xref: /freebsd/sys/fs/nfsclient/nfs_clvnops.c (revision a10cee30c94cf5944826d2a495e9cdf339dfbcc8)
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  *	from nfs_vnops.c	8.16 (Berkeley) 5/27/95
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 /*
39  * vnode op calls for Sun NFS version 2, 3 and 4
40  */
41 
42 #include "opt_kdtrace.h"
43 #include "opt_inet.h"
44 
45 #include <sys/param.h>
46 #include <sys/kernel.h>
47 #include <sys/systm.h>
48 #include <sys/resourcevar.h>
49 #include <sys/proc.h>
50 #include <sys/mount.h>
51 #include <sys/bio.h>
52 #include <sys/buf.h>
53 #include <sys/jail.h>
54 #include <sys/malloc.h>
55 #include <sys/mbuf.h>
56 #include <sys/namei.h>
57 #include <sys/socket.h>
58 #include <sys/vnode.h>
59 #include <sys/dirent.h>
60 #include <sys/fcntl.h>
61 #include <sys/lockf.h>
62 #include <sys/stat.h>
63 #include <sys/sysctl.h>
64 #include <sys/signalvar.h>
65 
66 #include <vm/vm.h>
67 #include <vm/vm_extern.h>
68 #include <vm/vm_object.h>
69 
70 #include <fs/nfs/nfsport.h>
71 #include <fs/nfsclient/nfsnode.h>
72 #include <fs/nfsclient/nfsmount.h>
73 #include <fs/nfsclient/nfs.h>
74 #include <fs/nfsclient/nfs_kdtrace.h>
75 
76 #include <net/if.h>
77 #include <netinet/in.h>
78 #include <netinet/in_var.h>
79 
80 #include <nfs/nfs_lock.h>
81 
82 #ifdef KDTRACE_HOOKS
83 #include <sys/dtrace_bsd.h>
84 
85 dtrace_nfsclient_accesscache_flush_probe_func_t
86 		dtrace_nfscl_accesscache_flush_done_probe;
87 uint32_t	nfscl_accesscache_flush_done_id;
88 
89 dtrace_nfsclient_accesscache_get_probe_func_t
90 		dtrace_nfscl_accesscache_get_hit_probe,
91 		dtrace_nfscl_accesscache_get_miss_probe;
92 uint32_t	nfscl_accesscache_get_hit_id;
93 uint32_t	nfscl_accesscache_get_miss_id;
94 
95 dtrace_nfsclient_accesscache_load_probe_func_t
96 		dtrace_nfscl_accesscache_load_done_probe;
97 uint32_t	nfscl_accesscache_load_done_id;
98 #endif /* !KDTRACE_HOOKS */
99 
100 /* Defs */
101 #define	TRUE	1
102 #define	FALSE	0
103 
104 extern struct nfsstats newnfsstats;
105 extern int nfsrv_useacl;
106 MALLOC_DECLARE(M_NEWNFSREQ);
107 
108 /*
109  * Ifdef for FreeBSD-current merged buffer cache. It is unfortunate that these
110  * calls are not in getblk() and brelse() so that they would not be necessary
111  * here.
112  */
113 #ifndef B_VMIO
114 #define	vfs_busy_pages(bp, f)
115 #endif
116 
117 static vop_read_t	nfsfifo_read;
118 static vop_write_t	nfsfifo_write;
119 static vop_close_t	nfsfifo_close;
120 static int	nfs_setattrrpc(struct vnode *, struct vattr *, struct ucred *,
121 		    struct thread *);
122 static vop_lookup_t	nfs_lookup;
123 static vop_create_t	nfs_create;
124 static vop_mknod_t	nfs_mknod;
125 static vop_open_t	nfs_open;
126 static vop_pathconf_t	nfs_pathconf;
127 static vop_close_t	nfs_close;
128 static vop_access_t	nfs_access;
129 static vop_getattr_t	nfs_getattr;
130 static vop_setattr_t	nfs_setattr;
131 static vop_read_t	nfs_read;
132 static vop_fsync_t	nfs_fsync;
133 static vop_remove_t	nfs_remove;
134 static vop_link_t	nfs_link;
135 static vop_rename_t	nfs_rename;
136 static vop_mkdir_t	nfs_mkdir;
137 static vop_rmdir_t	nfs_rmdir;
138 static vop_symlink_t	nfs_symlink;
139 static vop_readdir_t	nfs_readdir;
140 static vop_strategy_t	nfs_strategy;
141 static vop_lock1_t	nfs_lock1;
142 static	int	nfs_lookitup(struct vnode *, char *, int,
143 		    struct ucred *, struct thread *, struct nfsnode **);
144 static	int	nfs_sillyrename(struct vnode *, struct vnode *,
145 		    struct componentname *);
146 static vop_access_t	nfsspec_access;
147 static vop_readlink_t	nfs_readlink;
148 static vop_print_t	nfs_print;
149 static vop_advlock_t	nfs_advlock;
150 static vop_advlockasync_t nfs_advlockasync;
151 static vop_getacl_t nfs_getacl;
152 static vop_setacl_t nfs_setacl;
153 
154 /*
155  * Global vfs data structures for nfs
156  */
157 struct vop_vector newnfs_vnodeops = {
158 	.vop_default =		&default_vnodeops,
159 	.vop_access =		nfs_access,
160 	.vop_advlock =		nfs_advlock,
161 	.vop_advlockasync =	nfs_advlockasync,
162 	.vop_close =		nfs_close,
163 	.vop_create =		nfs_create,
164 	.vop_fsync =		nfs_fsync,
165 	.vop_getattr =		nfs_getattr,
166 	.vop_getpages =		ncl_getpages,
167 	.vop_putpages =		ncl_putpages,
168 	.vop_inactive =		ncl_inactive,
169 	.vop_link =		nfs_link,
170 	.vop_lock1 = 		nfs_lock1,
171 	.vop_lookup =		nfs_lookup,
172 	.vop_mkdir =		nfs_mkdir,
173 	.vop_mknod =		nfs_mknod,
174 	.vop_open =		nfs_open,
175 	.vop_pathconf =		nfs_pathconf,
176 	.vop_print =		nfs_print,
177 	.vop_read =		nfs_read,
178 	.vop_readdir =		nfs_readdir,
179 	.vop_readlink =		nfs_readlink,
180 	.vop_reclaim =		ncl_reclaim,
181 	.vop_remove =		nfs_remove,
182 	.vop_rename =		nfs_rename,
183 	.vop_rmdir =		nfs_rmdir,
184 	.vop_setattr =		nfs_setattr,
185 	.vop_strategy =		nfs_strategy,
186 	.vop_symlink =		nfs_symlink,
187 	.vop_write =		ncl_write,
188 	.vop_getacl =		nfs_getacl,
189 	.vop_setacl =		nfs_setacl,
190 };
191 
192 struct vop_vector newnfs_fifoops = {
193 	.vop_default =		&fifo_specops,
194 	.vop_access =		nfsspec_access,
195 	.vop_close =		nfsfifo_close,
196 	.vop_fsync =		nfs_fsync,
197 	.vop_getattr =		nfs_getattr,
198 	.vop_inactive =		ncl_inactive,
199 	.vop_print =		nfs_print,
200 	.vop_read =		nfsfifo_read,
201 	.vop_reclaim =		ncl_reclaim,
202 	.vop_setattr =		nfs_setattr,
203 	.vop_write =		nfsfifo_write,
204 };
205 
206 static int nfs_mknodrpc(struct vnode *dvp, struct vnode **vpp,
207     struct componentname *cnp, struct vattr *vap);
208 static int nfs_removerpc(struct vnode *dvp, struct vnode *vp, char *name,
209     int namelen, struct ucred *cred, struct thread *td);
210 static int nfs_renamerpc(struct vnode *fdvp, struct vnode *fvp,
211     char *fnameptr, int fnamelen, struct vnode *tdvp, struct vnode *tvp,
212     char *tnameptr, int tnamelen, struct ucred *cred, struct thread *td);
213 static int nfs_renameit(struct vnode *sdvp, struct vnode *svp,
214     struct componentname *scnp, struct sillyrename *sp);
215 
216 /*
217  * Global variables
218  */
219 #define	DIRHDSIZ	(sizeof (struct dirent) - (MAXNAMLEN + 1))
220 
221 SYSCTL_DECL(_vfs_nfs);
222 
223 static int	nfsaccess_cache_timeout = NFS_MAXATTRTIMO;
224 SYSCTL_INT(_vfs_nfs, OID_AUTO, access_cache_timeout, CTLFLAG_RW,
225 	   &nfsaccess_cache_timeout, 0, "NFS ACCESS cache timeout");
226 
227 static int	nfs_prime_access_cache = 0;
228 SYSCTL_INT(_vfs_nfs, OID_AUTO, prime_access_cache, CTLFLAG_RW,
229 	   &nfs_prime_access_cache, 0,
230 	   "Prime NFS ACCESS cache when fetching attributes");
231 
232 static int	newnfs_commit_on_close = 0;
233 SYSCTL_INT(_vfs_nfs, OID_AUTO, commit_on_close, CTLFLAG_RW,
234     &newnfs_commit_on_close, 0, "write+commit on close, else only write");
235 
236 static int	nfs_clean_pages_on_close = 1;
237 SYSCTL_INT(_vfs_nfs, OID_AUTO, clean_pages_on_close, CTLFLAG_RW,
238 	   &nfs_clean_pages_on_close, 0, "NFS clean dirty pages on close");
239 
240 int newnfs_directio_enable = 0;
241 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_directio_enable, CTLFLAG_RW,
242 	   &newnfs_directio_enable, 0, "Enable NFS directio");
243 
244 int nfs_keep_dirty_on_error;
245 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_keep_dirty_on_error, CTLFLAG_RW,
246     &nfs_keep_dirty_on_error, 0, "Retry pageout if error returned");
247 
248 /*
249  * This sysctl allows other processes to mmap a file that has been opened
250  * O_DIRECT by a process.  In general, having processes mmap the file while
251  * Direct IO is in progress can lead to Data Inconsistencies.  But, we allow
252  * this by default to prevent DoS attacks - to prevent a malicious user from
253  * opening up files O_DIRECT preventing other users from mmap'ing these
254  * files.  "Protected" environments where stricter consistency guarantees are
255  * required can disable this knob.  The process that opened the file O_DIRECT
256  * cannot mmap() the file, because mmap'ed IO on an O_DIRECT open() is not
257  * meaningful.
258  */
259 int newnfs_directio_allow_mmap = 1;
260 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_directio_allow_mmap, CTLFLAG_RW,
261 	   &newnfs_directio_allow_mmap, 0, "Enable mmaped IO on file with O_DIRECT opens");
262 
263 #if 0
264 SYSCTL_INT(_vfs_nfs, OID_AUTO, access_cache_hits, CTLFLAG_RD,
265 	   &newnfsstats.accesscache_hits, 0, "NFS ACCESS cache hit count");
266 
267 SYSCTL_INT(_vfs_nfs, OID_AUTO, access_cache_misses, CTLFLAG_RD,
268 	   &newnfsstats.accesscache_misses, 0, "NFS ACCESS cache miss count");
269 #endif
270 
271 #define	NFSACCESS_ALL (NFSACCESS_READ | NFSACCESS_MODIFY		\
272 			 | NFSACCESS_EXTEND | NFSACCESS_EXECUTE	\
273 			 | NFSACCESS_DELETE | NFSACCESS_LOOKUP)
274 
275 /*
276  * SMP Locking Note :
277  * The list of locks after the description of the lock is the ordering
278  * of other locks acquired with the lock held.
279  * np->n_mtx : Protects the fields in the nfsnode.
280        VM Object Lock
281        VI_MTX (acquired indirectly)
282  * nmp->nm_mtx : Protects the fields in the nfsmount.
283        rep->r_mtx
284  * ncl_iod_mutex : Global lock, protects shared nfsiod state.
285  * nfs_reqq_mtx : Global lock, protects the nfs_reqq list.
286        nmp->nm_mtx
287        rep->r_mtx
288  * rep->r_mtx : Protects the fields in an nfsreq.
289  */
290 
291 static int
292 nfs34_access_otw(struct vnode *vp, int wmode, struct thread *td,
293     struct ucred *cred, u_int32_t *retmode)
294 {
295 	int error = 0, attrflag, i, lrupos;
296 	u_int32_t rmode;
297 	struct nfsnode *np = VTONFS(vp);
298 	struct nfsvattr nfsva;
299 
300 	error = nfsrpc_accessrpc(vp, wmode, cred, td, &nfsva, &attrflag,
301 	    &rmode, NULL);
302 	if (attrflag)
303 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
304 	if (!error) {
305 		lrupos = 0;
306 		mtx_lock(&np->n_mtx);
307 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++) {
308 			if (np->n_accesscache[i].uid == cred->cr_uid) {
309 				np->n_accesscache[i].mode = rmode;
310 				np->n_accesscache[i].stamp = time_second;
311 				break;
312 			}
313 			if (i > 0 && np->n_accesscache[i].stamp <
314 			    np->n_accesscache[lrupos].stamp)
315 				lrupos = i;
316 		}
317 		if (i == NFS_ACCESSCACHESIZE) {
318 			np->n_accesscache[lrupos].uid = cred->cr_uid;
319 			np->n_accesscache[lrupos].mode = rmode;
320 			np->n_accesscache[lrupos].stamp = time_second;
321 		}
322 		mtx_unlock(&np->n_mtx);
323 		if (retmode != NULL)
324 			*retmode = rmode;
325 		KDTRACE_NFS_ACCESSCACHE_LOAD_DONE(vp, cred->cr_uid, rmode, 0);
326 	} else if (NFS_ISV4(vp)) {
327 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
328 	}
329 #ifdef KDTRACE_HOOKS
330 	if (error != 0)
331 		KDTRACE_NFS_ACCESSCACHE_LOAD_DONE(vp, cred->cr_uid, 0,
332 		    error);
333 #endif
334 	return (error);
335 }
336 
337 /*
338  * nfs access vnode op.
339  * For nfs version 2, just return ok. File accesses may fail later.
340  * For nfs version 3, use the access rpc to check accessibility. If file modes
341  * are changed on the server, accesses might still fail later.
342  */
343 static int
344 nfs_access(struct vop_access_args *ap)
345 {
346 	struct vnode *vp = ap->a_vp;
347 	int error = 0, i, gotahit;
348 	u_int32_t mode, wmode, rmode;
349 	int v34 = NFS_ISV34(vp);
350 	struct nfsnode *np = VTONFS(vp);
351 
352 	/*
353 	 * Disallow write attempts on filesystems mounted read-only;
354 	 * unless the file is a socket, fifo, or a block or character
355 	 * device resident on the filesystem.
356 	 */
357 	if ((ap->a_accmode & (VWRITE | VAPPEND | VWRITE_NAMED_ATTRS |
358 	    VDELETE_CHILD | VWRITE_ATTRIBUTES | VDELETE | VWRITE_ACL |
359 	    VWRITE_OWNER)) != 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) != 0) {
360 		switch (vp->v_type) {
361 		case VREG:
362 		case VDIR:
363 		case VLNK:
364 			return (EROFS);
365 		default:
366 			break;
367 		}
368 	}
369 	/*
370 	 * For nfs v3 or v4, check to see if we have done this recently, and if
371 	 * so return our cached result instead of making an ACCESS call.
372 	 * If not, do an access rpc, otherwise you are stuck emulating
373 	 * ufs_access() locally using the vattr. This may not be correct,
374 	 * since the server may apply other access criteria such as
375 	 * client uid-->server uid mapping that we do not know about.
376 	 */
377 	if (v34) {
378 		if (ap->a_accmode & VREAD)
379 			mode = NFSACCESS_READ;
380 		else
381 			mode = 0;
382 		if (vp->v_type != VDIR) {
383 			if (ap->a_accmode & VWRITE)
384 				mode |= (NFSACCESS_MODIFY | NFSACCESS_EXTEND);
385 			if (ap->a_accmode & VAPPEND)
386 				mode |= NFSACCESS_EXTEND;
387 			if (ap->a_accmode & VEXEC)
388 				mode |= NFSACCESS_EXECUTE;
389 			if (ap->a_accmode & VDELETE)
390 				mode |= NFSACCESS_DELETE;
391 		} else {
392 			if (ap->a_accmode & VWRITE)
393 				mode |= (NFSACCESS_MODIFY | NFSACCESS_EXTEND);
394 			if (ap->a_accmode & VAPPEND)
395 				mode |= NFSACCESS_EXTEND;
396 			if (ap->a_accmode & VEXEC)
397 				mode |= NFSACCESS_LOOKUP;
398 			if (ap->a_accmode & VDELETE)
399 				mode |= NFSACCESS_DELETE;
400 			if (ap->a_accmode & VDELETE_CHILD)
401 				mode |= NFSACCESS_MODIFY;
402 		}
403 		/* XXX safety belt, only make blanket request if caching */
404 		if (nfsaccess_cache_timeout > 0) {
405 			wmode = NFSACCESS_READ | NFSACCESS_MODIFY |
406 				NFSACCESS_EXTEND | NFSACCESS_EXECUTE |
407 				NFSACCESS_DELETE | NFSACCESS_LOOKUP;
408 		} else {
409 			wmode = mode;
410 		}
411 
412 		/*
413 		 * Does our cached result allow us to give a definite yes to
414 		 * this request?
415 		 */
416 		gotahit = 0;
417 		mtx_lock(&np->n_mtx);
418 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++) {
419 			if (ap->a_cred->cr_uid == np->n_accesscache[i].uid) {
420 			    if (time_second < (np->n_accesscache[i].stamp
421 				+ nfsaccess_cache_timeout) &&
422 				(np->n_accesscache[i].mode & mode) == mode) {
423 				NFSINCRGLOBAL(newnfsstats.accesscache_hits);
424 				gotahit = 1;
425 			    }
426 			    break;
427 			}
428 		}
429 		mtx_unlock(&np->n_mtx);
430 #ifdef KDTRACE_HOOKS
431 		if (gotahit != 0)
432 			KDTRACE_NFS_ACCESSCACHE_GET_HIT(vp,
433 			    ap->a_cred->cr_uid, mode);
434 		else
435 			KDTRACE_NFS_ACCESSCACHE_GET_MISS(vp,
436 			    ap->a_cred->cr_uid, mode);
437 #endif
438 		if (gotahit == 0) {
439 			/*
440 			 * Either a no, or a don't know.  Go to the wire.
441 			 */
442 			NFSINCRGLOBAL(newnfsstats.accesscache_misses);
443 		        error = nfs34_access_otw(vp, wmode, ap->a_td,
444 			    ap->a_cred, &rmode);
445 			if (!error &&
446 			    (rmode & mode) != mode)
447 				error = EACCES;
448 		}
449 		return (error);
450 	} else {
451 		if ((error = nfsspec_access(ap)) != 0) {
452 			return (error);
453 		}
454 		/*
455 		 * Attempt to prevent a mapped root from accessing a file
456 		 * which it shouldn't.  We try to read a byte from the file
457 		 * if the user is root and the file is not zero length.
458 		 * After calling nfsspec_access, we should have the correct
459 		 * file size cached.
460 		 */
461 		mtx_lock(&np->n_mtx);
462 		if (ap->a_cred->cr_uid == 0 && (ap->a_accmode & VREAD)
463 		    && VTONFS(vp)->n_size > 0) {
464 			struct iovec aiov;
465 			struct uio auio;
466 			char buf[1];
467 
468 			mtx_unlock(&np->n_mtx);
469 			aiov.iov_base = buf;
470 			aiov.iov_len = 1;
471 			auio.uio_iov = &aiov;
472 			auio.uio_iovcnt = 1;
473 			auio.uio_offset = 0;
474 			auio.uio_resid = 1;
475 			auio.uio_segflg = UIO_SYSSPACE;
476 			auio.uio_rw = UIO_READ;
477 			auio.uio_td = ap->a_td;
478 
479 			if (vp->v_type == VREG)
480 				error = ncl_readrpc(vp, &auio, ap->a_cred);
481 			else if (vp->v_type == VDIR) {
482 				char* bp;
483 				bp = malloc(NFS_DIRBLKSIZ, M_TEMP, M_WAITOK);
484 				aiov.iov_base = bp;
485 				aiov.iov_len = auio.uio_resid = NFS_DIRBLKSIZ;
486 				error = ncl_readdirrpc(vp, &auio, ap->a_cred,
487 				    ap->a_td);
488 				free(bp, M_TEMP);
489 			} else if (vp->v_type == VLNK)
490 				error = ncl_readlinkrpc(vp, &auio, ap->a_cred);
491 			else
492 				error = EACCES;
493 		} else
494 			mtx_unlock(&np->n_mtx);
495 		return (error);
496 	}
497 }
498 
499 
500 /*
501  * nfs open vnode op
502  * Check to see if the type is ok
503  * and that deletion is not in progress.
504  * For paged in text files, you will need to flush the page cache
505  * if consistency is lost.
506  */
507 /* ARGSUSED */
508 static int
509 nfs_open(struct vop_open_args *ap)
510 {
511 	struct vnode *vp = ap->a_vp;
512 	struct nfsnode *np = VTONFS(vp);
513 	struct vattr vattr;
514 	int error;
515 	int fmode = ap->a_mode;
516 	struct ucred *cred;
517 
518 	if (vp->v_type != VREG && vp->v_type != VDIR && vp->v_type != VLNK)
519 		return (EOPNOTSUPP);
520 
521 	/*
522 	 * For NFSv4, we need to do the Open Op before cache validation,
523 	 * so that we conform to RFC3530 Sec. 9.3.1.
524 	 */
525 	if (NFS_ISV4(vp)) {
526 		error = nfsrpc_open(vp, fmode, ap->a_cred, ap->a_td);
527 		if (error) {
528 			error = nfscl_maperr(ap->a_td, error, (uid_t)0,
529 			    (gid_t)0);
530 			return (error);
531 		}
532 	}
533 
534 	/*
535 	 * Now, if this Open will be doing reading, re-validate/flush the
536 	 * cache, so that Close/Open coherency is maintained.
537 	 */
538 	mtx_lock(&np->n_mtx);
539 	if (np->n_flag & NMODIFIED) {
540 		mtx_unlock(&np->n_mtx);
541 		error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
542 		if (error == EINTR || error == EIO) {
543 			if (NFS_ISV4(vp))
544 				(void) nfsrpc_close(vp, 0, ap->a_td);
545 			return (error);
546 		}
547 		mtx_lock(&np->n_mtx);
548 		np->n_attrstamp = 0;
549 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
550 		if (vp->v_type == VDIR)
551 			np->n_direofoffset = 0;
552 		mtx_unlock(&np->n_mtx);
553 		error = VOP_GETATTR(vp, &vattr, ap->a_cred);
554 		if (error) {
555 			if (NFS_ISV4(vp))
556 				(void) nfsrpc_close(vp, 0, ap->a_td);
557 			return (error);
558 		}
559 		mtx_lock(&np->n_mtx);
560 		np->n_mtime = vattr.va_mtime;
561 		if (NFS_ISV4(vp))
562 			np->n_change = vattr.va_filerev;
563 	} else {
564 		mtx_unlock(&np->n_mtx);
565 		error = VOP_GETATTR(vp, &vattr, ap->a_cred);
566 		if (error) {
567 			if (NFS_ISV4(vp))
568 				(void) nfsrpc_close(vp, 0, ap->a_td);
569 			return (error);
570 		}
571 		mtx_lock(&np->n_mtx);
572 		if ((NFS_ISV4(vp) && np->n_change != vattr.va_filerev) ||
573 		    NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime)) {
574 			if (vp->v_type == VDIR)
575 				np->n_direofoffset = 0;
576 			mtx_unlock(&np->n_mtx);
577 			error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
578 			if (error == EINTR || error == EIO) {
579 				if (NFS_ISV4(vp))
580 					(void) nfsrpc_close(vp, 0, ap->a_td);
581 				return (error);
582 			}
583 			mtx_lock(&np->n_mtx);
584 			np->n_mtime = vattr.va_mtime;
585 			if (NFS_ISV4(vp))
586 				np->n_change = vattr.va_filerev;
587 		}
588 	}
589 
590 	/*
591 	 * If the object has >= 1 O_DIRECT active opens, we disable caching.
592 	 */
593 	if (newnfs_directio_enable && (fmode & O_DIRECT) &&
594 	    (vp->v_type == VREG)) {
595 		if (np->n_directio_opens == 0) {
596 			mtx_unlock(&np->n_mtx);
597 			error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
598 			if (error) {
599 				if (NFS_ISV4(vp))
600 					(void) nfsrpc_close(vp, 0, ap->a_td);
601 				return (error);
602 			}
603 			mtx_lock(&np->n_mtx);
604 			np->n_flag |= NNONCACHE;
605 		}
606 		np->n_directio_opens++;
607 	}
608 
609 	/*
610 	 * If this is an open for writing, capture a reference to the
611 	 * credentials, so they can be used by ncl_putpages(). Using
612 	 * these write credentials is preferable to the credentials of
613 	 * whatever thread happens to be doing the VOP_PUTPAGES() since
614 	 * the write RPCs are less likely to fail with EACCES.
615 	 */
616 	if ((fmode & FWRITE) != 0) {
617 		cred = np->n_writecred;
618 		np->n_writecred = crhold(ap->a_cred);
619 	} else
620 		cred = NULL;
621 	mtx_unlock(&np->n_mtx);
622 	if (cred != NULL)
623 		crfree(cred);
624 	vnode_create_vobject(vp, vattr.va_size, ap->a_td);
625 	return (0);
626 }
627 
628 /*
629  * nfs close vnode op
630  * What an NFS client should do upon close after writing is a debatable issue.
631  * Most NFS clients push delayed writes to the server upon close, basically for
632  * two reasons:
633  * 1 - So that any write errors may be reported back to the client process
634  *     doing the close system call. By far the two most likely errors are
635  *     NFSERR_NOSPC and NFSERR_DQUOT to indicate space allocation failure.
636  * 2 - To put a worst case upper bound on cache inconsistency between
637  *     multiple clients for the file.
638  * There is also a consistency problem for Version 2 of the protocol w.r.t.
639  * not being able to tell if other clients are writing a file concurrently,
640  * since there is no way of knowing if the changed modify time in the reply
641  * is only due to the write for this client.
642  * (NFS Version 3 provides weak cache consistency data in the reply that
643  *  should be sufficient to detect and handle this case.)
644  *
645  * The current code does the following:
646  * for NFS Version 2 - play it safe and flush/invalidate all dirty buffers
647  * for NFS Version 3 - flush dirty buffers to the server but don't invalidate
648  *                     or commit them (this satisfies 1 and 2 except for the
649  *                     case where the server crashes after this close but
650  *                     before the commit RPC, which is felt to be "good
651  *                     enough". Changing the last argument to ncl_flush() to
652  *                     a 1 would force a commit operation, if it is felt a
653  *                     commit is necessary now.
654  * for NFS Version 4 - flush the dirty buffers and commit them, if
655  *		       nfscl_mustflush() says this is necessary.
656  *                     It is necessary if there is no write delegation held,
657  *                     in order to satisfy open/close coherency.
658  *                     If the file isn't cached on local stable storage,
659  *                     it may be necessary in order to detect "out of space"
660  *                     errors from the server, if the write delegation
661  *                     issued by the server doesn't allow the file to grow.
662  */
663 /* ARGSUSED */
664 static int
665 nfs_close(struct vop_close_args *ap)
666 {
667 	struct vnode *vp = ap->a_vp;
668 	struct nfsnode *np = VTONFS(vp);
669 	struct nfsvattr nfsva;
670 	struct ucred *cred;
671 	int error = 0, ret, localcred = 0;
672 	int fmode = ap->a_fflag;
673 
674 	if ((vp->v_mount->mnt_kern_flag & MNTK_UNMOUNTF))
675 		return (0);
676 	/*
677 	 * During shutdown, a_cred isn't valid, so just use root.
678 	 */
679 	if (ap->a_cred == NOCRED) {
680 		cred = newnfs_getcred();
681 		localcred = 1;
682 	} else {
683 		cred = ap->a_cred;
684 	}
685 	if (vp->v_type == VREG) {
686 	    /*
687 	     * Examine and clean dirty pages, regardless of NMODIFIED.
688 	     * This closes a major hole in close-to-open consistency.
689 	     * We want to push out all dirty pages (and buffers) on
690 	     * close, regardless of whether they were dirtied by
691 	     * mmap'ed writes or via write().
692 	     */
693 	    if (nfs_clean_pages_on_close && vp->v_object) {
694 		VM_OBJECT_LOCK(vp->v_object);
695 		vm_object_page_clean(vp->v_object, 0, 0, 0);
696 		VM_OBJECT_UNLOCK(vp->v_object);
697 	    }
698 	    mtx_lock(&np->n_mtx);
699 	    if (np->n_flag & NMODIFIED) {
700 		mtx_unlock(&np->n_mtx);
701 		if (NFS_ISV3(vp)) {
702 		    /*
703 		     * Under NFSv3 we have dirty buffers to dispose of.  We
704 		     * must flush them to the NFS server.  We have the option
705 		     * of waiting all the way through the commit rpc or just
706 		     * waiting for the initial write.  The default is to only
707 		     * wait through the initial write so the data is in the
708 		     * server's cache, which is roughly similar to the state
709 		     * a standard disk subsystem leaves the file in on close().
710 		     *
711 		     * We cannot clear the NMODIFIED bit in np->n_flag due to
712 		     * potential races with other processes, and certainly
713 		     * cannot clear it if we don't commit.
714 		     * These races occur when there is no longer the old
715 		     * traditional vnode locking implemented for Vnode Ops.
716 		     */
717 		    int cm = newnfs_commit_on_close ? 1 : 0;
718 		    error = ncl_flush(vp, MNT_WAIT, cred, ap->a_td, cm, 0);
719 		    /* np->n_flag &= ~NMODIFIED; */
720 		} else if (NFS_ISV4(vp)) {
721 			if (nfscl_mustflush(vp) != 0) {
722 				int cm = newnfs_commit_on_close ? 1 : 0;
723 				error = ncl_flush(vp, MNT_WAIT, cred, ap->a_td,
724 				    cm, 0);
725 				/*
726 				 * as above w.r.t races when clearing
727 				 * NMODIFIED.
728 				 * np->n_flag &= ~NMODIFIED;
729 				 */
730 			}
731 		} else
732 		    error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
733 		mtx_lock(&np->n_mtx);
734 	    }
735  	    /*
736  	     * Invalidate the attribute cache in all cases.
737  	     * An open is going to fetch fresh attrs any way, other procs
738  	     * on this node that have file open will be forced to do an
739  	     * otw attr fetch, but this is safe.
740 	     * --> A user found that their RPC count dropped by 20% when
741 	     *     this was commented out and I can't see any requirement
742 	     *     for it, so I've disabled it when negative lookups are
743 	     *     enabled. (What does this have to do with negative lookup
744 	     *     caching? Well nothing, except it was reported by the
745 	     *     same user that needed negative lookup caching and I wanted
746 	     *     there to be a way to disable it to see if it
747 	     *     is the cause of some caching/coherency issue that might
748 	     *     crop up.)
749  	     */
750 	    if (VFSTONFS(vp->v_mount)->nm_negnametimeo == 0) {
751 		    np->n_attrstamp = 0;
752 		    KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
753 	    }
754 	    if (np->n_flag & NWRITEERR) {
755 		np->n_flag &= ~NWRITEERR;
756 		error = np->n_error;
757 	    }
758 	    mtx_unlock(&np->n_mtx);
759 	}
760 
761 	if (NFS_ISV4(vp)) {
762 		/*
763 		 * Get attributes so "change" is up to date.
764 		 */
765 		if (error == 0 && nfscl_mustflush(vp) != 0) {
766 			ret = nfsrpc_getattr(vp, cred, ap->a_td, &nfsva,
767 			    NULL);
768 			if (!ret) {
769 				np->n_change = nfsva.na_filerev;
770 				(void) nfscl_loadattrcache(&vp, &nfsva, NULL,
771 				    NULL, 0, 0);
772 			}
773 		}
774 
775 		/*
776 		 * and do the close.
777 		 */
778 		ret = nfsrpc_close(vp, 0, ap->a_td);
779 		if (!error && ret)
780 			error = ret;
781 		if (error)
782 			error = nfscl_maperr(ap->a_td, error, (uid_t)0,
783 			    (gid_t)0);
784 	}
785 	if (newnfs_directio_enable)
786 		KASSERT((np->n_directio_asyncwr == 0),
787 			("nfs_close: dirty unflushed (%d) directio buffers\n",
788 			 np->n_directio_asyncwr));
789 	if (newnfs_directio_enable && (fmode & O_DIRECT) && (vp->v_type == VREG)) {
790 		mtx_lock(&np->n_mtx);
791 		KASSERT((np->n_directio_opens > 0),
792 			("nfs_close: unexpectedly value (0) of n_directio_opens\n"));
793 		np->n_directio_opens--;
794 		if (np->n_directio_opens == 0)
795 			np->n_flag &= ~NNONCACHE;
796 		mtx_unlock(&np->n_mtx);
797 	}
798 	if (localcred)
799 		NFSFREECRED(cred);
800 	return (error);
801 }
802 
803 /*
804  * nfs getattr call from vfs.
805  */
806 static int
807 nfs_getattr(struct vop_getattr_args *ap)
808 {
809 	struct vnode *vp = ap->a_vp;
810 	struct thread *td = curthread;	/* XXX */
811 	struct nfsnode *np = VTONFS(vp);
812 	int error = 0;
813 	struct nfsvattr nfsva;
814 	struct vattr *vap = ap->a_vap;
815 	struct vattr vattr;
816 
817 	/*
818 	 * Update local times for special files.
819 	 */
820 	mtx_lock(&np->n_mtx);
821 	if (np->n_flag & (NACC | NUPD))
822 		np->n_flag |= NCHG;
823 	mtx_unlock(&np->n_mtx);
824 	/*
825 	 * First look in the cache.
826 	 */
827 	if (ncl_getattrcache(vp, &vattr) == 0) {
828 		vap->va_type = vattr.va_type;
829 		vap->va_mode = vattr.va_mode;
830 		vap->va_nlink = vattr.va_nlink;
831 		vap->va_uid = vattr.va_uid;
832 		vap->va_gid = vattr.va_gid;
833 		vap->va_fsid = vattr.va_fsid;
834 		vap->va_fileid = vattr.va_fileid;
835 		vap->va_size = vattr.va_size;
836 		vap->va_blocksize = vattr.va_blocksize;
837 		vap->va_atime = vattr.va_atime;
838 		vap->va_mtime = vattr.va_mtime;
839 		vap->va_ctime = vattr.va_ctime;
840 		vap->va_gen = vattr.va_gen;
841 		vap->va_flags = vattr.va_flags;
842 		vap->va_rdev = vattr.va_rdev;
843 		vap->va_bytes = vattr.va_bytes;
844 		vap->va_filerev = vattr.va_filerev;
845 		/*
846 		 * Get the local modify time for the case of a write
847 		 * delegation.
848 		 */
849 		nfscl_deleggetmodtime(vp, &vap->va_mtime);
850 		return (0);
851 	}
852 
853 	if (NFS_ISV34(vp) && nfs_prime_access_cache &&
854 	    nfsaccess_cache_timeout > 0) {
855 		NFSINCRGLOBAL(newnfsstats.accesscache_misses);
856 		nfs34_access_otw(vp, NFSACCESS_ALL, td, ap->a_cred, NULL);
857 		if (ncl_getattrcache(vp, ap->a_vap) == 0) {
858 			nfscl_deleggetmodtime(vp, &ap->a_vap->va_mtime);
859 			return (0);
860 		}
861 	}
862 	error = nfsrpc_getattr(vp, ap->a_cred, td, &nfsva, NULL);
863 	if (!error)
864 		error = nfscl_loadattrcache(&vp, &nfsva, vap, NULL, 0, 0);
865 	if (!error) {
866 		/*
867 		 * Get the local modify time for the case of a write
868 		 * delegation.
869 		 */
870 		nfscl_deleggetmodtime(vp, &vap->va_mtime);
871 	} else if (NFS_ISV4(vp)) {
872 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
873 	}
874 	return (error);
875 }
876 
877 /*
878  * nfs setattr call.
879  */
880 static int
881 nfs_setattr(struct vop_setattr_args *ap)
882 {
883 	struct vnode *vp = ap->a_vp;
884 	struct nfsnode *np = VTONFS(vp);
885 	struct thread *td = curthread;	/* XXX */
886 	struct vattr *vap = ap->a_vap;
887 	int error = 0;
888 	u_quad_t tsize;
889 
890 #ifndef nolint
891 	tsize = (u_quad_t)0;
892 #endif
893 
894 	/*
895 	 * Setting of flags and marking of atimes are not supported.
896 	 */
897 	if (vap->va_flags != VNOVAL)
898 		return (EOPNOTSUPP);
899 
900 	/*
901 	 * Disallow write attempts if the filesystem is mounted read-only.
902 	 */
903   	if ((vap->va_flags != VNOVAL || vap->va_uid != (uid_t)VNOVAL ||
904 	    vap->va_gid != (gid_t)VNOVAL || vap->va_atime.tv_sec != VNOVAL ||
905 	    vap->va_mtime.tv_sec != VNOVAL || vap->va_mode != (mode_t)VNOVAL) &&
906 	    (vp->v_mount->mnt_flag & MNT_RDONLY))
907 		return (EROFS);
908 	if (vap->va_size != VNOVAL) {
909  		switch (vp->v_type) {
910  		case VDIR:
911  			return (EISDIR);
912  		case VCHR:
913  		case VBLK:
914  		case VSOCK:
915  		case VFIFO:
916 			if (vap->va_mtime.tv_sec == VNOVAL &&
917 			    vap->va_atime.tv_sec == VNOVAL &&
918 			    vap->va_mode == (mode_t)VNOVAL &&
919 			    vap->va_uid == (uid_t)VNOVAL &&
920 			    vap->va_gid == (gid_t)VNOVAL)
921 				return (0);
922  			vap->va_size = VNOVAL;
923  			break;
924  		default:
925 			/*
926 			 * Disallow write attempts if the filesystem is
927 			 * mounted read-only.
928 			 */
929 			if (vp->v_mount->mnt_flag & MNT_RDONLY)
930 				return (EROFS);
931 			/*
932 			 *  We run vnode_pager_setsize() early (why?),
933 			 * we must set np->n_size now to avoid vinvalbuf
934 			 * V_SAVE races that might setsize a lower
935 			 * value.
936 			 */
937 			mtx_lock(&np->n_mtx);
938 			tsize = np->n_size;
939 			mtx_unlock(&np->n_mtx);
940 			error = ncl_meta_setsize(vp, ap->a_cred, td,
941 			    vap->va_size);
942 			mtx_lock(&np->n_mtx);
943  			if (np->n_flag & NMODIFIED) {
944 			    tsize = np->n_size;
945 			    mtx_unlock(&np->n_mtx);
946  			    if (vap->va_size == 0)
947  				error = ncl_vinvalbuf(vp, 0, td, 1);
948  			    else
949  				error = ncl_vinvalbuf(vp, V_SAVE, td, 1);
950  			    if (error) {
951 				vnode_pager_setsize(vp, tsize);
952 				return (error);
953 			    }
954 			    /*
955 			     * Call nfscl_delegmodtime() to set the modify time
956 			     * locally, as required.
957 			     */
958 			    nfscl_delegmodtime(vp);
959  			} else
960 			    mtx_unlock(&np->n_mtx);
961 			/*
962 			 * np->n_size has already been set to vap->va_size
963 			 * in ncl_meta_setsize(). We must set it again since
964 			 * nfs_loadattrcache() could be called through
965 			 * ncl_meta_setsize() and could modify np->n_size.
966 			 */
967 			mtx_lock(&np->n_mtx);
968  			np->n_vattr.na_size = np->n_size = vap->va_size;
969 			mtx_unlock(&np->n_mtx);
970   		};
971   	} else {
972 		mtx_lock(&np->n_mtx);
973 		if ((vap->va_mtime.tv_sec != VNOVAL || vap->va_atime.tv_sec != VNOVAL) &&
974 		    (np->n_flag & NMODIFIED) && vp->v_type == VREG) {
975 			mtx_unlock(&np->n_mtx);
976 			if ((error = ncl_vinvalbuf(vp, V_SAVE, td, 1)) != 0 &&
977 			    (error == EINTR || error == EIO))
978 				return (error);
979 		} else
980 			mtx_unlock(&np->n_mtx);
981 	}
982 	error = nfs_setattrrpc(vp, vap, ap->a_cred, td);
983 	if (error && vap->va_size != VNOVAL) {
984 		mtx_lock(&np->n_mtx);
985 		np->n_size = np->n_vattr.na_size = tsize;
986 		vnode_pager_setsize(vp, tsize);
987 		mtx_unlock(&np->n_mtx);
988 	}
989 	return (error);
990 }
991 
992 /*
993  * Do an nfs setattr rpc.
994  */
995 static int
996 nfs_setattrrpc(struct vnode *vp, struct vattr *vap, struct ucred *cred,
997     struct thread *td)
998 {
999 	struct nfsnode *np = VTONFS(vp);
1000 	int error, ret, attrflag, i;
1001 	struct nfsvattr nfsva;
1002 
1003 	if (NFS_ISV34(vp)) {
1004 		mtx_lock(&np->n_mtx);
1005 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++)
1006 			np->n_accesscache[i].stamp = 0;
1007 		np->n_flag |= NDELEGMOD;
1008 		mtx_unlock(&np->n_mtx);
1009 		KDTRACE_NFS_ACCESSCACHE_FLUSH_DONE(vp);
1010 	}
1011 	error = nfsrpc_setattr(vp, vap, NULL, cred, td, &nfsva, &attrflag,
1012 	    NULL);
1013 	if (attrflag) {
1014 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
1015 		if (ret && !error)
1016 			error = ret;
1017 	}
1018 	if (error && NFS_ISV4(vp))
1019 		error = nfscl_maperr(td, error, vap->va_uid, vap->va_gid);
1020 	return (error);
1021 }
1022 
1023 /*
1024  * nfs lookup call, one step at a time...
1025  * First look in cache
1026  * If not found, unlock the directory nfsnode and do the rpc
1027  */
1028 static int
1029 nfs_lookup(struct vop_lookup_args *ap)
1030 {
1031 	struct componentname *cnp = ap->a_cnp;
1032 	struct vnode *dvp = ap->a_dvp;
1033 	struct vnode **vpp = ap->a_vpp;
1034 	struct mount *mp = dvp->v_mount;
1035 	int flags = cnp->cn_flags;
1036 	struct vnode *newvp;
1037 	struct nfsmount *nmp;
1038 	struct nfsnode *np, *newnp;
1039 	int error = 0, attrflag, dattrflag, ltype, ncticks;
1040 	struct thread *td = cnp->cn_thread;
1041 	struct nfsfh *nfhp;
1042 	struct nfsvattr dnfsva, nfsva;
1043 	struct vattr vattr;
1044 	struct timespec nctime;
1045 
1046 	*vpp = NULLVP;
1047 	if ((flags & ISLASTCN) && (mp->mnt_flag & MNT_RDONLY) &&
1048 	    (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
1049 		return (EROFS);
1050 	if (dvp->v_type != VDIR)
1051 		return (ENOTDIR);
1052 	nmp = VFSTONFS(mp);
1053 	np = VTONFS(dvp);
1054 
1055 	/* For NFSv4, wait until any remove is done. */
1056 	mtx_lock(&np->n_mtx);
1057 	while (NFSHASNFSV4(nmp) && (np->n_flag & NREMOVEINPROG)) {
1058 		np->n_flag |= NREMOVEWANT;
1059 		(void) msleep((caddr_t)np, &np->n_mtx, PZERO, "nfslkup", 0);
1060 	}
1061 	mtx_unlock(&np->n_mtx);
1062 
1063 	if ((error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, td)) != 0)
1064 		return (error);
1065 	error = cache_lookup(dvp, vpp, cnp, &nctime, &ncticks);
1066 	if (error > 0 && error != ENOENT)
1067 		return (error);
1068 	if (error == -1) {
1069 		/*
1070 		 * Lookups of "." are special and always return the
1071 		 * current directory.  cache_lookup() already handles
1072 		 * associated locking bookkeeping, etc.
1073 		 */
1074 		if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
1075 			/* XXX: Is this really correct? */
1076 			if (cnp->cn_nameiop != LOOKUP &&
1077 			    (flags & ISLASTCN))
1078 				cnp->cn_flags |= SAVENAME;
1079 			return (0);
1080 		}
1081 
1082 		/*
1083 		 * We only accept a positive hit in the cache if the
1084 		 * change time of the file matches our cached copy.
1085 		 * Otherwise, we discard the cache entry and fallback
1086 		 * to doing a lookup RPC.  We also only trust cache
1087 		 * entries for less than nm_nametimeo seconds.
1088 		 *
1089 		 * To better handle stale file handles and attributes,
1090 		 * clear the attribute cache of this node if it is a
1091 		 * leaf component, part of an open() call, and not
1092 		 * locally modified before fetching the attributes.
1093 		 * This should allow stale file handles to be detected
1094 		 * here where we can fall back to a LOOKUP RPC to
1095 		 * recover rather than having nfs_open() detect the
1096 		 * stale file handle and failing open(2) with ESTALE.
1097 		 */
1098 		newvp = *vpp;
1099 		newnp = VTONFS(newvp);
1100 		if (!(nmp->nm_flag & NFSMNT_NOCTO) &&
1101 		    (flags & (ISLASTCN | ISOPEN)) == (ISLASTCN | ISOPEN) &&
1102 		    !(newnp->n_flag & NMODIFIED)) {
1103 			mtx_lock(&newnp->n_mtx);
1104 			newnp->n_attrstamp = 0;
1105 			KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(newvp);
1106 			mtx_unlock(&newnp->n_mtx);
1107 		}
1108 		if (nfscl_nodeleg(newvp, 0) == 0 ||
1109 		    ((u_int)(ticks - ncticks) < (nmp->nm_nametimeo * hz) &&
1110 		    VOP_GETATTR(newvp, &vattr, cnp->cn_cred) == 0 &&
1111 		    timespeccmp(&vattr.va_ctime, &nctime, ==))) {
1112 			NFSINCRGLOBAL(newnfsstats.lookupcache_hits);
1113 			if (cnp->cn_nameiop != LOOKUP &&
1114 			    (flags & ISLASTCN))
1115 				cnp->cn_flags |= SAVENAME;
1116 			return (0);
1117 		}
1118 		cache_purge(newvp);
1119 		if (dvp != newvp)
1120 			vput(newvp);
1121 		else
1122 			vrele(newvp);
1123 		*vpp = NULLVP;
1124 	} else if (error == ENOENT) {
1125 		if (dvp->v_iflag & VI_DOOMED)
1126 			return (ENOENT);
1127 		/*
1128 		 * We only accept a negative hit in the cache if the
1129 		 * modification time of the parent directory matches
1130 		 * the cached copy in the name cache entry.
1131 		 * Otherwise, we discard all of the negative cache
1132 		 * entries for this directory.  We also only trust
1133 		 * negative cache entries for up to nm_negnametimeo
1134 		 * seconds.
1135 		 */
1136 		if ((u_int)(ticks - ncticks) < (nmp->nm_negnametimeo * hz) &&
1137 		    VOP_GETATTR(dvp, &vattr, cnp->cn_cred) == 0 &&
1138 		    timespeccmp(&vattr.va_mtime, &nctime, ==)) {
1139 			NFSINCRGLOBAL(newnfsstats.lookupcache_hits);
1140 			return (ENOENT);
1141 		}
1142 		cache_purge_negative(dvp);
1143 	}
1144 
1145 	error = 0;
1146 	newvp = NULLVP;
1147 	NFSINCRGLOBAL(newnfsstats.lookupcache_misses);
1148 	error = nfsrpc_lookup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
1149 	    cnp->cn_cred, td, &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag,
1150 	    NULL);
1151 	if (dattrflag)
1152 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
1153 	if (error) {
1154 		if (newvp != NULLVP) {
1155 			vput(newvp);
1156 			*vpp = NULLVP;
1157 		}
1158 
1159 		if (error != ENOENT) {
1160 			if (NFS_ISV4(dvp))
1161 				error = nfscl_maperr(td, error, (uid_t)0,
1162 				    (gid_t)0);
1163 			return (error);
1164 		}
1165 
1166 		/* The requested file was not found. */
1167 		if ((cnp->cn_nameiop == CREATE || cnp->cn_nameiop == RENAME) &&
1168 		    (flags & ISLASTCN)) {
1169 			/*
1170 			 * XXX: UFS does a full VOP_ACCESS(dvp,
1171 			 * VWRITE) here instead of just checking
1172 			 * MNT_RDONLY.
1173 			 */
1174 			if (mp->mnt_flag & MNT_RDONLY)
1175 				return (EROFS);
1176 			cnp->cn_flags |= SAVENAME;
1177 			return (EJUSTRETURN);
1178 		}
1179 
1180 		if ((cnp->cn_flags & MAKEENTRY) && cnp->cn_nameiop != CREATE &&
1181 		    dattrflag) {
1182 			/*
1183 			 * Cache the modification time of the parent
1184 			 * directory from the post-op attributes in
1185 			 * the name cache entry.  The negative cache
1186 			 * entry will be ignored once the directory
1187 			 * has changed.  Don't bother adding the entry
1188 			 * if the directory has already changed.
1189 			 */
1190 			mtx_lock(&np->n_mtx);
1191 			if (timespeccmp(&np->n_vattr.na_mtime,
1192 			    &dnfsva.na_mtime, ==)) {
1193 				mtx_unlock(&np->n_mtx);
1194 				cache_enter_time(dvp, NULL, cnp,
1195 				    &dnfsva.na_mtime, NULL);
1196 			} else
1197 				mtx_unlock(&np->n_mtx);
1198 		}
1199 		return (ENOENT);
1200 	}
1201 
1202 	/*
1203 	 * Handle RENAME case...
1204 	 */
1205 	if (cnp->cn_nameiop == RENAME && (flags & ISLASTCN)) {
1206 		if (NFS_CMPFH(np, nfhp->nfh_fh, nfhp->nfh_len)) {
1207 			FREE((caddr_t)nfhp, M_NFSFH);
1208 			return (EISDIR);
1209 		}
1210 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np, NULL,
1211 		    LK_EXCLUSIVE);
1212 		if (error)
1213 			return (error);
1214 		newvp = NFSTOV(np);
1215 		if (attrflag)
1216 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1217 			    0, 1);
1218 		*vpp = newvp;
1219 		cnp->cn_flags |= SAVENAME;
1220 		return (0);
1221 	}
1222 
1223 	if (flags & ISDOTDOT) {
1224 		ltype = NFSVOPISLOCKED(dvp);
1225 		error = vfs_busy(mp, MBF_NOWAIT);
1226 		if (error != 0) {
1227 			vfs_ref(mp);
1228 			NFSVOPUNLOCK(dvp, 0);
1229 			error = vfs_busy(mp, 0);
1230 			NFSVOPLOCK(dvp, ltype | LK_RETRY);
1231 			vfs_rel(mp);
1232 			if (error == 0 && (dvp->v_iflag & VI_DOOMED)) {
1233 				vfs_unbusy(mp);
1234 				error = ENOENT;
1235 			}
1236 			if (error != 0)
1237 				return (error);
1238 		}
1239 		NFSVOPUNLOCK(dvp, 0);
1240 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np, NULL,
1241 		    cnp->cn_lkflags);
1242 		if (error == 0)
1243 			newvp = NFSTOV(np);
1244 		vfs_unbusy(mp);
1245 		if (newvp != dvp)
1246 			NFSVOPLOCK(dvp, ltype | LK_RETRY);
1247 		if (dvp->v_iflag & VI_DOOMED) {
1248 			if (error == 0) {
1249 				if (newvp == dvp)
1250 					vrele(newvp);
1251 				else
1252 					vput(newvp);
1253 			}
1254 			error = ENOENT;
1255 		}
1256 		if (error != 0)
1257 			return (error);
1258 		if (attrflag)
1259 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1260 			    0, 1);
1261 	} else if (NFS_CMPFH(np, nfhp->nfh_fh, nfhp->nfh_len)) {
1262 		FREE((caddr_t)nfhp, M_NFSFH);
1263 		VREF(dvp);
1264 		newvp = dvp;
1265 		if (attrflag)
1266 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1267 			    0, 1);
1268 	} else {
1269 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np, NULL,
1270 		    cnp->cn_lkflags);
1271 		if (error)
1272 			return (error);
1273 		newvp = NFSTOV(np);
1274 		if (attrflag)
1275 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1276 			    0, 1);
1277 		else if ((flags & (ISLASTCN | ISOPEN)) == (ISLASTCN | ISOPEN) &&
1278 		    !(np->n_flag & NMODIFIED)) {
1279 			/*
1280 			 * Flush the attribute cache when opening a
1281 			 * leaf node to ensure that fresh attributes
1282 			 * are fetched in nfs_open() since we did not
1283 			 * fetch attributes from the LOOKUP reply.
1284 			 */
1285 			mtx_lock(&np->n_mtx);
1286 			np->n_attrstamp = 0;
1287 			KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(newvp);
1288 			mtx_unlock(&np->n_mtx);
1289 		}
1290 	}
1291 	if (cnp->cn_nameiop != LOOKUP && (flags & ISLASTCN))
1292 		cnp->cn_flags |= SAVENAME;
1293 	if ((cnp->cn_flags & MAKEENTRY) &&
1294 	    (cnp->cn_nameiop != DELETE || !(flags & ISLASTCN)) &&
1295 	    attrflag != 0 && (newvp->v_type != VDIR || dattrflag != 0))
1296 		cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime,
1297 		    newvp->v_type != VDIR ? NULL : &dnfsva.na_ctime);
1298 	*vpp = newvp;
1299 	return (0);
1300 }
1301 
1302 /*
1303  * nfs read call.
1304  * Just call ncl_bioread() to do the work.
1305  */
1306 static int
1307 nfs_read(struct vop_read_args *ap)
1308 {
1309 	struct vnode *vp = ap->a_vp;
1310 
1311 	switch (vp->v_type) {
1312 	case VREG:
1313 		return (ncl_bioread(vp, ap->a_uio, ap->a_ioflag, ap->a_cred));
1314 	case VDIR:
1315 		return (EISDIR);
1316 	default:
1317 		return (EOPNOTSUPP);
1318 	}
1319 }
1320 
1321 /*
1322  * nfs readlink call
1323  */
1324 static int
1325 nfs_readlink(struct vop_readlink_args *ap)
1326 {
1327 	struct vnode *vp = ap->a_vp;
1328 
1329 	if (vp->v_type != VLNK)
1330 		return (EINVAL);
1331 	return (ncl_bioread(vp, ap->a_uio, 0, ap->a_cred));
1332 }
1333 
1334 /*
1335  * Do a readlink rpc.
1336  * Called by ncl_doio() from below the buffer cache.
1337  */
1338 int
1339 ncl_readlinkrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred)
1340 {
1341 	int error, ret, attrflag;
1342 	struct nfsvattr nfsva;
1343 
1344 	error = nfsrpc_readlink(vp, uiop, cred, uiop->uio_td, &nfsva,
1345 	    &attrflag, NULL);
1346 	if (attrflag) {
1347 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
1348 		if (ret && !error)
1349 			error = ret;
1350 	}
1351 	if (error && NFS_ISV4(vp))
1352 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1353 	return (error);
1354 }
1355 
1356 /*
1357  * nfs read rpc call
1358  * Ditto above
1359  */
1360 int
1361 ncl_readrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred)
1362 {
1363 	int error, ret, attrflag;
1364 	struct nfsvattr nfsva;
1365 
1366 	error = nfsrpc_read(vp, uiop, cred, uiop->uio_td, &nfsva, &attrflag,
1367 	    NULL);
1368 	if (attrflag) {
1369 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
1370 		if (ret && !error)
1371 			error = ret;
1372 	}
1373 	if (error && NFS_ISV4(vp))
1374 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1375 	return (error);
1376 }
1377 
1378 /*
1379  * nfs write call
1380  */
1381 int
1382 ncl_writerpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
1383     int *iomode, int *must_commit, int called_from_strategy)
1384 {
1385 	struct nfsvattr nfsva;
1386 	int error = 0, attrflag, ret;
1387 
1388 	error = nfsrpc_write(vp, uiop, iomode, must_commit, cred,
1389 	    uiop->uio_td, &nfsva, &attrflag, NULL, called_from_strategy);
1390 	if (attrflag) {
1391 		if (VTONFS(vp)->n_flag & ND_NFSV4)
1392 			ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 1,
1393 			    1);
1394 		else
1395 			ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0,
1396 			    1);
1397 		if (ret && !error)
1398 			error = ret;
1399 	}
1400 	if (DOINGASYNC(vp))
1401 		*iomode = NFSWRITE_FILESYNC;
1402 	if (error && NFS_ISV4(vp))
1403 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1404 	return (error);
1405 }
1406 
1407 /*
1408  * nfs mknod rpc
1409  * For NFS v2 this is a kludge. Use a create rpc but with the IFMT bits of the
1410  * mode set to specify the file type and the size field for rdev.
1411  */
1412 static int
1413 nfs_mknodrpc(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp,
1414     struct vattr *vap)
1415 {
1416 	struct nfsvattr nfsva, dnfsva;
1417 	struct vnode *newvp = NULL;
1418 	struct nfsnode *np = NULL, *dnp;
1419 	struct nfsfh *nfhp;
1420 	struct vattr vattr;
1421 	int error = 0, attrflag, dattrflag;
1422 	u_int32_t rdev;
1423 
1424 	if (vap->va_type == VCHR || vap->va_type == VBLK)
1425 		rdev = vap->va_rdev;
1426 	else if (vap->va_type == VFIFO || vap->va_type == VSOCK)
1427 		rdev = 0xffffffff;
1428 	else
1429 		return (EOPNOTSUPP);
1430 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)))
1431 		return (error);
1432 	error = nfsrpc_mknod(dvp, cnp->cn_nameptr, cnp->cn_namelen, vap,
1433 	    rdev, vap->va_type, cnp->cn_cred, cnp->cn_thread, &dnfsva,
1434 	    &nfsva, &nfhp, &attrflag, &dattrflag, NULL);
1435 	if (!error) {
1436 		if (!nfhp)
1437 			(void) nfsrpc_lookup(dvp, cnp->cn_nameptr,
1438 			    cnp->cn_namelen, cnp->cn_cred, cnp->cn_thread,
1439 			    &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag,
1440 			    NULL);
1441 		if (nfhp)
1442 			error = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp,
1443 			    cnp->cn_thread, &np, NULL, LK_EXCLUSIVE);
1444 	}
1445 	if (dattrflag)
1446 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
1447 	if (!error) {
1448 		newvp = NFSTOV(np);
1449 		if (attrflag != 0) {
1450 			error = nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1451 			    0, 1);
1452 			if (error != 0)
1453 				vput(newvp);
1454 		}
1455 	}
1456 	if (!error) {
1457 		*vpp = newvp;
1458 	} else if (NFS_ISV4(dvp)) {
1459 		error = nfscl_maperr(cnp->cn_thread, error, vap->va_uid,
1460 		    vap->va_gid);
1461 	}
1462 	dnp = VTONFS(dvp);
1463 	mtx_lock(&dnp->n_mtx);
1464 	dnp->n_flag |= NMODIFIED;
1465 	if (!dattrflag) {
1466 		dnp->n_attrstamp = 0;
1467 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1468 	}
1469 	mtx_unlock(&dnp->n_mtx);
1470 	return (error);
1471 }
1472 
1473 /*
1474  * nfs mknod vop
1475  * just call nfs_mknodrpc() to do the work.
1476  */
1477 /* ARGSUSED */
1478 static int
1479 nfs_mknod(struct vop_mknod_args *ap)
1480 {
1481 	return (nfs_mknodrpc(ap->a_dvp, ap->a_vpp, ap->a_cnp, ap->a_vap));
1482 }
1483 
1484 static struct mtx nfs_cverf_mtx;
1485 MTX_SYSINIT(nfs_cverf_mtx, &nfs_cverf_mtx, "NFS create verifier mutex",
1486     MTX_DEF);
1487 
1488 static nfsquad_t
1489 nfs_get_cverf(void)
1490 {
1491 	static nfsquad_t cverf;
1492 	nfsquad_t ret;
1493 	static int cverf_initialized = 0;
1494 
1495 	mtx_lock(&nfs_cverf_mtx);
1496 	if (cverf_initialized == 0) {
1497 		cverf.lval[0] = arc4random();
1498 		cverf.lval[1] = arc4random();
1499 		cverf_initialized = 1;
1500 	} else
1501 		cverf.qval++;
1502 	ret = cverf;
1503 	mtx_unlock(&nfs_cverf_mtx);
1504 
1505 	return (ret);
1506 }
1507 
1508 /*
1509  * nfs file create call
1510  */
1511 static int
1512 nfs_create(struct vop_create_args *ap)
1513 {
1514 	struct vnode *dvp = ap->a_dvp;
1515 	struct vattr *vap = ap->a_vap;
1516 	struct componentname *cnp = ap->a_cnp;
1517 	struct nfsnode *np = NULL, *dnp;
1518 	struct vnode *newvp = NULL;
1519 	struct nfsmount *nmp;
1520 	struct nfsvattr dnfsva, nfsva;
1521 	struct nfsfh *nfhp;
1522 	nfsquad_t cverf;
1523 	int error = 0, attrflag, dattrflag, fmode = 0;
1524 	struct vattr vattr;
1525 
1526 	/*
1527 	 * Oops, not for me..
1528 	 */
1529 	if (vap->va_type == VSOCK)
1530 		return (nfs_mknodrpc(dvp, ap->a_vpp, cnp, vap));
1531 
1532 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)))
1533 		return (error);
1534 	if (vap->va_vaflags & VA_EXCLUSIVE)
1535 		fmode |= O_EXCL;
1536 	dnp = VTONFS(dvp);
1537 	nmp = VFSTONFS(vnode_mount(dvp));
1538 again:
1539 	/* For NFSv4, wait until any remove is done. */
1540 	mtx_lock(&dnp->n_mtx);
1541 	while (NFSHASNFSV4(nmp) && (dnp->n_flag & NREMOVEINPROG)) {
1542 		dnp->n_flag |= NREMOVEWANT;
1543 		(void) msleep((caddr_t)dnp, &dnp->n_mtx, PZERO, "nfscrt", 0);
1544 	}
1545 	mtx_unlock(&dnp->n_mtx);
1546 
1547 	cverf = nfs_get_cverf();
1548 	error = nfsrpc_create(dvp, cnp->cn_nameptr, cnp->cn_namelen,
1549 	    vap, cverf, fmode, cnp->cn_cred, cnp->cn_thread, &dnfsva, &nfsva,
1550 	    &nfhp, &attrflag, &dattrflag, NULL);
1551 	if (!error) {
1552 		if (nfhp == NULL)
1553 			(void) nfsrpc_lookup(dvp, cnp->cn_nameptr,
1554 			    cnp->cn_namelen, cnp->cn_cred, cnp->cn_thread,
1555 			    &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag,
1556 			    NULL);
1557 		if (nfhp != NULL)
1558 			error = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp,
1559 			    cnp->cn_thread, &np, NULL, LK_EXCLUSIVE);
1560 	}
1561 	if (dattrflag)
1562 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
1563 	if (!error) {
1564 		newvp = NFSTOV(np);
1565 		if (attrflag == 0)
1566 			error = nfsrpc_getattr(newvp, cnp->cn_cred,
1567 			    cnp->cn_thread, &nfsva, NULL);
1568 		if (error == 0)
1569 			error = nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1570 			    0, 1);
1571 	}
1572 	if (error) {
1573 		if (newvp != NULL) {
1574 			vput(newvp);
1575 			newvp = NULL;
1576 		}
1577 		if (NFS_ISV34(dvp) && (fmode & O_EXCL) &&
1578 		    error == NFSERR_NOTSUPP) {
1579 			fmode &= ~O_EXCL;
1580 			goto again;
1581 		}
1582 	} else if (NFS_ISV34(dvp) && (fmode & O_EXCL)) {
1583 		if (nfscl_checksattr(vap, &nfsva)) {
1584 			/*
1585 			 * We are normally called with only a partially
1586 			 * initialized VAP. Since the NFSv3 spec says that
1587 			 * the server may use the file attributes to
1588 			 * store the verifier, the spec requires us to do a
1589 			 * SETATTR RPC. FreeBSD servers store the verifier in
1590 			 * atime, but we can't really assume that all servers
1591 			 * will so we ensure that our SETATTR sets both atime
1592 			 * and mtime.
1593 			 */
1594 			if (vap->va_mtime.tv_sec == VNOVAL)
1595 				vfs_timestamp(&vap->va_mtime);
1596 			if (vap->va_atime.tv_sec == VNOVAL)
1597 				vap->va_atime = vap->va_mtime;
1598 			error = nfsrpc_setattr(newvp, vap, NULL, cnp->cn_cred,
1599 			    cnp->cn_thread, &nfsva, &attrflag, NULL);
1600 			if (error && (vap->va_uid != (uid_t)VNOVAL ||
1601 			    vap->va_gid != (gid_t)VNOVAL)) {
1602 				/* try again without setting uid/gid */
1603 				vap->va_uid = (uid_t)VNOVAL;
1604 				vap->va_gid = (uid_t)VNOVAL;
1605 				error = nfsrpc_setattr(newvp, vap, NULL,
1606 				    cnp->cn_cred, cnp->cn_thread, &nfsva,
1607 				    &attrflag, NULL);
1608 			}
1609 			if (attrflag)
1610 				(void) nfscl_loadattrcache(&newvp, &nfsva, NULL,
1611 				    NULL, 0, 1);
1612 			if (error != 0)
1613 				vput(newvp);
1614 		}
1615 	}
1616 	if (!error) {
1617 		if ((cnp->cn_flags & MAKEENTRY) && attrflag)
1618 			cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime,
1619 			    NULL);
1620 		*ap->a_vpp = newvp;
1621 	} else if (NFS_ISV4(dvp)) {
1622 		error = nfscl_maperr(cnp->cn_thread, error, vap->va_uid,
1623 		    vap->va_gid);
1624 	}
1625 	mtx_lock(&dnp->n_mtx);
1626 	dnp->n_flag |= NMODIFIED;
1627 	if (!dattrflag) {
1628 		dnp->n_attrstamp = 0;
1629 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1630 	}
1631 	mtx_unlock(&dnp->n_mtx);
1632 	return (error);
1633 }
1634 
1635 /*
1636  * nfs file remove call
1637  * To try and make nfs semantics closer to ufs semantics, a file that has
1638  * other processes using the vnode is renamed instead of removed and then
1639  * removed later on the last close.
1640  * - If v_usecount > 1
1641  *	  If a rename is not already in the works
1642  *	     call nfs_sillyrename() to set it up
1643  *     else
1644  *	  do the remove rpc
1645  */
1646 static int
1647 nfs_remove(struct vop_remove_args *ap)
1648 {
1649 	struct vnode *vp = ap->a_vp;
1650 	struct vnode *dvp = ap->a_dvp;
1651 	struct componentname *cnp = ap->a_cnp;
1652 	struct nfsnode *np = VTONFS(vp);
1653 	int error = 0;
1654 	struct vattr vattr;
1655 
1656 	KASSERT((cnp->cn_flags & HASBUF) != 0, ("nfs_remove: no name"));
1657 	KASSERT(vrefcnt(vp) > 0, ("nfs_remove: bad v_usecount"));
1658 	if (vp->v_type == VDIR)
1659 		error = EPERM;
1660 	else if (vrefcnt(vp) == 1 || (np->n_sillyrename &&
1661 	    VOP_GETATTR(vp, &vattr, cnp->cn_cred) == 0 &&
1662 	    vattr.va_nlink > 1)) {
1663 		/*
1664 		 * Purge the name cache so that the chance of a lookup for
1665 		 * the name succeeding while the remove is in progress is
1666 		 * minimized. Without node locking it can still happen, such
1667 		 * that an I/O op returns ESTALE, but since you get this if
1668 		 * another host removes the file..
1669 		 */
1670 		cache_purge(vp);
1671 		/*
1672 		 * throw away biocache buffers, mainly to avoid
1673 		 * unnecessary delayed writes later.
1674 		 */
1675 		error = ncl_vinvalbuf(vp, 0, cnp->cn_thread, 1);
1676 		/* Do the rpc */
1677 		if (error != EINTR && error != EIO)
1678 			error = nfs_removerpc(dvp, vp, cnp->cn_nameptr,
1679 			    cnp->cn_namelen, cnp->cn_cred, cnp->cn_thread);
1680 		/*
1681 		 * Kludge City: If the first reply to the remove rpc is lost..
1682 		 *   the reply to the retransmitted request will be ENOENT
1683 		 *   since the file was in fact removed
1684 		 *   Therefore, we cheat and return success.
1685 		 */
1686 		if (error == ENOENT)
1687 			error = 0;
1688 	} else if (!np->n_sillyrename)
1689 		error = nfs_sillyrename(dvp, vp, cnp);
1690 	mtx_lock(&np->n_mtx);
1691 	np->n_attrstamp = 0;
1692 	mtx_unlock(&np->n_mtx);
1693 	KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
1694 	return (error);
1695 }
1696 
1697 /*
1698  * nfs file remove rpc called from nfs_inactive
1699  */
1700 int
1701 ncl_removeit(struct sillyrename *sp, struct vnode *vp)
1702 {
1703 	/*
1704 	 * Make sure that the directory vnode is still valid.
1705 	 * XXX we should lock sp->s_dvp here.
1706 	 */
1707 	if (sp->s_dvp->v_type == VBAD)
1708 		return (0);
1709 	return (nfs_removerpc(sp->s_dvp, vp, sp->s_name, sp->s_namlen,
1710 	    sp->s_cred, NULL));
1711 }
1712 
1713 /*
1714  * Nfs remove rpc, called from nfs_remove() and ncl_removeit().
1715  */
1716 static int
1717 nfs_removerpc(struct vnode *dvp, struct vnode *vp, char *name,
1718     int namelen, struct ucred *cred, struct thread *td)
1719 {
1720 	struct nfsvattr dnfsva;
1721 	struct nfsnode *dnp = VTONFS(dvp);
1722 	int error = 0, dattrflag;
1723 
1724 	mtx_lock(&dnp->n_mtx);
1725 	dnp->n_flag |= NREMOVEINPROG;
1726 	mtx_unlock(&dnp->n_mtx);
1727 	error = nfsrpc_remove(dvp, name, namelen, vp, cred, td, &dnfsva,
1728 	    &dattrflag, NULL);
1729 	mtx_lock(&dnp->n_mtx);
1730 	if ((dnp->n_flag & NREMOVEWANT)) {
1731 		dnp->n_flag &= ~(NREMOVEWANT | NREMOVEINPROG);
1732 		mtx_unlock(&dnp->n_mtx);
1733 		wakeup((caddr_t)dnp);
1734 	} else {
1735 		dnp->n_flag &= ~NREMOVEINPROG;
1736 		mtx_unlock(&dnp->n_mtx);
1737 	}
1738 	if (dattrflag)
1739 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
1740 	mtx_lock(&dnp->n_mtx);
1741 	dnp->n_flag |= NMODIFIED;
1742 	if (!dattrflag) {
1743 		dnp->n_attrstamp = 0;
1744 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1745 	}
1746 	mtx_unlock(&dnp->n_mtx);
1747 	if (error && NFS_ISV4(dvp))
1748 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
1749 	return (error);
1750 }
1751 
1752 /*
1753  * nfs file rename call
1754  */
1755 static int
1756 nfs_rename(struct vop_rename_args *ap)
1757 {
1758 	struct vnode *fvp = ap->a_fvp;
1759 	struct vnode *tvp = ap->a_tvp;
1760 	struct vnode *fdvp = ap->a_fdvp;
1761 	struct vnode *tdvp = ap->a_tdvp;
1762 	struct componentname *tcnp = ap->a_tcnp;
1763 	struct componentname *fcnp = ap->a_fcnp;
1764 	struct nfsnode *fnp = VTONFS(ap->a_fvp);
1765 	struct nfsnode *tdnp = VTONFS(ap->a_tdvp);
1766 	struct nfsv4node *newv4 = NULL;
1767 	int error;
1768 
1769 	KASSERT((tcnp->cn_flags & HASBUF) != 0 &&
1770 	    (fcnp->cn_flags & HASBUF) != 0, ("nfs_rename: no name"));
1771 	/* Check for cross-device rename */
1772 	if ((fvp->v_mount != tdvp->v_mount) ||
1773 	    (tvp && (fvp->v_mount != tvp->v_mount))) {
1774 		error = EXDEV;
1775 		goto out;
1776 	}
1777 
1778 	if (fvp == tvp) {
1779 		ncl_printf("nfs_rename: fvp == tvp (can't happen)\n");
1780 		error = 0;
1781 		goto out;
1782 	}
1783 	if ((error = NFSVOPLOCK(fvp, LK_EXCLUSIVE)) != 0)
1784 		goto out;
1785 
1786 	/*
1787 	 * We have to flush B_DELWRI data prior to renaming
1788 	 * the file.  If we don't, the delayed-write buffers
1789 	 * can be flushed out later after the file has gone stale
1790 	 * under NFSV3.  NFSV2 does not have this problem because
1791 	 * ( as far as I can tell ) it flushes dirty buffers more
1792 	 * often.
1793 	 *
1794 	 * Skip the rename operation if the fsync fails, this can happen
1795 	 * due to the server's volume being full, when we pushed out data
1796 	 * that was written back to our cache earlier. Not checking for
1797 	 * this condition can result in potential (silent) data loss.
1798 	 */
1799 	error = VOP_FSYNC(fvp, MNT_WAIT, fcnp->cn_thread);
1800 	NFSVOPUNLOCK(fvp, 0);
1801 	if (!error && tvp)
1802 		error = VOP_FSYNC(tvp, MNT_WAIT, tcnp->cn_thread);
1803 	if (error)
1804 		goto out;
1805 
1806 	/*
1807 	 * If the tvp exists and is in use, sillyrename it before doing the
1808 	 * rename of the new file over it.
1809 	 * XXX Can't sillyrename a directory.
1810 	 */
1811 	if (tvp && vrefcnt(tvp) > 1 && !VTONFS(tvp)->n_sillyrename &&
1812 		tvp->v_type != VDIR && !nfs_sillyrename(tdvp, tvp, tcnp)) {
1813 		vput(tvp);
1814 		tvp = NULL;
1815 	}
1816 
1817 	error = nfs_renamerpc(fdvp, fvp, fcnp->cn_nameptr, fcnp->cn_namelen,
1818 	    tdvp, tvp, tcnp->cn_nameptr, tcnp->cn_namelen, tcnp->cn_cred,
1819 	    tcnp->cn_thread);
1820 
1821 	if (error == 0 && NFS_ISV4(tdvp)) {
1822 		/*
1823 		 * For NFSv4, check to see if it is the same name and
1824 		 * replace the name, if it is different.
1825 		 */
1826 		MALLOC(newv4, struct nfsv4node *,
1827 		    sizeof (struct nfsv4node) +
1828 		    tdnp->n_fhp->nfh_len + tcnp->cn_namelen - 1,
1829 		    M_NFSV4NODE, M_WAITOK);
1830 		mtx_lock(&tdnp->n_mtx);
1831 		mtx_lock(&fnp->n_mtx);
1832 		if (fnp->n_v4 != NULL && fvp->v_type == VREG &&
1833 		    (fnp->n_v4->n4_namelen != tcnp->cn_namelen ||
1834 		      NFSBCMP(tcnp->cn_nameptr, NFS4NODENAME(fnp->n_v4),
1835 		      tcnp->cn_namelen) ||
1836 		      tdnp->n_fhp->nfh_len != fnp->n_v4->n4_fhlen ||
1837 		      NFSBCMP(tdnp->n_fhp->nfh_fh, fnp->n_v4->n4_data,
1838 			tdnp->n_fhp->nfh_len))) {
1839 #ifdef notdef
1840 { char nnn[100]; int nnnl;
1841 nnnl = (tcnp->cn_namelen < 100) ? tcnp->cn_namelen : 99;
1842 bcopy(tcnp->cn_nameptr, nnn, nnnl);
1843 nnn[nnnl] = '\0';
1844 printf("ren replace=%s\n",nnn);
1845 }
1846 #endif
1847 			FREE((caddr_t)fnp->n_v4, M_NFSV4NODE);
1848 			fnp->n_v4 = newv4;
1849 			newv4 = NULL;
1850 			fnp->n_v4->n4_fhlen = tdnp->n_fhp->nfh_len;
1851 			fnp->n_v4->n4_namelen = tcnp->cn_namelen;
1852 			NFSBCOPY(tdnp->n_fhp->nfh_fh, fnp->n_v4->n4_data,
1853 			    tdnp->n_fhp->nfh_len);
1854 			NFSBCOPY(tcnp->cn_nameptr,
1855 			    NFS4NODENAME(fnp->n_v4), tcnp->cn_namelen);
1856 		}
1857 		mtx_unlock(&tdnp->n_mtx);
1858 		mtx_unlock(&fnp->n_mtx);
1859 		if (newv4 != NULL)
1860 			FREE((caddr_t)newv4, M_NFSV4NODE);
1861 	}
1862 
1863 	if (fvp->v_type == VDIR) {
1864 		if (tvp != NULL && tvp->v_type == VDIR)
1865 			cache_purge(tdvp);
1866 		cache_purge(fdvp);
1867 	}
1868 
1869 out:
1870 	if (tdvp == tvp)
1871 		vrele(tdvp);
1872 	else
1873 		vput(tdvp);
1874 	if (tvp)
1875 		vput(tvp);
1876 	vrele(fdvp);
1877 	vrele(fvp);
1878 	/*
1879 	 * Kludge: Map ENOENT => 0 assuming that it is a reply to a retry.
1880 	 */
1881 	if (error == ENOENT)
1882 		error = 0;
1883 	return (error);
1884 }
1885 
1886 /*
1887  * nfs file rename rpc called from nfs_remove() above
1888  */
1889 static int
1890 nfs_renameit(struct vnode *sdvp, struct vnode *svp, struct componentname *scnp,
1891     struct sillyrename *sp)
1892 {
1893 
1894 	return (nfs_renamerpc(sdvp, svp, scnp->cn_nameptr, scnp->cn_namelen,
1895 	    sdvp, NULL, sp->s_name, sp->s_namlen, scnp->cn_cred,
1896 	    scnp->cn_thread));
1897 }
1898 
1899 /*
1900  * Do an nfs rename rpc. Called from nfs_rename() and nfs_renameit().
1901  */
1902 static int
1903 nfs_renamerpc(struct vnode *fdvp, struct vnode *fvp, char *fnameptr,
1904     int fnamelen, struct vnode *tdvp, struct vnode *tvp, char *tnameptr,
1905     int tnamelen, struct ucred *cred, struct thread *td)
1906 {
1907 	struct nfsvattr fnfsva, tnfsva;
1908 	struct nfsnode *fdnp = VTONFS(fdvp);
1909 	struct nfsnode *tdnp = VTONFS(tdvp);
1910 	int error = 0, fattrflag, tattrflag;
1911 
1912 	error = nfsrpc_rename(fdvp, fvp, fnameptr, fnamelen, tdvp, tvp,
1913 	    tnameptr, tnamelen, cred, td, &fnfsva, &tnfsva, &fattrflag,
1914 	    &tattrflag, NULL, NULL);
1915 	mtx_lock(&fdnp->n_mtx);
1916 	fdnp->n_flag |= NMODIFIED;
1917 	if (fattrflag != 0) {
1918 		mtx_unlock(&fdnp->n_mtx);
1919 		(void) nfscl_loadattrcache(&fdvp, &fnfsva, NULL, NULL, 0, 1);
1920 	} else {
1921 		fdnp->n_attrstamp = 0;
1922 		mtx_unlock(&fdnp->n_mtx);
1923 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(fdvp);
1924 	}
1925 	mtx_lock(&tdnp->n_mtx);
1926 	tdnp->n_flag |= NMODIFIED;
1927 	if (tattrflag != 0) {
1928 		mtx_unlock(&tdnp->n_mtx);
1929 		(void) nfscl_loadattrcache(&tdvp, &tnfsva, NULL, NULL, 0, 1);
1930 	} else {
1931 		tdnp->n_attrstamp = 0;
1932 		mtx_unlock(&tdnp->n_mtx);
1933 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(tdvp);
1934 	}
1935 	if (error && NFS_ISV4(fdvp))
1936 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
1937 	return (error);
1938 }
1939 
1940 /*
1941  * nfs hard link create call
1942  */
1943 static int
1944 nfs_link(struct vop_link_args *ap)
1945 {
1946 	struct vnode *vp = ap->a_vp;
1947 	struct vnode *tdvp = ap->a_tdvp;
1948 	struct componentname *cnp = ap->a_cnp;
1949 	struct nfsnode *np, *tdnp;
1950 	struct nfsvattr nfsva, dnfsva;
1951 	int error = 0, attrflag, dattrflag;
1952 
1953 	if (vp->v_mount != tdvp->v_mount) {
1954 		return (EXDEV);
1955 	}
1956 
1957 	/*
1958 	 * Push all writes to the server, so that the attribute cache
1959 	 * doesn't get "out of sync" with the server.
1960 	 * XXX There should be a better way!
1961 	 */
1962 	VOP_FSYNC(vp, MNT_WAIT, cnp->cn_thread);
1963 
1964 	error = nfsrpc_link(tdvp, vp, cnp->cn_nameptr, cnp->cn_namelen,
1965 	    cnp->cn_cred, cnp->cn_thread, &dnfsva, &nfsva, &attrflag,
1966 	    &dattrflag, NULL);
1967 	tdnp = VTONFS(tdvp);
1968 	mtx_lock(&tdnp->n_mtx);
1969 	tdnp->n_flag |= NMODIFIED;
1970 	if (dattrflag != 0) {
1971 		mtx_unlock(&tdnp->n_mtx);
1972 		(void) nfscl_loadattrcache(&tdvp, &dnfsva, NULL, NULL, 0, 1);
1973 	} else {
1974 		tdnp->n_attrstamp = 0;
1975 		mtx_unlock(&tdnp->n_mtx);
1976 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(tdvp);
1977 	}
1978 	if (attrflag)
1979 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
1980 	else {
1981 		np = VTONFS(vp);
1982 		mtx_lock(&np->n_mtx);
1983 		np->n_attrstamp = 0;
1984 		mtx_unlock(&np->n_mtx);
1985 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
1986 	}
1987 	/*
1988 	 * If negative lookup caching is enabled, I might as well
1989 	 * add an entry for this node. Not necessary for correctness,
1990 	 * but if negative caching is enabled, then the system
1991 	 * must care about lookup caching hit rate, so...
1992 	 */
1993 	if (VFSTONFS(vp->v_mount)->nm_negnametimeo != 0 &&
1994 	    (cnp->cn_flags & MAKEENTRY) && attrflag != 0 && error == 0) {
1995 		cache_enter_time(tdvp, vp, cnp, &nfsva.na_ctime, NULL);
1996 	}
1997 	if (error && NFS_ISV4(vp))
1998 		error = nfscl_maperr(cnp->cn_thread, error, (uid_t)0,
1999 		    (gid_t)0);
2000 	return (error);
2001 }
2002 
2003 /*
2004  * nfs symbolic link create call
2005  */
2006 static int
2007 nfs_symlink(struct vop_symlink_args *ap)
2008 {
2009 	struct vnode *dvp = ap->a_dvp;
2010 	struct vattr *vap = ap->a_vap;
2011 	struct componentname *cnp = ap->a_cnp;
2012 	struct nfsvattr nfsva, dnfsva;
2013 	struct nfsfh *nfhp;
2014 	struct nfsnode *np = NULL, *dnp;
2015 	struct vnode *newvp = NULL;
2016 	int error = 0, attrflag, dattrflag, ret;
2017 
2018 	vap->va_type = VLNK;
2019 	error = nfsrpc_symlink(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2020 	    ap->a_target, vap, cnp->cn_cred, cnp->cn_thread, &dnfsva,
2021 	    &nfsva, &nfhp, &attrflag, &dattrflag, NULL);
2022 	if (nfhp) {
2023 		ret = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp, cnp->cn_thread,
2024 		    &np, NULL, LK_EXCLUSIVE);
2025 		if (!ret)
2026 			newvp = NFSTOV(np);
2027 		else if (!error)
2028 			error = ret;
2029 	}
2030 	if (newvp != NULL) {
2031 		if (attrflag)
2032 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
2033 			    0, 1);
2034 	} else if (!error) {
2035 		/*
2036 		 * If we do not have an error and we could not extract the
2037 		 * newvp from the response due to the request being NFSv2, we
2038 		 * have to do a lookup in order to obtain a newvp to return.
2039 		 */
2040 		error = nfs_lookitup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2041 		    cnp->cn_cred, cnp->cn_thread, &np);
2042 		if (!error)
2043 			newvp = NFSTOV(np);
2044 	}
2045 	if (error) {
2046 		if (newvp)
2047 			vput(newvp);
2048 		if (NFS_ISV4(dvp))
2049 			error = nfscl_maperr(cnp->cn_thread, error,
2050 			    vap->va_uid, vap->va_gid);
2051 	} else {
2052 		*ap->a_vpp = newvp;
2053 	}
2054 
2055 	dnp = VTONFS(dvp);
2056 	mtx_lock(&dnp->n_mtx);
2057 	dnp->n_flag |= NMODIFIED;
2058 	if (dattrflag != 0) {
2059 		mtx_unlock(&dnp->n_mtx);
2060 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
2061 	} else {
2062 		dnp->n_attrstamp = 0;
2063 		mtx_unlock(&dnp->n_mtx);
2064 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2065 	}
2066 	/*
2067 	 * If negative lookup caching is enabled, I might as well
2068 	 * add an entry for this node. Not necessary for correctness,
2069 	 * but if negative caching is enabled, then the system
2070 	 * must care about lookup caching hit rate, so...
2071 	 */
2072 	if (VFSTONFS(dvp->v_mount)->nm_negnametimeo != 0 &&
2073 	    (cnp->cn_flags & MAKEENTRY) && attrflag != 0 && error == 0) {
2074 		cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime, NULL);
2075 	}
2076 	return (error);
2077 }
2078 
2079 /*
2080  * nfs make dir call
2081  */
2082 static int
2083 nfs_mkdir(struct vop_mkdir_args *ap)
2084 {
2085 	struct vnode *dvp = ap->a_dvp;
2086 	struct vattr *vap = ap->a_vap;
2087 	struct componentname *cnp = ap->a_cnp;
2088 	struct nfsnode *np = NULL, *dnp;
2089 	struct vnode *newvp = NULL;
2090 	struct vattr vattr;
2091 	struct nfsfh *nfhp;
2092 	struct nfsvattr nfsva, dnfsva;
2093 	int error = 0, attrflag, dattrflag, ret;
2094 
2095 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)) != 0)
2096 		return (error);
2097 	vap->va_type = VDIR;
2098 	error = nfsrpc_mkdir(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2099 	    vap, cnp->cn_cred, cnp->cn_thread, &dnfsva, &nfsva, &nfhp,
2100 	    &attrflag, &dattrflag, NULL);
2101 	dnp = VTONFS(dvp);
2102 	mtx_lock(&dnp->n_mtx);
2103 	dnp->n_flag |= NMODIFIED;
2104 	if (dattrflag != 0) {
2105 		mtx_unlock(&dnp->n_mtx);
2106 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
2107 	} else {
2108 		dnp->n_attrstamp = 0;
2109 		mtx_unlock(&dnp->n_mtx);
2110 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2111 	}
2112 	if (nfhp) {
2113 		ret = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp, cnp->cn_thread,
2114 		    &np, NULL, LK_EXCLUSIVE);
2115 		if (!ret) {
2116 			newvp = NFSTOV(np);
2117 			if (attrflag)
2118 			   (void) nfscl_loadattrcache(&newvp, &nfsva, NULL,
2119 				NULL, 0, 1);
2120 		} else if (!error)
2121 			error = ret;
2122 	}
2123 	if (!error && newvp == NULL) {
2124 		error = nfs_lookitup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2125 		    cnp->cn_cred, cnp->cn_thread, &np);
2126 		if (!error) {
2127 			newvp = NFSTOV(np);
2128 			if (newvp->v_type != VDIR)
2129 				error = EEXIST;
2130 		}
2131 	}
2132 	if (error) {
2133 		if (newvp)
2134 			vput(newvp);
2135 		if (NFS_ISV4(dvp))
2136 			error = nfscl_maperr(cnp->cn_thread, error,
2137 			    vap->va_uid, vap->va_gid);
2138 	} else {
2139 		/*
2140 		 * If negative lookup caching is enabled, I might as well
2141 		 * add an entry for this node. Not necessary for correctness,
2142 		 * but if negative caching is enabled, then the system
2143 		 * must care about lookup caching hit rate, so...
2144 		 */
2145 		if (VFSTONFS(dvp->v_mount)->nm_negnametimeo != 0 &&
2146 		    (cnp->cn_flags & MAKEENTRY) &&
2147 		    attrflag != 0 && dattrflag != 0)
2148 			cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime,
2149 			    &dnfsva.na_ctime);
2150 		*ap->a_vpp = newvp;
2151 	}
2152 	return (error);
2153 }
2154 
2155 /*
2156  * nfs remove directory call
2157  */
2158 static int
2159 nfs_rmdir(struct vop_rmdir_args *ap)
2160 {
2161 	struct vnode *vp = ap->a_vp;
2162 	struct vnode *dvp = ap->a_dvp;
2163 	struct componentname *cnp = ap->a_cnp;
2164 	struct nfsnode *dnp;
2165 	struct nfsvattr dnfsva;
2166 	int error, dattrflag;
2167 
2168 	if (dvp == vp)
2169 		return (EINVAL);
2170 	error = nfsrpc_rmdir(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2171 	    cnp->cn_cred, cnp->cn_thread, &dnfsva, &dattrflag, NULL);
2172 	dnp = VTONFS(dvp);
2173 	mtx_lock(&dnp->n_mtx);
2174 	dnp->n_flag |= NMODIFIED;
2175 	if (dattrflag != 0) {
2176 		mtx_unlock(&dnp->n_mtx);
2177 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
2178 	} else {
2179 		dnp->n_attrstamp = 0;
2180 		mtx_unlock(&dnp->n_mtx);
2181 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2182 	}
2183 
2184 	cache_purge(dvp);
2185 	cache_purge(vp);
2186 	if (error && NFS_ISV4(dvp))
2187 		error = nfscl_maperr(cnp->cn_thread, error, (uid_t)0,
2188 		    (gid_t)0);
2189 	/*
2190 	 * Kludge: Map ENOENT => 0 assuming that you have a reply to a retry.
2191 	 */
2192 	if (error == ENOENT)
2193 		error = 0;
2194 	return (error);
2195 }
2196 
2197 /*
2198  * nfs readdir call
2199  */
2200 static int
2201 nfs_readdir(struct vop_readdir_args *ap)
2202 {
2203 	struct vnode *vp = ap->a_vp;
2204 	struct nfsnode *np = VTONFS(vp);
2205 	struct uio *uio = ap->a_uio;
2206 	ssize_t tresid;
2207 	int error = 0;
2208 	struct vattr vattr;
2209 
2210 	if (vp->v_type != VDIR)
2211 		return(EPERM);
2212 
2213 	/*
2214 	 * First, check for hit on the EOF offset cache
2215 	 */
2216 	if (np->n_direofoffset > 0 && uio->uio_offset >= np->n_direofoffset &&
2217 	    (np->n_flag & NMODIFIED) == 0) {
2218 		if (VOP_GETATTR(vp, &vattr, ap->a_cred) == 0) {
2219 			mtx_lock(&np->n_mtx);
2220 			if ((NFS_ISV4(vp) && np->n_change == vattr.va_filerev) ||
2221 			    !NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime)) {
2222 				mtx_unlock(&np->n_mtx);
2223 				NFSINCRGLOBAL(newnfsstats.direofcache_hits);
2224 				return (0);
2225 			} else
2226 				mtx_unlock(&np->n_mtx);
2227 		}
2228 	}
2229 
2230 	/*
2231 	 * Call ncl_bioread() to do the real work.
2232 	 */
2233 	tresid = uio->uio_resid;
2234 	error = ncl_bioread(vp, uio, 0, ap->a_cred);
2235 
2236 	if (!error && uio->uio_resid == tresid)
2237 		NFSINCRGLOBAL(newnfsstats.direofcache_misses);
2238 	return (error);
2239 }
2240 
2241 /*
2242  * Readdir rpc call.
2243  * Called from below the buffer cache by ncl_doio().
2244  */
2245 int
2246 ncl_readdirrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
2247     struct thread *td)
2248 {
2249 	struct nfsvattr nfsva;
2250 	nfsuint64 *cookiep, cookie;
2251 	struct nfsnode *dnp = VTONFS(vp);
2252 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2253 	int error = 0, eof, attrflag;
2254 
2255 	KASSERT(uiop->uio_iovcnt == 1 &&
2256 	    (uiop->uio_offset & (DIRBLKSIZ - 1)) == 0 &&
2257 	    (uiop->uio_resid & (DIRBLKSIZ - 1)) == 0,
2258 	    ("nfs readdirrpc bad uio"));
2259 
2260 	/*
2261 	 * If there is no cookie, assume directory was stale.
2262 	 */
2263 	ncl_dircookie_lock(dnp);
2264 	cookiep = ncl_getcookie(dnp, uiop->uio_offset, 0);
2265 	if (cookiep) {
2266 		cookie = *cookiep;
2267 		ncl_dircookie_unlock(dnp);
2268 	} else {
2269 		ncl_dircookie_unlock(dnp);
2270 		return (NFSERR_BAD_COOKIE);
2271 	}
2272 
2273 	if (NFSHASNFSV3(nmp) && !NFSHASGOTFSINFO(nmp))
2274 		(void)ncl_fsinfo(nmp, vp, cred, td);
2275 
2276 	error = nfsrpc_readdir(vp, uiop, &cookie, cred, td, &nfsva,
2277 	    &attrflag, &eof, NULL);
2278 	if (attrflag)
2279 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
2280 
2281 	if (!error) {
2282 		/*
2283 		 * We are now either at the end of the directory or have filled
2284 		 * the block.
2285 		 */
2286 		if (eof)
2287 			dnp->n_direofoffset = uiop->uio_offset;
2288 		else {
2289 			if (uiop->uio_resid > 0)
2290 				ncl_printf("EEK! readdirrpc resid > 0\n");
2291 			ncl_dircookie_lock(dnp);
2292 			cookiep = ncl_getcookie(dnp, uiop->uio_offset, 1);
2293 			*cookiep = cookie;
2294 			ncl_dircookie_unlock(dnp);
2295 		}
2296 	} else if (NFS_ISV4(vp)) {
2297 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2298 	}
2299 	return (error);
2300 }
2301 
2302 /*
2303  * NFS V3 readdir plus RPC. Used in place of ncl_readdirrpc().
2304  */
2305 int
2306 ncl_readdirplusrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
2307     struct thread *td)
2308 {
2309 	struct nfsvattr nfsva;
2310 	nfsuint64 *cookiep, cookie;
2311 	struct nfsnode *dnp = VTONFS(vp);
2312 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2313 	int error = 0, attrflag, eof;
2314 
2315 	KASSERT(uiop->uio_iovcnt == 1 &&
2316 	    (uiop->uio_offset & (DIRBLKSIZ - 1)) == 0 &&
2317 	    (uiop->uio_resid & (DIRBLKSIZ - 1)) == 0,
2318 	    ("nfs readdirplusrpc bad uio"));
2319 
2320 	/*
2321 	 * If there is no cookie, assume directory was stale.
2322 	 */
2323 	ncl_dircookie_lock(dnp);
2324 	cookiep = ncl_getcookie(dnp, uiop->uio_offset, 0);
2325 	if (cookiep) {
2326 		cookie = *cookiep;
2327 		ncl_dircookie_unlock(dnp);
2328 	} else {
2329 		ncl_dircookie_unlock(dnp);
2330 		return (NFSERR_BAD_COOKIE);
2331 	}
2332 
2333 	if (NFSHASNFSV3(nmp) && !NFSHASGOTFSINFO(nmp))
2334 		(void)ncl_fsinfo(nmp, vp, cred, td);
2335 	error = nfsrpc_readdirplus(vp, uiop, &cookie, cred, td, &nfsva,
2336 	    &attrflag, &eof, NULL);
2337 	if (attrflag)
2338 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
2339 
2340 	if (!error) {
2341 		/*
2342 		 * We are now either at end of the directory or have filled the
2343 		 * the block.
2344 		 */
2345 		if (eof)
2346 			dnp->n_direofoffset = uiop->uio_offset;
2347 		else {
2348 			if (uiop->uio_resid > 0)
2349 				ncl_printf("EEK! readdirplusrpc resid > 0\n");
2350 			ncl_dircookie_lock(dnp);
2351 			cookiep = ncl_getcookie(dnp, uiop->uio_offset, 1);
2352 			*cookiep = cookie;
2353 			ncl_dircookie_unlock(dnp);
2354 		}
2355 	} else if (NFS_ISV4(vp)) {
2356 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2357 	}
2358 	return (error);
2359 }
2360 
2361 /*
2362  * Silly rename. To make the NFS filesystem that is stateless look a little
2363  * more like the "ufs" a remove of an active vnode is translated to a rename
2364  * to a funny looking filename that is removed by nfs_inactive on the
2365  * nfsnode. There is the potential for another process on a different client
2366  * to create the same funny name between the nfs_lookitup() fails and the
2367  * nfs_rename() completes, but...
2368  */
2369 static int
2370 nfs_sillyrename(struct vnode *dvp, struct vnode *vp, struct componentname *cnp)
2371 {
2372 	struct sillyrename *sp;
2373 	struct nfsnode *np;
2374 	int error;
2375 	short pid;
2376 	unsigned int lticks;
2377 
2378 	cache_purge(dvp);
2379 	np = VTONFS(vp);
2380 	KASSERT(vp->v_type != VDIR, ("nfs: sillyrename dir"));
2381 	MALLOC(sp, struct sillyrename *, sizeof (struct sillyrename),
2382 	    M_NEWNFSREQ, M_WAITOK);
2383 	sp->s_cred = crhold(cnp->cn_cred);
2384 	sp->s_dvp = dvp;
2385 	VREF(dvp);
2386 
2387 	/*
2388 	 * Fudge together a funny name.
2389 	 * Changing the format of the funny name to accomodate more
2390 	 * sillynames per directory.
2391 	 * The name is now changed to .nfs.<ticks>.<pid>.4, where ticks is
2392 	 * CPU ticks since boot.
2393 	 */
2394 	pid = cnp->cn_thread->td_proc->p_pid;
2395 	lticks = (unsigned int)ticks;
2396 	for ( ; ; ) {
2397 		sp->s_namlen = sprintf(sp->s_name,
2398 				       ".nfs.%08x.%04x4.4", lticks,
2399 				       pid);
2400 		if (nfs_lookitup(dvp, sp->s_name, sp->s_namlen, sp->s_cred,
2401 				 cnp->cn_thread, NULL))
2402 			break;
2403 		lticks++;
2404 	}
2405 	error = nfs_renameit(dvp, vp, cnp, sp);
2406 	if (error)
2407 		goto bad;
2408 	error = nfs_lookitup(dvp, sp->s_name, sp->s_namlen, sp->s_cred,
2409 		cnp->cn_thread, &np);
2410 	np->n_sillyrename = sp;
2411 	return (0);
2412 bad:
2413 	vrele(sp->s_dvp);
2414 	crfree(sp->s_cred);
2415 	free((caddr_t)sp, M_NEWNFSREQ);
2416 	return (error);
2417 }
2418 
2419 /*
2420  * Look up a file name and optionally either update the file handle or
2421  * allocate an nfsnode, depending on the value of npp.
2422  * npp == NULL	--> just do the lookup
2423  * *npp == NULL --> allocate a new nfsnode and make sure attributes are
2424  *			handled too
2425  * *npp != NULL --> update the file handle in the vnode
2426  */
2427 static int
2428 nfs_lookitup(struct vnode *dvp, char *name, int len, struct ucred *cred,
2429     struct thread *td, struct nfsnode **npp)
2430 {
2431 	struct vnode *newvp = NULL, *vp;
2432 	struct nfsnode *np, *dnp = VTONFS(dvp);
2433 	struct nfsfh *nfhp, *onfhp;
2434 	struct nfsvattr nfsva, dnfsva;
2435 	struct componentname cn;
2436 	int error = 0, attrflag, dattrflag;
2437 	u_int hash;
2438 
2439 	error = nfsrpc_lookup(dvp, name, len, cred, td, &dnfsva, &nfsva,
2440 	    &nfhp, &attrflag, &dattrflag, NULL);
2441 	if (dattrflag)
2442 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
2443 	if (npp && !error) {
2444 		if (*npp != NULL) {
2445 		    np = *npp;
2446 		    vp = NFSTOV(np);
2447 		    /*
2448 		     * For NFSv4, check to see if it is the same name and
2449 		     * replace the name, if it is different.
2450 		     */
2451 		    if (np->n_v4 != NULL && nfsva.na_type == VREG &&
2452 			(np->n_v4->n4_namelen != len ||
2453 			 NFSBCMP(name, NFS4NODENAME(np->n_v4), len) ||
2454 			 dnp->n_fhp->nfh_len != np->n_v4->n4_fhlen ||
2455 			 NFSBCMP(dnp->n_fhp->nfh_fh, np->n_v4->n4_data,
2456 			 dnp->n_fhp->nfh_len))) {
2457 #ifdef notdef
2458 { char nnn[100]; int nnnl;
2459 nnnl = (len < 100) ? len : 99;
2460 bcopy(name, nnn, nnnl);
2461 nnn[nnnl] = '\0';
2462 printf("replace=%s\n",nnn);
2463 }
2464 #endif
2465 			    FREE((caddr_t)np->n_v4, M_NFSV4NODE);
2466 			    MALLOC(np->n_v4, struct nfsv4node *,
2467 				sizeof (struct nfsv4node) +
2468 				dnp->n_fhp->nfh_len + len - 1,
2469 				M_NFSV4NODE, M_WAITOK);
2470 			    np->n_v4->n4_fhlen = dnp->n_fhp->nfh_len;
2471 			    np->n_v4->n4_namelen = len;
2472 			    NFSBCOPY(dnp->n_fhp->nfh_fh, np->n_v4->n4_data,
2473 				dnp->n_fhp->nfh_len);
2474 			    NFSBCOPY(name, NFS4NODENAME(np->n_v4), len);
2475 		    }
2476 		    hash = fnv_32_buf(nfhp->nfh_fh, nfhp->nfh_len,
2477 			FNV1_32_INIT);
2478 		    onfhp = np->n_fhp;
2479 		    /*
2480 		     * Rehash node for new file handle.
2481 		     */
2482 		    vfs_hash_rehash(vp, hash);
2483 		    np->n_fhp = nfhp;
2484 		    if (onfhp != NULL)
2485 			FREE((caddr_t)onfhp, M_NFSFH);
2486 		    newvp = NFSTOV(np);
2487 		} else if (NFS_CMPFH(dnp, nfhp->nfh_fh, nfhp->nfh_len)) {
2488 		    FREE((caddr_t)nfhp, M_NFSFH);
2489 		    VREF(dvp);
2490 		    newvp = dvp;
2491 		} else {
2492 		    cn.cn_nameptr = name;
2493 		    cn.cn_namelen = len;
2494 		    error = nfscl_nget(dvp->v_mount, dvp, nfhp, &cn, td,
2495 			&np, NULL, LK_EXCLUSIVE);
2496 		    if (error)
2497 			return (error);
2498 		    newvp = NFSTOV(np);
2499 		}
2500 		if (!attrflag && *npp == NULL) {
2501 			if (newvp == dvp)
2502 				vrele(newvp);
2503 			else
2504 				vput(newvp);
2505 			return (ENOENT);
2506 		}
2507 		if (attrflag)
2508 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
2509 			    0, 1);
2510 	}
2511 	if (npp && *npp == NULL) {
2512 		if (error) {
2513 			if (newvp) {
2514 				if (newvp == dvp)
2515 					vrele(newvp);
2516 				else
2517 					vput(newvp);
2518 			}
2519 		} else
2520 			*npp = np;
2521 	}
2522 	if (error && NFS_ISV4(dvp))
2523 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2524 	return (error);
2525 }
2526 
2527 /*
2528  * Nfs Version 3 and 4 commit rpc
2529  */
2530 int
2531 ncl_commit(struct vnode *vp, u_quad_t offset, int cnt, struct ucred *cred,
2532    struct thread *td)
2533 {
2534 	struct nfsvattr nfsva;
2535 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2536 	int error, attrflag;
2537 	u_char verf[NFSX_VERF];
2538 
2539 	mtx_lock(&nmp->nm_mtx);
2540 	if ((nmp->nm_state & NFSSTA_HASWRITEVERF) == 0) {
2541 		mtx_unlock(&nmp->nm_mtx);
2542 		return (0);
2543 	}
2544 	mtx_unlock(&nmp->nm_mtx);
2545 	error = nfsrpc_commit(vp, offset, cnt, cred, td, verf, &nfsva,
2546 	    &attrflag, NULL);
2547 	if (!error) {
2548 		mtx_lock(&nmp->nm_mtx);
2549 		if (NFSBCMP((caddr_t)nmp->nm_verf, verf, NFSX_VERF)) {
2550 			NFSBCOPY(verf, (caddr_t)nmp->nm_verf, NFSX_VERF);
2551 			error = NFSERR_STALEWRITEVERF;
2552 		}
2553 		mtx_unlock(&nmp->nm_mtx);
2554 		if (!error && attrflag)
2555 			(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL,
2556 			    0, 1);
2557 	} else if (NFS_ISV4(vp)) {
2558 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2559 	}
2560 	return (error);
2561 }
2562 
2563 /*
2564  * Strategy routine.
2565  * For async requests when nfsiod(s) are running, queue the request by
2566  * calling ncl_asyncio(), otherwise just all ncl_doio() to do the
2567  * request.
2568  */
2569 static int
2570 nfs_strategy(struct vop_strategy_args *ap)
2571 {
2572 	struct buf *bp = ap->a_bp;
2573 	struct ucred *cr;
2574 
2575 	KASSERT(!(bp->b_flags & B_DONE),
2576 	    ("nfs_strategy: buffer %p unexpectedly marked B_DONE", bp));
2577 	BUF_ASSERT_HELD(bp);
2578 
2579 	if (bp->b_iocmd == BIO_READ)
2580 		cr = bp->b_rcred;
2581 	else
2582 		cr = bp->b_wcred;
2583 
2584 	/*
2585 	 * If the op is asynchronous and an i/o daemon is waiting
2586 	 * queue the request, wake it up and wait for completion
2587 	 * otherwise just do it ourselves.
2588 	 */
2589 	if ((bp->b_flags & B_ASYNC) == 0 ||
2590 	    ncl_asyncio(VFSTONFS(ap->a_vp->v_mount), bp, NOCRED, curthread))
2591 		(void) ncl_doio(ap->a_vp, bp, cr, curthread, 1);
2592 	return (0);
2593 }
2594 
2595 /*
2596  * fsync vnode op. Just call ncl_flush() with commit == 1.
2597  */
2598 /* ARGSUSED */
2599 static int
2600 nfs_fsync(struct vop_fsync_args *ap)
2601 {
2602 
2603 	if (ap->a_vp->v_type != VREG) {
2604 		/*
2605 		 * For NFS, metadata is changed synchronously on the server,
2606 		 * so there is nothing to flush. Also, ncl_flush() clears
2607 		 * the NMODIFIED flag and that shouldn't be done here for
2608 		 * directories.
2609 		 */
2610 		return (0);
2611 	}
2612 	return (ncl_flush(ap->a_vp, ap->a_waitfor, NULL, ap->a_td, 1, 0));
2613 }
2614 
2615 /*
2616  * Flush all the blocks associated with a vnode.
2617  * 	Walk through the buffer pool and push any dirty pages
2618  *	associated with the vnode.
2619  * If the called_from_renewthread argument is TRUE, it has been called
2620  * from the NFSv4 renew thread and, as such, cannot block indefinitely
2621  * waiting for a buffer write to complete.
2622  */
2623 int
2624 ncl_flush(struct vnode *vp, int waitfor, struct ucred *cred, struct thread *td,
2625     int commit, int called_from_renewthread)
2626 {
2627 	struct nfsnode *np = VTONFS(vp);
2628 	struct buf *bp;
2629 	int i;
2630 	struct buf *nbp;
2631 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2632 	int error = 0, slptimeo = 0, slpflag = 0, retv, bvecpos;
2633 	int passone = 1, trycnt = 0;
2634 	u_quad_t off, endoff, toff;
2635 	struct ucred* wcred = NULL;
2636 	struct buf **bvec = NULL;
2637 	struct bufobj *bo;
2638 #ifndef NFS_COMMITBVECSIZ
2639 #define	NFS_COMMITBVECSIZ	20
2640 #endif
2641 	struct buf *bvec_on_stack[NFS_COMMITBVECSIZ];
2642 	int bvecsize = 0, bveccount;
2643 
2644 	if (called_from_renewthread != 0)
2645 		slptimeo = hz;
2646 	if (nmp->nm_flag & NFSMNT_INT)
2647 		slpflag = NFS_PCATCH;
2648 	if (!commit)
2649 		passone = 0;
2650 	bo = &vp->v_bufobj;
2651 	/*
2652 	 * A b_flags == (B_DELWRI | B_NEEDCOMMIT) block has been written to the
2653 	 * server, but has not been committed to stable storage on the server
2654 	 * yet. On the first pass, the byte range is worked out and the commit
2655 	 * rpc is done. On the second pass, ncl_writebp() is called to do the
2656 	 * job.
2657 	 */
2658 again:
2659 	off = (u_quad_t)-1;
2660 	endoff = 0;
2661 	bvecpos = 0;
2662 	if (NFS_ISV34(vp) && commit) {
2663 		if (bvec != NULL && bvec != bvec_on_stack)
2664 			free(bvec, M_TEMP);
2665 		/*
2666 		 * Count up how many buffers waiting for a commit.
2667 		 */
2668 		bveccount = 0;
2669 		BO_LOCK(bo);
2670 		TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2671 			if (!BUF_ISLOCKED(bp) &&
2672 			    (bp->b_flags & (B_DELWRI | B_NEEDCOMMIT))
2673 				== (B_DELWRI | B_NEEDCOMMIT))
2674 				bveccount++;
2675 		}
2676 		/*
2677 		 * Allocate space to remember the list of bufs to commit.  It is
2678 		 * important to use M_NOWAIT here to avoid a race with nfs_write.
2679 		 * If we can't get memory (for whatever reason), we will end up
2680 		 * committing the buffers one-by-one in the loop below.
2681 		 */
2682 		if (bveccount > NFS_COMMITBVECSIZ) {
2683 			/*
2684 			 * Release the vnode interlock to avoid a lock
2685 			 * order reversal.
2686 			 */
2687 			BO_UNLOCK(bo);
2688 			bvec = (struct buf **)
2689 				malloc(bveccount * sizeof(struct buf *),
2690 				       M_TEMP, M_NOWAIT);
2691 			BO_LOCK(bo);
2692 			if (bvec == NULL) {
2693 				bvec = bvec_on_stack;
2694 				bvecsize = NFS_COMMITBVECSIZ;
2695 			} else
2696 				bvecsize = bveccount;
2697 		} else {
2698 			bvec = bvec_on_stack;
2699 			bvecsize = NFS_COMMITBVECSIZ;
2700 		}
2701 		TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2702 			if (bvecpos >= bvecsize)
2703 				break;
2704 			if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
2705 				nbp = TAILQ_NEXT(bp, b_bobufs);
2706 				continue;
2707 			}
2708 			if ((bp->b_flags & (B_DELWRI | B_NEEDCOMMIT)) !=
2709 			    (B_DELWRI | B_NEEDCOMMIT)) {
2710 				BUF_UNLOCK(bp);
2711 				nbp = TAILQ_NEXT(bp, b_bobufs);
2712 				continue;
2713 			}
2714 			BO_UNLOCK(bo);
2715 			bremfree(bp);
2716 			/*
2717 			 * Work out if all buffers are using the same cred
2718 			 * so we can deal with them all with one commit.
2719 			 *
2720 			 * NOTE: we are not clearing B_DONE here, so we have
2721 			 * to do it later on in this routine if we intend to
2722 			 * initiate I/O on the bp.
2723 			 *
2724 			 * Note: to avoid loopback deadlocks, we do not
2725 			 * assign b_runningbufspace.
2726 			 */
2727 			if (wcred == NULL)
2728 				wcred = bp->b_wcred;
2729 			else if (wcred != bp->b_wcred)
2730 				wcred = NOCRED;
2731 			vfs_busy_pages(bp, 1);
2732 
2733 			BO_LOCK(bo);
2734 			/*
2735 			 * bp is protected by being locked, but nbp is not
2736 			 * and vfs_busy_pages() may sleep.  We have to
2737 			 * recalculate nbp.
2738 			 */
2739 			nbp = TAILQ_NEXT(bp, b_bobufs);
2740 
2741 			/*
2742 			 * A list of these buffers is kept so that the
2743 			 * second loop knows which buffers have actually
2744 			 * been committed. This is necessary, since there
2745 			 * may be a race between the commit rpc and new
2746 			 * uncommitted writes on the file.
2747 			 */
2748 			bvec[bvecpos++] = bp;
2749 			toff = ((u_quad_t)bp->b_blkno) * DEV_BSIZE +
2750 				bp->b_dirtyoff;
2751 			if (toff < off)
2752 				off = toff;
2753 			toff += (u_quad_t)(bp->b_dirtyend - bp->b_dirtyoff);
2754 			if (toff > endoff)
2755 				endoff = toff;
2756 		}
2757 		BO_UNLOCK(bo);
2758 	}
2759 	if (bvecpos > 0) {
2760 		/*
2761 		 * Commit data on the server, as required.
2762 		 * If all bufs are using the same wcred, then use that with
2763 		 * one call for all of them, otherwise commit each one
2764 		 * separately.
2765 		 */
2766 		if (wcred != NOCRED)
2767 			retv = ncl_commit(vp, off, (int)(endoff - off),
2768 					  wcred, td);
2769 		else {
2770 			retv = 0;
2771 			for (i = 0; i < bvecpos; i++) {
2772 				off_t off, size;
2773 				bp = bvec[i];
2774 				off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE +
2775 					bp->b_dirtyoff;
2776 				size = (u_quad_t)(bp->b_dirtyend
2777 						  - bp->b_dirtyoff);
2778 				retv = ncl_commit(vp, off, (int)size,
2779 						  bp->b_wcred, td);
2780 				if (retv) break;
2781 			}
2782 		}
2783 
2784 		if (retv == NFSERR_STALEWRITEVERF)
2785 			ncl_clearcommit(vp->v_mount);
2786 
2787 		/*
2788 		 * Now, either mark the blocks I/O done or mark the
2789 		 * blocks dirty, depending on whether the commit
2790 		 * succeeded.
2791 		 */
2792 		for (i = 0; i < bvecpos; i++) {
2793 			bp = bvec[i];
2794 			bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
2795 			if (retv) {
2796 				/*
2797 				 * Error, leave B_DELWRI intact
2798 				 */
2799 				vfs_unbusy_pages(bp);
2800 				brelse(bp);
2801 			} else {
2802 				/*
2803 				 * Success, remove B_DELWRI ( bundirty() ).
2804 				 *
2805 				 * b_dirtyoff/b_dirtyend seem to be NFS
2806 				 * specific.  We should probably move that
2807 				 * into bundirty(). XXX
2808 				 */
2809 				bufobj_wref(bo);
2810 				bp->b_flags |= B_ASYNC;
2811 				bundirty(bp);
2812 				bp->b_flags &= ~B_DONE;
2813 				bp->b_ioflags &= ~BIO_ERROR;
2814 				bp->b_dirtyoff = bp->b_dirtyend = 0;
2815 				bufdone(bp);
2816 			}
2817 		}
2818 	}
2819 
2820 	/*
2821 	 * Start/do any write(s) that are required.
2822 	 */
2823 loop:
2824 	BO_LOCK(bo);
2825 	TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2826 		if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
2827 			if (waitfor != MNT_WAIT || passone)
2828 				continue;
2829 
2830 			error = BUF_TIMELOCK(bp,
2831 			    LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
2832 			    BO_MTX(bo), "nfsfsync", slpflag, slptimeo);
2833 			if (error == 0) {
2834 				BUF_UNLOCK(bp);
2835 				goto loop;
2836 			}
2837 			if (error == ENOLCK) {
2838 				error = 0;
2839 				goto loop;
2840 			}
2841 			if (called_from_renewthread != 0) {
2842 				/*
2843 				 * Return EIO so the flush will be retried
2844 				 * later.
2845 				 */
2846 				error = EIO;
2847 				goto done;
2848 			}
2849 			if (newnfs_sigintr(nmp, td)) {
2850 				error = EINTR;
2851 				goto done;
2852 			}
2853 			if (slpflag & PCATCH) {
2854 				slpflag = 0;
2855 				slptimeo = 2 * hz;
2856 			}
2857 			goto loop;
2858 		}
2859 		if ((bp->b_flags & B_DELWRI) == 0)
2860 			panic("nfs_fsync: not dirty");
2861 		if ((passone || !commit) && (bp->b_flags & B_NEEDCOMMIT)) {
2862 			BUF_UNLOCK(bp);
2863 			continue;
2864 		}
2865 		BO_UNLOCK(bo);
2866 		bremfree(bp);
2867 		if (passone || !commit)
2868 		    bp->b_flags |= B_ASYNC;
2869 		else
2870 		    bp->b_flags |= B_ASYNC;
2871 		bwrite(bp);
2872 		if (newnfs_sigintr(nmp, td)) {
2873 			error = EINTR;
2874 			goto done;
2875 		}
2876 		goto loop;
2877 	}
2878 	if (passone) {
2879 		passone = 0;
2880 		BO_UNLOCK(bo);
2881 		goto again;
2882 	}
2883 	if (waitfor == MNT_WAIT) {
2884 		while (bo->bo_numoutput) {
2885 			error = bufobj_wwait(bo, slpflag, slptimeo);
2886 			if (error) {
2887 			    BO_UNLOCK(bo);
2888 			    if (called_from_renewthread != 0) {
2889 				/*
2890 				 * Return EIO so that the flush will be
2891 				 * retried later.
2892 				 */
2893 				error = EIO;
2894 				goto done;
2895 			    }
2896 			    error = newnfs_sigintr(nmp, td);
2897 			    if (error)
2898 				goto done;
2899 			    if (slpflag & PCATCH) {
2900 				slpflag = 0;
2901 				slptimeo = 2 * hz;
2902 			    }
2903 			    BO_LOCK(bo);
2904 			}
2905 		}
2906 		if (bo->bo_dirty.bv_cnt != 0 && commit) {
2907 			BO_UNLOCK(bo);
2908 			goto loop;
2909 		}
2910 		/*
2911 		 * Wait for all the async IO requests to drain
2912 		 */
2913 		BO_UNLOCK(bo);
2914 		mtx_lock(&np->n_mtx);
2915 		while (np->n_directio_asyncwr > 0) {
2916 			np->n_flag |= NFSYNCWAIT;
2917 			error = newnfs_msleep(td, &np->n_directio_asyncwr,
2918 			    &np->n_mtx, slpflag | (PRIBIO + 1),
2919 			    "nfsfsync", 0);
2920 			if (error) {
2921 				if (newnfs_sigintr(nmp, td)) {
2922 					mtx_unlock(&np->n_mtx);
2923 					error = EINTR;
2924 					goto done;
2925 				}
2926 			}
2927 		}
2928 		mtx_unlock(&np->n_mtx);
2929 	} else
2930 		BO_UNLOCK(bo);
2931 	mtx_lock(&np->n_mtx);
2932 	if (np->n_flag & NWRITEERR) {
2933 		error = np->n_error;
2934 		np->n_flag &= ~NWRITEERR;
2935 	}
2936   	if (commit && bo->bo_dirty.bv_cnt == 0 &&
2937 	    bo->bo_numoutput == 0 && np->n_directio_asyncwr == 0)
2938   		np->n_flag &= ~NMODIFIED;
2939 	mtx_unlock(&np->n_mtx);
2940 done:
2941 	if (bvec != NULL && bvec != bvec_on_stack)
2942 		free(bvec, M_TEMP);
2943 	if (error == 0 && commit != 0 && waitfor == MNT_WAIT &&
2944 	    (bo->bo_dirty.bv_cnt != 0 || bo->bo_numoutput != 0 ||
2945 	     np->n_directio_asyncwr != 0) && trycnt++ < 5) {
2946 		/* try, try again... */
2947 		passone = 1;
2948 		wcred = NULL;
2949 		bvec = NULL;
2950 		bvecsize = 0;
2951 printf("try%d\n", trycnt);
2952 		goto again;
2953 	}
2954 	return (error);
2955 }
2956 
2957 /*
2958  * NFS advisory byte-level locks.
2959  */
2960 static int
2961 nfs_advlock(struct vop_advlock_args *ap)
2962 {
2963 	struct vnode *vp = ap->a_vp;
2964 	struct ucred *cred;
2965 	struct nfsnode *np = VTONFS(ap->a_vp);
2966 	struct proc *p = (struct proc *)ap->a_id;
2967 	struct thread *td = curthread;	/* XXX */
2968 	struct vattr va;
2969 	int ret, error = EOPNOTSUPP;
2970 	u_quad_t size;
2971 
2972 	if (NFS_ISV4(vp) && (ap->a_flags & (F_POSIX | F_FLOCK)) != 0) {
2973 		if (vp->v_type != VREG)
2974 			return (EINVAL);
2975 		if ((ap->a_flags & F_POSIX) != 0)
2976 			cred = p->p_ucred;
2977 		else
2978 			cred = td->td_ucred;
2979 		NFSVOPLOCK(vp, LK_EXCLUSIVE | LK_RETRY);
2980 		if (vp->v_iflag & VI_DOOMED) {
2981 			NFSVOPUNLOCK(vp, 0);
2982 			return (EBADF);
2983 		}
2984 
2985 		/*
2986 		 * If this is unlocking a write locked region, flush and
2987 		 * commit them before unlocking. This is required by
2988 		 * RFC3530 Sec. 9.3.2.
2989 		 */
2990 		if (ap->a_op == F_UNLCK &&
2991 		    nfscl_checkwritelocked(vp, ap->a_fl, cred, td, ap->a_id,
2992 		    ap->a_flags))
2993 			(void) ncl_flush(vp, MNT_WAIT, cred, td, 1, 0);
2994 
2995 		/*
2996 		 * Loop around doing the lock op, while a blocking lock
2997 		 * must wait for the lock op to succeed.
2998 		 */
2999 		do {
3000 			ret = nfsrpc_advlock(vp, np->n_size, ap->a_op,
3001 			    ap->a_fl, 0, cred, td, ap->a_id, ap->a_flags);
3002 			if (ret == NFSERR_DENIED && (ap->a_flags & F_WAIT) &&
3003 			    ap->a_op == F_SETLK) {
3004 				NFSVOPUNLOCK(vp, 0);
3005 				error = nfs_catnap(PZERO | PCATCH, ret,
3006 				    "ncladvl");
3007 				if (error)
3008 					return (EINTR);
3009 				NFSVOPLOCK(vp, LK_EXCLUSIVE | LK_RETRY);
3010 				if (vp->v_iflag & VI_DOOMED) {
3011 					NFSVOPUNLOCK(vp, 0);
3012 					return (EBADF);
3013 				}
3014 			}
3015 		} while (ret == NFSERR_DENIED && (ap->a_flags & F_WAIT) &&
3016 		     ap->a_op == F_SETLK);
3017 		if (ret == NFSERR_DENIED) {
3018 			NFSVOPUNLOCK(vp, 0);
3019 			return (EAGAIN);
3020 		} else if (ret == EINVAL || ret == EBADF || ret == EINTR) {
3021 			NFSVOPUNLOCK(vp, 0);
3022 			return (ret);
3023 		} else if (ret != 0) {
3024 			NFSVOPUNLOCK(vp, 0);
3025 			return (EACCES);
3026 		}
3027 
3028 		/*
3029 		 * Now, if we just got a lock, invalidate data in the buffer
3030 		 * cache, as required, so that the coherency conforms with
3031 		 * RFC3530 Sec. 9.3.2.
3032 		 */
3033 		if (ap->a_op == F_SETLK) {
3034 			if ((np->n_flag & NMODIFIED) == 0) {
3035 				np->n_attrstamp = 0;
3036 				KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
3037 				ret = VOP_GETATTR(vp, &va, cred);
3038 			}
3039 			if ((np->n_flag & NMODIFIED) || ret ||
3040 			    np->n_change != va.va_filerev) {
3041 				(void) ncl_vinvalbuf(vp, V_SAVE, td, 1);
3042 				np->n_attrstamp = 0;
3043 				KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
3044 				ret = VOP_GETATTR(vp, &va, cred);
3045 				if (!ret) {
3046 					np->n_mtime = va.va_mtime;
3047 					np->n_change = va.va_filerev;
3048 				}
3049 			}
3050 		}
3051 		NFSVOPUNLOCK(vp, 0);
3052 		return (0);
3053 	} else if (!NFS_ISV4(vp)) {
3054 		error = NFSVOPLOCK(vp, LK_SHARED);
3055 		if (error)
3056 			return (error);
3057 		if ((VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NOLOCKD) != 0) {
3058 			size = VTONFS(vp)->n_size;
3059 			NFSVOPUNLOCK(vp, 0);
3060 			error = lf_advlock(ap, &(vp->v_lockf), size);
3061 		} else {
3062 			if (nfs_advlock_p != NULL)
3063 				error = nfs_advlock_p(ap);
3064 			else {
3065 				NFSVOPUNLOCK(vp, 0);
3066 				error = ENOLCK;
3067 			}
3068 		}
3069 	}
3070 	return (error);
3071 }
3072 
3073 /*
3074  * NFS advisory byte-level locks.
3075  */
3076 static int
3077 nfs_advlockasync(struct vop_advlockasync_args *ap)
3078 {
3079 	struct vnode *vp = ap->a_vp;
3080 	u_quad_t size;
3081 	int error;
3082 
3083 	if (NFS_ISV4(vp))
3084 		return (EOPNOTSUPP);
3085 	error = NFSVOPLOCK(vp, LK_SHARED);
3086 	if (error)
3087 		return (error);
3088 	if ((VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NOLOCKD) != 0) {
3089 		size = VTONFS(vp)->n_size;
3090 		NFSVOPUNLOCK(vp, 0);
3091 		error = lf_advlockasync(ap, &(vp->v_lockf), size);
3092 	} else {
3093 		NFSVOPUNLOCK(vp, 0);
3094 		error = EOPNOTSUPP;
3095 	}
3096 	return (error);
3097 }
3098 
3099 /*
3100  * Print out the contents of an nfsnode.
3101  */
3102 static int
3103 nfs_print(struct vop_print_args *ap)
3104 {
3105 	struct vnode *vp = ap->a_vp;
3106 	struct nfsnode *np = VTONFS(vp);
3107 
3108 	ncl_printf("\tfileid %ld fsid 0x%x",
3109 	   np->n_vattr.na_fileid, np->n_vattr.na_fsid);
3110 	if (vp->v_type == VFIFO)
3111 		fifo_printinfo(vp);
3112 	printf("\n");
3113 	return (0);
3114 }
3115 
3116 /*
3117  * This is the "real" nfs::bwrite(struct buf*).
3118  * We set B_CACHE if this is a VMIO buffer.
3119  */
3120 int
3121 ncl_writebp(struct buf *bp, int force __unused, struct thread *td)
3122 {
3123 	int s;
3124 	int oldflags = bp->b_flags;
3125 #if 0
3126 	int retv = 1;
3127 	off_t off;
3128 #endif
3129 
3130 	BUF_ASSERT_HELD(bp);
3131 
3132 	if (bp->b_flags & B_INVAL) {
3133 		brelse(bp);
3134 		return(0);
3135 	}
3136 
3137 	bp->b_flags |= B_CACHE;
3138 
3139 	/*
3140 	 * Undirty the bp.  We will redirty it later if the I/O fails.
3141 	 */
3142 
3143 	s = splbio();
3144 	bundirty(bp);
3145 	bp->b_flags &= ~B_DONE;
3146 	bp->b_ioflags &= ~BIO_ERROR;
3147 	bp->b_iocmd = BIO_WRITE;
3148 
3149 	bufobj_wref(bp->b_bufobj);
3150 	curthread->td_ru.ru_oublock++;
3151 	splx(s);
3152 
3153 	/*
3154 	 * Note: to avoid loopback deadlocks, we do not
3155 	 * assign b_runningbufspace.
3156 	 */
3157 	vfs_busy_pages(bp, 1);
3158 
3159 	BUF_KERNPROC(bp);
3160 	bp->b_iooffset = dbtob(bp->b_blkno);
3161 	bstrategy(bp);
3162 
3163 	if( (oldflags & B_ASYNC) == 0) {
3164 		int rtval = bufwait(bp);
3165 
3166 		if (oldflags & B_DELWRI) {
3167 			s = splbio();
3168 			reassignbuf(bp);
3169 			splx(s);
3170 		}
3171 		brelse(bp);
3172 		return (rtval);
3173 	}
3174 
3175 	return (0);
3176 }
3177 
3178 /*
3179  * nfs special file access vnode op.
3180  * Essentially just get vattr and then imitate iaccess() since the device is
3181  * local to the client.
3182  */
3183 static int
3184 nfsspec_access(struct vop_access_args *ap)
3185 {
3186 	struct vattr *vap;
3187 	struct ucred *cred = ap->a_cred;
3188 	struct vnode *vp = ap->a_vp;
3189 	accmode_t accmode = ap->a_accmode;
3190 	struct vattr vattr;
3191 	int error;
3192 
3193 	/*
3194 	 * Disallow write attempts on filesystems mounted read-only;
3195 	 * unless the file is a socket, fifo, or a block or character
3196 	 * device resident on the filesystem.
3197 	 */
3198 	if ((accmode & VWRITE) && (vp->v_mount->mnt_flag & MNT_RDONLY)) {
3199 		switch (vp->v_type) {
3200 		case VREG:
3201 		case VDIR:
3202 		case VLNK:
3203 			return (EROFS);
3204 		default:
3205 			break;
3206 		}
3207 	}
3208 	vap = &vattr;
3209 	error = VOP_GETATTR(vp, vap, cred);
3210 	if (error)
3211 		goto out;
3212 	error  = vaccess(vp->v_type, vap->va_mode, vap->va_uid, vap->va_gid,
3213 	    accmode, cred, NULL);
3214 out:
3215 	return error;
3216 }
3217 
3218 /*
3219  * Read wrapper for fifos.
3220  */
3221 static int
3222 nfsfifo_read(struct vop_read_args *ap)
3223 {
3224 	struct nfsnode *np = VTONFS(ap->a_vp);
3225 	int error;
3226 
3227 	/*
3228 	 * Set access flag.
3229 	 */
3230 	mtx_lock(&np->n_mtx);
3231 	np->n_flag |= NACC;
3232 	getnanotime(&np->n_atim);
3233 	mtx_unlock(&np->n_mtx);
3234 	error = fifo_specops.vop_read(ap);
3235 	return error;
3236 }
3237 
3238 /*
3239  * Write wrapper for fifos.
3240  */
3241 static int
3242 nfsfifo_write(struct vop_write_args *ap)
3243 {
3244 	struct nfsnode *np = VTONFS(ap->a_vp);
3245 
3246 	/*
3247 	 * Set update flag.
3248 	 */
3249 	mtx_lock(&np->n_mtx);
3250 	np->n_flag |= NUPD;
3251 	getnanotime(&np->n_mtim);
3252 	mtx_unlock(&np->n_mtx);
3253 	return(fifo_specops.vop_write(ap));
3254 }
3255 
3256 /*
3257  * Close wrapper for fifos.
3258  *
3259  * Update the times on the nfsnode then do fifo close.
3260  */
3261 static int
3262 nfsfifo_close(struct vop_close_args *ap)
3263 {
3264 	struct vnode *vp = ap->a_vp;
3265 	struct nfsnode *np = VTONFS(vp);
3266 	struct vattr vattr;
3267 	struct timespec ts;
3268 
3269 	mtx_lock(&np->n_mtx);
3270 	if (np->n_flag & (NACC | NUPD)) {
3271 		getnanotime(&ts);
3272 		if (np->n_flag & NACC)
3273 			np->n_atim = ts;
3274 		if (np->n_flag & NUPD)
3275 			np->n_mtim = ts;
3276 		np->n_flag |= NCHG;
3277 		if (vrefcnt(vp) == 1 &&
3278 		    (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
3279 			VATTR_NULL(&vattr);
3280 			if (np->n_flag & NACC)
3281 				vattr.va_atime = np->n_atim;
3282 			if (np->n_flag & NUPD)
3283 				vattr.va_mtime = np->n_mtim;
3284 			mtx_unlock(&np->n_mtx);
3285 			(void)VOP_SETATTR(vp, &vattr, ap->a_cred);
3286 			goto out;
3287 		}
3288 	}
3289 	mtx_unlock(&np->n_mtx);
3290 out:
3291 	return (fifo_specops.vop_close(ap));
3292 }
3293 
3294 /*
3295  * Just call ncl_writebp() with the force argument set to 1.
3296  *
3297  * NOTE: B_DONE may or may not be set in a_bp on call.
3298  */
3299 static int
3300 nfs_bwrite(struct buf *bp)
3301 {
3302 
3303 	return (ncl_writebp(bp, 1, curthread));
3304 }
3305 
3306 struct buf_ops buf_ops_newnfs = {
3307 	.bop_name	=	"buf_ops_nfs",
3308 	.bop_write	=	nfs_bwrite,
3309 	.bop_strategy	=	bufstrategy,
3310 	.bop_sync	=	bufsync,
3311 	.bop_bdflush	=	bufbdflush,
3312 };
3313 
3314 /*
3315  * Cloned from vop_stdlock(), and then the ugly hack added.
3316  */
3317 static int
3318 nfs_lock1(struct vop_lock1_args *ap)
3319 {
3320 	struct vnode *vp = ap->a_vp;
3321 	int error = 0;
3322 
3323 	/*
3324 	 * Since vfs_hash_get() calls vget() and it will no longer work
3325 	 * for FreeBSD8 with flags == 0, I can only think of this horrible
3326 	 * hack to work around it. I call vfs_hash_get() with LK_EXCLOTHER
3327 	 * and then handle it here. All I want for this case is a v_usecount
3328 	 * on the vnode to use for recovery, while another thread might
3329 	 * hold a lock on the vnode. I have the other threads blocked, so
3330 	 * there isn't any race problem.
3331 	 */
3332 	if ((ap->a_flags & LK_TYPE_MASK) == LK_EXCLOTHER) {
3333 		if ((ap->a_flags & LK_INTERLOCK) == 0)
3334 			panic("ncllock1");
3335 		if ((vp->v_iflag & VI_DOOMED))
3336 			error = ENOENT;
3337 		VI_UNLOCK(vp);
3338 		return (error);
3339 	}
3340 	return (_lockmgr_args(vp->v_vnlock, ap->a_flags, VI_MTX(vp),
3341 	    LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, ap->a_file,
3342 	    ap->a_line));
3343 }
3344 
3345 static int
3346 nfs_getacl(struct vop_getacl_args *ap)
3347 {
3348 	int error;
3349 
3350 	if (ap->a_type != ACL_TYPE_NFS4)
3351 		return (EOPNOTSUPP);
3352 	error = nfsrpc_getacl(ap->a_vp, ap->a_cred, ap->a_td, ap->a_aclp,
3353 	    NULL);
3354 	if (error > NFSERR_STALE) {
3355 		(void) nfscl_maperr(ap->a_td, error, (uid_t)0, (gid_t)0);
3356 		error = EPERM;
3357 	}
3358 	return (error);
3359 }
3360 
3361 static int
3362 nfs_setacl(struct vop_setacl_args *ap)
3363 {
3364 	int error;
3365 
3366 	if (ap->a_type != ACL_TYPE_NFS4)
3367 		return (EOPNOTSUPP);
3368 	error = nfsrpc_setacl(ap->a_vp, ap->a_cred, ap->a_td, ap->a_aclp,
3369 	    NULL);
3370 	if (error > NFSERR_STALE) {
3371 		(void) nfscl_maperr(ap->a_td, error, (uid_t)0, (gid_t)0);
3372 		error = EPERM;
3373 	}
3374 	return (error);
3375 }
3376 
3377 /*
3378  * Return POSIX pathconf information applicable to nfs filesystems.
3379  */
3380 static int
3381 nfs_pathconf(struct vop_pathconf_args *ap)
3382 {
3383 	struct nfsv3_pathconf pc;
3384 	struct nfsvattr nfsva;
3385 	struct vnode *vp = ap->a_vp;
3386 	struct thread *td = curthread;
3387 	int attrflag, error;
3388 
3389 	if (NFS_ISV4(vp) || (NFS_ISV3(vp) && (ap->a_name == _PC_LINK_MAX ||
3390 	    ap->a_name == _PC_NAME_MAX || ap->a_name == _PC_CHOWN_RESTRICTED ||
3391 	    ap->a_name == _PC_NO_TRUNC))) {
3392 		/*
3393 		 * Since only the above 4 a_names are returned by the NFSv3
3394 		 * Pathconf RPC, there is no point in doing it for others.
3395 		 */
3396 		error = nfsrpc_pathconf(vp, &pc, td->td_ucred, td, &nfsva,
3397 		    &attrflag, NULL);
3398 		if (attrflag != 0)
3399 			(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0,
3400 			    1);
3401 		if (error != 0)
3402 			return (error);
3403 	} else {
3404 		/*
3405 		 * For NFSv2 (or NFSv3 when not one of the above 4 a_names),
3406 		 * just fake them.
3407 		 */
3408 		pc.pc_linkmax = LINK_MAX;
3409 		pc.pc_namemax = NFS_MAXNAMLEN;
3410 		pc.pc_notrunc = 1;
3411 		pc.pc_chownrestricted = 1;
3412 		pc.pc_caseinsensitive = 0;
3413 		pc.pc_casepreserving = 1;
3414 		error = 0;
3415 	}
3416 	switch (ap->a_name) {
3417 	case _PC_LINK_MAX:
3418 		*ap->a_retval = pc.pc_linkmax;
3419 		break;
3420 	case _PC_NAME_MAX:
3421 		*ap->a_retval = pc.pc_namemax;
3422 		break;
3423 	case _PC_PATH_MAX:
3424 		*ap->a_retval = PATH_MAX;
3425 		break;
3426 	case _PC_PIPE_BUF:
3427 		*ap->a_retval = PIPE_BUF;
3428 		break;
3429 	case _PC_CHOWN_RESTRICTED:
3430 		*ap->a_retval = pc.pc_chownrestricted;
3431 		break;
3432 	case _PC_NO_TRUNC:
3433 		*ap->a_retval = pc.pc_notrunc;
3434 		break;
3435 	case _PC_ACL_EXTENDED:
3436 		*ap->a_retval = 0;
3437 		break;
3438 	case _PC_ACL_NFS4:
3439 		if (NFS_ISV4(vp) && nfsrv_useacl != 0 && attrflag != 0 &&
3440 		    NFSISSET_ATTRBIT(&nfsva.na_suppattr, NFSATTRBIT_ACL))
3441 			*ap->a_retval = 1;
3442 		else
3443 			*ap->a_retval = 0;
3444 		break;
3445 	case _PC_ACL_PATH_MAX:
3446 		if (NFS_ISV4(vp))
3447 			*ap->a_retval = ACL_MAX_ENTRIES;
3448 		else
3449 			*ap->a_retval = 3;
3450 		break;
3451 	case _PC_MAC_PRESENT:
3452 		*ap->a_retval = 0;
3453 		break;
3454 	case _PC_ASYNC_IO:
3455 		/* _PC_ASYNC_IO should have been handled by upper layers. */
3456 		KASSERT(0, ("_PC_ASYNC_IO should not get here"));
3457 		error = EINVAL;
3458 		break;
3459 	case _PC_PRIO_IO:
3460 		*ap->a_retval = 0;
3461 		break;
3462 	case _PC_SYNC_IO:
3463 		*ap->a_retval = 0;
3464 		break;
3465 	case _PC_ALLOC_SIZE_MIN:
3466 		*ap->a_retval = vp->v_mount->mnt_stat.f_bsize;
3467 		break;
3468 	case _PC_FILESIZEBITS:
3469 		if (NFS_ISV34(vp))
3470 			*ap->a_retval = 64;
3471 		else
3472 			*ap->a_retval = 32;
3473 		break;
3474 	case _PC_REC_INCR_XFER_SIZE:
3475 		*ap->a_retval = vp->v_mount->mnt_stat.f_iosize;
3476 		break;
3477 	case _PC_REC_MAX_XFER_SIZE:
3478 		*ap->a_retval = -1; /* means ``unlimited'' */
3479 		break;
3480 	case _PC_REC_MIN_XFER_SIZE:
3481 		*ap->a_retval = vp->v_mount->mnt_stat.f_iosize;
3482 		break;
3483 	case _PC_REC_XFER_ALIGN:
3484 		*ap->a_retval = PAGE_SIZE;
3485 		break;
3486 	case _PC_SYMLINK_MAX:
3487 		*ap->a_retval = NFS_MAXPATHLEN;
3488 		break;
3489 
3490 	default:
3491 		error = EINVAL;
3492 		break;
3493 	}
3494 	return (error);
3495 }
3496 
3497