8) & 0xff, (l >>  0) & 0xff,nd->root_hostnam);
637 	kprintf("NFS_ROOT: %s\n",buf);
638 	if ((error = nfs_mountdiskless(buf, "/", MNT_RDONLY,
639 	    &nd->root_saddr, &nd->root_args, td, &vp, &mp)) != 0) {
640 		mp->mnt_vfc->vfc_refcount--;
641 		crit_exit();
642 		return (error);
643 	}
644 
645 	swap_mp = NULL;
646 	if (nd->swap_nblks) {
647 
648 		/* Convert to DEV_BSIZE instead of Kilobyte */
649 		nd->swap_nblks *= 2;
650 
651 		/*
652 		 * Create a fake mount point just for the swap vnode so that the
653 		 * swap file can be on a different server from the rootfs.
654 		 */
655 		nd->swap_args.fh = nd->swap_fh;
656 		nd->swap_args.fhsize = nd->swap_fhsize;
657 		l = ntohl(nd->swap_saddr.sin_addr.s_addr);
658 		ksnprintf(buf, sizeof(buf), "%ld.%ld.%ld.%ld:%s",
659 			(l >> 24) & 0xff, (l >> 16) & 0xff,
660 			(l >>  8) & 0xff, (l >>  0) & 0xff,nd->swap_hostnam);
661 		kprintf("NFS SWAP: %s\n",buf);
662 		if ((error = nfs_mountdiskless(buf, "/swap", 0,
663 		    &nd->swap_saddr, &nd->swap_args, td, &vp, &swap_mp)) != 0) {
664 			crit_exit();
665 			return (error);
666 		}
667 		vfs_unbusy(swap_mp);
668 
669 		VTONFS(vp)->n_size = VTONFS(vp)->n_vattr.va_size =
670 				nd->swap_nblks * DEV_BSIZE ;
671 
672 		/*
673 		 * Since the swap file is not the root dir of a file system,
674 		 * hack it to a regular file.
675 		 */
676 		vclrflags(vp, VROOT);
677 		vref(vp);
678 		nfs_setvtype(vp, VREG);
679 		swaponvp(td, vp, nd->swap_nblks);
680 	}
681 
682 	mp->mnt_flag |= MNT_ROOTFS;
683 	vfs_unbusy(mp);
684 
685 	/*
686 	 * This is not really an nfs issue, but it is much easier to
687 	 * set hostname here and then let the "/etc/rc.xxx" files
688 	 * mount the right /var based upon its preset value.
689 	 */
690 	bcopy(nd->my_hostnam, hostname, MAXHOSTNAMELEN);
691 	hostname[MAXHOSTNAMELEN - 1] = '\0';
692 	for (i = 0; i < MAXHOSTNAMELEN; i++)
693 		if (hostname[i] == '\0')
694 			break;
695 	inittodr(ntohl(nd->root_time));
696 	crit_exit();
697 	return (0);
698 }
699 
700 /*
701  * Internal version of mount system call for diskless setup.
702  */
703 static int
704 nfs_mountdiskless(char *path, char *which, int mountflag,
705 	struct sockaddr_in *sin, struct nfs_args *args, struct thread *td,
706 	struct vnode **vpp, struct mount **mpp)
707 {
708 	struct mount *mp;
709 	struct sockaddr *nam;
710 	int didalloc = 0;
711 	int error;
712 
713 	mp = *mpp;
714 
715 	if (mp == NULL) {
716 		if ((error = vfs_rootmountalloc("nfs", path, &mp)) != 0) {
717 			kprintf("nfs_mountroot: NFS not configured");
718 			return (error);
719 		}
720 		didalloc = 1;
721 	}
722 	mp->mnt_kern_flag = 0;
723 	mp->mnt_flag = mountflag;
724 	nam = dup_sockaddr((struct sockaddr *)sin);
725 
726 #if defined(BOOTP) || defined(NFS_ROOT)
727 	if (args->fhsize == 0) {
728 		char *xpath = path;
729 
730 		kprintf("NFS_ROOT: No FH passed from loader, attempting mount rpc...");
731 		while (*xpath && *xpath != ':')
732 			++xpath;
733 		if (*xpath)
734 			++xpath;
735 		args->fhsize = 0;
736 		error = md_mount(sin, xpath, args->fh, &args->fhsize, args, td);
737 		if (error) {
738 			kprintf("failed error %d.\n", error);
739 			goto haderror;
740 		}
741 		kprintf("success!\n");
742 	}
743 #endif
744 
745 	if ((error = mountnfs(args, mp, nam, which, path, vpp)) != 0) {
746 #if defined(BOOTP) || defined(NFS_ROOT)
747 haderror:
748 #endif
749 		kprintf("nfs_mountroot: mount %s on %s: %d", path, which, error);
750 		mp->mnt_vfc->vfc_refcount--;
751 		vfs_unbusy(mp);
752 		if (didalloc)
753 			kfree(mp, M_MOUNT);
754 		FREE(nam, M_SONAME);
755 		return (error);
756 	}
757 	*mpp = mp;
758 	return (0);
759 }
760 
761 static void
762 nfs_decode_args(struct nfsmount *nmp, struct nfs_args *argp)
763 {
764 	int adjsock;
765 	int maxio;
766 
767 	crit_enter();
768 	/*
769 	 * Silently clear NFSMNT_NOCONN if it's a TCP mount, it makes
770 	 * no sense in that context.
771 	 */
772 	if (nmp->nm_sotype == SOCK_STREAM)
773 		nmp->nm_flag &= ~NFSMNT_NOCONN;
774 
775 	/* Also clear RDIRPLUS if not NFSv3, it crashes some servers */
776 	if ((argp->flags & NFSMNT_NFSV3) == 0)
777 		nmp->nm_flag &= ~NFSMNT_RDIRPLUS;
778 
779 	/*
780 	 * Re-bind if rsrvd port flag has changed
781 	 */
782 	adjsock = (nmp->nm_flag & NFSMNT_RESVPORT) !=
783 		  (argp->flags & NFSMNT_RESVPORT);
784 
785 	/* Update flags atomically.  Don't change the lock bits. */
786 	nmp->nm_flag = argp->flags | nmp->nm_flag;
787 	crit_exit();
788 
789 	if ((argp->flags & NFSMNT_TIMEO) && argp->timeo > 0) {
790 		nmp->nm_timeo = (argp->timeo * NFS_HZ + 5) / 10;
791 		if (nmp->nm_timeo < NFS_MINTIMEO)
792 			nmp->nm_timeo = NFS_MINTIMEO;
793 		else if (nmp->nm_timeo > NFS_MAXTIMEO)
794 			nmp->nm_timeo = NFS_MAXTIMEO;
795 	}
796 
797 	if ((argp->flags & NFSMNT_RETRANS) && argp->retrans > 1) {
798 		nmp->nm_retry = argp->retrans;
799 		if (nmp->nm_retry > NFS_MAXREXMIT)
800 			nmp->nm_retry = NFS_MAXREXMIT;
801 	}
802 
803 	/*
804 	 * These parameters effect the buffer cache and cannot be changed
805 	 * once we've successfully mounted.
806 	 */
807 	if ((nmp->nm_state & NFSSTA_GOTFSINFO) == 0) {
808 		maxio = nfs_iosize(argp->flags & NFSMNT_NFSV3, nmp->nm_sotype);
809 
810 		if ((argp->flags & NFSMNT_WSIZE) && argp->wsize > 0) {
811 			nmp->nm_wsize = argp->wsize;
812 			/* Round down to multiple of blocksize */
813 			nmp->nm_wsize &= ~(NFS_FABLKSIZE - 1);
814 			if (nmp->nm_wsize <= 0)
815 				nmp->nm_wsize = NFS_FABLKSIZE;
816 		}
817 		if (nmp->nm_wsize > maxio)
818 			nmp->nm_wsize = maxio;
819 		if (nmp->nm_wsize > MAXBSIZE)
820 			nmp->nm_wsize = MAXBSIZE;
821 
822 		if ((argp->flags & NFSMNT_RSIZE) && argp->rsize > 0) {
823 			nmp->nm_rsize = argp->rsize;
824 			/* Round down to multiple of blocksize */
825 			nmp->nm_rsize &= ~(NFS_FABLKSIZE - 1);
826 			if (nmp->nm_rsize <= 0)
827 				nmp->nm_rsize = NFS_FABLKSIZE;
828 		}
829 		if (nmp->nm_rsize > maxio)
830 			nmp->nm_rsize = maxio;
831 		if (nmp->nm_rsize > MAXBSIZE)
832 			nmp->nm_rsize = MAXBSIZE;
833 
834 		if ((argp->flags & NFSMNT_READDIRSIZE) &&
835 		    argp->readdirsize > 0) {
836 			nmp->nm_readdirsize = argp->readdirsize;
837 		}
838 		if (nmp->nm_readdirsize > maxio)
839 			nmp->nm_readdirsize = maxio;
840 		if (nmp->nm_readdirsize > nmp->nm_rsize)
841 			nmp->nm_readdirsize = nmp->nm_rsize;
842 	}
843 
844 	if ((argp->flags & NFSMNT_ACREGMIN) && argp->acregmin >= 0)
845 		nmp->nm_acregmin = argp->acregmin;
846 	else
847 		nmp->nm_acregmin = NFS_MINATTRTIMO;
848 	if ((argp->flags & NFSMNT_ACREGMAX) && argp->acregmax >= 0)
849 		nmp->nm_acregmax = argp->acregmax;
850 	else
851 		nmp->nm_acregmax = NFS_MAXATTRTIMO;
852 	if ((argp->flags & NFSMNT_ACDIRMIN) && argp->acdirmin >= 0)
853 		nmp->nm_acdirmin = argp->acdirmin;
854 	else
855 		nmp->nm_acdirmin = NFS_MINDIRATTRTIMO;
856 	if ((argp->flags & NFSMNT_ACDIRMAX) && argp->acdirmax >= 0)
857 		nmp->nm_acdirmax = argp->acdirmax;
858 	else
859 		nmp->nm_acdirmax = NFS_MAXDIRATTRTIMO;
860 	if (nmp->nm_acdirmin > nmp->nm_acdirmax)
861 		nmp->nm_acdirmin = nmp->nm_acdirmax;
862 	if (nmp->nm_acregmin > nmp->nm_acregmax)
863 		nmp->nm_acregmin = nmp->nm_acregmax;
864 
865 	if ((argp->flags & NFSMNT_MAXGRPS) && argp->maxgrouplist >= 0) {
866 		if (argp->maxgrouplist <= NFS_MAXGRPS)
867 			nmp->nm_numgrps = argp->maxgrouplist;
868 		else
869 			nmp->nm_numgrps = NFS_MAXGRPS;
870 	}
871 	if ((argp->flags & NFSMNT_READAHEAD) && argp->readahead >= 0) {
872 		if (argp->readahead <= NFS_MAXRAHEAD)
873 			nmp->nm_readahead = argp->readahead;
874 		else
875 			nmp->nm_readahead = NFS_MAXRAHEAD;
876 	}
877 	if ((argp->flags & NFSMNT_DEADTHRESH) && argp->deadthresh >= 1) {
878 		if (argp->deadthresh <= NFS_NEVERDEAD)
879 			nmp->nm_deadthresh = argp->deadthresh;
880 		else
881 			nmp->nm_deadthresh = NFS_NEVERDEAD;
882 	}
883 
884 	if (nmp->nm_so && adjsock) {
885 		nfs_safedisconnect(nmp);
886 		if (nmp->nm_sotype == SOCK_DGRAM)
887 			while (nfs_connect(nmp, NULL)) {
888 				kprintf("nfs_args: retrying connect\n");
889 				(void) tsleep((caddr_t)&lbolt, 0, "nfscon", 0);
890 			}
891 	}
892 }
893 
894 /*
895  * VFS Operations.
896  *
897  * mount system call
898  * It seems a bit dumb to copyinstr() the host and path here and then
899  * bcopy() them in mountnfs(), but I wanted to detect errors before
900  * doing the sockargs() call because sockargs() allocates an mbuf and
901  * an error after that means that I have to release the mbuf.
902  */
903 /* ARGSUSED */
904 static int
905 nfs_mount(struct mount *mp, char *path, caddr_t data, struct ucred *cred)
906 {
907 	int error;
908 	struct nfs_args args;
909 	struct sockaddr *nam;
910 	struct vnode *vp;
911 	char pth[MNAMELEN], hst[MNAMELEN];
912 	size_t len;
913 	u_char nfh[NFSX_V3FHMAX];
914 
915 	if (path == NULL) {
916 		nfs_mountroot(mp);
917 		return (0);
918 	}
919 	error = copyin(data, (caddr_t)&args, sizeof (struct nfs_args));
920 	if (error)
921 		return (error);
922 	if (args.version != NFS_ARGSVERSION) {
923 #ifdef COMPAT_PRELITE2
924 		/*
925 		 * If the argument version is unknown, then assume the
926 		 * caller is a pre-lite2 4.4BSD client and convert its
927 		 * arguments.
928 		 */
929 		struct onfs_args oargs;
930 		error = copyin(data, (caddr_t)&oargs, sizeof (struct onfs_args));
931 		if (error)
932 			return (error);
933 		nfs_convert_oargs(&args,&oargs);
934 #else /* !COMPAT_PRELITE2 */
935 		return (EPROGMISMATCH);
936 #endif /* COMPAT_PRELITE2 */
937 	}
938 	if (mp->mnt_flag & MNT_UPDATE) {
939 		struct nfsmount *nmp = VFSTONFS(mp);
940 
941 		if (nmp == NULL)
942 			return (EIO);
943 		/*
944 		 * When doing an update, we can't change from or to
945 		 * v3, or change cookie translation, or rsize or wsize.
946 		 */
947 		args.flags &= ~(NFSMNT_NFSV3 | NFSMNT_RSIZE | NFSMNT_WSIZE);
948 		args.flags |= nmp->nm_flag & (NFSMNT_NFSV3);
949 		nfs_decode_args(nmp, &args);
950 		return (0);
951 	}
952 
953 	/*
954 	 * Make the nfs_ip_paranoia sysctl serve as the default connection
955 	 * or no-connection mode for those protocols that support
956 	 * no-connection mode (the flag will be cleared later for protocols
957 	 * that do not support no-connection mode).  This will allow a client
958 	 * to receive replies from a different IP then the request was
959 	 * sent to.  Note: default value for nfs_ip_paranoia is 1 (paranoid),
960 	 * not 0.
961 	 */
962 	if (nfs_ip_paranoia == 0)
963 		args.flags |= NFSMNT_NOCONN;
964 	if (args.fhsize < 0 || args.fhsize > NFSX_V3FHMAX)
965 		return (EINVAL);
966 	error = copyin((caddr_t)args.fh, (caddr_t)nfh, args.fhsize);
967 	if (error)
968 		return (error);
969 	error = copyinstr(path, pth, MNAMELEN-1, &len);
970 	if (error)
971 		return (error);
972 	bzero(&pth[len], MNAMELEN - len);
973 	error = copyinstr(args.hostname, hst, MNAMELEN-1, &len);
974 	if (error)
975 		return (error);
976 	bzero(&hst[len], MNAMELEN - len);
977 	/* sockargs() call must be after above copyin() calls */
978 	error = getsockaddr(&nam, (caddr_t)args.addr, args.addrlen);
979 	if (error)
980 		return (error);
981 	args.fh = nfh;
982 	error = mountnfs(&args, mp, nam, pth, hst, &vp);
983 	return (error);
984 }
985 
986 /*
987  * Common code for mount and mountroot
988  */
989 static int
990 mountnfs(struct nfs_args *argp, struct mount *mp, struct sockaddr *nam,
991 	char *pth, char *hst, struct vnode **vpp)
992 {
993 	struct nfsmount *nmp;
994 	struct nfsnode *np;
995 	int error;
996 	int rxcpu;
997 	int txcpu;
998 
999 	if (mp->mnt_flag & MNT_UPDATE) {
1000 		nmp = VFSTONFS(mp);
1001 		/* update paths, file handles, etc, here	XXX */
1002 		FREE(nam, M_SONAME);
1003 		return (0);
1004 	} else {
1005 		nmp = zalloc(nfsmount_zone);
1006 		bzero((caddr_t)nmp, sizeof (struct nfsmount));
1007 		mtx_init(&nmp->nm_rxlock);
1008 		mtx_init(&nmp->nm_txlock);
1009 		TAILQ_INIT(&nmp->nm_uidlruhead);
1010 		TAILQ_INIT(&nmp->nm_bioq);
1011 		TAILQ_INIT(&nmp->nm_reqq);
1012 		TAILQ_INIT(&nmp->nm_reqtxq);
1013 		TAILQ_INIT(&nmp->nm_reqrxq);
1014 		mp->mnt_data = (qaddr_t)nmp;
1015 		lwkt_token_init(&nmp->nm_token, 1, "nfs_token");
1016 	}
1017 	vfs_getnewfsid(mp);
1018 	nmp->nm_mountp = mp;
1019 	mp->mnt_kern_flag |= MNTK_ALL_MPSAFE;
1020 
1021 	lwkt_gettoken(&nmp->nm_token);
1022 
1023 	/*
1024 	 * V2 can only handle 32 bit filesizes.  A 4GB-1 limit may be too
1025 	 * high, depending on whether we end up with negative offsets in
1026 	 * the client or server somewhere.  2GB-1 may be safer.
1027 	 *
1028 	 * For V3, nfs_fsinfo will adjust this as necessary.  Assume maximum
1029 	 * that we can handle until we find out otherwise.
1030 	 * XXX Our "safe" limit on the client is what we can store in our
1031 	 * buffer cache using signed(!) block numbers.
1032 	 */
1033 	if ((argp->flags & NFSMNT_NFSV3) == 0)
1034 		nmp->nm_maxfilesize = 0xffffffffLL;
1035 	else
1036 		nmp->nm_maxfilesize = (u_int64_t)0x80000000 * DEV_BSIZE - 1;
1037 
1038 	nmp->nm_timeo = NFS_TIMEO;
1039 	nmp->nm_retry = NFS_RETRANS;
1040 	nmp->nm_wsize = nfs_iosize(argp->flags & NFSMNT_NFSV3, argp->sotype);
1041 	nmp->nm_rsize = nmp->nm_wsize;
1042 	nmp->nm_readdirsize = NFS_READDIRSIZE;
1043 	nmp->nm_numgrps = NFS_MAXGRPS;
1044 	nmp->nm_readahead = NFS_DEFRAHEAD;
1045 	nmp->nm_deadthresh = NFS_DEADTHRESH;
1046 	nmp->nm_fhsize = argp->fhsize;
1047 	bcopy((caddr_t)argp->fh, (caddr_t)nmp->nm_fh, argp->fhsize);
1048 	bcopy(hst, mp->mnt_stat.f_mntfromname, MNAMELEN);
1049 	nmp->nm_nam = nam;
1050 	/* Set up the sockets and per-host congestion */
1051 	nmp->nm_sotype = argp->sotype;
1052 	nmp->nm_soproto = argp->proto;
1053 	nmp->nm_cred = crhold(proc0.p_ucred);
1054 
1055 	nfs_decode_args(nmp, argp);
1056 
1057 	/*
1058 	 * For Connection based sockets (TCP,...) defer the connect until
1059 	 * the first request, in case the server is not responding.
1060 	 */
1061 	if (nmp->nm_sotype == SOCK_DGRAM &&
1062 		(error = nfs_connect(nmp, NULL)))
1063 		goto bad;
1064 
1065 	/*
1066 	 * This is silly, but it has to be set so that vinifod() works.
1067 	 * We do not want to do an nfs_statfs() here since we can get
1068 	 * stuck on a dead server and we are holding a lock on the mount
1069 	 * point.
1070 	 */
1071 	mp->mnt_stat.f_iosize =
1072 		nfs_iosize(nmp->nm_flag & NFSMNT_NFSV3, nmp->nm_sotype);
1073 
1074 	/*
1075 	 * Install vop_ops for our vnops
1076 	 */
1077 	vfs_add_vnodeops(mp, &nfsv2_vnode_vops, &mp->mnt_vn_norm_ops);
1078 	vfs_add_vnodeops(mp, &nfsv2_spec_vops, &mp->mnt_vn_spec_ops);
1079 	vfs_add_vnodeops(mp, &nfsv2_fifo_vops, &mp->mnt_vn_fifo_ops);
1080 
1081 	/*
1082 	 * A reference count is needed on the nfsnode representing the
1083 	 * remote root.  If this object is not persistent, then backward
1084 	 * traversals of the mount point (i.e. "..") will not work if
1085 	 * the nfsnode gets flushed out of the cache. Ufs does not have
1086 	 * this problem, because one can identify root inodes by their
1087 	 * number == ROOTINO (2).
1088 	 */
1089 	error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
1090 	if (error)
1091 		goto bad;
1092 	*vpp = NFSTOV(np);
1093 
1094 	/*
1095 	 * Retrieval of mountpoint attributes is delayed until nfs_rot
1096 	 * or nfs_statfs are first called.  This will happen either when
1097 	 * we first traverse the mount point or if somebody does a df(1).
1098 	 *
1099 	 * NFSSTA_GOTFSINFO is used to flag if we have successfully
1100 	 * retrieved mountpoint attributes.  In the case of NFSv3 we
1101 	 * also flag static fsinfo.
1102 	 */
1103 	if (*vpp != NULL)
1104 		(*vpp)->v_type = VNON;
1105 
1106 	/*
1107 	 * Lose the lock but keep the ref.
1108 	 */
1109 	vn_unlock(*vpp);
1110 	lwkt_gettoken(&nfs_token);
1111 	TAILQ_INSERT_TAIL(&nfs_mountq, nmp, nm_entry);
1112 	lwkt_reltoken(&nfs_token);
1113 
1114 #ifdef SMP
1115 	switch(ncpus) {
1116 	case 0:
1117 	case 1:
1118 		rxcpu = 0;
1119 		txcpu = 0;
1120 		break;
1121 	case 2:
1122 		rxcpu = 0;
1123 		txcpu = 1;
1124 		break;
1125 	default:
1126 		rxcpu = 1;
1127 		txcpu = 2;
1128 		break;
1129 	}
1130 #else
1131 	rxcpu = 0;
1132 	txcpu = 0;
1133 #endif
1134 
1135 	/*
1136 	 * Start the reader and writer threads.
1137 	 */
1138 	lwkt_create(nfssvc_iod_reader, nmp, &nmp->nm_rxthread,
1139 		    NULL, 0, rxcpu, "nfsiod_rx");
1140 	lwkt_create(nfssvc_iod_writer, nmp, &nmp->nm_txthread,
1141 		    NULL, 0, txcpu, "nfsiod_tx");
1142 	lwkt_reltoken(&nmp->nm_token);
1143 	return (0);
1144 bad:
1145 	nfs_disconnect(nmp);
1146 	lwkt_reltoken(&nmp->nm_token);
1147 	nfs_free_mount(nmp);
1148 	return (error);
1149 }
1150 
1151 /*
1152  * unmount system call
1153  */
1154 static int
1155 nfs_unmount(struct mount *mp, int mntflags)
1156 {
1157 	struct nfsmount *nmp;
1158 	int error, flags = 0;
1159 
1160 	nmp = VFSTONFS(mp);
1161 	lwkt_gettoken(&nmp->nm_token);
1162 	if (mntflags & MNT_FORCE) {
1163 		flags |= FORCECLOSE;
1164 		nmp->nm_flag |= NFSMNT_FORCE;
1165 	}
1166 
1167 	/*
1168 	 * Goes something like this..
1169 	 * - Call vflush() to clear out vnodes for this file system
1170 	 * - Close the socket
1171 	 * - Free up the data structures
1172 	 */
1173 	/* In the forced case, cancel any outstanding requests. */
1174 	if (flags & FORCECLOSE) {
1175 		error = nfs_nmcancelreqs(nmp);
1176 		if (error) {
1177 			kprintf("NFS: %s: Unable to cancel all requests\n",
1178 				mp->mnt_stat.f_mntfromname);
1179 			/* continue anyway */
1180 		}
1181 	}
1182 
1183 	/*
1184 	 * Must handshake with nfs_clientd() if it is active. XXX
1185 	 */
1186 	nmp->nm_state |= NFSSTA_DISMINPROG;
1187 
1188 	/*
1189 	 * We hold 1 extra ref on the root vnode; see comment in mountnfs().
1190 	 *
1191 	 * If this doesn't work and we are doing a forced unmount we continue
1192 	 * anyway.
1193 	 */
1194 	error = vflush(mp, 1, flags);
1195 	if (error) {
1196 		nmp->nm_state &= ~NFSSTA_DISMINPROG;
1197 		if ((flags & FORCECLOSE) == 0) {
1198 			lwkt_reltoken(&nmp->nm_token);
1199 			return (error);
1200 		}
1201 	}
1202 
1203 	/*
1204 	 * We are now committed to the unmount.
1205 	 * For NQNFS, let the server daemon free the nfsmount structure.
1206 	 */
1207 	if (nmp->nm_flag & NFSMNT_KERB)
1208 		nmp->nm_state |= NFSSTA_DISMNT;
1209 	nfssvc_iod_stop1(nmp);
1210 	nfs_disconnect(nmp);
1211 	nfssvc_iod_stop2(nmp);
1212 
1213 	lwkt_gettoken(&nfs_token);
1214 	TAILQ_REMOVE(&nfs_mountq, nmp, nm_entry);
1215 	lwkt_reltoken(&nfs_token);
1216 
1217 	lwkt_reltoken(&nmp->nm_token);
1218 
1219 	if ((nmp->nm_flag & NFSMNT_KERB) == 0) {
1220 		nfs_free_mount(nmp);
1221 	}
1222 	return (0);
1223 }
1224 
1225 void
1226 nfs_free_mount(struct nfsmount *nmp)
1227 {
1228 	if (nmp->nm_cred)  {
1229 		crfree(nmp->nm_cred);
1230 		nmp->nm_cred = NULL;
1231 	}
1232 	if (nmp->nm_nam) {
1233 		FREE(nmp->nm_nam, M_SONAME);
1234 		nmp->nm_nam = NULL;
1235 	}
1236 	zfree(nfsmount_zone, nmp);
1237 }
1238 
1239 /*
1240  * Return root of a filesystem
1241  */
1242 static int
1243 nfs_root(struct mount *mp, struct vnode **vpp)
1244 {
1245 	struct vnode *vp;
1246 	struct nfsmount *nmp;
1247 	struct vattr attrs;
1248 	struct nfsnode *np;
1249 	int error;
1250 
1251 	nmp = VFSTONFS(mp);
1252 	lwkt_gettoken(&nmp->nm_token);
1253 	error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
1254 	if (error) {
1255 		lwkt_reltoken(&nmp->nm_token);
1256 		return (error);
1257 	}
1258 	vp = NFSTOV(np);
1259 
1260 	/*
1261 	 * Get transfer parameters and root vnode attributes
1262 	 *
1263 	 * NOTE: nfs_fsinfo() is expected to override the default
1264 	 *	 f_iosize we set.
1265 	 */
1266 	if ((nmp->nm_state & NFSSTA_GOTFSINFO) == 0) {
1267 	    if (nmp->nm_flag & NFSMNT_NFSV3) {
1268 		mp->mnt_stat.f_iosize = nfs_iosize(1, nmp->nm_sotype);
1269 		error = nfs_fsinfo(nmp, vp, curthread);
1270 	    } else {
1271 		if ((error = VOP_GETATTR(vp, &attrs)) == 0)
1272 			nmp->nm_state |= NFSSTA_GOTFSINFO;
1273 
1274 	    }
1275 	} else {
1276 	    /*
1277 	     * The root vnode is usually cached by the namecache so do not
1278 	     * try to avoid going over the wire even if we have previous
1279 	     * information cached.  A stale NFS mount can loop
1280 	     * forever resolving the root vnode if we return no-error when
1281 	     * there is in fact an error.
1282 	     */
1283 	    np->n_attrstamp = 0;
1284 	    error = VOP_GETATTR(vp, &attrs);
1285 	}
1286 	if (vp->v_type == VNON)
1287 	    nfs_setvtype(vp, VDIR);
1288 	vsetflags(vp, VROOT);
1289 	if (error)
1290 		vput(vp);
1291 	else
1292 		*vpp = vp;
1293 	lwkt_reltoken(&nmp->nm_token);
1294 	return (error);
1295 }
1296 
1297 struct scaninfo {
1298 	int rescan;
1299 	int waitfor;
1300 	int allerror;
1301 };
1302 
1303 static int nfs_sync_scan1(struct mount *mp, struct vnode *vp, void *data);
1304 static int nfs_sync_scan2(struct mount *mp, struct vnode *vp, void *data);
1305 
1306 /*
1307  * Flush out the buffer cache
1308  */
1309 /* ARGSUSED */
1310 static int
1311 nfs_sync(struct mount *mp, int waitfor)
1312 {
1313 	struct nfsmount *nmp = VFSTONFS(mp);
1314 	struct scaninfo scaninfo;
1315 	int error;
1316 
1317 	scaninfo.rescan = 1;
1318 	scaninfo.waitfor = waitfor;
1319 	scaninfo.allerror = 0;
1320 
1321 	/*
1322 	 * Force stale buffer cache information to be flushed.
1323 	 */
1324 	lwkt_gettoken(&nmp->nm_token);
1325 	error = 0;
1326 	while (error == 0 && scaninfo.rescan) {
1327 		scaninfo.rescan = 0;
1328 		error = vmntvnodescan(mp, VMSC_GETVP, nfs_sync_scan1,
1329 					nfs_sync_scan2, &scaninfo);
1330 	}
1331 	lwkt_reltoken(&nmp->nm_token);
1332 	return(error);
1333 }
1334 
1335 static int
1336 nfs_sync_scan1(struct mount *mp, struct vnode *vp, void *data)
1337 {
1338     struct scaninfo *info = data;
1339 
1340     if (vn_islocked(vp) || RB_EMPTY(&vp->v_rbdirty_tree))
1341 	return(-1);
1342     if (info->waitfor == MNT_LAZY)
1343 	return(-1);
1344     return(0);
1345 }
1346 
1347 static int
1348 nfs_sync_scan2(struct mount *mp, struct vnode *vp, void *data)
1349 {
1350     struct scaninfo *info = data;
1351     int error;
1352 
1353     error = VOP_FSYNC(vp, info->waitfor, 0);
1354     if (error)
1355 	info->allerror = error;
1356     return(0);
1357 }
1358 
1359