1 /*-
2  * Copyright (c) 1989, 1993
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  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	@(#)nfs_subs.c  8.8 (Berkeley) 5/22/95
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD: stable/10/sys/nfsclient/nfs_subs.c 252673 2013-07-04 00:54:23Z rmacklem $");
37 
38 /*
39  * These functions support the macros and help fiddle mbuf chains for
40  * the nfs op functions. They do things like create the rpc header and
41  * copy data between mbuf chains and uio lists.
42  */
43 
44 #include "opt_kdtrace.h"
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/bio.h>
50 #include <sys/buf.h>
51 #include <sys/proc.h>
52 #include <sys/mount.h>
53 #include <sys/vnode.h>
54 #include <sys/namei.h>
55 #include <sys/mbuf.h>
56 #include <sys/socket.h>
57 #include <sys/stat.h>
58 #include <sys/malloc.h>
59 #include <sys/rwlock.h>
60 #include <sys/sysent.h>
61 #include <sys/syscall.h>
62 #include <sys/sysproto.h>
63 #include <sys/taskqueue.h>
64 
65 #include <vm/vm.h>
66 #include <vm/vm_object.h>
67 #include <vm/vm_extern.h>
68 #include <vm/uma.h>
69 
70 #include <nfs/nfsproto.h>
71 #include <nfsclient/nfs.h>
72 #include <nfsclient/nfsnode.h>
73 #include <nfs/nfs_kdtrace.h>
74 #include <nfs/xdr_subs.h>
75 #include <nfsclient/nfsm_subs.h>
76 #include <nfsclient/nfsmount.h>
77 
78 #include <netinet/in.h>
79 
80 /*
81  * Note that stdarg.h and the ANSI style va_start macro is used for both
82  * ANSI and traditional C compilers.
83  */
84 #include <machine/stdarg.h>
85 
86 #ifdef KDTRACE_HOOKS
87 dtrace_nfsclient_attrcache_flush_probe_func_t
88     dtrace_nfsclient_attrcache_flush_done_probe;
89 uint32_t nfsclient_attrcache_flush_done_id;
90 
91 dtrace_nfsclient_attrcache_get_hit_probe_func_t
92     dtrace_nfsclient_attrcache_get_hit_probe;
93 uint32_t nfsclient_attrcache_get_hit_id;
94 
95 dtrace_nfsclient_attrcache_get_miss_probe_func_t
96     dtrace_nfsclient_attrcache_get_miss_probe;
97 uint32_t nfsclient_attrcache_get_miss_id;
98 
99 dtrace_nfsclient_attrcache_load_probe_func_t
100     dtrace_nfsclient_attrcache_load_done_probe;
101 uint32_t nfsclient_attrcache_load_done_id;
102 #endif /* !KDTRACE_HOOKS */
103 
104 /*
105  * Data items converted to xdr at startup, since they are constant
106  * This is kinda hokey, but may save a little time doing byte swaps
107  */
108 u_int32_t	nfs_xdrneg1;
109 u_int32_t	nfs_true, nfs_false;
110 
111 /* And other global data */
112 static u_int32_t nfs_xid = 0;
113 static enum vtype nv2tov_type[8]= {
114 	VNON, VREG, VDIR, VBLK, VCHR, VLNK, VNON,  VNON
115 };
116 
117 int		nfs_ticks;
118 int		nfs_pbuf_freecnt = -1;	/* start out unlimited */
119 
120 struct nfs_bufq	nfs_bufq;
121 static struct mtx nfs_xid_mtx;
122 struct task	nfs_nfsiodnew_task;
123 
124 /*
125  * and the reverse mapping from generic to Version 2 procedure numbers
126  */
127 int nfsv2_procid[NFS_NPROCS] = {
128 	NFSV2PROC_NULL,
129 	NFSV2PROC_GETATTR,
130 	NFSV2PROC_SETATTR,
131 	NFSV2PROC_LOOKUP,
132 	NFSV2PROC_NOOP,
133 	NFSV2PROC_READLINK,
134 	NFSV2PROC_READ,
135 	NFSV2PROC_WRITE,
136 	NFSV2PROC_CREATE,
137 	NFSV2PROC_MKDIR,
138 	NFSV2PROC_SYMLINK,
139 	NFSV2PROC_CREATE,
140 	NFSV2PROC_REMOVE,
141 	NFSV2PROC_RMDIR,
142 	NFSV2PROC_RENAME,
143 	NFSV2PROC_LINK,
144 	NFSV2PROC_READDIR,
145 	NFSV2PROC_NOOP,
146 	NFSV2PROC_STATFS,
147 	NFSV2PROC_NOOP,
148 	NFSV2PROC_NOOP,
149 	NFSV2PROC_NOOP,
150 	NFSV2PROC_NOOP,
151 };
152 
153 LIST_HEAD(nfsnodehashhead, nfsnode);
154 
155 u_int32_t
nfs_xid_gen(void)156 nfs_xid_gen(void)
157 {
158 	uint32_t xid;
159 
160 	mtx_lock(&nfs_xid_mtx);
161 
162 	/* Get a pretty random xid to start with */
163 	if (!nfs_xid)
164 		nfs_xid = random();
165 	/*
166 	 * Skip zero xid if it should ever happen.
167 	 */
168 	if (++nfs_xid == 0)
169 		nfs_xid++;
170 	xid = nfs_xid;
171 	mtx_unlock(&nfs_xid_mtx);
172 	return xid;
173 }
174 
175 /*
176  * copies a uio scatter/gather list to an mbuf chain.
177  * NOTE: can ony handle iovcnt == 1
178  */
179 int
nfsm_uiotombuf(struct uio * uiop,struct mbuf ** mq,int siz,caddr_t * bpos)180 nfsm_uiotombuf(struct uio *uiop, struct mbuf **mq, int siz, caddr_t *bpos)
181 {
182 	char *uiocp;
183 	struct mbuf *mp, *mp2;
184 	int xfer, left, mlen;
185 	int uiosiz, clflg, rem;
186 	char *cp;
187 
188 	KASSERT(uiop->uio_iovcnt == 1, ("nfsm_uiotombuf: iovcnt != 1"));
189 
190 	if (siz > MLEN)		/* or should it >= MCLBYTES ?? */
191 		clflg = 1;
192 	else
193 		clflg = 0;
194 	rem = nfsm_rndup(siz)-siz;
195 	mp = mp2 = *mq;
196 	while (siz > 0) {
197 		left = uiop->uio_iov->iov_len;
198 		uiocp = uiop->uio_iov->iov_base;
199 		if (left > siz)
200 			left = siz;
201 		uiosiz = left;
202 		while (left > 0) {
203 			mlen = M_TRAILINGSPACE(mp);
204 			if (mlen == 0) {
205 				if (clflg)
206 					mp = m_getcl(M_WAITOK, MT_DATA, 0);
207 				else
208 					mp = m_get(M_WAITOK, MT_DATA);
209 				mp2->m_next = mp;
210 				mp2 = mp;
211 				mlen = M_TRAILINGSPACE(mp);
212 			}
213 			xfer = (left > mlen) ? mlen : left;
214 #ifdef notdef
215 			/* Not Yet.. */
216 			if (uiop->uio_iov->iov_op != NULL)
217 				(*(uiop->uio_iov->iov_op))
218 				(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
219 			else
220 #endif
221 			if (uiop->uio_segflg == UIO_SYSSPACE)
222 				bcopy(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
223 			else
224 				copyin(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
225 			mp->m_len += xfer;
226 			left -= xfer;
227 			uiocp += xfer;
228 			uiop->uio_offset += xfer;
229 			uiop->uio_resid -= xfer;
230 		}
231 		uiop->uio_iov->iov_base =
232 		    (char *)uiop->uio_iov->iov_base + uiosiz;
233 		uiop->uio_iov->iov_len -= uiosiz;
234 		siz -= uiosiz;
235 	}
236 	if (rem > 0) {
237 		if (rem > M_TRAILINGSPACE(mp)) {
238 			mp = m_get(M_WAITOK, MT_DATA);
239 			mp2->m_next = mp;
240 		}
241 		cp = mtod(mp, caddr_t)+mp->m_len;
242 		for (left = 0; left < rem; left++)
243 			*cp++ = '\0';
244 		mp->m_len += rem;
245 		*bpos = cp;
246 	} else
247 		*bpos = mtod(mp, caddr_t)+mp->m_len;
248 	*mq = mp;
249 	return (0);
250 }
251 
252 /*
253  * Copy a string into mbufs for the hard cases...
254  */
255 int
nfsm_strtmbuf(struct mbuf ** mb,char ** bpos,const char * cp,long siz)256 nfsm_strtmbuf(struct mbuf **mb, char **bpos, const char *cp, long siz)
257 {
258 	struct mbuf *m1 = NULL, *m2;
259 	long left, xfer, len, tlen;
260 	u_int32_t *tl;
261 	int putsize;
262 
263 	putsize = 1;
264 	m2 = *mb;
265 	left = M_TRAILINGSPACE(m2);
266 	if (left > 0) {
267 		tl = ((u_int32_t *)(*bpos));
268 		*tl++ = txdr_unsigned(siz);
269 		putsize = 0;
270 		left -= NFSX_UNSIGNED;
271 		m2->m_len += NFSX_UNSIGNED;
272 		if (left > 0) {
273 			bcopy(cp, (caddr_t) tl, left);
274 			siz -= left;
275 			cp += left;
276 			m2->m_len += left;
277 			left = 0;
278 		}
279 	}
280 	/* Loop around adding mbufs */
281 	while (siz > 0) {
282 		if (siz > MLEN) {
283 			m1 = m_getcl(M_WAITOK, MT_DATA, 0);
284 			m1->m_len = MCLBYTES;
285 		} else {
286 			m1 = m_get(M_WAITOK, MT_DATA);
287 			m1->m_len = MLEN;
288 		}
289 		m2->m_next = m1;
290 		m2 = m1;
291 		tl = mtod(m1, u_int32_t *);
292 		tlen = 0;
293 		if (putsize) {
294 			*tl++ = txdr_unsigned(siz);
295 			m1->m_len -= NFSX_UNSIGNED;
296 			tlen = NFSX_UNSIGNED;
297 			putsize = 0;
298 		}
299 		if (siz < m1->m_len) {
300 			len = nfsm_rndup(siz);
301 			xfer = siz;
302 			if (xfer < len)
303 				*(tl+(xfer>>2)) = 0;
304 		} else {
305 			xfer = len = m1->m_len;
306 		}
307 		bcopy(cp, (caddr_t) tl, xfer);
308 		m1->m_len = len+tlen;
309 		siz -= xfer;
310 		cp += xfer;
311 	}
312 	*mb = m1;
313 	*bpos = mtod(m1, caddr_t)+m1->m_len;
314 	return (0);
315 }
316 
317 /*
318  * Called once to initialize data structures...
319  */
320 int
nfs_init(struct vfsconf * vfsp)321 nfs_init(struct vfsconf *vfsp)
322 {
323 	int i;
324 
325 	nfsmount_zone = uma_zcreate("NFSMOUNT", sizeof(struct nfsmount),
326 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
327 	nfs_true = txdr_unsigned(TRUE);
328 	nfs_false = txdr_unsigned(FALSE);
329 	nfs_xdrneg1 = txdr_unsigned(-1);
330 	nfs_ticks = (hz * NFS_TICKINTVL + 500) / 1000;
331 	if (nfs_ticks < 1)
332 		nfs_ticks = 1;
333 	/* Ensure async daemons disabled */
334 	for (i = 0; i < NFS_MAXASYNCDAEMON; i++) {
335 		nfs_iodwant[i] = NFSIOD_NOT_AVAILABLE;
336 		nfs_iodmount[i] = NULL;
337 	}
338 	nfs_nhinit();			/* Init the nfsnode table */
339 
340 	/*
341 	 * Initialize reply list and start timer
342 	 */
343 	mtx_init(&nfs_iod_mtx, "NFS iod lock", NULL, MTX_DEF);
344 	mtx_init(&nfs_xid_mtx, "NFS xid lock", NULL, MTX_DEF);
345 	TASK_INIT(&nfs_nfsiodnew_task, 0, nfs_nfsiodnew_tq, NULL);
346 
347 	nfs_pbuf_freecnt = nswbuf / 2 + 1;
348 
349 	return (0);
350 }
351 
352 int
nfs_uninit(struct vfsconf * vfsp)353 nfs_uninit(struct vfsconf *vfsp)
354 {
355 	int i;
356 
357 	/*
358 	 * Tell all nfsiod processes to exit. Clear nfs_iodmax, and wakeup
359 	 * any sleeping nfsiods so they check nfs_iodmax and exit.
360 	 * Drain nfsiodnew task before we wait for them to finish.
361 	 */
362 	mtx_lock(&nfs_iod_mtx);
363 	nfs_iodmax = 0;
364 	mtx_unlock(&nfs_iod_mtx);
365 	taskqueue_drain(taskqueue_thread, &nfs_nfsiodnew_task);
366 	mtx_lock(&nfs_iod_mtx);
367 	for (i = 0; i < nfs_numasync; i++)
368 		if (nfs_iodwant[i] == NFSIOD_AVAILABLE)
369 			wakeup(&nfs_iodwant[i]);
370 	/* The last nfsiod to exit will wake us up when nfs_numasync hits 0 */
371 	while (nfs_numasync)
372 		msleep(&nfs_numasync, &nfs_iod_mtx, PWAIT, "ioddie", 0);
373 	mtx_unlock(&nfs_iod_mtx);
374 	nfs_nhuninit();
375 	uma_zdestroy(nfsmount_zone);
376 	return (0);
377 }
378 
379 void
nfs_dircookie_lock(struct nfsnode * np)380 nfs_dircookie_lock(struct nfsnode *np)
381 {
382 	mtx_lock(&np->n_mtx);
383 	while (np->n_flag & NDIRCOOKIELK)
384 		(void) msleep(&np->n_flag, &np->n_mtx, PZERO, "nfsdirlk", 0);
385 	np->n_flag |= NDIRCOOKIELK;
386 	mtx_unlock(&np->n_mtx);
387 }
388 
389 void
nfs_dircookie_unlock(struct nfsnode * np)390 nfs_dircookie_unlock(struct nfsnode *np)
391 {
392 	mtx_lock(&np->n_mtx);
393 	np->n_flag &= ~NDIRCOOKIELK;
394 	wakeup(&np->n_flag);
395 	mtx_unlock(&np->n_mtx);
396 }
397 
398 int
nfs_upgrade_vnlock(struct vnode * vp)399 nfs_upgrade_vnlock(struct vnode *vp)
400 {
401 	int old_lock;
402 
403 	ASSERT_VOP_LOCKED(vp, "nfs_upgrade_vnlock");
404 	old_lock = VOP_ISLOCKED(vp);
405 	if (old_lock != LK_EXCLUSIVE) {
406 		KASSERT(old_lock == LK_SHARED,
407 		    ("nfs_upgrade_vnlock: wrong old_lock %d", old_lock));
408 		/* Upgrade to exclusive lock, this might block */
409 		vn_lock(vp, LK_UPGRADE | LK_RETRY);
410   	}
411 	return (old_lock);
412 }
413 
414 void
nfs_downgrade_vnlock(struct vnode * vp,int old_lock)415 nfs_downgrade_vnlock(struct vnode *vp, int old_lock)
416 {
417 	if (old_lock != LK_EXCLUSIVE) {
418 		KASSERT(old_lock == LK_SHARED, ("wrong old_lock %d", old_lock));
419 		/* Downgrade from exclusive lock. */
420 		vn_lock(vp, LK_DOWNGRADE | LK_RETRY);
421   	}
422 }
423 
424 void
nfs_printf(const char * fmt,...)425 nfs_printf(const char *fmt, ...)
426 {
427 	va_list ap;
428 
429 	mtx_lock(&Giant);
430 	va_start(ap, fmt);
431 	vprintf(fmt, ap);
432 	va_end(ap);
433 	mtx_unlock(&Giant);
434 }
435 
436 /*
437  * Attribute cache routines.
438  * nfs_loadattrcache() - loads or updates the cache contents from attributes
439  *	that are on the mbuf list
440  * nfs_getattrcache() - returns valid attributes if found in cache, returns
441  *	error otherwise
442  */
443 
444 /*
445  * Load the attribute cache (that lives in the nfsnode entry) with
446  * the values on the mbuf list and
447  * Iff vap not NULL
448  *    copy the attributes to *vaper
449  */
450 int
nfs_loadattrcache(struct vnode ** vpp,struct mbuf ** mdp,caddr_t * dposp,struct vattr * vaper,int dontshrink)451 nfs_loadattrcache(struct vnode **vpp, struct mbuf **mdp, caddr_t *dposp,
452 		  struct vattr *vaper, int dontshrink)
453 {
454 	struct vnode *vp = *vpp;
455 	struct vattr *vap;
456 	struct nfs_fattr *fp;
457 	struct nfsnode *np = NULL;
458 	int32_t t1;
459 	caddr_t cp2;
460 	int rdev;
461 	struct mbuf *md;
462 	enum vtype vtyp;
463 	u_short vmode;
464 	struct timespec mtime, mtime_save;
465 	int v3 = NFS_ISV3(vp);
466 	int error = 0;
467 	u_quad_t nsize;
468 	int setnsize;
469 
470 	md = *mdp;
471 	t1 = (mtod(md, caddr_t) + md->m_len) - *dposp;
472 	cp2 = nfsm_disct(mdp, dposp, NFSX_FATTR(v3), t1, M_WAITOK);
473 	if (cp2 == NULL) {
474 		error = EBADRPC;
475 		goto out;
476 	}
477 	fp = (struct nfs_fattr *)cp2;
478 	if (v3) {
479 		vtyp = nfsv3tov_type(fp->fa_type);
480 		vmode = fxdr_unsigned(u_short, fp->fa_mode);
481 		rdev = makedev(fxdr_unsigned(int, fp->fa3_rdev.specdata1),
482 			fxdr_unsigned(int, fp->fa3_rdev.specdata2));
483 		fxdr_nfsv3time(&fp->fa3_mtime, &mtime);
484 	} else {
485 		vtyp = nfsv2tov_type(fp->fa_type);
486 		vmode = fxdr_unsigned(u_short, fp->fa_mode);
487 		/*
488 		 * XXX
489 		 *
490 		 * The duplicate information returned in fa_type and fa_mode
491 		 * is an ambiguity in the NFS version 2 protocol.
492 		 *
493 		 * VREG should be taken literally as a regular file.  If a
494 		 * server intents to return some type information differently
495 		 * in the upper bits of the mode field (e.g. for sockets, or
496 		 * FIFOs), NFSv2 mandates fa_type to be VNON.  Anyway, we
497 		 * leave the examination of the mode bits even in the VREG
498 		 * case to avoid breakage for bogus servers, but we make sure
499 		 * that there are actually type bits set in the upper part of
500 		 * fa_mode (and failing that, trust the va_type field).
501 		 *
502 		 * NFSv3 cleared the issue, and requires fa_mode to not
503 		 * contain any type information (while also introduing sockets
504 		 * and FIFOs for fa_type).
505 		 */
506 		if (vtyp == VNON || (vtyp == VREG && (vmode & S_IFMT) != 0))
507 			vtyp = IFTOVT(vmode);
508 		rdev = fxdr_unsigned(int32_t, fp->fa2_rdev);
509 		fxdr_nfsv2time(&fp->fa2_mtime, &mtime);
510 
511 		/*
512 		 * Really ugly NFSv2 kludge.
513 		 */
514 		if (vtyp == VCHR && rdev == 0xffffffff)
515 			vtyp = VFIFO;
516 	}
517 
518 	/*
519 	 * If v_type == VNON it is a new node, so fill in the v_type,
520 	 * n_mtime fields. Check to see if it represents a special
521 	 * device, and if so, check for a possible alias. Once the
522 	 * correct vnode has been obtained, fill in the rest of the
523 	 * information.
524 	 */
525 	np = VTONFS(vp);
526 	mtx_lock(&np->n_mtx);
527 	if (vp->v_type != vtyp) {
528 		vp->v_type = vtyp;
529 		if (vp->v_type == VFIFO)
530 			vp->v_op = &nfs_fifoops;
531 		np->n_mtime = mtime;
532 	}
533 	vap = &np->n_vattr;
534 	vap->va_type = vtyp;
535 	vap->va_mode = (vmode & 07777);
536 	vap->va_rdev = rdev;
537 	mtime_save = vap->va_mtime;
538 	vap->va_mtime = mtime;
539 	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
540 	if (v3) {
541 		vap->va_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
542 		vap->va_uid = fxdr_unsigned(uid_t, fp->fa_uid);
543 		vap->va_gid = fxdr_unsigned(gid_t, fp->fa_gid);
544 		vap->va_size = fxdr_hyper(&fp->fa3_size);
545 		vap->va_blocksize = NFS_FABLKSIZE;
546 		vap->va_bytes = fxdr_hyper(&fp->fa3_used);
547 		vap->va_fileid = fxdr_unsigned(int32_t,
548 		    fp->fa3_fileid.nfsuquad[1]);
549 		fxdr_nfsv3time(&fp->fa3_atime, &vap->va_atime);
550 		fxdr_nfsv3time(&fp->fa3_ctime, &vap->va_ctime);
551 		vap->va_flags = 0;
552 		vap->va_filerev = 0;
553 	} else {
554 		vap->va_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
555 		vap->va_uid = fxdr_unsigned(uid_t, fp->fa_uid);
556 		vap->va_gid = fxdr_unsigned(gid_t, fp->fa_gid);
557 		vap->va_size = fxdr_unsigned(u_int32_t, fp->fa2_size);
558 		vap->va_blocksize = fxdr_unsigned(int32_t, fp->fa2_blocksize);
559 		vap->va_bytes = (u_quad_t)fxdr_unsigned(int32_t, fp->fa2_blocks)
560 		    * NFS_FABLKSIZE;
561 		vap->va_fileid = fxdr_unsigned(int32_t, fp->fa2_fileid);
562 		fxdr_nfsv2time(&fp->fa2_atime, &vap->va_atime);
563 		vap->va_flags = 0;
564 		vap->va_ctime.tv_sec = fxdr_unsigned(u_int32_t,
565 		    fp->fa2_ctime.nfsv2_sec);
566 		vap->va_ctime.tv_nsec = 0;
567 		vap->va_gen = fxdr_unsigned(u_int32_t, fp->fa2_ctime.nfsv2_usec);
568 		vap->va_filerev = 0;
569 	}
570 	np->n_attrstamp = time_second;
571 	setnsize = 0;
572 	nsize = 0;
573 	if (vap->va_size != np->n_size) {
574 		if (vap->va_type == VREG) {
575 			if (dontshrink && vap->va_size < np->n_size) {
576 				/*
577 				 * We've been told not to shrink the file;
578 				 * zero np->n_attrstamp to indicate that
579 				 * the attributes are stale.
580 				 */
581 				vap->va_size = np->n_size;
582 				np->n_attrstamp = 0;
583 				KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
584 				vnode_pager_setsize(vp, np->n_size);
585 			} else if (np->n_flag & NMODIFIED) {
586 				/*
587 				 * We've modified the file: Use the larger
588 				 * of our size, and the server's size.
589 				 */
590 				if (vap->va_size < np->n_size) {
591 					vap->va_size = np->n_size;
592 				} else {
593 					np->n_size = vap->va_size;
594 					np->n_flag |= NSIZECHANGED;
595 				}
596 				vnode_pager_setsize(vp, np->n_size);
597 			} else if (vap->va_size < np->n_size) {
598 				/*
599 				 * When shrinking the size, the call to
600 				 * vnode_pager_setsize() cannot be done
601 				 * with the mutex held, so delay it until
602 				 * after the mtx_unlock call.
603 				 */
604 				nsize = np->n_size = vap->va_size;
605 				np->n_flag |= NSIZECHANGED;
606 				setnsize = 1;
607 			} else {
608 				np->n_size = vap->va_size;
609 				np->n_flag |= NSIZECHANGED;
610 				vnode_pager_setsize(vp, np->n_size);
611 			}
612 		} else {
613 			np->n_size = vap->va_size;
614 		}
615 	}
616 	/*
617 	 * The following checks are added to prevent a race between (say)
618 	 * a READDIR+ and a WRITE.
619 	 * READDIR+, WRITE requests sent out.
620 	 * READDIR+ resp, WRITE resp received on client.
621 	 * However, the WRITE resp was handled before the READDIR+ resp
622 	 * causing the post op attrs from the write to be loaded first
623 	 * and the attrs from the READDIR+ to be loaded later. If this
624 	 * happens, we have stale attrs loaded into the attrcache.
625 	 * We detect this by for the mtime moving back. We invalidate the
626 	 * attrcache when this happens.
627 	 */
628 	if (timespeccmp(&mtime_save, &vap->va_mtime, >)) {
629 		/* Size changed or mtime went backwards */
630 		np->n_attrstamp = 0;
631 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
632 	}
633 	if (vaper != NULL) {
634 		bcopy((caddr_t)vap, (caddr_t)vaper, sizeof(*vap));
635 		if (np->n_flag & NCHG) {
636 			if (np->n_flag & NACC)
637 				vaper->va_atime = np->n_atim;
638 			if (np->n_flag & NUPD)
639 				vaper->va_mtime = np->n_mtim;
640 		}
641 	}
642 
643 #ifdef KDTRACE_HOOKS
644 	if (np->n_attrstamp != 0)
645 		KDTRACE_NFS_ATTRCACHE_LOAD_DONE(vp, &np->n_vattr, 0);
646 #endif
647 	mtx_unlock(&np->n_mtx);
648 	if (setnsize)
649 		vnode_pager_setsize(vp, nsize);
650 out:
651 #ifdef KDTRACE_HOOKS
652 	if (error)
653 		KDTRACE_NFS_ATTRCACHE_LOAD_DONE(vp, NULL, error);
654 #endif
655 	return (error);
656 }
657 
658 #ifdef NFS_ACDEBUG
659 #include <sys/sysctl.h>
660 SYSCTL_DECL(_vfs_oldnfs);
661 static int nfs_acdebug;
662 SYSCTL_INT(_vfs_oldnfs, OID_AUTO, acdebug, CTLFLAG_RW, &nfs_acdebug, 0,
663     "Toggle acdebug (attribute cache debug) flag");
664 #endif
665 
666 /*
667  * Check the time stamp
668  * If the cache is valid, copy contents to *vap and return 0
669  * otherwise return an error
670  */
671 int
nfs_getattrcache(struct vnode * vp,struct vattr * vaper)672 nfs_getattrcache(struct vnode *vp, struct vattr *vaper)
673 {
674 	struct nfsnode *np;
675 	struct vattr *vap;
676 	struct nfsmount *nmp;
677 	int timeo;
678 
679 	np = VTONFS(vp);
680 	vap = &np->n_vattr;
681 	nmp = VFSTONFS(vp->v_mount);
682 #ifdef NFS_ACDEBUG
683 	mtx_lock(&Giant);	/* nfs_printf() */
684 #endif
685 	mtx_lock(&np->n_mtx);
686 	/* XXX n_mtime doesn't seem to be updated on a miss-and-reload */
687 	timeo = (time_second - np->n_mtime.tv_sec) / 10;
688 
689 #ifdef NFS_ACDEBUG
690 	if (nfs_acdebug>1)
691 		nfs_printf("nfs_getattrcache: initial timeo = %d\n", timeo);
692 #endif
693 
694 	if (vap->va_type == VDIR) {
695 		if ((np->n_flag & NMODIFIED) || timeo < nmp->nm_acdirmin)
696 			timeo = nmp->nm_acdirmin;
697 		else if (timeo > nmp->nm_acdirmax)
698 			timeo = nmp->nm_acdirmax;
699 	} else {
700 		if ((np->n_flag & NMODIFIED) || timeo < nmp->nm_acregmin)
701 			timeo = nmp->nm_acregmin;
702 		else if (timeo > nmp->nm_acregmax)
703 			timeo = nmp->nm_acregmax;
704 	}
705 
706 #ifdef NFS_ACDEBUG
707 	if (nfs_acdebug > 2)
708 		nfs_printf("acregmin %d; acregmax %d; acdirmin %d; acdirmax %d\n",
709 			   nmp->nm_acregmin, nmp->nm_acregmax,
710 			   nmp->nm_acdirmin, nmp->nm_acdirmax);
711 
712 	if (nfs_acdebug)
713 		nfs_printf("nfs_getattrcache: age = %d; final timeo = %d\n",
714 			   (time_second - np->n_attrstamp), timeo);
715 #endif
716 
717 	if ((time_second - np->n_attrstamp) >= timeo) {
718 		nfsstats.attrcache_misses++;
719 		mtx_unlock(&np->n_mtx);
720 #ifdef NFS_ACDEBUG
721 		mtx_unlock(&Giant);	/* nfs_printf() */
722 #endif
723 		KDTRACE_NFS_ATTRCACHE_GET_MISS(vp);
724 		return (ENOENT);
725 	}
726 	nfsstats.attrcache_hits++;
727 	if (vap->va_size != np->n_size) {
728 		if (vap->va_type == VREG) {
729 			if (np->n_flag & NMODIFIED) {
730 				if (vap->va_size < np->n_size)
731 					vap->va_size = np->n_size;
732 				else
733 					np->n_size = vap->va_size;
734 			} else {
735 				np->n_size = vap->va_size;
736 			}
737 			vnode_pager_setsize(vp, np->n_size);
738 		} else {
739 			np->n_size = vap->va_size;
740 		}
741 	}
742 	bcopy((caddr_t)vap, (caddr_t)vaper, sizeof(struct vattr));
743 	if (np->n_flag & NCHG) {
744 		if (np->n_flag & NACC)
745 			vaper->va_atime = np->n_atim;
746 		if (np->n_flag & NUPD)
747 			vaper->va_mtime = np->n_mtim;
748 	}
749 	mtx_unlock(&np->n_mtx);
750 #ifdef NFS_ACDEBUG
751 	mtx_unlock(&Giant);	/* nfs_printf() */
752 #endif
753 	KDTRACE_NFS_ATTRCACHE_GET_HIT(vp, vap);
754 	return (0);
755 }
756 
757 /*
758  * Purge all cached information about an NFS vnode including name
759  * cache entries, the attribute cache, and the access cache.  This is
760  * called when an NFS request for a node fails with a stale
761  * filehandle.
762  */
763 void
nfs_purgecache(struct vnode * vp)764 nfs_purgecache(struct vnode *vp)
765 {
766 	struct nfsnode *np;
767 	int i;
768 
769 	np = VTONFS(vp);
770 	cache_purge(vp);
771 	mtx_lock(&np->n_mtx);
772 	np->n_attrstamp = 0;
773 	KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
774 	for (i = 0; i < NFS_ACCESSCACHESIZE; i++)
775 		np->n_accesscache[i].stamp = 0;
776 	KDTRACE_NFS_ACCESSCACHE_FLUSH_DONE(vp);
777 	mtx_unlock(&np->n_mtx);
778 }
779 
780 static nfsuint64 nfs_nullcookie = { { 0, 0 } };
781 /*
782  * This function finds the directory cookie that corresponds to the
783  * logical byte offset given.
784  */
785 nfsuint64 *
nfs_getcookie(struct nfsnode * np,off_t off,int add)786 nfs_getcookie(struct nfsnode *np, off_t off, int add)
787 {
788 	struct nfsdmap *dp, *dp2;
789 	int pos;
790 	nfsuint64 *retval = NULL;
791 
792 	pos = (uoff_t)off / NFS_DIRBLKSIZ;
793 	if (pos == 0 || off < 0) {
794 		KASSERT(!add, ("nfs getcookie add at <= 0"));
795 		return (&nfs_nullcookie);
796 	}
797 	pos--;
798 	dp = LIST_FIRST(&np->n_cookies);
799 	if (!dp) {
800 		if (add) {
801 			dp = malloc(sizeof (struct nfsdmap),
802 				M_NFSDIROFF, M_WAITOK);
803 			dp->ndm_eocookie = 0;
804 			LIST_INSERT_HEAD(&np->n_cookies, dp, ndm_list);
805 		} else
806 			goto out;
807 	}
808 	while (pos >= NFSNUMCOOKIES) {
809 		pos -= NFSNUMCOOKIES;
810 		if (LIST_NEXT(dp, ndm_list)) {
811 			if (!add && dp->ndm_eocookie < NFSNUMCOOKIES &&
812 			    pos >= dp->ndm_eocookie)
813 				goto out;
814 			dp = LIST_NEXT(dp, ndm_list);
815 		} else if (add) {
816 			dp2 = malloc(sizeof (struct nfsdmap),
817 				M_NFSDIROFF, M_WAITOK);
818 			dp2->ndm_eocookie = 0;
819 			LIST_INSERT_AFTER(dp, dp2, ndm_list);
820 			dp = dp2;
821 		} else
822 			goto out;
823 	}
824 	if (pos >= dp->ndm_eocookie) {
825 		if (add)
826 			dp->ndm_eocookie = pos + 1;
827 		else
828 			goto out;
829 	}
830 	retval = &dp->ndm_cookies[pos];
831 out:
832 	return (retval);
833 }
834 
835 /*
836  * Invalidate cached directory information, except for the actual directory
837  * blocks (which are invalidated separately).
838  * Done mainly to avoid the use of stale offset cookies.
839  */
840 void
nfs_invaldir(struct vnode * vp)841 nfs_invaldir(struct vnode *vp)
842 {
843 	struct nfsnode *np = VTONFS(vp);
844 
845 	KASSERT(vp->v_type == VDIR, ("nfs: invaldir not dir"));
846 	nfs_dircookie_lock(np);
847 	np->n_direofoffset = 0;
848 	np->n_cookieverf.nfsuquad[0] = 0;
849 	np->n_cookieverf.nfsuquad[1] = 0;
850 	if (LIST_FIRST(&np->n_cookies))
851 		LIST_FIRST(&np->n_cookies)->ndm_eocookie = 0;
852 	nfs_dircookie_unlock(np);
853 }
854 
855 /*
856  * The write verifier has changed (probably due to a server reboot), so all
857  * B_NEEDCOMMIT blocks will have to be written again. Since they are on the
858  * dirty block list as B_DELWRI, all this takes is clearing the B_NEEDCOMMIT
859  * and B_CLUSTEROK flags.  Once done the new write verifier can be set for the
860  * mount point.
861  *
862  * B_CLUSTEROK must be cleared along with B_NEEDCOMMIT because stage 1 data
863  * writes are not clusterable.
864  */
865 void
nfs_clearcommit(struct mount * mp)866 nfs_clearcommit(struct mount *mp)
867 {
868 	struct vnode *vp, *nvp;
869 	struct buf *bp, *nbp;
870 	struct bufobj *bo;
871 
872 	MNT_VNODE_FOREACH_ALL(vp, mp, nvp) {
873 		bo = &vp->v_bufobj;
874 		vholdl(vp);
875 		VI_UNLOCK(vp);
876 		BO_LOCK(bo);
877 		TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
878 			if (!BUF_ISLOCKED(bp) &&
879 			    (bp->b_flags & (B_DELWRI | B_NEEDCOMMIT))
880 				== (B_DELWRI | B_NEEDCOMMIT))
881 				bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
882 		}
883 		BO_UNLOCK(bo);
884 		vdrop(vp);
885 	}
886 }
887 
888 /*
889  * Helper functions for former macros.  Some of these should be
890  * moved to their callers.
891  */
892 
893 int
nfsm_mtofh_xx(struct vnode * d,struct vnode ** v,int v3,int * f,struct mbuf ** md,caddr_t * dpos)894 nfsm_mtofh_xx(struct vnode *d, struct vnode **v, int v3, int *f,
895     struct mbuf **md, caddr_t *dpos)
896 {
897 	struct nfsnode *ttnp;
898 	struct vnode *ttvp;
899 	nfsfh_t *ttfhp;
900 	u_int32_t *tl;
901 	int ttfhsize;
902 	int t1;
903 
904 	if (v3) {
905 		tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
906 		if (tl == NULL)
907 			return EBADRPC;
908 		*f = fxdr_unsigned(int, *tl);
909 	} else
910 		*f = 1;
911 	if (*f) {
912 		t1 = nfsm_getfh_xx(&ttfhp, &ttfhsize, (v3), md, dpos);
913 		if (t1 != 0)
914 			return t1;
915 		t1 = nfs_nget(d->v_mount, ttfhp, ttfhsize, &ttnp, LK_EXCLUSIVE);
916 		if (t1 != 0)
917 			return t1;
918 		*v = NFSTOV(ttnp);
919 	}
920 	if (v3) {
921 		tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
922 		if (tl == NULL)
923 			return EBADRPC;
924 		if (*f)
925 			*f = fxdr_unsigned(int, *tl);
926 		else if (fxdr_unsigned(int, *tl))
927 			nfsm_adv_xx(NFSX_V3FATTR, md, dpos);
928 	}
929 	if (*f) {
930 		ttvp = *v;
931 		t1 = nfs_loadattrcache(&ttvp, md, dpos, NULL, 0);
932 		if (t1)
933 			return t1;
934 		*v = ttvp;
935 	}
936 	return 0;
937 }
938 
939 int
nfsm_getfh_xx(nfsfh_t ** f,int * s,int v3,struct mbuf ** md,caddr_t * dpos)940 nfsm_getfh_xx(nfsfh_t **f, int *s, int v3, struct mbuf **md, caddr_t *dpos)
941 {
942 	u_int32_t *tl;
943 
944 	if (v3) {
945 		tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
946 		if (tl == NULL)
947 			return EBADRPC;
948 		*s = fxdr_unsigned(int, *tl);
949 		if (*s <= 0 || *s > NFSX_V3FHMAX)
950 			return EBADRPC;
951 	} else
952 		*s = NFSX_V2FH;
953 	*f = nfsm_dissect_xx(nfsm_rndup(*s), md, dpos);
954 	if (*f == NULL)
955 		return EBADRPC;
956 	else
957 		return 0;
958 }
959 
960 
961 int
nfsm_loadattr_xx(struct vnode ** v,struct vattr * va,struct mbuf ** md,caddr_t * dpos)962 nfsm_loadattr_xx(struct vnode **v, struct vattr *va, struct mbuf **md,
963 		 caddr_t *dpos)
964 {
965 	int t1;
966 
967 	struct vnode *ttvp = *v;
968 	t1 = nfs_loadattrcache(&ttvp, md, dpos, va, 0);
969 	if (t1 != 0)
970 		return t1;
971 	*v = ttvp;
972 	return 0;
973 }
974 
975 int
nfsm_postop_attr_xx(struct vnode ** v,int * f,struct vattr * va,struct mbuf ** md,caddr_t * dpos)976 nfsm_postop_attr_xx(struct vnode **v, int *f, struct vattr *va,
977 		    struct mbuf **md, caddr_t *dpos)
978 {
979 	u_int32_t *tl;
980 	int t1;
981 
982 	struct vnode *ttvp = *v;
983 	tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
984 	if (tl == NULL)
985 		return EBADRPC;
986 	*f = fxdr_unsigned(int, *tl);
987 	if (*f != 0) {
988 		t1 = nfs_loadattrcache(&ttvp, md, dpos, va, 1);
989 		if (t1 != 0) {
990 			*f = 0;
991 			return t1;
992 		}
993 		*v = ttvp;
994 	}
995 	return 0;
996 }
997 
998 int
nfsm_wcc_data_xx(struct vnode ** v,int * f,struct mbuf ** md,caddr_t * dpos)999 nfsm_wcc_data_xx(struct vnode **v, int *f, struct mbuf **md, caddr_t *dpos)
1000 {
1001 	u_int32_t *tl;
1002 	int ttattrf, ttretf = 0;
1003 	int t1;
1004 
1005 	tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
1006 	if (tl == NULL)
1007 		return EBADRPC;
1008 	if (*tl == nfs_true) {
1009 		tl = nfsm_dissect_xx(6 * NFSX_UNSIGNED, md, dpos);
1010 		if (tl == NULL)
1011 			return EBADRPC;
1012 		mtx_lock(&(VTONFS(*v))->n_mtx);
1013 		if (*f)
1014  			ttretf = (VTONFS(*v)->n_mtime.tv_sec == fxdr_unsigned(u_int32_t, *(tl + 2)) &&
1015 				  VTONFS(*v)->n_mtime.tv_nsec == fxdr_unsigned(u_int32_t, *(tl + 3)));
1016 		mtx_unlock(&(VTONFS(*v))->n_mtx);
1017 	}
1018 	t1 = nfsm_postop_attr_xx(v, &ttattrf, NULL, md, dpos);
1019 	if (t1)
1020 		return t1;
1021 	if (*f)
1022 		*f = ttretf;
1023 	else
1024 		*f = ttattrf;
1025 	return 0;
1026 }
1027 
1028 int
nfsm_strtom_xx(const char * a,int s,int m,struct mbuf ** mb,caddr_t * bpos)1029 nfsm_strtom_xx(const char *a, int s, int m, struct mbuf **mb, caddr_t *bpos)
1030 {
1031 	u_int32_t *tl;
1032 	int t1;
1033 
1034 	if (s > m)
1035 		return ENAMETOOLONG;
1036 	t1 = nfsm_rndup(s) + NFSX_UNSIGNED;
1037 	if (t1 <= M_TRAILINGSPACE(*mb)) {
1038 		tl = nfsm_build_xx(t1, mb, bpos);
1039 		*tl++ = txdr_unsigned(s);
1040 		*(tl + ((t1 >> 2) - 2)) = 0;
1041 		bcopy(a, tl, s);
1042 	} else {
1043 		t1 = nfsm_strtmbuf(mb, bpos, a, s);
1044 		if (t1 != 0)
1045 			return t1;
1046 	}
1047 	return 0;
1048 }
1049 
1050 int
nfsm_fhtom_xx(struct vnode * v,int v3,struct mbuf ** mb,caddr_t * bpos)1051 nfsm_fhtom_xx(struct vnode *v, int v3, struct mbuf **mb, caddr_t *bpos)
1052 {
1053 	u_int32_t *tl;
1054 	int t1;
1055 	caddr_t cp;
1056 
1057 	if (v3) {
1058 		t1 = nfsm_rndup(VTONFS(v)->n_fhsize) + NFSX_UNSIGNED;
1059 		if (t1 < M_TRAILINGSPACE(*mb)) {
1060 			tl = nfsm_build_xx(t1, mb, bpos);
1061 			*tl++ = txdr_unsigned(VTONFS(v)->n_fhsize);
1062 			*(tl + ((t1 >> 2) - 2)) = 0;
1063 			bcopy(VTONFS(v)->n_fhp, tl, VTONFS(v)->n_fhsize);
1064 		} else {
1065 			t1 = nfsm_strtmbuf(mb, bpos,
1066 			    (const char *)VTONFS(v)->n_fhp,
1067 			    VTONFS(v)->n_fhsize);
1068 			if (t1 != 0)
1069 				return t1;
1070 		}
1071 	} else {
1072 		cp = nfsm_build_xx(NFSX_V2FH, mb, bpos);
1073 		bcopy(VTONFS(v)->n_fhp, cp, NFSX_V2FH);
1074 	}
1075 	return 0;
1076 }
1077 
1078 void
nfsm_v3attrbuild_xx(struct vattr * va,int full,struct mbuf ** mb,caddr_t * bpos)1079 nfsm_v3attrbuild_xx(struct vattr *va, int full, struct mbuf **mb,
1080     caddr_t *bpos)
1081 {
1082 	u_int32_t *tl;
1083 
1084 	if (va->va_mode != (mode_t)VNOVAL) {
1085 		tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
1086 		*tl++ = nfs_true;
1087 		*tl = txdr_unsigned(va->va_mode);
1088 	} else {
1089 		tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
1090 		*tl = nfs_false;
1091 	}
1092 	if (full && va->va_uid != (uid_t)VNOVAL) {
1093 		tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
1094 		*tl++ = nfs_true;
1095 		*tl = txdr_unsigned(va->va_uid);
1096 	} else {
1097 		tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
1098 		*tl = nfs_false;
1099 	}
1100 	if (full && va->va_gid != (gid_t)VNOVAL) {
1101 		tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
1102 		*tl++ = nfs_true;
1103 		*tl = txdr_unsigned(va->va_gid);
1104 	} else {
1105 		tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
1106 		*tl = nfs_false;
1107 	}
1108 	if (full && va->va_size != VNOVAL) {
1109 		tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
1110 		*tl++ = nfs_true;
1111 		txdr_hyper(va->va_size, tl);
1112 	} else {
1113 		tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
1114 		*tl = nfs_false;
1115 	}
1116 	if (va->va_atime.tv_sec != VNOVAL) {
1117 		if ((va->va_vaflags & VA_UTIMES_NULL) == 0) {
1118 			tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
1119 			*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
1120 			txdr_nfsv3time(&va->va_atime, tl);
1121 		} else {
1122 			tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
1123 			*tl = txdr_unsigned(NFSV3SATTRTIME_TOSERVER);
1124 		}
1125 	} else {
1126 		tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
1127 		*tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
1128 	}
1129 	if (va->va_mtime.tv_sec != VNOVAL) {
1130 		if ((va->va_vaflags & VA_UTIMES_NULL) == 0) {
1131 			tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
1132 			*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
1133 			txdr_nfsv3time(&va->va_mtime, tl);
1134 		} else {
1135 			tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
1136 			*tl = txdr_unsigned(NFSV3SATTRTIME_TOSERVER);
1137 		}
1138 	} else {
1139 		tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
1140 		*tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
1141 	}
1142 }
1143