xref: /netbsd-src/sys/nfs/nfs_vfsops.c (revision 154bfe8e089c1a0a4e9ed8414f08d3da90949162)
1 /*	$NetBSD: nfs_vfsops.c,v 1.241 2020/04/13 19:23:20 ad Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993, 1995
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Rick Macklem at The University of Guelph.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)nfs_vfsops.c	8.12 (Berkeley) 5/20/95
35  */
36 
37 #include <sys/cdefs.h>
38 __KERNEL_RCSID(0, "$NetBSD: nfs_vfsops.c,v 1.241 2020/04/13 19:23:20 ad Exp $");
39 
40 #if defined(_KERNEL_OPT)
41 #include "opt_nfs.h"
42 #endif
43 
44 #include <sys/param.h>
45 #include <sys/ioctl.h>
46 #include <sys/signal.h>
47 #include <sys/proc.h>
48 #include <sys/namei.h>
49 #include <sys/device.h>
50 #include <sys/vnode.h>
51 #include <sys/kernel.h>
52 #include <sys/mount.h>
53 #include <sys/buf.h>
54 #include <sys/mbuf.h>
55 #include <sys/dirent.h>
56 #include <sys/socket.h>
57 #include <sys/socketvar.h>
58 #include <sys/sysctl.h>
59 #include <sys/systm.h>
60 #include <sys/timetc.h>
61 #include <sys/kauth.h>
62 #include <sys/module.h>
63 
64 #include <net/if.h>
65 #include <net/route.h>
66 #include <netinet/in.h>
67 
68 #include <nfs/rpcv2.h>
69 #include <nfs/nfsproto.h>
70 #include <nfs/nfsnode.h>
71 #include <nfs/nfs.h>
72 #include <nfs/nfsmount.h>
73 #include <nfs/xdr_subs.h>
74 #include <nfs/nfsm_subs.h>
75 #include <nfs/nfsdiskless.h>
76 #include <nfs/nfs_var.h>
77 
78 MODULE(MODULE_CLASS_VFS, nfs, NULL);
79 
80 extern struct nfsstats nfsstats;
81 extern int nfs_ticks;
82 
83 /*
84  * keep a count of the nfs mounts to generate ficticious drive names
85  * for the per drive stats.
86  */
87 unsigned int nfs_mount_count = 0;
88 
89 int nfs_commitsize;
90 
91 /*
92  * nfs vfs operations.
93  */
94 
95 extern const struct vnodeopv_desc nfsv2_vnodeop_opv_desc;
96 extern const struct vnodeopv_desc spec_nfsv2nodeop_opv_desc;
97 extern const struct vnodeopv_desc fifo_nfsv2nodeop_opv_desc;
98 
99 const struct vnodeopv_desc * const nfs_vnodeopv_descs[] = {
100 	&nfsv2_vnodeop_opv_desc,
101 	&spec_nfsv2nodeop_opv_desc,
102 	&fifo_nfsv2nodeop_opv_desc,
103 	NULL,
104 };
105 
106 struct vfsops nfs_vfsops = {
107 	.vfs_name = MOUNT_NFS,
108 	.vfs_min_mount_data = sizeof (struct nfs_args),
109 	.vfs_mount = nfs_mount,
110 	.vfs_start = nfs_start,
111 	.vfs_unmount = nfs_unmount,
112 	.vfs_root = nfs_root,
113 	.vfs_quotactl = (void *)eopnotsupp,
114 	.vfs_statvfs = nfs_statvfs,
115 	.vfs_sync = nfs_sync,
116 	.vfs_loadvnode = nfs_loadvnode,
117 	.vfs_vget = nfs_vget,
118 	.vfs_fhtovp = nfs_fhtovp,
119 	.vfs_vptofh = nfs_vptofh,
120 	.vfs_init = nfs_vfs_init,
121 	.vfs_done = nfs_vfs_done,
122 	.vfs_mountroot = nfs_mountroot,
123 	.vfs_snapshot = (void *)eopnotsupp,
124 	.vfs_extattrctl = vfs_stdextattrctl,
125 	.vfs_suspendctl = genfs_suspendctl,
126 	.vfs_renamelock_enter = genfs_renamelock_enter,
127 	.vfs_renamelock_exit = genfs_renamelock_exit,
128 	.vfs_fsync = (void *)eopnotsupp,
129 	.vfs_opv_descs = nfs_vnodeopv_descs
130 };
131 
132 extern u_int32_t nfs_procids[NFS_NPROCS];
133 extern u_int32_t nfs_prog, nfs_vers;
134 
135 static int nfs_mount_diskless(struct nfs_dlmount *, const char *,
136     struct mount **, struct vnode **, struct lwp *);
137 
138 static int
139 nfs_modcmd(modcmd_t cmd, void *arg)
140 {
141 	int error;
142 
143 	switch (cmd) {
144 	case MODULE_CMD_INIT:
145 		error = vfs_attach(&nfs_vfsops);
146 		return error;
147 	case MODULE_CMD_FINI:
148 		error = vfs_detach(&nfs_vfsops);
149 		return error;
150 	default:
151 		return ENOTTY;
152 	}
153 }
154 
155 /*
156  * nfs statvfs call
157  */
158 int
159 nfs_statvfs(struct mount *mp, struct statvfs *sbp)
160 {
161 	struct lwp *l = curlwp;
162 	struct vnode *vp;
163 	struct nfs_statfs *sfp;
164 	char *cp;
165 	u_int32_t *tl;
166 	int32_t t1, t2;
167 	char *bpos, *dpos, *cp2;
168 	struct nfsmount *nmp = VFSTONFS(mp);
169 	int error = 0, retattr;
170 #ifdef NFS_V2_ONLY
171 	const int v3 = 0;
172 #else
173 	int v3 = (nmp->nm_flag & NFSMNT_NFSV3);
174 #endif
175 	struct mbuf *mreq, *mrep = NULL, *md, *mb;
176 	kauth_cred_t cred;
177 	u_quad_t tquad;
178 	struct nfsnode *np;
179 
180 #ifndef nolint
181 	sfp = (struct nfs_statfs *)0;
182 #endif
183 	vp = nmp->nm_vnode;
184 	np = VTONFS(vp);
185 	cred = kauth_cred_alloc();
186 #ifndef NFS_V2_ONLY
187 	if (v3 && (nmp->nm_iflag & NFSMNT_GOTFSINFO) == 0)
188 		(void)nfs_fsinfo(nmp, vp, cred, l);
189 #endif
190 	nfsstats.rpccnt[NFSPROC_FSSTAT]++;
191 	nfsm_reqhead(np, NFSPROC_FSSTAT, NFSX_FH(v3));
192 	nfsm_fhtom(np, v3);
193 	nfsm_request(np, NFSPROC_FSSTAT, l, cred);
194 	if (v3)
195 		nfsm_postop_attr(vp, retattr, 0);
196 	if (error) {
197 		if (mrep != NULL) {
198 			if (mrep->m_next != NULL)
199 				printf("nfs_vfsops: nfs_statvfs would lose buffers\n");
200 			m_freem(mrep);
201 		}
202 		goto nfsmout;
203 	}
204 	nfsm_dissect(sfp, struct nfs_statfs *, NFSX_STATFS(v3));
205 	sbp->f_flag = nmp->nm_flag;
206 	sbp->f_iosize = uimin(nmp->nm_rsize, nmp->nm_wsize);
207 	if (v3) {
208 		sbp->f_frsize = sbp->f_bsize = NFS_FABLKSIZE;
209 		tquad = fxdr_hyper(&sfp->sf_tbytes);
210 		sbp->f_blocks = ((quad_t)tquad / (quad_t)NFS_FABLKSIZE);
211 		tquad = fxdr_hyper(&sfp->sf_fbytes);
212 		sbp->f_bfree = ((quad_t)tquad / (quad_t)NFS_FABLKSIZE);
213 		tquad = fxdr_hyper(&sfp->sf_abytes);
214 		tquad = ((quad_t)tquad / (quad_t)NFS_FABLKSIZE);
215 		sbp->f_bresvd = sbp->f_bfree - tquad;
216 		sbp->f_bavail = tquad;
217 		/* Handle older NFS servers returning negative values */
218 		if ((quad_t)sbp->f_bavail < 0)
219 			sbp->f_bavail = 0;
220 		tquad = fxdr_hyper(&sfp->sf_tfiles);
221 		sbp->f_files = tquad;
222 		tquad = fxdr_hyper(&sfp->sf_ffiles);
223 		sbp->f_ffree = tquad;
224 		sbp->f_favail = tquad;
225 		sbp->f_fresvd = 0;
226 		sbp->f_namemax = NFS_MAXNAMLEN;
227 	} else {
228 		sbp->f_bsize = NFS_FABLKSIZE;
229 		sbp->f_frsize = fxdr_unsigned(int32_t, sfp->sf_bsize);
230 		sbp->f_blocks = fxdr_unsigned(int32_t, sfp->sf_blocks);
231 		sbp->f_bfree = fxdr_unsigned(int32_t, sfp->sf_bfree);
232 		sbp->f_bavail = fxdr_unsigned(int32_t, sfp->sf_bavail);
233 		sbp->f_fresvd = 0;
234 		sbp->f_files = 0;
235 		sbp->f_ffree = 0;
236 		sbp->f_favail = 0;
237 		sbp->f_fresvd = 0;
238 		sbp->f_namemax = NFS_MAXNAMLEN;
239 	}
240 	copy_statvfs_info(sbp, mp);
241 	nfsm_reqdone;
242 	kauth_cred_free(cred);
243 	return (error);
244 }
245 
246 #ifndef NFS_V2_ONLY
247 /*
248  * nfs version 3 fsinfo rpc call
249  */
250 int
251 nfs_fsinfo(struct nfsmount *nmp, struct vnode *vp, kauth_cred_t cred, struct lwp *l)
252 {
253 	struct nfsv3_fsinfo *fsp;
254 	char *cp;
255 	int32_t t1, t2;
256 	u_int32_t *tl, pref, xmax;
257 	char *bpos, *dpos, *cp2;
258 	int error = 0, retattr;
259 	struct mbuf *mreq, *mrep, *md, *mb;
260 	u_int64_t maxfsize;
261 	struct nfsnode *np = VTONFS(vp);
262 
263 	nfsstats.rpccnt[NFSPROC_FSINFO]++;
264 	nfsm_reqhead(np, NFSPROC_FSINFO, NFSX_FH(1));
265 	nfsm_fhtom(np, 1);
266 	nfsm_request(np, NFSPROC_FSINFO, l, cred);
267 	nfsm_postop_attr(vp, retattr, 0);
268 	if (!error) {
269 		nfsm_dissect(fsp, struct nfsv3_fsinfo *, NFSX_V3FSINFO);
270 		pref = fxdr_unsigned(u_int32_t, fsp->fs_wtpref);
271 		if ((nmp->nm_flag & NFSMNT_WSIZE) == 0 &&
272 		    pref < nmp->nm_wsize && pref >= NFS_FABLKSIZE)
273 			nmp->nm_wsize = (pref + NFS_FABLKSIZE - 1) &
274 				~(NFS_FABLKSIZE - 1);
275 		xmax = fxdr_unsigned(u_int32_t, fsp->fs_wtmax);
276 		if (xmax < nmp->nm_wsize && xmax > 0) {
277 			nmp->nm_wsize = xmax & ~(NFS_FABLKSIZE - 1);
278 			if (nmp->nm_wsize == 0)
279 				nmp->nm_wsize = xmax;
280 		}
281 		pref = fxdr_unsigned(u_int32_t, fsp->fs_rtpref);
282 		if ((nmp->nm_flag & NFSMNT_RSIZE) == 0 &&
283 		    pref < nmp->nm_rsize && pref >= NFS_FABLKSIZE)
284 			nmp->nm_rsize = (pref + NFS_FABLKSIZE - 1) &
285 				~(NFS_FABLKSIZE - 1);
286 		xmax = fxdr_unsigned(u_int32_t, fsp->fs_rtmax);
287 		if (xmax < nmp->nm_rsize && xmax > 0) {
288 			nmp->nm_rsize = xmax & ~(NFS_FABLKSIZE - 1);
289 			if (nmp->nm_rsize == 0)
290 				nmp->nm_rsize = xmax;
291 		}
292 		pref = fxdr_unsigned(u_int32_t, fsp->fs_dtpref);
293 		if (pref < nmp->nm_readdirsize && pref >= NFS_DIRFRAGSIZ)
294 			nmp->nm_readdirsize = (pref + NFS_DIRFRAGSIZ - 1) &
295 				~(NFS_DIRFRAGSIZ - 1);
296 		if (xmax < nmp->nm_readdirsize && xmax > 0) {
297 			nmp->nm_readdirsize = xmax & ~(NFS_DIRFRAGSIZ - 1);
298 			if (nmp->nm_readdirsize == 0)
299 				nmp->nm_readdirsize = xmax;
300 		}
301 		/* XXX */
302 		nmp->nm_maxfilesize = (u_int64_t)0x80000000 * DEV_BSIZE - 1;
303 		maxfsize = fxdr_hyper(&fsp->fs_maxfilesize);
304 		if (maxfsize > 0 && maxfsize < nmp->nm_maxfilesize)
305 			nmp->nm_maxfilesize = maxfsize;
306 		nmp->nm_mountp->mnt_fs_bshift =
307 		    ffs(MIN(nmp->nm_rsize, nmp->nm_wsize)) - 1;
308 		nmp->nm_iflag |= NFSMNT_GOTFSINFO;
309 	}
310 	nfsm_reqdone;
311 	return (error);
312 }
313 #endif
314 
315 /*
316  * Mount a remote root fs via. NFS.  It goes like this:
317  * - Call nfs_boot_init() to fill in the nfs_diskless struct
318  * - build the rootfs mount point and call mountnfs() to do the rest.
319  */
320 int
321 nfs_mountroot(void)
322 {
323 	struct timespec ts;
324 	struct nfs_diskless *nd;
325 	struct vattr attr;
326 	struct mount *mp;
327 	struct vnode *vp;
328 	struct lwp *l;
329 	long n;
330 	int error;
331 
332 	l = curlwp; /* XXX */
333 
334 	if (device_class(root_device) != DV_IFNET)
335 		return (ENODEV);
336 
337 	/*
338 	 * XXX time must be non-zero when we init the interface or else
339 	 * the arp code will wedge.  [Fixed now in if_ether.c]
340 	 * However, the NFS attribute cache gives false "hits" when the
341 	 * current time < nfs_attrtimeo(nmp, np) so keep this in for now.
342 	 */
343 	if (time_second < NFS_MAXATTRTIMO) {
344 		ts.tv_sec = NFS_MAXATTRTIMO;
345 		ts.tv_nsec = 0;
346 		tc_setclock(&ts);
347 	}
348 
349 	/*
350 	 * Call nfs_boot_init() to fill in the nfs_diskless struct.
351 	 * Side effect:  Finds and configures a network interface.
352 	 */
353 	nd = kmem_zalloc(sizeof(*nd), KM_SLEEP);
354 	error = nfs_boot_init(nd, l);
355 	if (error) {
356 		kmem_free(nd, sizeof(*nd));
357 		return (error);
358 	}
359 
360 	/*
361 	 * Create the root mount point.
362 	 */
363 	error = nfs_mount_diskless(&nd->nd_root, "/", &mp, &vp, l);
364 	if (error)
365 		goto out;
366 	printf("root on %s\n", nd->nd_root.ndm_host);
367 
368 	/*
369 	 * Link it into the mount list.
370 	 */
371 	mountlist_append(mp);
372 	rootvp = vp;
373 	mp->mnt_vnodecovered = NULLVP;
374 	vfs_unbusy(mp);
375 
376 	/* Get root attributes (for the time). */
377 	vn_lock(vp, LK_SHARED | LK_RETRY);
378 	error = VOP_GETATTR(vp, &attr, l->l_cred);
379 	VOP_UNLOCK(vp);
380 	if (error)
381 		panic("nfs_mountroot: getattr for root");
382 	n = attr.va_atime.tv_sec;
383 #ifdef	DEBUG
384 	printf("root time: 0x%lx\n", n);
385 #endif
386 	setrootfstime(n);
387 
388 out:
389 	if (error)
390 		nfs_boot_cleanup(nd, l);
391 	kmem_free(nd, sizeof(*nd));
392 	return (error);
393 }
394 
395 /*
396  * Internal version of mount system call for diskless setup.
397  * Separate function because we used to call it twice.
398  * (once for root and once for swap)
399  */
400 static int
401 nfs_mount_diskless(struct nfs_dlmount *ndmntp, const char *mntname, struct mount **mpp, struct vnode **vpp, struct lwp *l)
402 	/* mntname:	 mount point name */
403 {
404 	struct mount *mp;
405 	struct mbuf *m;
406 	int error;
407 
408 	vfs_rootmountalloc(MOUNT_NFS, mntname, &mp);
409 
410 	mp->mnt_op = &nfs_vfsops;
411 
412 	/*
413 	 * Historical practice expects NFS root file systems to
414 	 * be initially mounted r/w.
415 	 */
416 	mp->mnt_flag &= ~MNT_RDONLY;
417 
418 	/* Get mbuf for server sockaddr. */
419 	m = m_get(M_WAIT, MT_SONAME);
420 	if (m == NULL)
421 		panic("nfs_mountroot: mget soname for %s", mntname);
422 	MCLAIM(m, &nfs_mowner);
423 	memcpy(mtod(m, void *), (void *)ndmntp->ndm_args.addr,
424 	      (m->m_len = ndmntp->ndm_args.addr->sa_len));
425 
426 	error = mountnfs(&ndmntp->ndm_args, mp, m, mntname,
427 			 ndmntp->ndm_args.hostname, vpp, l);
428 	if (error) {
429 		vfs_unbusy(mp);
430 		vfs_rele(mp);
431 		printf("nfs_mountroot: mount %s failed: %d\n",
432 		       mntname, error);
433 	} else
434 		*mpp = mp;
435 
436 	return (error);
437 }
438 
439 void
440 nfs_decode_args(struct nfsmount *nmp, struct nfs_args *argp, struct lwp *l)
441 {
442 	int s;
443 	int adjsock;
444 	int maxio;
445 
446 	s = splsoftnet();
447 
448 	/*
449 	 * Silently clear NFSMNT_NOCONN if it's a TCP mount, it makes
450 	 * no sense in that context.
451 	 */
452 	if (argp->sotype == SOCK_STREAM)
453 		argp->flags &= ~NFSMNT_NOCONN;
454 
455 	/*
456 	 * Cookie translation is not needed for v2, silently ignore it.
457 	 */
458 	if ((argp->flags & (NFSMNT_XLATECOOKIE|NFSMNT_NFSV3)) ==
459 	    NFSMNT_XLATECOOKIE)
460 		argp->flags &= ~NFSMNT_XLATECOOKIE;
461 
462 	/* Re-bind if rsrvd port requested and wasn't on one */
463 	adjsock = !(nmp->nm_flag & NFSMNT_RESVPORT)
464 		  && (argp->flags & NFSMNT_RESVPORT);
465 	/* Also re-bind if we're switching to/from a connected UDP socket */
466 	adjsock |= ((nmp->nm_flag & NFSMNT_NOCONN) !=
467 		    (argp->flags & NFSMNT_NOCONN));
468 
469 	/* Update flags. */
470 	nmp->nm_flag = argp->flags;
471 	splx(s);
472 
473 	if ((argp->flags & NFSMNT_TIMEO) && argp->timeo > 0) {
474 		nmp->nm_timeo = (argp->timeo * NFS_HZ + 5) / 10;
475 		if (nmp->nm_timeo < NFS_MINTIMEO)
476 			nmp->nm_timeo = NFS_MINTIMEO;
477 		else if (nmp->nm_timeo > NFS_MAXTIMEO)
478 			nmp->nm_timeo = NFS_MAXTIMEO;
479 	}
480 
481 	if ((argp->flags & NFSMNT_RETRANS) && argp->retrans > 1) {
482 		nmp->nm_retry = argp->retrans;
483 		if (nmp->nm_retry > NFS_MAXREXMIT)
484 			nmp->nm_retry = NFS_MAXREXMIT;
485 	}
486 
487 #ifndef NFS_V2_ONLY
488 	if (argp->flags & NFSMNT_NFSV3) {
489 		if (argp->sotype == SOCK_DGRAM)
490 			maxio = NFS_MAXDGRAMDATA;
491 		else
492 			maxio = NFS_MAXDATA;
493 	} else
494 #endif
495 		maxio = NFS_V2MAXDATA;
496 
497 	if ((argp->flags & NFSMNT_WSIZE) && argp->wsize > 0) {
498 		int osize = nmp->nm_wsize;
499 		nmp->nm_wsize = argp->wsize;
500 		/* Round down to multiple of blocksize */
501 		nmp->nm_wsize &= ~(NFS_FABLKSIZE - 1);
502 		if (nmp->nm_wsize <= 0)
503 			nmp->nm_wsize = NFS_FABLKSIZE;
504 		adjsock |= (nmp->nm_wsize != osize);
505 	}
506 	if (nmp->nm_wsize > maxio)
507 		nmp->nm_wsize = maxio;
508 	if (nmp->nm_wsize > MAXBSIZE)
509 		nmp->nm_wsize = MAXBSIZE;
510 
511 	if ((argp->flags & NFSMNT_RSIZE) && argp->rsize > 0) {
512 		int osize = nmp->nm_rsize;
513 		nmp->nm_rsize = argp->rsize;
514 		/* Round down to multiple of blocksize */
515 		nmp->nm_rsize &= ~(NFS_FABLKSIZE - 1);
516 		if (nmp->nm_rsize <= 0)
517 			nmp->nm_rsize = NFS_FABLKSIZE;
518 		adjsock |= (nmp->nm_rsize != osize);
519 	}
520 	if (nmp->nm_rsize > maxio)
521 		nmp->nm_rsize = maxio;
522 	if (nmp->nm_rsize > MAXBSIZE)
523 		nmp->nm_rsize = MAXBSIZE;
524 
525 	if ((argp->flags & NFSMNT_READDIRSIZE) && argp->readdirsize > 0) {
526 		nmp->nm_readdirsize = argp->readdirsize;
527 		/* Round down to multiple of minimum blocksize */
528 		nmp->nm_readdirsize &= ~(NFS_DIRFRAGSIZ - 1);
529 		if (nmp->nm_readdirsize < NFS_DIRFRAGSIZ)
530 			nmp->nm_readdirsize = NFS_DIRFRAGSIZ;
531 		/* Bigger than buffer size makes no sense */
532 		if (nmp->nm_readdirsize > NFS_DIRBLKSIZ)
533 			nmp->nm_readdirsize = NFS_DIRBLKSIZ;
534 	} else if (argp->flags & NFSMNT_RSIZE)
535 		nmp->nm_readdirsize = nmp->nm_rsize;
536 
537 	if (nmp->nm_readdirsize > maxio)
538 		nmp->nm_readdirsize = maxio;
539 
540 	if ((argp->flags & NFSMNT_MAXGRPS) && argp->maxgrouplist >= 0 &&
541 		argp->maxgrouplist <= NFS_MAXGRPS)
542 		nmp->nm_numgrps = argp->maxgrouplist;
543 	if ((argp->flags & NFSMNT_READAHEAD) && argp->readahead >= 0 &&
544 		argp->readahead <= NFS_MAXRAHEAD)
545 		nmp->nm_readahead = argp->readahead;
546 	if ((argp->flags & NFSMNT_DEADTHRESH) && argp->deadthresh >= 1 &&
547 		argp->deadthresh <= NFS_NEVERDEAD)
548 		nmp->nm_deadthresh = argp->deadthresh;
549 
550 	adjsock |= ((nmp->nm_sotype != argp->sotype) ||
551 		    (nmp->nm_soproto != argp->proto));
552 	nmp->nm_sotype = argp->sotype;
553 	nmp->nm_soproto = argp->proto;
554 
555 	if (nmp->nm_so && adjsock) {
556 		nfs_safedisconnect(nmp);
557 		if (nmp->nm_sotype == SOCK_DGRAM)
558 			while (nfs_connect(nmp, (struct nfsreq *)0, l)) {
559 				printf("nfs_args: retrying connect\n");
560 				kpause("nfscn3", false, hz, NULL);
561 			}
562 	}
563 }
564 
565 /*
566  * VFS Operations.
567  *
568  * mount system call
569  * It seems a bit dumb to copyinstr() the host and path here and then
570  * memcpy() them in mountnfs(), but I wanted to detect errors before
571  * doing the sockargs() call because sockargs() allocates an mbuf and
572  * an error after that means that I have to release the mbuf.
573  */
574 /* ARGSUSED */
575 int
576 nfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len)
577 {
578 	struct lwp *l = curlwp;
579 	int error;
580 	struct nfs_args *args = data;
581 	struct mbuf *nam;
582 	struct nfsmount *nmp = VFSTONFS(mp);
583 	struct sockaddr *sa;
584 	struct vnode *vp;
585 	char *pth, *hst;
586 	size_t len;
587 	u_char *nfh;
588 
589 	if (args == NULL)
590 		return EINVAL;
591 	if (*data_len < sizeof *args)
592 		return EINVAL;
593 
594 	if (mp->mnt_flag & MNT_GETARGS) {
595 
596 		if (nmp == NULL)
597 			return (EIO);
598 		if (args->addr != NULL) {
599 			sa = mtod(nmp->nm_nam, struct sockaddr *);
600 			error = copyout(sa, args->addr, sa->sa_len);
601 			if (error)
602 				return (error);
603 			args->addrlen = sa->sa_len;
604 		} else
605 			args->addrlen = 0;
606 
607 		args->version = NFS_ARGSVERSION;
608 		args->sotype = nmp->nm_sotype;
609 		args->proto = nmp->nm_soproto;
610 		args->fh = NULL;
611 		args->fhsize = 0;
612 		args->flags = nmp->nm_flag;
613 		args->wsize = nmp->nm_wsize;
614 		args->rsize = nmp->nm_rsize;
615 		args->readdirsize = nmp->nm_readdirsize;
616 		args->timeo = nmp->nm_timeo;
617 		args->retrans = nmp->nm_retry;
618 		args->maxgrouplist = nmp->nm_numgrps;
619 		args->readahead = nmp->nm_readahead;
620 		args->leaseterm = 0; /* dummy */
621 		args->deadthresh = nmp->nm_deadthresh;
622 		args->hostname = NULL;
623 		*data_len = sizeof *args;
624 		return 0;
625 	}
626 
627 	if (args->version != NFS_ARGSVERSION)
628 		return (EPROGMISMATCH);
629 	if (args->flags & (NFSMNT_NQNFS|NFSMNT_KERB))
630 		return (EPROGUNAVAIL);
631 #ifdef NFS_V2_ONLY
632 	if (args->flags & NFSMNT_NFSV3)
633 		return (EPROGMISMATCH);
634 #endif
635 	if (mp->mnt_flag & MNT_UPDATE) {
636 		if (nmp == NULL)
637 			return (EIO);
638 		/*
639 		 * When doing an update, we can't change from or to
640 		 * v3, or change cookie translation
641 		 */
642 		args->flags = (args->flags & ~(NFSMNT_NFSV3|NFSMNT_XLATECOOKIE)) |
643 		    (nmp->nm_flag & (NFSMNT_NFSV3|NFSMNT_XLATECOOKIE));
644 		nfs_decode_args(nmp, args, l);
645 		return (0);
646 	}
647 	if (args->fhsize < 0 || args->fhsize > NFSX_V3FHMAX)
648 		return (EINVAL);
649 	nfh = malloc(NFSX_V3FHMAX, M_TEMP, M_WAITOK);
650 	error = copyin(args->fh, nfh, args->fhsize);
651 	if (error)
652 		goto free_nfh;
653 	pth = malloc(MNAMELEN, M_TEMP, M_WAITOK);
654 	error = copyinstr(path, pth, MNAMELEN - 1, &len);
655 	if (error)
656 		goto free_pth;
657 	memset(&pth[len], 0, MNAMELEN - len);
658 	hst = malloc(MNAMELEN, M_TEMP, M_WAITOK);
659 	error = copyinstr(args->hostname, hst, MNAMELEN - 1, &len);
660 	if (error)
661 		goto free_hst;
662 	memset(&hst[len], 0, MNAMELEN - len);
663 	/* sockargs() call must be after above copyin() calls */
664 	error = sockargs(&nam, args->addr, args->addrlen, UIO_USERSPACE,
665 	    MT_SONAME);
666 	if (error)
667 		goto free_hst;
668 	MCLAIM(nam, &nfs_mowner);
669 	args->fh = nfh;
670 	error = mountnfs(args, mp, nam, pth, hst, &vp, l);
671 
672 free_hst:
673 	free(hst, M_TEMP);
674 free_pth:
675 	free(pth, M_TEMP);
676 free_nfh:
677 	free(nfh, M_TEMP);
678 
679 	return (error);
680 }
681 
682 /*
683  * Common code for mount and mountroot
684  */
685 int
686 mountnfs(struct nfs_args *argp, struct mount *mp, struct mbuf *nam, const char *pth, const char *hst, struct vnode **vpp, struct lwp *l)
687 {
688 	struct nfsmount *nmp;
689 	struct nfsnode *np;
690 	struct vnode *vp;
691 	int error;
692 	struct vattr *attrs;
693 	kauth_cred_t cr;
694 	char iosname[IOSTATNAMELEN];
695 
696 	/*
697 	 * If the number of nfs iothreads to use has never
698 	 * been set, create a reasonable number of them.
699 	 */
700 
701 	if (nfs_niothreads < 0) {
702 		nfs_set_niothreads(NFS_DEFAULT_NIOTHREADS);
703 	}
704 
705 	if (mp->mnt_flag & MNT_UPDATE) {
706 		nmp = VFSTONFS(mp);
707 		/* update paths, file handles, etc, here	XXX */
708 		m_freem(nam);
709 		return (0);
710 	} else {
711 		nmp = kmem_zalloc(sizeof(*nmp), KM_SLEEP);
712 		mp->mnt_data = nmp;
713 		TAILQ_INIT(&nmp->nm_uidlruhead);
714 		TAILQ_INIT(&nmp->nm_bufq);
715 		rw_init(&nmp->nm_writeverflock);
716 		mutex_init(&nmp->nm_lock, MUTEX_DEFAULT, IPL_NONE);
717 		cv_init(&nmp->nm_rcvcv, "nfsrcv");
718 		cv_init(&nmp->nm_sndcv, "nfssnd");
719 		cv_init(&nmp->nm_aiocv, "nfsaio");
720 		cv_init(&nmp->nm_disconcv, "nfsdis");
721 	}
722 	vfs_getnewfsid(mp);
723 	nmp->nm_mountp = mp;
724 
725 #ifndef NFS_V2_ONLY
726 	if ((argp->flags & NFSMNT_NFSV3) == 0)
727 #endif
728 	{
729 		if (argp->fhsize != NFSX_V2FH) {
730 			return EINVAL;
731 		}
732 	}
733 
734 	/*
735 	 * V2 can only handle 32 bit filesizes. For v3, nfs_fsinfo
736 	 * will overwrite this.
737 	 */
738 	nmp->nm_maxfilesize = 0xffffffffLL;
739 
740 	nmp->nm_timeo = NFS_TIMEO;
741 	nmp->nm_retry = NFS_RETRANS;
742 	nmp->nm_wsize = NFS_WSIZE;
743 	nmp->nm_rsize = NFS_RSIZE;
744 	nmp->nm_readdirsize = NFS_READDIRSIZE;
745 	nmp->nm_numgrps = NFS_MAXGRPS;
746 	nmp->nm_readahead = NFS_DEFRAHEAD;
747 	nmp->nm_deadthresh = NFS_DEFDEADTHRESH;
748 	error = set_statvfs_info(pth, UIO_SYSSPACE, hst, UIO_SYSSPACE,
749 	    mp->mnt_op->vfs_name, mp, l);
750 	if (error)
751 		goto bad;
752 	nmp->nm_nam = nam;
753 
754 	/* Set up the sockets and per-host congestion */
755 	nmp->nm_sotype = argp->sotype;
756 	nmp->nm_soproto = argp->proto;
757 
758 	nfs_decode_args(nmp, argp, l);
759 
760 	mp->mnt_fs_bshift = ffs(MIN(nmp->nm_rsize, nmp->nm_wsize)) - 1;
761 	mp->mnt_dev_bshift = DEV_BSHIFT;
762 
763 	/*
764 	 * For Connection based sockets (TCP,...) defer the connect until
765 	 * the first request, in case the server is not responding.
766 	 */
767 	if (nmp->nm_sotype == SOCK_DGRAM &&
768 		(error = nfs_connect(nmp, (struct nfsreq *)0, l)))
769 		goto bad;
770 
771 	/*
772 	 * This is silly, but it has to be set so that vinifod() works.
773 	 * We do not want to do an nfs_statvfs() here since we can get
774 	 * stuck on a dead server and we are holding a lock on the mount
775 	 * point.
776 	 */
777 	mp->mnt_stat.f_iosize = NFS_MAXDGRAMDATA;
778 	error = nfs_nget(mp, (nfsfh_t *)argp->fh, argp->fhsize, &np);
779 	if (error)
780 		goto bad;
781 	vp = NFSTOV(np);
782 	attrs = malloc(sizeof(struct vattr), M_TEMP, M_WAITOK);
783 	VOP_GETATTR(vp, attrs, l->l_cred);
784 	if ((nmp->nm_flag & NFSMNT_NFSV3) && (vp->v_type == VDIR)) {
785 		cr = kauth_cred_alloc();
786 		kauth_cred_setuid(cr, attrs->va_uid);
787 		kauth_cred_seteuid(cr, attrs->va_uid);
788 		kauth_cred_setsvuid(cr, attrs->va_uid);
789 		kauth_cred_setgid(cr, attrs->va_gid);
790 		kauth_cred_setegid(cr, attrs->va_gid);
791 		kauth_cred_setsvgid(cr, attrs->va_gid);
792 		nfs_cookieheuristic(vp, &nmp->nm_iflag, l, cr);
793 		kauth_cred_free(cr);
794 	}
795 	free(attrs, M_TEMP);
796 
797 	/*
798 	 * A reference count is needed on the nfsnode representing the
799 	 * remote root.  If this object is not persistent, then backward
800 	 * traversals of the mount point (i.e. "..") will not work if
801 	 * the nfsnode gets flushed out of the cache. Ufs does not have
802 	 * this problem, because one can identify root inodes by their
803 	 * number == UFS_ROOTINO (2). So, just unlock, but no rele.
804 	 */
805 
806 	nmp->nm_vnode = vp;
807 	if (vp->v_type == VNON)
808 		vp->v_type = VDIR;
809 	vp->v_vflag |= VV_ROOT;
810 	VOP_UNLOCK(vp);
811 	*vpp = vp;
812 
813 	snprintf(iosname, sizeof(iosname), "nfs%u", nfs_mount_count++);
814 	nmp->nm_stats = iostat_alloc(IOSTAT_NFS, nmp, iosname);
815 
816 	return (0);
817 bad:
818 	nfs_disconnect(nmp);
819 	rw_destroy(&nmp->nm_writeverflock);
820 	mutex_destroy(&nmp->nm_lock);
821 	cv_destroy(&nmp->nm_rcvcv);
822 	cv_destroy(&nmp->nm_sndcv);
823 	cv_destroy(&nmp->nm_aiocv);
824 	cv_destroy(&nmp->nm_disconcv);
825 	kmem_free(nmp, sizeof(*nmp));
826 	m_freem(nam);
827 	return (error);
828 }
829 
830 /*
831  * unmount system call
832  */
833 int
834 nfs_unmount(struct mount *mp, int mntflags)
835 {
836 	struct nfsmount *nmp = VFSTONFS(mp);
837 	struct vnode *vp;
838 	int error, flags = 0;
839 
840 	if (mntflags & MNT_FORCE) {
841 		mutex_enter(&nmp->nm_lock);
842 		flags |= FORCECLOSE;
843 		nmp->nm_iflag |= NFSMNT_DISMNTFORCE;
844 		mutex_exit(&nmp->nm_lock);
845 
846 	}
847 
848 	/*
849 	 * Goes something like this..
850 	 * - Check for activity on the root vnode (other than ourselves).
851 	 * - Call vflush() to clear out vnodes for this file system,
852 	 *   except for the root vnode.
853 	 * - Decrement reference on the vnode representing remote root.
854 	 * - Close the socket
855 	 * - Free up the data structures
856 	 */
857 	/*
858 	 * We need to decrement the ref. count on the nfsnode representing
859 	 * the remote root.  See comment in mountnfs().
860 	 */
861 	vp = nmp->nm_vnode;
862 	error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
863 	if (error != 0)
864 		goto err;
865 
866 	if ((mntflags & MNT_FORCE) == 0 && vrefcnt(vp) > 1) {
867 		VOP_UNLOCK(vp);
868 		error = EBUSY;
869 		goto err;
870 	}
871 
872 	error = vflush(mp, vp, flags);
873 	if (error) {
874 		VOP_UNLOCK(vp);
875 		goto err;
876 	}
877 
878 	/*
879 	 * We are now committed to the unmount; mark the mount structure
880 	 * as doomed so that any sleepers kicked awake by nfs_disconnect
881 	 * will go away cleanly.
882 	 */
883 	nmp->nm_iflag |= NFSMNT_DISMNT;
884 
885 	/*
886 	 * No new async I/O will be added, but await for pending
887 	 * ones to drain.
888 	 */
889 	while (nfs_iodbusy(nmp))
890 		kpause("nfsumnt", false, hz, NULL);
891 
892 	/*
893 	 * Clean up the stats... note that we carefully avoid decrementing
894 	 * nfs_mount_count here for good reason - we may not be unmounting
895 	 * the last thing mounted.
896 	 */
897 	iostat_free(nmp->nm_stats);
898 
899 	/*
900 	 * There is one reference count to get rid of here
901 	 * (see comment in mountnfs()).
902 	 */
903 	VOP_UNLOCK(vp);
904 	vgone(vp);
905 	nfs_disconnect(nmp);
906 	m_freem(nmp->nm_nam);
907 
908 	rw_destroy(&nmp->nm_writeverflock);
909 	mutex_destroy(&nmp->nm_lock);
910 	cv_destroy(&nmp->nm_rcvcv);
911 	cv_destroy(&nmp->nm_sndcv);
912 	cv_destroy(&nmp->nm_aiocv);
913 	cv_destroy(&nmp->nm_disconcv);
914 	kmem_free(nmp, sizeof(*nmp));
915 	return (0);
916 
917 err:
918 	if (mntflags & MNT_FORCE) {
919 		mutex_enter(&nmp->nm_lock);
920 		nmp->nm_iflag &= ~NFSMNT_DISMNTFORCE;
921 		mutex_exit(&nmp->nm_lock);
922 	}
923 
924 	return error;
925 }
926 
927 /*
928  * Return root of a filesystem
929  */
930 int
931 nfs_root(struct mount *mp, int lktype, struct vnode **vpp)
932 {
933 	struct vnode *vp;
934 	struct nfsmount *nmp;
935 	int error;
936 
937 	nmp = VFSTONFS(mp);
938 	vp = nmp->nm_vnode;
939 	vref(vp);
940 	error = vn_lock(vp, lktype | LK_RETRY);
941 	if (error != 0) {
942 		vrele(vp);
943 		return error;
944 	}
945 	*vpp = vp;
946 	return (0);
947 }
948 
949 extern int syncprt;
950 
951 static bool
952 nfs_sync_selector(void *cl, struct vnode *vp)
953 {
954 
955 	KASSERT(mutex_owned(vp->v_interlock));
956 
957 	return !LIST_EMPTY(&vp->v_dirtyblkhd) ||
958 	    (vp->v_iflag & VI_ONWORKLST) != 0;
959 }
960 
961 /*
962  * Flush out the buffer cache
963  */
964 /* ARGSUSED */
965 int
966 nfs_sync(struct mount *mp, int waitfor, kauth_cred_t cred)
967 {
968 	struct vnode *vp;
969 	struct vnode_iterator *marker;
970 	int error, allerror = 0;
971 
972 	/*
973 	 * Force stale buffer cache information to be flushed.
974 	 */
975 	vfs_vnode_iterator_init(mp, &marker);
976 	while ((vp = vfs_vnode_iterator_next(marker, nfs_sync_selector,
977 	    NULL)))
978 	{
979 		error = vn_lock(vp, LK_EXCLUSIVE);
980 		if (error) {
981 			vrele(vp);
982 			continue;
983 		}
984 		error = VOP_FSYNC(vp, cred,
985 		    waitfor == MNT_WAIT ? FSYNC_WAIT : 0, 0, 0);
986 		if (error)
987 			allerror = error;
988 		vput(vp);
989 	}
990 	vfs_vnode_iterator_destroy(marker);
991 	return allerror;
992 }
993 
994 /*
995  * NFS flat namespace lookup.
996  * Currently unsupported.
997  */
998 /* ARGSUSED */
999 int
1000 nfs_vget(struct mount *mp, ino_t ino, int lktype, struct vnode **vpp)
1001 {
1002 
1003 	return (EOPNOTSUPP);
1004 }
1005 
1006 /*
1007  * Do that sysctl thang...
1008  */
1009 static int
1010 sysctl_vfs_nfs_iothreads(SYSCTLFN_ARGS)
1011 {
1012 	struct sysctlnode node;
1013 	int val;
1014 	int error;
1015 
1016 	val = nfs_niothreads;
1017 	node = *rnode;
1018 	node.sysctl_data = &val;
1019         error = sysctl_lookup(SYSCTLFN_CALL(&node));
1020 	if (error || newp == NULL)
1021 		return error;
1022 
1023 	return nfs_set_niothreads(val);
1024 }
1025 
1026 SYSCTL_SETUP(nfs_sysctl_init, "nfs sysctl")
1027 {
1028 
1029 	sysctl_createv(clog, 0, NULL, NULL,
1030 		       CTLFLAG_PERMANENT,
1031 		       CTLTYPE_NODE, "nfs",
1032 		       SYSCTL_DESCR("NFS vfs options"),
1033 		       NULL, 0, NULL, 0,
1034 		       CTL_VFS, 2, CTL_EOL);
1035 	/*
1036 	 * XXX the "2" above could be dynamic, thereby eliminating one
1037 	 * more instance of the "number to vfs" mapping problem, but
1038 	 * "2" is the order as taken from sys/mount.h
1039 	 */
1040 
1041 	sysctl_createv(clog, 0, NULL, NULL,
1042 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1043 		       CTLTYPE_STRUCT, "nfsstats",
1044 		       SYSCTL_DESCR("NFS operation statistics"),
1045 		       NULL, 0, &nfsstats, sizeof(nfsstats),
1046 		       CTL_VFS, 2, NFS_NFSSTATS, CTL_EOL);
1047 	sysctl_createv(clog, 0, NULL, NULL,
1048 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1049 		       CTLTYPE_INT, "iothreads",
1050 		       SYSCTL_DESCR("Number of NFS client processes desired"),
1051 		       sysctl_vfs_nfs_iothreads, 0, NULL, 0,
1052 		       CTL_VFS, 2, NFS_IOTHREADS, CTL_EOL);
1053 }
1054 
1055 /* ARGSUSED */
1056 int
1057 nfs_fhtovp(struct mount *mp, struct fid *fid, int lktype, struct vnode **vpp)
1058 {
1059 	size_t fidsize;
1060 	size_t fhsize;
1061 	struct nfsnode *np;
1062 	int error;
1063 	struct vattr va;
1064 
1065 	fidsize = fid->fid_len;
1066 	if (fidsize < sizeof(*fid)) {
1067 		return EINVAL;
1068 	}
1069 	fhsize = fidsize - sizeof(*fid);
1070 	if ((fhsize % NFSX_UNSIGNED) != 0) {
1071 		return EINVAL;
1072 	}
1073 	if ((VFSTONFS(mp)->nm_flag & NFSMNT_NFSV3) != 0) {
1074 		if (fhsize > NFSX_V3FHMAX || fhsize == 0) {
1075 			return EINVAL;
1076 		}
1077 	} else {
1078 		if (fhsize != NFSX_V2FH) {
1079 			return EINVAL;
1080 		}
1081 	}
1082 	/* XXX lktype ignored */
1083 	error = nfs_nget(mp, (void *)fid->fid_data, fhsize, &np);
1084 	if (error) {
1085 		return error;
1086 	}
1087 	*vpp = NFSTOV(np);
1088 	error = VOP_GETATTR(*vpp, &va, kauth_cred_get());
1089 	if (error != 0) {
1090 		vput(*vpp);
1091 		*vpp = NULLVP;
1092 	}
1093 	return error;
1094 }
1095 
1096 /* ARGSUSED */
1097 int
1098 nfs_vptofh(struct vnode *vp, struct fid *buf, size_t *bufsize)
1099 {
1100 	struct nfsnode *np;
1101 	struct fid *fid;
1102 	size_t fidsize;
1103 	int error = 0;
1104 
1105 	np = VTONFS(vp);
1106 	fidsize = sizeof(*fid) + np->n_fhsize;
1107 	if (*bufsize < fidsize) {
1108 		error = E2BIG;
1109 	}
1110 	*bufsize = fidsize;
1111 	if (error == 0) {
1112 		struct fid fid_store;
1113 
1114 		fid = &fid_store;
1115 		memset(fid, 0, sizeof(*fid));
1116 		fid->fid_len = fidsize;
1117 		memcpy(buf, fid, sizeof(*fid));
1118 		memcpy(buf->fid_data, np->n_fhp, np->n_fhsize);
1119 	}
1120 	return error;
1121 }
1122 
1123 /*
1124  * Vfs start routine, a no-op.
1125  */
1126 /* ARGSUSED */
1127 int
1128 nfs_start(struct mount *mp, int flags)
1129 {
1130 
1131 	return (0);
1132 }
1133 
1134 /*
1135  * Called once at VFS init to initialize client-specific data structures.
1136  */
1137 void
1138 nfs_vfs_init(void)
1139 {
1140 
1141 	/* Initialize NFS server / client shared data. */
1142 	nfs_init();
1143 	nfs_node_init();
1144 
1145 	/* Initialize the kqueue structures */
1146 	nfs_kqinit();
1147 	/* Initialize the iod structures */
1148 	nfs_iodinit();
1149 
1150 	nfs_commitsize = uvmexp.npages << (PAGE_SHIFT - 4);
1151 }
1152 
1153 void
1154 nfs_vfs_done(void)
1155 {
1156 
1157 	nfs_node_done();
1158 	nfs_kqfini();
1159 	nfs_iodfini();
1160 	nfs_fini();
1161 }
1162