xref: /freebsd/sys/fs/nfsclient/nfs_clvnops.c (revision 8ef24a0d4b28fe230e20637f56869cc4148cd2ca)
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_inet.h"
43 
44 #include <sys/param.h>
45 #include <sys/kernel.h>
46 #include <sys/systm.h>
47 #include <sys/resourcevar.h>
48 #include <sys/proc.h>
49 #include <sys/mount.h>
50 #include <sys/bio.h>
51 #include <sys/buf.h>
52 #include <sys/jail.h>
53 #include <sys/malloc.h>
54 #include <sys/mbuf.h>
55 #include <sys/namei.h>
56 #include <sys/socket.h>
57 #include <sys/vnode.h>
58 #include <sys/dirent.h>
59 #include <sys/fcntl.h>
60 #include <sys/lockf.h>
61 #include <sys/stat.h>
62 #include <sys/sysctl.h>
63 #include <sys/signalvar.h>
64 
65 #include <vm/vm.h>
66 #include <vm/vm_extern.h>
67 #include <vm/vm_object.h>
68 
69 #include <fs/nfs/nfsport.h>
70 #include <fs/nfsclient/nfsnode.h>
71 #include <fs/nfsclient/nfsmount.h>
72 #include <fs/nfsclient/nfs.h>
73 #include <fs/nfsclient/nfs_kdtrace.h>
74 
75 #include <net/if.h>
76 #include <netinet/in.h>
77 #include <netinet/in_var.h>
78 
79 #include <nfs/nfs_lock.h>
80 
81 #ifdef KDTRACE_HOOKS
82 #include <sys/dtrace_bsd.h>
83 
84 dtrace_nfsclient_accesscache_flush_probe_func_t
85 		dtrace_nfscl_accesscache_flush_done_probe;
86 uint32_t	nfscl_accesscache_flush_done_id;
87 
88 dtrace_nfsclient_accesscache_get_probe_func_t
89 		dtrace_nfscl_accesscache_get_hit_probe,
90 		dtrace_nfscl_accesscache_get_miss_probe;
91 uint32_t	nfscl_accesscache_get_hit_id;
92 uint32_t	nfscl_accesscache_get_miss_id;
93 
94 dtrace_nfsclient_accesscache_load_probe_func_t
95 		dtrace_nfscl_accesscache_load_done_probe;
96 uint32_t	nfscl_accesscache_load_done_id;
97 #endif /* !KDTRACE_HOOKS */
98 
99 /* Defs */
100 #define	TRUE	1
101 #define	FALSE	0
102 
103 extern struct nfsstats newnfsstats;
104 extern int nfsrv_useacl;
105 extern int nfscl_debuglevel;
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	int	nfs_lookitup(struct vnode *, char *, int,
142 		    struct ucred *, struct thread *, struct nfsnode **);
143 static	int	nfs_sillyrename(struct vnode *, struct vnode *,
144 		    struct componentname *);
145 static vop_access_t	nfsspec_access;
146 static vop_readlink_t	nfs_readlink;
147 static vop_print_t	nfs_print;
148 static vop_advlock_t	nfs_advlock;
149 static vop_advlockasync_t nfs_advlockasync;
150 static vop_getacl_t nfs_getacl;
151 static vop_setacl_t nfs_setacl;
152 
153 /*
154  * Global vfs data structures for nfs
155  */
156 struct vop_vector newnfs_vnodeops = {
157 	.vop_default =		&default_vnodeops,
158 	.vop_access =		nfs_access,
159 	.vop_advlock =		nfs_advlock,
160 	.vop_advlockasync =	nfs_advlockasync,
161 	.vop_close =		nfs_close,
162 	.vop_create =		nfs_create,
163 	.vop_fsync =		nfs_fsync,
164 	.vop_getattr =		nfs_getattr,
165 	.vop_getpages =		ncl_getpages,
166 	.vop_putpages =		ncl_putpages,
167 	.vop_inactive =		ncl_inactive,
168 	.vop_link =		nfs_link,
169 	.vop_lookup =		nfs_lookup,
170 	.vop_mkdir =		nfs_mkdir,
171 	.vop_mknod =		nfs_mknod,
172 	.vop_open =		nfs_open,
173 	.vop_pathconf =		nfs_pathconf,
174 	.vop_print =		nfs_print,
175 	.vop_read =		nfs_read,
176 	.vop_readdir =		nfs_readdir,
177 	.vop_readlink =		nfs_readlink,
178 	.vop_reclaim =		ncl_reclaim,
179 	.vop_remove =		nfs_remove,
180 	.vop_rename =		nfs_rename,
181 	.vop_rmdir =		nfs_rmdir,
182 	.vop_setattr =		nfs_setattr,
183 	.vop_strategy =		nfs_strategy,
184 	.vop_symlink =		nfs_symlink,
185 	.vop_write =		ncl_write,
186 	.vop_getacl =		nfs_getacl,
187 	.vop_setacl =		nfs_setacl,
188 };
189 
190 struct vop_vector newnfs_fifoops = {
191 	.vop_default =		&fifo_specops,
192 	.vop_access =		nfsspec_access,
193 	.vop_close =		nfsfifo_close,
194 	.vop_fsync =		nfs_fsync,
195 	.vop_getattr =		nfs_getattr,
196 	.vop_inactive =		ncl_inactive,
197 	.vop_print =		nfs_print,
198 	.vop_read =		nfsfifo_read,
199 	.vop_reclaim =		ncl_reclaim,
200 	.vop_setattr =		nfs_setattr,
201 	.vop_write =		nfsfifo_write,
202 };
203 
204 static int nfs_mknodrpc(struct vnode *dvp, struct vnode **vpp,
205     struct componentname *cnp, struct vattr *vap);
206 static int nfs_removerpc(struct vnode *dvp, struct vnode *vp, char *name,
207     int namelen, struct ucred *cred, struct thread *td);
208 static int nfs_renamerpc(struct vnode *fdvp, struct vnode *fvp,
209     char *fnameptr, int fnamelen, struct vnode *tdvp, struct vnode *tvp,
210     char *tnameptr, int tnamelen, struct ucred *cred, struct thread *td);
211 static int nfs_renameit(struct vnode *sdvp, struct vnode *svp,
212     struct componentname *scnp, struct sillyrename *sp);
213 
214 /*
215  * Global variables
216  */
217 #define	DIRHDSIZ	(sizeof (struct dirent) - (MAXNAMLEN + 1))
218 
219 SYSCTL_DECL(_vfs_nfs);
220 
221 static int	nfsaccess_cache_timeout = NFS_MAXATTRTIMO;
222 SYSCTL_INT(_vfs_nfs, OID_AUTO, access_cache_timeout, CTLFLAG_RW,
223 	   &nfsaccess_cache_timeout, 0, "NFS ACCESS cache timeout");
224 
225 static int	nfs_prime_access_cache = 0;
226 SYSCTL_INT(_vfs_nfs, OID_AUTO, prime_access_cache, CTLFLAG_RW,
227 	   &nfs_prime_access_cache, 0,
228 	   "Prime NFS ACCESS cache when fetching attributes");
229 
230 static int	newnfs_commit_on_close = 0;
231 SYSCTL_INT(_vfs_nfs, OID_AUTO, commit_on_close, CTLFLAG_RW,
232     &newnfs_commit_on_close, 0, "write+commit on close, else only write");
233 
234 static int	nfs_clean_pages_on_close = 1;
235 SYSCTL_INT(_vfs_nfs, OID_AUTO, clean_pages_on_close, CTLFLAG_RW,
236 	   &nfs_clean_pages_on_close, 0, "NFS clean dirty pages on close");
237 
238 int newnfs_directio_enable = 0;
239 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_directio_enable, CTLFLAG_RW,
240 	   &newnfs_directio_enable, 0, "Enable NFS directio");
241 
242 int nfs_keep_dirty_on_error;
243 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_keep_dirty_on_error, CTLFLAG_RW,
244     &nfs_keep_dirty_on_error, 0, "Retry pageout if error returned");
245 
246 /*
247  * This sysctl allows other processes to mmap a file that has been opened
248  * O_DIRECT by a process.  In general, having processes mmap the file while
249  * Direct IO is in progress can lead to Data Inconsistencies.  But, we allow
250  * this by default to prevent DoS attacks - to prevent a malicious user from
251  * opening up files O_DIRECT preventing other users from mmap'ing these
252  * files.  "Protected" environments where stricter consistency guarantees are
253  * required can disable this knob.  The process that opened the file O_DIRECT
254  * cannot mmap() the file, because mmap'ed IO on an O_DIRECT open() is not
255  * meaningful.
256  */
257 int newnfs_directio_allow_mmap = 1;
258 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_directio_allow_mmap, CTLFLAG_RW,
259 	   &newnfs_directio_allow_mmap, 0, "Enable mmaped IO on file with O_DIRECT opens");
260 
261 #if 0
262 SYSCTL_INT(_vfs_nfs, OID_AUTO, access_cache_hits, CTLFLAG_RD,
263 	   &newnfsstats.accesscache_hits, 0, "NFS ACCESS cache hit count");
264 
265 SYSCTL_INT(_vfs_nfs, OID_AUTO, access_cache_misses, CTLFLAG_RD,
266 	   &newnfsstats.accesscache_misses, 0, "NFS ACCESS cache miss count");
267 #endif
268 
269 #define	NFSACCESS_ALL (NFSACCESS_READ | NFSACCESS_MODIFY		\
270 			 | NFSACCESS_EXTEND | NFSACCESS_EXECUTE	\
271 			 | NFSACCESS_DELETE | NFSACCESS_LOOKUP)
272 
273 /*
274  * SMP Locking Note :
275  * The list of locks after the description of the lock is the ordering
276  * of other locks acquired with the lock held.
277  * np->n_mtx : Protects the fields in the nfsnode.
278        VM Object Lock
279        VI_MTX (acquired indirectly)
280  * nmp->nm_mtx : Protects the fields in the nfsmount.
281        rep->r_mtx
282  * ncl_iod_mutex : Global lock, protects shared nfsiod state.
283  * nfs_reqq_mtx : Global lock, protects the nfs_reqq list.
284        nmp->nm_mtx
285        rep->r_mtx
286  * rep->r_mtx : Protects the fields in an nfsreq.
287  */
288 
289 static int
290 nfs34_access_otw(struct vnode *vp, int wmode, struct thread *td,
291     struct ucred *cred, u_int32_t *retmode)
292 {
293 	int error = 0, attrflag, i, lrupos;
294 	u_int32_t rmode;
295 	struct nfsnode *np = VTONFS(vp);
296 	struct nfsvattr nfsva;
297 
298 	error = nfsrpc_accessrpc(vp, wmode, cred, td, &nfsva, &attrflag,
299 	    &rmode, NULL);
300 	if (attrflag)
301 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
302 	if (!error) {
303 		lrupos = 0;
304 		mtx_lock(&np->n_mtx);
305 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++) {
306 			if (np->n_accesscache[i].uid == cred->cr_uid) {
307 				np->n_accesscache[i].mode = rmode;
308 				np->n_accesscache[i].stamp = time_second;
309 				break;
310 			}
311 			if (i > 0 && np->n_accesscache[i].stamp <
312 			    np->n_accesscache[lrupos].stamp)
313 				lrupos = i;
314 		}
315 		if (i == NFS_ACCESSCACHESIZE) {
316 			np->n_accesscache[lrupos].uid = cred->cr_uid;
317 			np->n_accesscache[lrupos].mode = rmode;
318 			np->n_accesscache[lrupos].stamp = time_second;
319 		}
320 		mtx_unlock(&np->n_mtx);
321 		if (retmode != NULL)
322 			*retmode = rmode;
323 		KDTRACE_NFS_ACCESSCACHE_LOAD_DONE(vp, cred->cr_uid, rmode, 0);
324 	} else if (NFS_ISV4(vp)) {
325 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
326 	}
327 #ifdef KDTRACE_HOOKS
328 	if (error != 0)
329 		KDTRACE_NFS_ACCESSCACHE_LOAD_DONE(vp, cred->cr_uid, 0,
330 		    error);
331 #endif
332 	return (error);
333 }
334 
335 /*
336  * nfs access vnode op.
337  * For nfs version 2, just return ok. File accesses may fail later.
338  * For nfs version 3, use the access rpc to check accessibility. If file modes
339  * are changed on the server, accesses might still fail later.
340  */
341 static int
342 nfs_access(struct vop_access_args *ap)
343 {
344 	struct vnode *vp = ap->a_vp;
345 	int error = 0, i, gotahit;
346 	u_int32_t mode, wmode, rmode;
347 	int v34 = NFS_ISV34(vp);
348 	struct nfsnode *np = VTONFS(vp);
349 
350 	/*
351 	 * Disallow write attempts on filesystems mounted read-only;
352 	 * unless the file is a socket, fifo, or a block or character
353 	 * device resident on the filesystem.
354 	 */
355 	if ((ap->a_accmode & (VWRITE | VAPPEND | VWRITE_NAMED_ATTRS |
356 	    VDELETE_CHILD | VWRITE_ATTRIBUTES | VDELETE | VWRITE_ACL |
357 	    VWRITE_OWNER)) != 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) != 0) {
358 		switch (vp->v_type) {
359 		case VREG:
360 		case VDIR:
361 		case VLNK:
362 			return (EROFS);
363 		default:
364 			break;
365 		}
366 	}
367 	/*
368 	 * For nfs v3 or v4, check to see if we have done this recently, and if
369 	 * so return our cached result instead of making an ACCESS call.
370 	 * If not, do an access rpc, otherwise you are stuck emulating
371 	 * ufs_access() locally using the vattr. This may not be correct,
372 	 * since the server may apply other access criteria such as
373 	 * client uid-->server uid mapping that we do not know about.
374 	 */
375 	if (v34) {
376 		if (ap->a_accmode & VREAD)
377 			mode = NFSACCESS_READ;
378 		else
379 			mode = 0;
380 		if (vp->v_type != VDIR) {
381 			if (ap->a_accmode & VWRITE)
382 				mode |= (NFSACCESS_MODIFY | NFSACCESS_EXTEND);
383 			if (ap->a_accmode & VAPPEND)
384 				mode |= NFSACCESS_EXTEND;
385 			if (ap->a_accmode & VEXEC)
386 				mode |= NFSACCESS_EXECUTE;
387 			if (ap->a_accmode & VDELETE)
388 				mode |= NFSACCESS_DELETE;
389 		} else {
390 			if (ap->a_accmode & VWRITE)
391 				mode |= (NFSACCESS_MODIFY | NFSACCESS_EXTEND);
392 			if (ap->a_accmode & VAPPEND)
393 				mode |= NFSACCESS_EXTEND;
394 			if (ap->a_accmode & VEXEC)
395 				mode |= NFSACCESS_LOOKUP;
396 			if (ap->a_accmode & VDELETE)
397 				mode |= NFSACCESS_DELETE;
398 			if (ap->a_accmode & VDELETE_CHILD)
399 				mode |= NFSACCESS_MODIFY;
400 		}
401 		/* XXX safety belt, only make blanket request if caching */
402 		if (nfsaccess_cache_timeout > 0) {
403 			wmode = NFSACCESS_READ | NFSACCESS_MODIFY |
404 				NFSACCESS_EXTEND | NFSACCESS_EXECUTE |
405 				NFSACCESS_DELETE | NFSACCESS_LOOKUP;
406 		} else {
407 			wmode = mode;
408 		}
409 
410 		/*
411 		 * Does our cached result allow us to give a definite yes to
412 		 * this request?
413 		 */
414 		gotahit = 0;
415 		mtx_lock(&np->n_mtx);
416 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++) {
417 			if (ap->a_cred->cr_uid == np->n_accesscache[i].uid) {
418 			    if (time_second < (np->n_accesscache[i].stamp
419 				+ nfsaccess_cache_timeout) &&
420 				(np->n_accesscache[i].mode & mode) == mode) {
421 				NFSINCRGLOBAL(newnfsstats.accesscache_hits);
422 				gotahit = 1;
423 			    }
424 			    break;
425 			}
426 		}
427 		mtx_unlock(&np->n_mtx);
428 #ifdef KDTRACE_HOOKS
429 		if (gotahit != 0)
430 			KDTRACE_NFS_ACCESSCACHE_GET_HIT(vp,
431 			    ap->a_cred->cr_uid, mode);
432 		else
433 			KDTRACE_NFS_ACCESSCACHE_GET_MISS(vp,
434 			    ap->a_cred->cr_uid, mode);
435 #endif
436 		if (gotahit == 0) {
437 			/*
438 			 * Either a no, or a don't know.  Go to the wire.
439 			 */
440 			NFSINCRGLOBAL(newnfsstats.accesscache_misses);
441 		        error = nfs34_access_otw(vp, wmode, ap->a_td,
442 			    ap->a_cred, &rmode);
443 			if (!error &&
444 			    (rmode & mode) != mode)
445 				error = EACCES;
446 		}
447 		return (error);
448 	} else {
449 		if ((error = nfsspec_access(ap)) != 0) {
450 			return (error);
451 		}
452 		/*
453 		 * Attempt to prevent a mapped root from accessing a file
454 		 * which it shouldn't.  We try to read a byte from the file
455 		 * if the user is root and the file is not zero length.
456 		 * After calling nfsspec_access, we should have the correct
457 		 * file size cached.
458 		 */
459 		mtx_lock(&np->n_mtx);
460 		if (ap->a_cred->cr_uid == 0 && (ap->a_accmode & VREAD)
461 		    && VTONFS(vp)->n_size > 0) {
462 			struct iovec aiov;
463 			struct uio auio;
464 			char buf[1];
465 
466 			mtx_unlock(&np->n_mtx);
467 			aiov.iov_base = buf;
468 			aiov.iov_len = 1;
469 			auio.uio_iov = &aiov;
470 			auio.uio_iovcnt = 1;
471 			auio.uio_offset = 0;
472 			auio.uio_resid = 1;
473 			auio.uio_segflg = UIO_SYSSPACE;
474 			auio.uio_rw = UIO_READ;
475 			auio.uio_td = ap->a_td;
476 
477 			if (vp->v_type == VREG)
478 				error = ncl_readrpc(vp, &auio, ap->a_cred);
479 			else if (vp->v_type == VDIR) {
480 				char* bp;
481 				bp = malloc(NFS_DIRBLKSIZ, M_TEMP, M_WAITOK);
482 				aiov.iov_base = bp;
483 				aiov.iov_len = auio.uio_resid = NFS_DIRBLKSIZ;
484 				error = ncl_readdirrpc(vp, &auio, ap->a_cred,
485 				    ap->a_td);
486 				free(bp, M_TEMP);
487 			} else if (vp->v_type == VLNK)
488 				error = ncl_readlinkrpc(vp, &auio, ap->a_cred);
489 			else
490 				error = EACCES;
491 		} else
492 			mtx_unlock(&np->n_mtx);
493 		return (error);
494 	}
495 }
496 
497 
498 /*
499  * nfs open vnode op
500  * Check to see if the type is ok
501  * and that deletion is not in progress.
502  * For paged in text files, you will need to flush the page cache
503  * if consistency is lost.
504  */
505 /* ARGSUSED */
506 static int
507 nfs_open(struct vop_open_args *ap)
508 {
509 	struct vnode *vp = ap->a_vp;
510 	struct nfsnode *np = VTONFS(vp);
511 	struct vattr vattr;
512 	int error;
513 	int fmode = ap->a_mode;
514 	struct ucred *cred;
515 
516 	if (vp->v_type != VREG && vp->v_type != VDIR && vp->v_type != VLNK)
517 		return (EOPNOTSUPP);
518 
519 	/*
520 	 * For NFSv4, we need to do the Open Op before cache validation,
521 	 * so that we conform to RFC3530 Sec. 9.3.1.
522 	 */
523 	if (NFS_ISV4(vp)) {
524 		error = nfsrpc_open(vp, fmode, ap->a_cred, ap->a_td);
525 		if (error) {
526 			error = nfscl_maperr(ap->a_td, error, (uid_t)0,
527 			    (gid_t)0);
528 			return (error);
529 		}
530 	}
531 
532 	/*
533 	 * Now, if this Open will be doing reading, re-validate/flush the
534 	 * cache, so that Close/Open coherency is maintained.
535 	 */
536 	mtx_lock(&np->n_mtx);
537 	if (np->n_flag & NMODIFIED) {
538 		mtx_unlock(&np->n_mtx);
539 		error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
540 		if (error == EINTR || error == EIO) {
541 			if (NFS_ISV4(vp))
542 				(void) nfsrpc_close(vp, 0, ap->a_td);
543 			return (error);
544 		}
545 		mtx_lock(&np->n_mtx);
546 		np->n_attrstamp = 0;
547 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
548 		if (vp->v_type == VDIR)
549 			np->n_direofoffset = 0;
550 		mtx_unlock(&np->n_mtx);
551 		error = VOP_GETATTR(vp, &vattr, ap->a_cred);
552 		if (error) {
553 			if (NFS_ISV4(vp))
554 				(void) nfsrpc_close(vp, 0, ap->a_td);
555 			return (error);
556 		}
557 		mtx_lock(&np->n_mtx);
558 		np->n_mtime = vattr.va_mtime;
559 		if (NFS_ISV4(vp))
560 			np->n_change = vattr.va_filerev;
561 	} else {
562 		mtx_unlock(&np->n_mtx);
563 		error = VOP_GETATTR(vp, &vattr, ap->a_cred);
564 		if (error) {
565 			if (NFS_ISV4(vp))
566 				(void) nfsrpc_close(vp, 0, ap->a_td);
567 			return (error);
568 		}
569 		mtx_lock(&np->n_mtx);
570 		if ((NFS_ISV4(vp) && np->n_change != vattr.va_filerev) ||
571 		    NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime)) {
572 			if (vp->v_type == VDIR)
573 				np->n_direofoffset = 0;
574 			mtx_unlock(&np->n_mtx);
575 			error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
576 			if (error == EINTR || error == EIO) {
577 				if (NFS_ISV4(vp))
578 					(void) nfsrpc_close(vp, 0, ap->a_td);
579 				return (error);
580 			}
581 			mtx_lock(&np->n_mtx);
582 			np->n_mtime = vattr.va_mtime;
583 			if (NFS_ISV4(vp))
584 				np->n_change = vattr.va_filerev;
585 		}
586 	}
587 
588 	/*
589 	 * If the object has >= 1 O_DIRECT active opens, we disable caching.
590 	 */
591 	if (newnfs_directio_enable && (fmode & O_DIRECT) &&
592 	    (vp->v_type == VREG)) {
593 		if (np->n_directio_opens == 0) {
594 			mtx_unlock(&np->n_mtx);
595 			error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
596 			if (error) {
597 				if (NFS_ISV4(vp))
598 					(void) nfsrpc_close(vp, 0, ap->a_td);
599 				return (error);
600 			}
601 			mtx_lock(&np->n_mtx);
602 			np->n_flag |= NNONCACHE;
603 		}
604 		np->n_directio_opens++;
605 	}
606 
607 	/* If opened for writing via NFSv4.1 or later, mark that for pNFS. */
608 	if (NFSHASPNFS(VFSTONFS(vp->v_mount)) && (fmode & FWRITE) != 0)
609 		np->n_flag |= NWRITEOPENED;
610 
611 	/*
612 	 * If this is an open for writing, capture a reference to the
613 	 * credentials, so they can be used by ncl_putpages(). Using
614 	 * these write credentials is preferable to the credentials of
615 	 * whatever thread happens to be doing the VOP_PUTPAGES() since
616 	 * the write RPCs are less likely to fail with EACCES.
617 	 */
618 	if ((fmode & FWRITE) != 0) {
619 		cred = np->n_writecred;
620 		np->n_writecred = crhold(ap->a_cred);
621 	} else
622 		cred = NULL;
623 	mtx_unlock(&np->n_mtx);
624 
625 	if (cred != NULL)
626 		crfree(cred);
627 	vnode_create_vobject(vp, vattr.va_size, ap->a_td);
628 	return (0);
629 }
630 
631 /*
632  * nfs close vnode op
633  * What an NFS client should do upon close after writing is a debatable issue.
634  * Most NFS clients push delayed writes to the server upon close, basically for
635  * two reasons:
636  * 1 - So that any write errors may be reported back to the client process
637  *     doing the close system call. By far the two most likely errors are
638  *     NFSERR_NOSPC and NFSERR_DQUOT to indicate space allocation failure.
639  * 2 - To put a worst case upper bound on cache inconsistency between
640  *     multiple clients for the file.
641  * There is also a consistency problem for Version 2 of the protocol w.r.t.
642  * not being able to tell if other clients are writing a file concurrently,
643  * since there is no way of knowing if the changed modify time in the reply
644  * is only due to the write for this client.
645  * (NFS Version 3 provides weak cache consistency data in the reply that
646  *  should be sufficient to detect and handle this case.)
647  *
648  * The current code does the following:
649  * for NFS Version 2 - play it safe and flush/invalidate all dirty buffers
650  * for NFS Version 3 - flush dirty buffers to the server but don't invalidate
651  *                     or commit them (this satisfies 1 and 2 except for the
652  *                     case where the server crashes after this close but
653  *                     before the commit RPC, which is felt to be "good
654  *                     enough". Changing the last argument to ncl_flush() to
655  *                     a 1 would force a commit operation, if it is felt a
656  *                     commit is necessary now.
657  * for NFS Version 4 - flush the dirty buffers and commit them, if
658  *		       nfscl_mustflush() says this is necessary.
659  *                     It is necessary if there is no write delegation held,
660  *                     in order to satisfy open/close coherency.
661  *                     If the file isn't cached on local stable storage,
662  *                     it may be necessary in order to detect "out of space"
663  *                     errors from the server, if the write delegation
664  *                     issued by the server doesn't allow the file to grow.
665  */
666 /* ARGSUSED */
667 static int
668 nfs_close(struct vop_close_args *ap)
669 {
670 	struct vnode *vp = ap->a_vp;
671 	struct nfsnode *np = VTONFS(vp);
672 	struct nfsvattr nfsva;
673 	struct ucred *cred;
674 	int error = 0, ret, localcred = 0;
675 	int fmode = ap->a_fflag;
676 
677 	if ((vp->v_mount->mnt_kern_flag & MNTK_UNMOUNTF))
678 		return (0);
679 	/*
680 	 * During shutdown, a_cred isn't valid, so just use root.
681 	 */
682 	if (ap->a_cred == NOCRED) {
683 		cred = newnfs_getcred();
684 		localcred = 1;
685 	} else {
686 		cred = ap->a_cred;
687 	}
688 	if (vp->v_type == VREG) {
689 	    /*
690 	     * Examine and clean dirty pages, regardless of NMODIFIED.
691 	     * This closes a major hole in close-to-open consistency.
692 	     * We want to push out all dirty pages (and buffers) on
693 	     * close, regardless of whether they were dirtied by
694 	     * mmap'ed writes or via write().
695 	     */
696 	    if (nfs_clean_pages_on_close && vp->v_object) {
697 		VM_OBJECT_WLOCK(vp->v_object);
698 		vm_object_page_clean(vp->v_object, 0, 0, 0);
699 		VM_OBJECT_WUNLOCK(vp->v_object);
700 	    }
701 	    mtx_lock(&np->n_mtx);
702 	    if (np->n_flag & NMODIFIED) {
703 		mtx_unlock(&np->n_mtx);
704 		if (NFS_ISV3(vp)) {
705 		    /*
706 		     * Under NFSv3 we have dirty buffers to dispose of.  We
707 		     * must flush them to the NFS server.  We have the option
708 		     * of waiting all the way through the commit rpc or just
709 		     * waiting for the initial write.  The default is to only
710 		     * wait through the initial write so the data is in the
711 		     * server's cache, which is roughly similar to the state
712 		     * a standard disk subsystem leaves the file in on close().
713 		     *
714 		     * We cannot clear the NMODIFIED bit in np->n_flag due to
715 		     * potential races with other processes, and certainly
716 		     * cannot clear it if we don't commit.
717 		     * These races occur when there is no longer the old
718 		     * traditional vnode locking implemented for Vnode Ops.
719 		     */
720 		    int cm = newnfs_commit_on_close ? 1 : 0;
721 		    error = ncl_flush(vp, MNT_WAIT, cred, ap->a_td, cm, 0);
722 		    /* np->n_flag &= ~NMODIFIED; */
723 		} else if (NFS_ISV4(vp)) {
724 			if (nfscl_mustflush(vp) != 0) {
725 				int cm = newnfs_commit_on_close ? 1 : 0;
726 				error = ncl_flush(vp, MNT_WAIT, cred, ap->a_td,
727 				    cm, 0);
728 				/*
729 				 * as above w.r.t races when clearing
730 				 * NMODIFIED.
731 				 * np->n_flag &= ~NMODIFIED;
732 				 */
733 			}
734 		} else
735 		    error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
736 		mtx_lock(&np->n_mtx);
737 	    }
738  	    /*
739  	     * Invalidate the attribute cache in all cases.
740  	     * An open is going to fetch fresh attrs any way, other procs
741  	     * on this node that have file open will be forced to do an
742  	     * otw attr fetch, but this is safe.
743 	     * --> A user found that their RPC count dropped by 20% when
744 	     *     this was commented out and I can't see any requirement
745 	     *     for it, so I've disabled it when negative lookups are
746 	     *     enabled. (What does this have to do with negative lookup
747 	     *     caching? Well nothing, except it was reported by the
748 	     *     same user that needed negative lookup caching and I wanted
749 	     *     there to be a way to disable it to see if it
750 	     *     is the cause of some caching/coherency issue that might
751 	     *     crop up.)
752  	     */
753 	    if (VFSTONFS(vp->v_mount)->nm_negnametimeo == 0) {
754 		    np->n_attrstamp = 0;
755 		    KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
756 	    }
757 	    if (np->n_flag & NWRITEERR) {
758 		np->n_flag &= ~NWRITEERR;
759 		error = np->n_error;
760 	    }
761 	    mtx_unlock(&np->n_mtx);
762 	}
763 
764 	if (NFS_ISV4(vp)) {
765 		/*
766 		 * Get attributes so "change" is up to date.
767 		 */
768 		if (error == 0 && nfscl_mustflush(vp) != 0 &&
769 		    vp->v_type == VREG &&
770 		    (VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NOCTO) == 0) {
771 			ret = nfsrpc_getattr(vp, cred, ap->a_td, &nfsva,
772 			    NULL);
773 			if (!ret) {
774 				np->n_change = nfsva.na_filerev;
775 				(void) nfscl_loadattrcache(&vp, &nfsva, NULL,
776 				    NULL, 0, 0);
777 			}
778 		}
779 
780 		/*
781 		 * and do the close.
782 		 */
783 		ret = nfsrpc_close(vp, 0, ap->a_td);
784 		if (!error && ret)
785 			error = ret;
786 		if (error)
787 			error = nfscl_maperr(ap->a_td, error, (uid_t)0,
788 			    (gid_t)0);
789 	}
790 	if (newnfs_directio_enable)
791 		KASSERT((np->n_directio_asyncwr == 0),
792 			("nfs_close: dirty unflushed (%d) directio buffers\n",
793 			 np->n_directio_asyncwr));
794 	if (newnfs_directio_enable && (fmode & O_DIRECT) && (vp->v_type == VREG)) {
795 		mtx_lock(&np->n_mtx);
796 		KASSERT((np->n_directio_opens > 0),
797 			("nfs_close: unexpectedly value (0) of n_directio_opens\n"));
798 		np->n_directio_opens--;
799 		if (np->n_directio_opens == 0)
800 			np->n_flag &= ~NNONCACHE;
801 		mtx_unlock(&np->n_mtx);
802 	}
803 	if (localcred)
804 		NFSFREECRED(cred);
805 	return (error);
806 }
807 
808 /*
809  * nfs getattr call from vfs.
810  */
811 static int
812 nfs_getattr(struct vop_getattr_args *ap)
813 {
814 	struct vnode *vp = ap->a_vp;
815 	struct thread *td = curthread;	/* XXX */
816 	struct nfsnode *np = VTONFS(vp);
817 	int error = 0;
818 	struct nfsvattr nfsva;
819 	struct vattr *vap = ap->a_vap;
820 	struct vattr vattr;
821 
822 	/*
823 	 * Update local times for special files.
824 	 */
825 	mtx_lock(&np->n_mtx);
826 	if (np->n_flag & (NACC | NUPD))
827 		np->n_flag |= NCHG;
828 	mtx_unlock(&np->n_mtx);
829 	/*
830 	 * First look in the cache.
831 	 */
832 	if (ncl_getattrcache(vp, &vattr) == 0) {
833 		vap->va_type = vattr.va_type;
834 		vap->va_mode = vattr.va_mode;
835 		vap->va_nlink = vattr.va_nlink;
836 		vap->va_uid = vattr.va_uid;
837 		vap->va_gid = vattr.va_gid;
838 		vap->va_fsid = vattr.va_fsid;
839 		vap->va_fileid = vattr.va_fileid;
840 		vap->va_size = vattr.va_size;
841 		vap->va_blocksize = vattr.va_blocksize;
842 		vap->va_atime = vattr.va_atime;
843 		vap->va_mtime = vattr.va_mtime;
844 		vap->va_ctime = vattr.va_ctime;
845 		vap->va_gen = vattr.va_gen;
846 		vap->va_flags = vattr.va_flags;
847 		vap->va_rdev = vattr.va_rdev;
848 		vap->va_bytes = vattr.va_bytes;
849 		vap->va_filerev = vattr.va_filerev;
850 		/*
851 		 * Get the local modify time for the case of a write
852 		 * delegation.
853 		 */
854 		nfscl_deleggetmodtime(vp, &vap->va_mtime);
855 		return (0);
856 	}
857 
858 	if (NFS_ISV34(vp) && nfs_prime_access_cache &&
859 	    nfsaccess_cache_timeout > 0) {
860 		NFSINCRGLOBAL(newnfsstats.accesscache_misses);
861 		nfs34_access_otw(vp, NFSACCESS_ALL, td, ap->a_cred, NULL);
862 		if (ncl_getattrcache(vp, ap->a_vap) == 0) {
863 			nfscl_deleggetmodtime(vp, &ap->a_vap->va_mtime);
864 			return (0);
865 		}
866 	}
867 	error = nfsrpc_getattr(vp, ap->a_cred, td, &nfsva, NULL);
868 	if (!error)
869 		error = nfscl_loadattrcache(&vp, &nfsva, vap, NULL, 0, 0);
870 	if (!error) {
871 		/*
872 		 * Get the local modify time for the case of a write
873 		 * delegation.
874 		 */
875 		nfscl_deleggetmodtime(vp, &vap->va_mtime);
876 	} else if (NFS_ISV4(vp)) {
877 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
878 	}
879 	return (error);
880 }
881 
882 /*
883  * nfs setattr call.
884  */
885 static int
886 nfs_setattr(struct vop_setattr_args *ap)
887 {
888 	struct vnode *vp = ap->a_vp;
889 	struct nfsnode *np = VTONFS(vp);
890 	struct thread *td = curthread;	/* XXX */
891 	struct vattr *vap = ap->a_vap;
892 	int error = 0;
893 	u_quad_t tsize;
894 
895 #ifndef nolint
896 	tsize = (u_quad_t)0;
897 #endif
898 
899 	/*
900 	 * Setting of flags and marking of atimes are not supported.
901 	 */
902 	if (vap->va_flags != VNOVAL)
903 		return (EOPNOTSUPP);
904 
905 	/*
906 	 * Disallow write attempts if the filesystem is mounted read-only.
907 	 */
908   	if ((vap->va_flags != VNOVAL || vap->va_uid != (uid_t)VNOVAL ||
909 	    vap->va_gid != (gid_t)VNOVAL || vap->va_atime.tv_sec != VNOVAL ||
910 	    vap->va_mtime.tv_sec != VNOVAL || vap->va_mode != (mode_t)VNOVAL) &&
911 	    (vp->v_mount->mnt_flag & MNT_RDONLY))
912 		return (EROFS);
913 	if (vap->va_size != VNOVAL) {
914  		switch (vp->v_type) {
915  		case VDIR:
916  			return (EISDIR);
917  		case VCHR:
918  		case VBLK:
919  		case VSOCK:
920  		case VFIFO:
921 			if (vap->va_mtime.tv_sec == VNOVAL &&
922 			    vap->va_atime.tv_sec == VNOVAL &&
923 			    vap->va_mode == (mode_t)VNOVAL &&
924 			    vap->va_uid == (uid_t)VNOVAL &&
925 			    vap->va_gid == (gid_t)VNOVAL)
926 				return (0);
927  			vap->va_size = VNOVAL;
928  			break;
929  		default:
930 			/*
931 			 * Disallow write attempts if the filesystem is
932 			 * mounted read-only.
933 			 */
934 			if (vp->v_mount->mnt_flag & MNT_RDONLY)
935 				return (EROFS);
936 			/*
937 			 *  We run vnode_pager_setsize() early (why?),
938 			 * we must set np->n_size now to avoid vinvalbuf
939 			 * V_SAVE races that might setsize a lower
940 			 * value.
941 			 */
942 			mtx_lock(&np->n_mtx);
943 			tsize = np->n_size;
944 			mtx_unlock(&np->n_mtx);
945 			error = ncl_meta_setsize(vp, ap->a_cred, td,
946 			    vap->va_size);
947 			mtx_lock(&np->n_mtx);
948  			if (np->n_flag & NMODIFIED) {
949 			    tsize = np->n_size;
950 			    mtx_unlock(&np->n_mtx);
951  			    if (vap->va_size == 0)
952  				error = ncl_vinvalbuf(vp, 0, td, 1);
953  			    else
954  				error = ncl_vinvalbuf(vp, V_SAVE, td, 1);
955  			    if (error) {
956 				vnode_pager_setsize(vp, tsize);
957 				return (error);
958 			    }
959 			    /*
960 			     * Call nfscl_delegmodtime() to set the modify time
961 			     * locally, as required.
962 			     */
963 			    nfscl_delegmodtime(vp);
964  			} else
965 			    mtx_unlock(&np->n_mtx);
966 			/*
967 			 * np->n_size has already been set to vap->va_size
968 			 * in ncl_meta_setsize(). We must set it again since
969 			 * nfs_loadattrcache() could be called through
970 			 * ncl_meta_setsize() and could modify np->n_size.
971 			 */
972 			mtx_lock(&np->n_mtx);
973  			np->n_vattr.na_size = np->n_size = vap->va_size;
974 			mtx_unlock(&np->n_mtx);
975   		}
976   	} else {
977 		mtx_lock(&np->n_mtx);
978 		if ((vap->va_mtime.tv_sec != VNOVAL || vap->va_atime.tv_sec != VNOVAL) &&
979 		    (np->n_flag & NMODIFIED) && vp->v_type == VREG) {
980 			mtx_unlock(&np->n_mtx);
981 			if ((error = ncl_vinvalbuf(vp, V_SAVE, td, 1)) != 0 &&
982 			    (error == EINTR || error == EIO))
983 				return (error);
984 		} else
985 			mtx_unlock(&np->n_mtx);
986 	}
987 	error = nfs_setattrrpc(vp, vap, ap->a_cred, td);
988 	if (error && vap->va_size != VNOVAL) {
989 		mtx_lock(&np->n_mtx);
990 		np->n_size = np->n_vattr.na_size = tsize;
991 		vnode_pager_setsize(vp, tsize);
992 		mtx_unlock(&np->n_mtx);
993 	}
994 	return (error);
995 }
996 
997 /*
998  * Do an nfs setattr rpc.
999  */
1000 static int
1001 nfs_setattrrpc(struct vnode *vp, struct vattr *vap, struct ucred *cred,
1002     struct thread *td)
1003 {
1004 	struct nfsnode *np = VTONFS(vp);
1005 	int error, ret, attrflag, i;
1006 	struct nfsvattr nfsva;
1007 
1008 	if (NFS_ISV34(vp)) {
1009 		mtx_lock(&np->n_mtx);
1010 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++)
1011 			np->n_accesscache[i].stamp = 0;
1012 		np->n_flag |= NDELEGMOD;
1013 		mtx_unlock(&np->n_mtx);
1014 		KDTRACE_NFS_ACCESSCACHE_FLUSH_DONE(vp);
1015 	}
1016 	error = nfsrpc_setattr(vp, vap, NULL, cred, td, &nfsva, &attrflag,
1017 	    NULL);
1018 	if (attrflag) {
1019 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
1020 		if (ret && !error)
1021 			error = ret;
1022 	}
1023 	if (error && NFS_ISV4(vp))
1024 		error = nfscl_maperr(td, error, vap->va_uid, vap->va_gid);
1025 	return (error);
1026 }
1027 
1028 /*
1029  * nfs lookup call, one step at a time...
1030  * First look in cache
1031  * If not found, unlock the directory nfsnode and do the rpc
1032  */
1033 static int
1034 nfs_lookup(struct vop_lookup_args *ap)
1035 {
1036 	struct componentname *cnp = ap->a_cnp;
1037 	struct vnode *dvp = ap->a_dvp;
1038 	struct vnode **vpp = ap->a_vpp;
1039 	struct mount *mp = dvp->v_mount;
1040 	int flags = cnp->cn_flags;
1041 	struct vnode *newvp;
1042 	struct nfsmount *nmp;
1043 	struct nfsnode *np, *newnp;
1044 	int error = 0, attrflag, dattrflag, ltype, ncticks;
1045 	struct thread *td = cnp->cn_thread;
1046 	struct nfsfh *nfhp;
1047 	struct nfsvattr dnfsva, nfsva;
1048 	struct vattr vattr;
1049 	struct timespec nctime;
1050 
1051 	*vpp = NULLVP;
1052 	if ((flags & ISLASTCN) && (mp->mnt_flag & MNT_RDONLY) &&
1053 	    (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
1054 		return (EROFS);
1055 	if (dvp->v_type != VDIR)
1056 		return (ENOTDIR);
1057 	nmp = VFSTONFS(mp);
1058 	np = VTONFS(dvp);
1059 
1060 	/* For NFSv4, wait until any remove is done. */
1061 	mtx_lock(&np->n_mtx);
1062 	while (NFSHASNFSV4(nmp) && (np->n_flag & NREMOVEINPROG)) {
1063 		np->n_flag |= NREMOVEWANT;
1064 		(void) msleep((caddr_t)np, &np->n_mtx, PZERO, "nfslkup", 0);
1065 	}
1066 	mtx_unlock(&np->n_mtx);
1067 
1068 	if ((error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, td)) != 0)
1069 		return (error);
1070 	error = cache_lookup(dvp, vpp, cnp, &nctime, &ncticks);
1071 	if (error > 0 && error != ENOENT)
1072 		return (error);
1073 	if (error == -1) {
1074 		/*
1075 		 * Lookups of "." are special and always return the
1076 		 * current directory.  cache_lookup() already handles
1077 		 * associated locking bookkeeping, etc.
1078 		 */
1079 		if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
1080 			/* XXX: Is this really correct? */
1081 			if (cnp->cn_nameiop != LOOKUP &&
1082 			    (flags & ISLASTCN))
1083 				cnp->cn_flags |= SAVENAME;
1084 			return (0);
1085 		}
1086 
1087 		/*
1088 		 * We only accept a positive hit in the cache if the
1089 		 * change time of the file matches our cached copy.
1090 		 * Otherwise, we discard the cache entry and fallback
1091 		 * to doing a lookup RPC.  We also only trust cache
1092 		 * entries for less than nm_nametimeo seconds.
1093 		 *
1094 		 * To better handle stale file handles and attributes,
1095 		 * clear the attribute cache of this node if it is a
1096 		 * leaf component, part of an open() call, and not
1097 		 * locally modified before fetching the attributes.
1098 		 * This should allow stale file handles to be detected
1099 		 * here where we can fall back to a LOOKUP RPC to
1100 		 * recover rather than having nfs_open() detect the
1101 		 * stale file handle and failing open(2) with ESTALE.
1102 		 */
1103 		newvp = *vpp;
1104 		newnp = VTONFS(newvp);
1105 		if (!(nmp->nm_flag & NFSMNT_NOCTO) &&
1106 		    (flags & (ISLASTCN | ISOPEN)) == (ISLASTCN | ISOPEN) &&
1107 		    !(newnp->n_flag & NMODIFIED)) {
1108 			mtx_lock(&newnp->n_mtx);
1109 			newnp->n_attrstamp = 0;
1110 			KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(newvp);
1111 			mtx_unlock(&newnp->n_mtx);
1112 		}
1113 		if (nfscl_nodeleg(newvp, 0) == 0 ||
1114 		    ((u_int)(ticks - ncticks) < (nmp->nm_nametimeo * hz) &&
1115 		    VOP_GETATTR(newvp, &vattr, cnp->cn_cred) == 0 &&
1116 		    timespeccmp(&vattr.va_ctime, &nctime, ==))) {
1117 			NFSINCRGLOBAL(newnfsstats.lookupcache_hits);
1118 			if (cnp->cn_nameiop != LOOKUP &&
1119 			    (flags & ISLASTCN))
1120 				cnp->cn_flags |= SAVENAME;
1121 			return (0);
1122 		}
1123 		cache_purge(newvp);
1124 		if (dvp != newvp)
1125 			vput(newvp);
1126 		else
1127 			vrele(newvp);
1128 		*vpp = NULLVP;
1129 	} else if (error == ENOENT) {
1130 		if (dvp->v_iflag & VI_DOOMED)
1131 			return (ENOENT);
1132 		/*
1133 		 * We only accept a negative hit in the cache if the
1134 		 * modification time of the parent directory matches
1135 		 * the cached copy in the name cache entry.
1136 		 * Otherwise, we discard all of the negative cache
1137 		 * entries for this directory.  We also only trust
1138 		 * negative cache entries for up to nm_negnametimeo
1139 		 * seconds.
1140 		 */
1141 		if ((u_int)(ticks - ncticks) < (nmp->nm_negnametimeo * hz) &&
1142 		    VOP_GETATTR(dvp, &vattr, cnp->cn_cred) == 0 &&
1143 		    timespeccmp(&vattr.va_mtime, &nctime, ==)) {
1144 			NFSINCRGLOBAL(newnfsstats.lookupcache_hits);
1145 			return (ENOENT);
1146 		}
1147 		cache_purge_negative(dvp);
1148 	}
1149 
1150 	error = 0;
1151 	newvp = NULLVP;
1152 	NFSINCRGLOBAL(newnfsstats.lookupcache_misses);
1153 	error = nfsrpc_lookup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
1154 	    cnp->cn_cred, td, &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag,
1155 	    NULL);
1156 	if (dattrflag)
1157 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
1158 	if (error) {
1159 		if (newvp != NULLVP) {
1160 			vput(newvp);
1161 			*vpp = NULLVP;
1162 		}
1163 
1164 		if (error != ENOENT) {
1165 			if (NFS_ISV4(dvp))
1166 				error = nfscl_maperr(td, error, (uid_t)0,
1167 				    (gid_t)0);
1168 			return (error);
1169 		}
1170 
1171 		/* The requested file was not found. */
1172 		if ((cnp->cn_nameiop == CREATE || cnp->cn_nameiop == RENAME) &&
1173 		    (flags & ISLASTCN)) {
1174 			/*
1175 			 * XXX: UFS does a full VOP_ACCESS(dvp,
1176 			 * VWRITE) here instead of just checking
1177 			 * MNT_RDONLY.
1178 			 */
1179 			if (mp->mnt_flag & MNT_RDONLY)
1180 				return (EROFS);
1181 			cnp->cn_flags |= SAVENAME;
1182 			return (EJUSTRETURN);
1183 		}
1184 
1185 		if ((cnp->cn_flags & MAKEENTRY) != 0 && dattrflag) {
1186 			/*
1187 			 * Cache the modification time of the parent
1188 			 * directory from the post-op attributes in
1189 			 * the name cache entry.  The negative cache
1190 			 * entry will be ignored once the directory
1191 			 * has changed.  Don't bother adding the entry
1192 			 * if the directory has already changed.
1193 			 */
1194 			mtx_lock(&np->n_mtx);
1195 			if (timespeccmp(&np->n_vattr.na_mtime,
1196 			    &dnfsva.na_mtime, ==)) {
1197 				mtx_unlock(&np->n_mtx);
1198 				cache_enter_time(dvp, NULL, cnp,
1199 				    &dnfsva.na_mtime, NULL);
1200 			} else
1201 				mtx_unlock(&np->n_mtx);
1202 		}
1203 		return (ENOENT);
1204 	}
1205 
1206 	/*
1207 	 * Handle RENAME case...
1208 	 */
1209 	if (cnp->cn_nameiop == RENAME && (flags & ISLASTCN)) {
1210 		if (NFS_CMPFH(np, nfhp->nfh_fh, nfhp->nfh_len)) {
1211 			FREE((caddr_t)nfhp, M_NFSFH);
1212 			return (EISDIR);
1213 		}
1214 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np, NULL,
1215 		    LK_EXCLUSIVE);
1216 		if (error)
1217 			return (error);
1218 		newvp = NFSTOV(np);
1219 		if (attrflag)
1220 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1221 			    0, 1);
1222 		*vpp = newvp;
1223 		cnp->cn_flags |= SAVENAME;
1224 		return (0);
1225 	}
1226 
1227 	if (flags & ISDOTDOT) {
1228 		ltype = NFSVOPISLOCKED(dvp);
1229 		error = vfs_busy(mp, MBF_NOWAIT);
1230 		if (error != 0) {
1231 			vfs_ref(mp);
1232 			NFSVOPUNLOCK(dvp, 0);
1233 			error = vfs_busy(mp, 0);
1234 			NFSVOPLOCK(dvp, ltype | LK_RETRY);
1235 			vfs_rel(mp);
1236 			if (error == 0 && (dvp->v_iflag & VI_DOOMED)) {
1237 				vfs_unbusy(mp);
1238 				error = ENOENT;
1239 			}
1240 			if (error != 0)
1241 				return (error);
1242 		}
1243 		NFSVOPUNLOCK(dvp, 0);
1244 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np, NULL,
1245 		    cnp->cn_lkflags);
1246 		if (error == 0)
1247 			newvp = NFSTOV(np);
1248 		vfs_unbusy(mp);
1249 		if (newvp != dvp)
1250 			NFSVOPLOCK(dvp, ltype | LK_RETRY);
1251 		if (dvp->v_iflag & VI_DOOMED) {
1252 			if (error == 0) {
1253 				if (newvp == dvp)
1254 					vrele(newvp);
1255 				else
1256 					vput(newvp);
1257 			}
1258 			error = ENOENT;
1259 		}
1260 		if (error != 0)
1261 			return (error);
1262 		if (attrflag)
1263 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1264 			    0, 1);
1265 	} else if (NFS_CMPFH(np, nfhp->nfh_fh, nfhp->nfh_len)) {
1266 		FREE((caddr_t)nfhp, M_NFSFH);
1267 		VREF(dvp);
1268 		newvp = dvp;
1269 		if (attrflag)
1270 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1271 			    0, 1);
1272 	} else {
1273 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np, NULL,
1274 		    cnp->cn_lkflags);
1275 		if (error)
1276 			return (error);
1277 		newvp = NFSTOV(np);
1278 		if (attrflag)
1279 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1280 			    0, 1);
1281 		else if ((flags & (ISLASTCN | ISOPEN)) == (ISLASTCN | ISOPEN) &&
1282 		    !(np->n_flag & NMODIFIED)) {
1283 			/*
1284 			 * Flush the attribute cache when opening a
1285 			 * leaf node to ensure that fresh attributes
1286 			 * are fetched in nfs_open() since we did not
1287 			 * fetch attributes from the LOOKUP reply.
1288 			 */
1289 			mtx_lock(&np->n_mtx);
1290 			np->n_attrstamp = 0;
1291 			KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(newvp);
1292 			mtx_unlock(&np->n_mtx);
1293 		}
1294 	}
1295 	if (cnp->cn_nameiop != LOOKUP && (flags & ISLASTCN))
1296 		cnp->cn_flags |= SAVENAME;
1297 	if ((cnp->cn_flags & MAKEENTRY) &&
1298 	    (cnp->cn_nameiop != DELETE || !(flags & ISLASTCN)) &&
1299 	    attrflag != 0 && (newvp->v_type != VDIR || dattrflag != 0))
1300 		cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime,
1301 		    newvp->v_type != VDIR ? NULL : &dnfsva.na_ctime);
1302 	*vpp = newvp;
1303 	return (0);
1304 }
1305 
1306 /*
1307  * nfs read call.
1308  * Just call ncl_bioread() to do the work.
1309  */
1310 static int
1311 nfs_read(struct vop_read_args *ap)
1312 {
1313 	struct vnode *vp = ap->a_vp;
1314 
1315 	switch (vp->v_type) {
1316 	case VREG:
1317 		return (ncl_bioread(vp, ap->a_uio, ap->a_ioflag, ap->a_cred));
1318 	case VDIR:
1319 		return (EISDIR);
1320 	default:
1321 		return (EOPNOTSUPP);
1322 	}
1323 }
1324 
1325 /*
1326  * nfs readlink call
1327  */
1328 static int
1329 nfs_readlink(struct vop_readlink_args *ap)
1330 {
1331 	struct vnode *vp = ap->a_vp;
1332 
1333 	if (vp->v_type != VLNK)
1334 		return (EINVAL);
1335 	return (ncl_bioread(vp, ap->a_uio, 0, ap->a_cred));
1336 }
1337 
1338 /*
1339  * Do a readlink rpc.
1340  * Called by ncl_doio() from below the buffer cache.
1341  */
1342 int
1343 ncl_readlinkrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred)
1344 {
1345 	int error, ret, attrflag;
1346 	struct nfsvattr nfsva;
1347 
1348 	error = nfsrpc_readlink(vp, uiop, cred, uiop->uio_td, &nfsva,
1349 	    &attrflag, NULL);
1350 	if (attrflag) {
1351 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
1352 		if (ret && !error)
1353 			error = ret;
1354 	}
1355 	if (error && NFS_ISV4(vp))
1356 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1357 	return (error);
1358 }
1359 
1360 /*
1361  * nfs read rpc call
1362  * Ditto above
1363  */
1364 int
1365 ncl_readrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred)
1366 {
1367 	int error, ret, attrflag;
1368 	struct nfsvattr nfsva;
1369 	struct nfsmount *nmp;
1370 
1371 	nmp = VFSTONFS(vnode_mount(vp));
1372 	error = EIO;
1373 	attrflag = 0;
1374 	if (NFSHASPNFS(nmp))
1375 		error = nfscl_doiods(vp, uiop, NULL, NULL,
1376 		    NFSV4OPEN_ACCESSREAD, cred, uiop->uio_td);
1377 	NFSCL_DEBUG(4, "readrpc: aft doiods=%d\n", error);
1378 	if (error != 0)
1379 		error = nfsrpc_read(vp, uiop, cred, uiop->uio_td, &nfsva,
1380 		    &attrflag, NULL);
1381 	if (attrflag) {
1382 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
1383 		if (ret && !error)
1384 			error = ret;
1385 	}
1386 	if (error && NFS_ISV4(vp))
1387 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1388 	return (error);
1389 }
1390 
1391 /*
1392  * nfs write call
1393  */
1394 int
1395 ncl_writerpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
1396     int *iomode, int *must_commit, int called_from_strategy)
1397 {
1398 	struct nfsvattr nfsva;
1399 	int error, attrflag, ret;
1400 	struct nfsmount *nmp;
1401 
1402 	nmp = VFSTONFS(vnode_mount(vp));
1403 	error = EIO;
1404 	attrflag = 0;
1405 	if (NFSHASPNFS(nmp))
1406 		error = nfscl_doiods(vp, uiop, iomode, must_commit,
1407 		    NFSV4OPEN_ACCESSWRITE, cred, uiop->uio_td);
1408 	NFSCL_DEBUG(4, "writerpc: aft doiods=%d\n", error);
1409 	if (error != 0)
1410 		error = nfsrpc_write(vp, uiop, iomode, must_commit, cred,
1411 		    uiop->uio_td, &nfsva, &attrflag, NULL,
1412 		    called_from_strategy);
1413 	if (attrflag) {
1414 		if (VTONFS(vp)->n_flag & ND_NFSV4)
1415 			ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 1,
1416 			    1);
1417 		else
1418 			ret = nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0,
1419 			    1);
1420 		if (ret && !error)
1421 			error = ret;
1422 	}
1423 	if (DOINGASYNC(vp))
1424 		*iomode = NFSWRITE_FILESYNC;
1425 	if (error && NFS_ISV4(vp))
1426 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1427 	return (error);
1428 }
1429 
1430 /*
1431  * nfs mknod rpc
1432  * For NFS v2 this is a kludge. Use a create rpc but with the IFMT bits of the
1433  * mode set to specify the file type and the size field for rdev.
1434  */
1435 static int
1436 nfs_mknodrpc(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp,
1437     struct vattr *vap)
1438 {
1439 	struct nfsvattr nfsva, dnfsva;
1440 	struct vnode *newvp = NULL;
1441 	struct nfsnode *np = NULL, *dnp;
1442 	struct nfsfh *nfhp;
1443 	struct vattr vattr;
1444 	int error = 0, attrflag, dattrflag;
1445 	u_int32_t rdev;
1446 
1447 	if (vap->va_type == VCHR || vap->va_type == VBLK)
1448 		rdev = vap->va_rdev;
1449 	else if (vap->va_type == VFIFO || vap->va_type == VSOCK)
1450 		rdev = 0xffffffff;
1451 	else
1452 		return (EOPNOTSUPP);
1453 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)))
1454 		return (error);
1455 	error = nfsrpc_mknod(dvp, cnp->cn_nameptr, cnp->cn_namelen, vap,
1456 	    rdev, vap->va_type, cnp->cn_cred, cnp->cn_thread, &dnfsva,
1457 	    &nfsva, &nfhp, &attrflag, &dattrflag, NULL);
1458 	if (!error) {
1459 		if (!nfhp)
1460 			(void) nfsrpc_lookup(dvp, cnp->cn_nameptr,
1461 			    cnp->cn_namelen, cnp->cn_cred, cnp->cn_thread,
1462 			    &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag,
1463 			    NULL);
1464 		if (nfhp)
1465 			error = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp,
1466 			    cnp->cn_thread, &np, NULL, LK_EXCLUSIVE);
1467 	}
1468 	if (dattrflag)
1469 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
1470 	if (!error) {
1471 		newvp = NFSTOV(np);
1472 		if (attrflag != 0) {
1473 			error = nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1474 			    0, 1);
1475 			if (error != 0)
1476 				vput(newvp);
1477 		}
1478 	}
1479 	if (!error) {
1480 		*vpp = newvp;
1481 	} else if (NFS_ISV4(dvp)) {
1482 		error = nfscl_maperr(cnp->cn_thread, error, vap->va_uid,
1483 		    vap->va_gid);
1484 	}
1485 	dnp = VTONFS(dvp);
1486 	mtx_lock(&dnp->n_mtx);
1487 	dnp->n_flag |= NMODIFIED;
1488 	if (!dattrflag) {
1489 		dnp->n_attrstamp = 0;
1490 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1491 	}
1492 	mtx_unlock(&dnp->n_mtx);
1493 	return (error);
1494 }
1495 
1496 /*
1497  * nfs mknod vop
1498  * just call nfs_mknodrpc() to do the work.
1499  */
1500 /* ARGSUSED */
1501 static int
1502 nfs_mknod(struct vop_mknod_args *ap)
1503 {
1504 	return (nfs_mknodrpc(ap->a_dvp, ap->a_vpp, ap->a_cnp, ap->a_vap));
1505 }
1506 
1507 static struct mtx nfs_cverf_mtx;
1508 MTX_SYSINIT(nfs_cverf_mtx, &nfs_cverf_mtx, "NFS create verifier mutex",
1509     MTX_DEF);
1510 
1511 static nfsquad_t
1512 nfs_get_cverf(void)
1513 {
1514 	static nfsquad_t cverf;
1515 	nfsquad_t ret;
1516 	static int cverf_initialized = 0;
1517 
1518 	mtx_lock(&nfs_cverf_mtx);
1519 	if (cverf_initialized == 0) {
1520 		cverf.lval[0] = arc4random();
1521 		cverf.lval[1] = arc4random();
1522 		cverf_initialized = 1;
1523 	} else
1524 		cverf.qval++;
1525 	ret = cverf;
1526 	mtx_unlock(&nfs_cverf_mtx);
1527 
1528 	return (ret);
1529 }
1530 
1531 /*
1532  * nfs file create call
1533  */
1534 static int
1535 nfs_create(struct vop_create_args *ap)
1536 {
1537 	struct vnode *dvp = ap->a_dvp;
1538 	struct vattr *vap = ap->a_vap;
1539 	struct componentname *cnp = ap->a_cnp;
1540 	struct nfsnode *np = NULL, *dnp;
1541 	struct vnode *newvp = NULL;
1542 	struct nfsmount *nmp;
1543 	struct nfsvattr dnfsva, nfsva;
1544 	struct nfsfh *nfhp;
1545 	nfsquad_t cverf;
1546 	int error = 0, attrflag, dattrflag, fmode = 0;
1547 	struct vattr vattr;
1548 
1549 	/*
1550 	 * Oops, not for me..
1551 	 */
1552 	if (vap->va_type == VSOCK)
1553 		return (nfs_mknodrpc(dvp, ap->a_vpp, cnp, vap));
1554 
1555 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)))
1556 		return (error);
1557 	if (vap->va_vaflags & VA_EXCLUSIVE)
1558 		fmode |= O_EXCL;
1559 	dnp = VTONFS(dvp);
1560 	nmp = VFSTONFS(vnode_mount(dvp));
1561 again:
1562 	/* For NFSv4, wait until any remove is done. */
1563 	mtx_lock(&dnp->n_mtx);
1564 	while (NFSHASNFSV4(nmp) && (dnp->n_flag & NREMOVEINPROG)) {
1565 		dnp->n_flag |= NREMOVEWANT;
1566 		(void) msleep((caddr_t)dnp, &dnp->n_mtx, PZERO, "nfscrt", 0);
1567 	}
1568 	mtx_unlock(&dnp->n_mtx);
1569 
1570 	cverf = nfs_get_cverf();
1571 	error = nfsrpc_create(dvp, cnp->cn_nameptr, cnp->cn_namelen,
1572 	    vap, cverf, fmode, cnp->cn_cred, cnp->cn_thread, &dnfsva, &nfsva,
1573 	    &nfhp, &attrflag, &dattrflag, NULL);
1574 	if (!error) {
1575 		if (nfhp == NULL)
1576 			(void) nfsrpc_lookup(dvp, cnp->cn_nameptr,
1577 			    cnp->cn_namelen, cnp->cn_cred, cnp->cn_thread,
1578 			    &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag,
1579 			    NULL);
1580 		if (nfhp != NULL)
1581 			error = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp,
1582 			    cnp->cn_thread, &np, NULL, LK_EXCLUSIVE);
1583 	}
1584 	if (dattrflag)
1585 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
1586 	if (!error) {
1587 		newvp = NFSTOV(np);
1588 		if (attrflag == 0)
1589 			error = nfsrpc_getattr(newvp, cnp->cn_cred,
1590 			    cnp->cn_thread, &nfsva, NULL);
1591 		if (error == 0)
1592 			error = nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
1593 			    0, 1);
1594 	}
1595 	if (error) {
1596 		if (newvp != NULL) {
1597 			vput(newvp);
1598 			newvp = NULL;
1599 		}
1600 		if (NFS_ISV34(dvp) && (fmode & O_EXCL) &&
1601 		    error == NFSERR_NOTSUPP) {
1602 			fmode &= ~O_EXCL;
1603 			goto again;
1604 		}
1605 	} else if (NFS_ISV34(dvp) && (fmode & O_EXCL)) {
1606 		if (nfscl_checksattr(vap, &nfsva)) {
1607 			error = nfsrpc_setattr(newvp, vap, NULL, cnp->cn_cred,
1608 			    cnp->cn_thread, &nfsva, &attrflag, NULL);
1609 			if (error && (vap->va_uid != (uid_t)VNOVAL ||
1610 			    vap->va_gid != (gid_t)VNOVAL)) {
1611 				/* try again without setting uid/gid */
1612 				vap->va_uid = (uid_t)VNOVAL;
1613 				vap->va_gid = (uid_t)VNOVAL;
1614 				error = nfsrpc_setattr(newvp, vap, NULL,
1615 				    cnp->cn_cred, cnp->cn_thread, &nfsva,
1616 				    &attrflag, NULL);
1617 			}
1618 			if (attrflag)
1619 				(void) nfscl_loadattrcache(&newvp, &nfsva, NULL,
1620 				    NULL, 0, 1);
1621 			if (error != 0)
1622 				vput(newvp);
1623 		}
1624 	}
1625 	if (!error) {
1626 		if ((cnp->cn_flags & MAKEENTRY) && attrflag)
1627 			cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime,
1628 			    NULL);
1629 		*ap->a_vpp = newvp;
1630 	} else if (NFS_ISV4(dvp)) {
1631 		error = nfscl_maperr(cnp->cn_thread, error, vap->va_uid,
1632 		    vap->va_gid);
1633 	}
1634 	mtx_lock(&dnp->n_mtx);
1635 	dnp->n_flag |= NMODIFIED;
1636 	if (!dattrflag) {
1637 		dnp->n_attrstamp = 0;
1638 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1639 	}
1640 	mtx_unlock(&dnp->n_mtx);
1641 	return (error);
1642 }
1643 
1644 /*
1645  * nfs file remove call
1646  * To try and make nfs semantics closer to ufs semantics, a file that has
1647  * other processes using the vnode is renamed instead of removed and then
1648  * removed later on the last close.
1649  * - If v_usecount > 1
1650  *	  If a rename is not already in the works
1651  *	     call nfs_sillyrename() to set it up
1652  *     else
1653  *	  do the remove rpc
1654  */
1655 static int
1656 nfs_remove(struct vop_remove_args *ap)
1657 {
1658 	struct vnode *vp = ap->a_vp;
1659 	struct vnode *dvp = ap->a_dvp;
1660 	struct componentname *cnp = ap->a_cnp;
1661 	struct nfsnode *np = VTONFS(vp);
1662 	int error = 0;
1663 	struct vattr vattr;
1664 
1665 	KASSERT((cnp->cn_flags & HASBUF) != 0, ("nfs_remove: no name"));
1666 	KASSERT(vrefcnt(vp) > 0, ("nfs_remove: bad v_usecount"));
1667 	if (vp->v_type == VDIR)
1668 		error = EPERM;
1669 	else if (vrefcnt(vp) == 1 || (np->n_sillyrename &&
1670 	    VOP_GETATTR(vp, &vattr, cnp->cn_cred) == 0 &&
1671 	    vattr.va_nlink > 1)) {
1672 		/*
1673 		 * Purge the name cache so that the chance of a lookup for
1674 		 * the name succeeding while the remove is in progress is
1675 		 * minimized. Without node locking it can still happen, such
1676 		 * that an I/O op returns ESTALE, but since you get this if
1677 		 * another host removes the file..
1678 		 */
1679 		cache_purge(vp);
1680 		/*
1681 		 * throw away biocache buffers, mainly to avoid
1682 		 * unnecessary delayed writes later.
1683 		 */
1684 		error = ncl_vinvalbuf(vp, 0, cnp->cn_thread, 1);
1685 		/* Do the rpc */
1686 		if (error != EINTR && error != EIO)
1687 			error = nfs_removerpc(dvp, vp, cnp->cn_nameptr,
1688 			    cnp->cn_namelen, cnp->cn_cred, cnp->cn_thread);
1689 		/*
1690 		 * Kludge City: If the first reply to the remove rpc is lost..
1691 		 *   the reply to the retransmitted request will be ENOENT
1692 		 *   since the file was in fact removed
1693 		 *   Therefore, we cheat and return success.
1694 		 */
1695 		if (error == ENOENT)
1696 			error = 0;
1697 	} else if (!np->n_sillyrename)
1698 		error = nfs_sillyrename(dvp, vp, cnp);
1699 	mtx_lock(&np->n_mtx);
1700 	np->n_attrstamp = 0;
1701 	mtx_unlock(&np->n_mtx);
1702 	KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
1703 	return (error);
1704 }
1705 
1706 /*
1707  * nfs file remove rpc called from nfs_inactive
1708  */
1709 int
1710 ncl_removeit(struct sillyrename *sp, struct vnode *vp)
1711 {
1712 	/*
1713 	 * Make sure that the directory vnode is still valid.
1714 	 * XXX we should lock sp->s_dvp here.
1715 	 */
1716 	if (sp->s_dvp->v_type == VBAD)
1717 		return (0);
1718 	return (nfs_removerpc(sp->s_dvp, vp, sp->s_name, sp->s_namlen,
1719 	    sp->s_cred, NULL));
1720 }
1721 
1722 /*
1723  * Nfs remove rpc, called from nfs_remove() and ncl_removeit().
1724  */
1725 static int
1726 nfs_removerpc(struct vnode *dvp, struct vnode *vp, char *name,
1727     int namelen, struct ucred *cred, struct thread *td)
1728 {
1729 	struct nfsvattr dnfsva;
1730 	struct nfsnode *dnp = VTONFS(dvp);
1731 	int error = 0, dattrflag;
1732 
1733 	mtx_lock(&dnp->n_mtx);
1734 	dnp->n_flag |= NREMOVEINPROG;
1735 	mtx_unlock(&dnp->n_mtx);
1736 	error = nfsrpc_remove(dvp, name, namelen, vp, cred, td, &dnfsva,
1737 	    &dattrflag, NULL);
1738 	mtx_lock(&dnp->n_mtx);
1739 	if ((dnp->n_flag & NREMOVEWANT)) {
1740 		dnp->n_flag &= ~(NREMOVEWANT | NREMOVEINPROG);
1741 		mtx_unlock(&dnp->n_mtx);
1742 		wakeup((caddr_t)dnp);
1743 	} else {
1744 		dnp->n_flag &= ~NREMOVEINPROG;
1745 		mtx_unlock(&dnp->n_mtx);
1746 	}
1747 	if (dattrflag)
1748 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
1749 	mtx_lock(&dnp->n_mtx);
1750 	dnp->n_flag |= NMODIFIED;
1751 	if (!dattrflag) {
1752 		dnp->n_attrstamp = 0;
1753 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1754 	}
1755 	mtx_unlock(&dnp->n_mtx);
1756 	if (error && NFS_ISV4(dvp))
1757 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
1758 	return (error);
1759 }
1760 
1761 /*
1762  * nfs file rename call
1763  */
1764 static int
1765 nfs_rename(struct vop_rename_args *ap)
1766 {
1767 	struct vnode *fvp = ap->a_fvp;
1768 	struct vnode *tvp = ap->a_tvp;
1769 	struct vnode *fdvp = ap->a_fdvp;
1770 	struct vnode *tdvp = ap->a_tdvp;
1771 	struct componentname *tcnp = ap->a_tcnp;
1772 	struct componentname *fcnp = ap->a_fcnp;
1773 	struct nfsnode *fnp = VTONFS(ap->a_fvp);
1774 	struct nfsnode *tdnp = VTONFS(ap->a_tdvp);
1775 	struct nfsv4node *newv4 = NULL;
1776 	int error;
1777 
1778 	KASSERT((tcnp->cn_flags & HASBUF) != 0 &&
1779 	    (fcnp->cn_flags & HASBUF) != 0, ("nfs_rename: no name"));
1780 	/* Check for cross-device rename */
1781 	if ((fvp->v_mount != tdvp->v_mount) ||
1782 	    (tvp && (fvp->v_mount != tvp->v_mount))) {
1783 		error = EXDEV;
1784 		goto out;
1785 	}
1786 
1787 	if (fvp == tvp) {
1788 		ncl_printf("nfs_rename: fvp == tvp (can't happen)\n");
1789 		error = 0;
1790 		goto out;
1791 	}
1792 	if ((error = NFSVOPLOCK(fvp, LK_EXCLUSIVE)) != 0)
1793 		goto out;
1794 
1795 	/*
1796 	 * We have to flush B_DELWRI data prior to renaming
1797 	 * the file.  If we don't, the delayed-write buffers
1798 	 * can be flushed out later after the file has gone stale
1799 	 * under NFSV3.  NFSV2 does not have this problem because
1800 	 * ( as far as I can tell ) it flushes dirty buffers more
1801 	 * often.
1802 	 *
1803 	 * Skip the rename operation if the fsync fails, this can happen
1804 	 * due to the server's volume being full, when we pushed out data
1805 	 * that was written back to our cache earlier. Not checking for
1806 	 * this condition can result in potential (silent) data loss.
1807 	 */
1808 	error = VOP_FSYNC(fvp, MNT_WAIT, fcnp->cn_thread);
1809 	NFSVOPUNLOCK(fvp, 0);
1810 	if (!error && tvp)
1811 		error = VOP_FSYNC(tvp, MNT_WAIT, tcnp->cn_thread);
1812 	if (error)
1813 		goto out;
1814 
1815 	/*
1816 	 * If the tvp exists and is in use, sillyrename it before doing the
1817 	 * rename of the new file over it.
1818 	 * XXX Can't sillyrename a directory.
1819 	 */
1820 	if (tvp && vrefcnt(tvp) > 1 && !VTONFS(tvp)->n_sillyrename &&
1821 		tvp->v_type != VDIR && !nfs_sillyrename(tdvp, tvp, tcnp)) {
1822 		vput(tvp);
1823 		tvp = NULL;
1824 	}
1825 
1826 	error = nfs_renamerpc(fdvp, fvp, fcnp->cn_nameptr, fcnp->cn_namelen,
1827 	    tdvp, tvp, tcnp->cn_nameptr, tcnp->cn_namelen, tcnp->cn_cred,
1828 	    tcnp->cn_thread);
1829 
1830 	if (error == 0 && NFS_ISV4(tdvp)) {
1831 		/*
1832 		 * For NFSv4, check to see if it is the same name and
1833 		 * replace the name, if it is different.
1834 		 */
1835 		MALLOC(newv4, struct nfsv4node *,
1836 		    sizeof (struct nfsv4node) +
1837 		    tdnp->n_fhp->nfh_len + tcnp->cn_namelen - 1,
1838 		    M_NFSV4NODE, M_WAITOK);
1839 		mtx_lock(&tdnp->n_mtx);
1840 		mtx_lock(&fnp->n_mtx);
1841 		if (fnp->n_v4 != NULL && fvp->v_type == VREG &&
1842 		    (fnp->n_v4->n4_namelen != tcnp->cn_namelen ||
1843 		      NFSBCMP(tcnp->cn_nameptr, NFS4NODENAME(fnp->n_v4),
1844 		      tcnp->cn_namelen) ||
1845 		      tdnp->n_fhp->nfh_len != fnp->n_v4->n4_fhlen ||
1846 		      NFSBCMP(tdnp->n_fhp->nfh_fh, fnp->n_v4->n4_data,
1847 			tdnp->n_fhp->nfh_len))) {
1848 #ifdef notdef
1849 { char nnn[100]; int nnnl;
1850 nnnl = (tcnp->cn_namelen < 100) ? tcnp->cn_namelen : 99;
1851 bcopy(tcnp->cn_nameptr, nnn, nnnl);
1852 nnn[nnnl] = '\0';
1853 printf("ren replace=%s\n",nnn);
1854 }
1855 #endif
1856 			FREE((caddr_t)fnp->n_v4, M_NFSV4NODE);
1857 			fnp->n_v4 = newv4;
1858 			newv4 = NULL;
1859 			fnp->n_v4->n4_fhlen = tdnp->n_fhp->nfh_len;
1860 			fnp->n_v4->n4_namelen = tcnp->cn_namelen;
1861 			NFSBCOPY(tdnp->n_fhp->nfh_fh, fnp->n_v4->n4_data,
1862 			    tdnp->n_fhp->nfh_len);
1863 			NFSBCOPY(tcnp->cn_nameptr,
1864 			    NFS4NODENAME(fnp->n_v4), tcnp->cn_namelen);
1865 		}
1866 		mtx_unlock(&tdnp->n_mtx);
1867 		mtx_unlock(&fnp->n_mtx);
1868 		if (newv4 != NULL)
1869 			FREE((caddr_t)newv4, M_NFSV4NODE);
1870 	}
1871 
1872 	if (fvp->v_type == VDIR) {
1873 		if (tvp != NULL && tvp->v_type == VDIR)
1874 			cache_purge(tdvp);
1875 		cache_purge(fdvp);
1876 	}
1877 
1878 out:
1879 	if (tdvp == tvp)
1880 		vrele(tdvp);
1881 	else
1882 		vput(tdvp);
1883 	if (tvp)
1884 		vput(tvp);
1885 	vrele(fdvp);
1886 	vrele(fvp);
1887 	/*
1888 	 * Kludge: Map ENOENT => 0 assuming that it is a reply to a retry.
1889 	 */
1890 	if (error == ENOENT)
1891 		error = 0;
1892 	return (error);
1893 }
1894 
1895 /*
1896  * nfs file rename rpc called from nfs_remove() above
1897  */
1898 static int
1899 nfs_renameit(struct vnode *sdvp, struct vnode *svp, struct componentname *scnp,
1900     struct sillyrename *sp)
1901 {
1902 
1903 	return (nfs_renamerpc(sdvp, svp, scnp->cn_nameptr, scnp->cn_namelen,
1904 	    sdvp, NULL, sp->s_name, sp->s_namlen, scnp->cn_cred,
1905 	    scnp->cn_thread));
1906 }
1907 
1908 /*
1909  * Do an nfs rename rpc. Called from nfs_rename() and nfs_renameit().
1910  */
1911 static int
1912 nfs_renamerpc(struct vnode *fdvp, struct vnode *fvp, char *fnameptr,
1913     int fnamelen, struct vnode *tdvp, struct vnode *tvp, char *tnameptr,
1914     int tnamelen, struct ucred *cred, struct thread *td)
1915 {
1916 	struct nfsvattr fnfsva, tnfsva;
1917 	struct nfsnode *fdnp = VTONFS(fdvp);
1918 	struct nfsnode *tdnp = VTONFS(tdvp);
1919 	int error = 0, fattrflag, tattrflag;
1920 
1921 	error = nfsrpc_rename(fdvp, fvp, fnameptr, fnamelen, tdvp, tvp,
1922 	    tnameptr, tnamelen, cred, td, &fnfsva, &tnfsva, &fattrflag,
1923 	    &tattrflag, NULL, NULL);
1924 	mtx_lock(&fdnp->n_mtx);
1925 	fdnp->n_flag |= NMODIFIED;
1926 	if (fattrflag != 0) {
1927 		mtx_unlock(&fdnp->n_mtx);
1928 		(void) nfscl_loadattrcache(&fdvp, &fnfsva, NULL, NULL, 0, 1);
1929 	} else {
1930 		fdnp->n_attrstamp = 0;
1931 		mtx_unlock(&fdnp->n_mtx);
1932 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(fdvp);
1933 	}
1934 	mtx_lock(&tdnp->n_mtx);
1935 	tdnp->n_flag |= NMODIFIED;
1936 	if (tattrflag != 0) {
1937 		mtx_unlock(&tdnp->n_mtx);
1938 		(void) nfscl_loadattrcache(&tdvp, &tnfsva, NULL, NULL, 0, 1);
1939 	} else {
1940 		tdnp->n_attrstamp = 0;
1941 		mtx_unlock(&tdnp->n_mtx);
1942 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(tdvp);
1943 	}
1944 	if (error && NFS_ISV4(fdvp))
1945 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
1946 	return (error);
1947 }
1948 
1949 /*
1950  * nfs hard link create call
1951  */
1952 static int
1953 nfs_link(struct vop_link_args *ap)
1954 {
1955 	struct vnode *vp = ap->a_vp;
1956 	struct vnode *tdvp = ap->a_tdvp;
1957 	struct componentname *cnp = ap->a_cnp;
1958 	struct nfsnode *np, *tdnp;
1959 	struct nfsvattr nfsva, dnfsva;
1960 	int error = 0, attrflag, dattrflag;
1961 
1962 	/*
1963 	 * Push all writes to the server, so that the attribute cache
1964 	 * doesn't get "out of sync" with the server.
1965 	 * XXX There should be a better way!
1966 	 */
1967 	VOP_FSYNC(vp, MNT_WAIT, cnp->cn_thread);
1968 
1969 	error = nfsrpc_link(tdvp, vp, cnp->cn_nameptr, cnp->cn_namelen,
1970 	    cnp->cn_cred, cnp->cn_thread, &dnfsva, &nfsva, &attrflag,
1971 	    &dattrflag, NULL);
1972 	tdnp = VTONFS(tdvp);
1973 	mtx_lock(&tdnp->n_mtx);
1974 	tdnp->n_flag |= NMODIFIED;
1975 	if (dattrflag != 0) {
1976 		mtx_unlock(&tdnp->n_mtx);
1977 		(void) nfscl_loadattrcache(&tdvp, &dnfsva, NULL, NULL, 0, 1);
1978 	} else {
1979 		tdnp->n_attrstamp = 0;
1980 		mtx_unlock(&tdnp->n_mtx);
1981 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(tdvp);
1982 	}
1983 	if (attrflag)
1984 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
1985 	else {
1986 		np = VTONFS(vp);
1987 		mtx_lock(&np->n_mtx);
1988 		np->n_attrstamp = 0;
1989 		mtx_unlock(&np->n_mtx);
1990 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
1991 	}
1992 	/*
1993 	 * If negative lookup caching is enabled, I might as well
1994 	 * add an entry for this node. Not necessary for correctness,
1995 	 * but if negative caching is enabled, then the system
1996 	 * must care about lookup caching hit rate, so...
1997 	 */
1998 	if (VFSTONFS(vp->v_mount)->nm_negnametimeo != 0 &&
1999 	    (cnp->cn_flags & MAKEENTRY) && attrflag != 0 && error == 0) {
2000 		cache_enter_time(tdvp, vp, cnp, &nfsva.na_ctime, NULL);
2001 	}
2002 	if (error && NFS_ISV4(vp))
2003 		error = nfscl_maperr(cnp->cn_thread, error, (uid_t)0,
2004 		    (gid_t)0);
2005 	return (error);
2006 }
2007 
2008 /*
2009  * nfs symbolic link create call
2010  */
2011 static int
2012 nfs_symlink(struct vop_symlink_args *ap)
2013 {
2014 	struct vnode *dvp = ap->a_dvp;
2015 	struct vattr *vap = ap->a_vap;
2016 	struct componentname *cnp = ap->a_cnp;
2017 	struct nfsvattr nfsva, dnfsva;
2018 	struct nfsfh *nfhp;
2019 	struct nfsnode *np = NULL, *dnp;
2020 	struct vnode *newvp = NULL;
2021 	int error = 0, attrflag, dattrflag, ret;
2022 
2023 	vap->va_type = VLNK;
2024 	error = nfsrpc_symlink(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2025 	    ap->a_target, vap, cnp->cn_cred, cnp->cn_thread, &dnfsva,
2026 	    &nfsva, &nfhp, &attrflag, &dattrflag, NULL);
2027 	if (nfhp) {
2028 		ret = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp, cnp->cn_thread,
2029 		    &np, NULL, LK_EXCLUSIVE);
2030 		if (!ret)
2031 			newvp = NFSTOV(np);
2032 		else if (!error)
2033 			error = ret;
2034 	}
2035 	if (newvp != NULL) {
2036 		if (attrflag)
2037 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
2038 			    0, 1);
2039 	} else if (!error) {
2040 		/*
2041 		 * If we do not have an error and we could not extract the
2042 		 * newvp from the response due to the request being NFSv2, we
2043 		 * have to do a lookup in order to obtain a newvp to return.
2044 		 */
2045 		error = nfs_lookitup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2046 		    cnp->cn_cred, cnp->cn_thread, &np);
2047 		if (!error)
2048 			newvp = NFSTOV(np);
2049 	}
2050 	if (error) {
2051 		if (newvp)
2052 			vput(newvp);
2053 		if (NFS_ISV4(dvp))
2054 			error = nfscl_maperr(cnp->cn_thread, error,
2055 			    vap->va_uid, vap->va_gid);
2056 	} else {
2057 		*ap->a_vpp = newvp;
2058 	}
2059 
2060 	dnp = VTONFS(dvp);
2061 	mtx_lock(&dnp->n_mtx);
2062 	dnp->n_flag |= NMODIFIED;
2063 	if (dattrflag != 0) {
2064 		mtx_unlock(&dnp->n_mtx);
2065 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
2066 	} else {
2067 		dnp->n_attrstamp = 0;
2068 		mtx_unlock(&dnp->n_mtx);
2069 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2070 	}
2071 	/*
2072 	 * If negative lookup caching is enabled, I might as well
2073 	 * add an entry for this node. Not necessary for correctness,
2074 	 * but if negative caching is enabled, then the system
2075 	 * must care about lookup caching hit rate, so...
2076 	 */
2077 	if (VFSTONFS(dvp->v_mount)->nm_negnametimeo != 0 &&
2078 	    (cnp->cn_flags & MAKEENTRY) && attrflag != 0 && error == 0) {
2079 		cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime, NULL);
2080 	}
2081 	return (error);
2082 }
2083 
2084 /*
2085  * nfs make dir call
2086  */
2087 static int
2088 nfs_mkdir(struct vop_mkdir_args *ap)
2089 {
2090 	struct vnode *dvp = ap->a_dvp;
2091 	struct vattr *vap = ap->a_vap;
2092 	struct componentname *cnp = ap->a_cnp;
2093 	struct nfsnode *np = NULL, *dnp;
2094 	struct vnode *newvp = NULL;
2095 	struct vattr vattr;
2096 	struct nfsfh *nfhp;
2097 	struct nfsvattr nfsva, dnfsva;
2098 	int error = 0, attrflag, dattrflag, ret;
2099 
2100 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)) != 0)
2101 		return (error);
2102 	vap->va_type = VDIR;
2103 	error = nfsrpc_mkdir(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2104 	    vap, cnp->cn_cred, cnp->cn_thread, &dnfsva, &nfsva, &nfhp,
2105 	    &attrflag, &dattrflag, NULL);
2106 	dnp = VTONFS(dvp);
2107 	mtx_lock(&dnp->n_mtx);
2108 	dnp->n_flag |= NMODIFIED;
2109 	if (dattrflag != 0) {
2110 		mtx_unlock(&dnp->n_mtx);
2111 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
2112 	} else {
2113 		dnp->n_attrstamp = 0;
2114 		mtx_unlock(&dnp->n_mtx);
2115 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2116 	}
2117 	if (nfhp) {
2118 		ret = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp, cnp->cn_thread,
2119 		    &np, NULL, LK_EXCLUSIVE);
2120 		if (!ret) {
2121 			newvp = NFSTOV(np);
2122 			if (attrflag)
2123 			   (void) nfscl_loadattrcache(&newvp, &nfsva, NULL,
2124 				NULL, 0, 1);
2125 		} else if (!error)
2126 			error = ret;
2127 	}
2128 	if (!error && newvp == NULL) {
2129 		error = nfs_lookitup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2130 		    cnp->cn_cred, cnp->cn_thread, &np);
2131 		if (!error) {
2132 			newvp = NFSTOV(np);
2133 			if (newvp->v_type != VDIR)
2134 				error = EEXIST;
2135 		}
2136 	}
2137 	if (error) {
2138 		if (newvp)
2139 			vput(newvp);
2140 		if (NFS_ISV4(dvp))
2141 			error = nfscl_maperr(cnp->cn_thread, error,
2142 			    vap->va_uid, vap->va_gid);
2143 	} else {
2144 		/*
2145 		 * If negative lookup caching is enabled, I might as well
2146 		 * add an entry for this node. Not necessary for correctness,
2147 		 * but if negative caching is enabled, then the system
2148 		 * must care about lookup caching hit rate, so...
2149 		 */
2150 		if (VFSTONFS(dvp->v_mount)->nm_negnametimeo != 0 &&
2151 		    (cnp->cn_flags & MAKEENTRY) &&
2152 		    attrflag != 0 && dattrflag != 0)
2153 			cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime,
2154 			    &dnfsva.na_ctime);
2155 		*ap->a_vpp = newvp;
2156 	}
2157 	return (error);
2158 }
2159 
2160 /*
2161  * nfs remove directory call
2162  */
2163 static int
2164 nfs_rmdir(struct vop_rmdir_args *ap)
2165 {
2166 	struct vnode *vp = ap->a_vp;
2167 	struct vnode *dvp = ap->a_dvp;
2168 	struct componentname *cnp = ap->a_cnp;
2169 	struct nfsnode *dnp;
2170 	struct nfsvattr dnfsva;
2171 	int error, dattrflag;
2172 
2173 	if (dvp == vp)
2174 		return (EINVAL);
2175 	error = nfsrpc_rmdir(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2176 	    cnp->cn_cred, cnp->cn_thread, &dnfsva, &dattrflag, NULL);
2177 	dnp = VTONFS(dvp);
2178 	mtx_lock(&dnp->n_mtx);
2179 	dnp->n_flag |= NMODIFIED;
2180 	if (dattrflag != 0) {
2181 		mtx_unlock(&dnp->n_mtx);
2182 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
2183 	} else {
2184 		dnp->n_attrstamp = 0;
2185 		mtx_unlock(&dnp->n_mtx);
2186 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2187 	}
2188 
2189 	cache_purge(dvp);
2190 	cache_purge(vp);
2191 	if (error && NFS_ISV4(dvp))
2192 		error = nfscl_maperr(cnp->cn_thread, error, (uid_t)0,
2193 		    (gid_t)0);
2194 	/*
2195 	 * Kludge: Map ENOENT => 0 assuming that you have a reply to a retry.
2196 	 */
2197 	if (error == ENOENT)
2198 		error = 0;
2199 	return (error);
2200 }
2201 
2202 /*
2203  * nfs readdir call
2204  */
2205 static int
2206 nfs_readdir(struct vop_readdir_args *ap)
2207 {
2208 	struct vnode *vp = ap->a_vp;
2209 	struct nfsnode *np = VTONFS(vp);
2210 	struct uio *uio = ap->a_uio;
2211 	ssize_t tresid, left;
2212 	int error = 0;
2213 	struct vattr vattr;
2214 
2215 	if (ap->a_eofflag != NULL)
2216 		*ap->a_eofflag = 0;
2217 	if (vp->v_type != VDIR)
2218 		return(EPERM);
2219 
2220 	/*
2221 	 * First, check for hit on the EOF offset cache
2222 	 */
2223 	if (np->n_direofoffset > 0 && uio->uio_offset >= np->n_direofoffset &&
2224 	    (np->n_flag & NMODIFIED) == 0) {
2225 		if (VOP_GETATTR(vp, &vattr, ap->a_cred) == 0) {
2226 			mtx_lock(&np->n_mtx);
2227 			if ((NFS_ISV4(vp) && np->n_change == vattr.va_filerev) ||
2228 			    !NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime)) {
2229 				mtx_unlock(&np->n_mtx);
2230 				NFSINCRGLOBAL(newnfsstats.direofcache_hits);
2231 				if (ap->a_eofflag != NULL)
2232 					*ap->a_eofflag = 1;
2233 				return (0);
2234 			} else
2235 				mtx_unlock(&np->n_mtx);
2236 		}
2237 	}
2238 
2239 	/*
2240 	 * NFS always guarantees that directory entries don't straddle
2241 	 * DIRBLKSIZ boundaries.  As such, we need to limit the size
2242 	 * to an exact multiple of DIRBLKSIZ, to avoid copying a partial
2243 	 * directory entry.
2244 	 */
2245 	left = uio->uio_resid % DIRBLKSIZ;
2246 	if (left == uio->uio_resid)
2247 		return (EINVAL);
2248 	uio->uio_resid -= left;
2249 
2250 	/*
2251 	 * Call ncl_bioread() to do the real work.
2252 	 */
2253 	tresid = uio->uio_resid;
2254 	error = ncl_bioread(vp, uio, 0, ap->a_cred);
2255 
2256 	if (!error && uio->uio_resid == tresid) {
2257 		NFSINCRGLOBAL(newnfsstats.direofcache_misses);
2258 		if (ap->a_eofflag != NULL)
2259 			*ap->a_eofflag = 1;
2260 	}
2261 
2262 	/* Add the partial DIRBLKSIZ (left) back in. */
2263 	uio->uio_resid += left;
2264 	return (error);
2265 }
2266 
2267 /*
2268  * Readdir rpc call.
2269  * Called from below the buffer cache by ncl_doio().
2270  */
2271 int
2272 ncl_readdirrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
2273     struct thread *td)
2274 {
2275 	struct nfsvattr nfsva;
2276 	nfsuint64 *cookiep, cookie;
2277 	struct nfsnode *dnp = VTONFS(vp);
2278 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2279 	int error = 0, eof, attrflag;
2280 
2281 	KASSERT(uiop->uio_iovcnt == 1 &&
2282 	    (uiop->uio_offset & (DIRBLKSIZ - 1)) == 0 &&
2283 	    (uiop->uio_resid & (DIRBLKSIZ - 1)) == 0,
2284 	    ("nfs readdirrpc bad uio"));
2285 
2286 	/*
2287 	 * If there is no cookie, assume directory was stale.
2288 	 */
2289 	ncl_dircookie_lock(dnp);
2290 	cookiep = ncl_getcookie(dnp, uiop->uio_offset, 0);
2291 	if (cookiep) {
2292 		cookie = *cookiep;
2293 		ncl_dircookie_unlock(dnp);
2294 	} else {
2295 		ncl_dircookie_unlock(dnp);
2296 		return (NFSERR_BAD_COOKIE);
2297 	}
2298 
2299 	if (NFSHASNFSV3(nmp) && !NFSHASGOTFSINFO(nmp))
2300 		(void)ncl_fsinfo(nmp, vp, cred, td);
2301 
2302 	error = nfsrpc_readdir(vp, uiop, &cookie, cred, td, &nfsva,
2303 	    &attrflag, &eof, NULL);
2304 	if (attrflag)
2305 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
2306 
2307 	if (!error) {
2308 		/*
2309 		 * We are now either at the end of the directory or have filled
2310 		 * the block.
2311 		 */
2312 		if (eof)
2313 			dnp->n_direofoffset = uiop->uio_offset;
2314 		else {
2315 			if (uiop->uio_resid > 0)
2316 				ncl_printf("EEK! readdirrpc resid > 0\n");
2317 			ncl_dircookie_lock(dnp);
2318 			cookiep = ncl_getcookie(dnp, uiop->uio_offset, 1);
2319 			*cookiep = cookie;
2320 			ncl_dircookie_unlock(dnp);
2321 		}
2322 	} else if (NFS_ISV4(vp)) {
2323 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2324 	}
2325 	return (error);
2326 }
2327 
2328 /*
2329  * NFS V3 readdir plus RPC. Used in place of ncl_readdirrpc().
2330  */
2331 int
2332 ncl_readdirplusrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
2333     struct thread *td)
2334 {
2335 	struct nfsvattr nfsva;
2336 	nfsuint64 *cookiep, cookie;
2337 	struct nfsnode *dnp = VTONFS(vp);
2338 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2339 	int error = 0, attrflag, eof;
2340 
2341 	KASSERT(uiop->uio_iovcnt == 1 &&
2342 	    (uiop->uio_offset & (DIRBLKSIZ - 1)) == 0 &&
2343 	    (uiop->uio_resid & (DIRBLKSIZ - 1)) == 0,
2344 	    ("nfs readdirplusrpc bad uio"));
2345 
2346 	/*
2347 	 * If there is no cookie, assume directory was stale.
2348 	 */
2349 	ncl_dircookie_lock(dnp);
2350 	cookiep = ncl_getcookie(dnp, uiop->uio_offset, 0);
2351 	if (cookiep) {
2352 		cookie = *cookiep;
2353 		ncl_dircookie_unlock(dnp);
2354 	} else {
2355 		ncl_dircookie_unlock(dnp);
2356 		return (NFSERR_BAD_COOKIE);
2357 	}
2358 
2359 	if (NFSHASNFSV3(nmp) && !NFSHASGOTFSINFO(nmp))
2360 		(void)ncl_fsinfo(nmp, vp, cred, td);
2361 	error = nfsrpc_readdirplus(vp, uiop, &cookie, cred, td, &nfsva,
2362 	    &attrflag, &eof, NULL);
2363 	if (attrflag)
2364 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0, 1);
2365 
2366 	if (!error) {
2367 		/*
2368 		 * We are now either at end of the directory or have filled the
2369 		 * the block.
2370 		 */
2371 		if (eof)
2372 			dnp->n_direofoffset = uiop->uio_offset;
2373 		else {
2374 			if (uiop->uio_resid > 0)
2375 				ncl_printf("EEK! readdirplusrpc resid > 0\n");
2376 			ncl_dircookie_lock(dnp);
2377 			cookiep = ncl_getcookie(dnp, uiop->uio_offset, 1);
2378 			*cookiep = cookie;
2379 			ncl_dircookie_unlock(dnp);
2380 		}
2381 	} else if (NFS_ISV4(vp)) {
2382 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2383 	}
2384 	return (error);
2385 }
2386 
2387 /*
2388  * Silly rename. To make the NFS filesystem that is stateless look a little
2389  * more like the "ufs" a remove of an active vnode is translated to a rename
2390  * to a funny looking filename that is removed by nfs_inactive on the
2391  * nfsnode. There is the potential for another process on a different client
2392  * to create the same funny name between the nfs_lookitup() fails and the
2393  * nfs_rename() completes, but...
2394  */
2395 static int
2396 nfs_sillyrename(struct vnode *dvp, struct vnode *vp, struct componentname *cnp)
2397 {
2398 	struct sillyrename *sp;
2399 	struct nfsnode *np;
2400 	int error;
2401 	short pid;
2402 	unsigned int lticks;
2403 
2404 	cache_purge(dvp);
2405 	np = VTONFS(vp);
2406 	KASSERT(vp->v_type != VDIR, ("nfs: sillyrename dir"));
2407 	MALLOC(sp, struct sillyrename *, sizeof (struct sillyrename),
2408 	    M_NEWNFSREQ, M_WAITOK);
2409 	sp->s_cred = crhold(cnp->cn_cred);
2410 	sp->s_dvp = dvp;
2411 	VREF(dvp);
2412 
2413 	/*
2414 	 * Fudge together a funny name.
2415 	 * Changing the format of the funny name to accommodate more
2416 	 * sillynames per directory.
2417 	 * The name is now changed to .nfs.<ticks>.<pid>.4, where ticks is
2418 	 * CPU ticks since boot.
2419 	 */
2420 	pid = cnp->cn_thread->td_proc->p_pid;
2421 	lticks = (unsigned int)ticks;
2422 	for ( ; ; ) {
2423 		sp->s_namlen = sprintf(sp->s_name,
2424 				       ".nfs.%08x.%04x4.4", lticks,
2425 				       pid);
2426 		if (nfs_lookitup(dvp, sp->s_name, sp->s_namlen, sp->s_cred,
2427 				 cnp->cn_thread, NULL))
2428 			break;
2429 		lticks++;
2430 	}
2431 	error = nfs_renameit(dvp, vp, cnp, sp);
2432 	if (error)
2433 		goto bad;
2434 	error = nfs_lookitup(dvp, sp->s_name, sp->s_namlen, sp->s_cred,
2435 		cnp->cn_thread, &np);
2436 	np->n_sillyrename = sp;
2437 	return (0);
2438 bad:
2439 	vrele(sp->s_dvp);
2440 	crfree(sp->s_cred);
2441 	free((caddr_t)sp, M_NEWNFSREQ);
2442 	return (error);
2443 }
2444 
2445 /*
2446  * Look up a file name and optionally either update the file handle or
2447  * allocate an nfsnode, depending on the value of npp.
2448  * npp == NULL	--> just do the lookup
2449  * *npp == NULL --> allocate a new nfsnode and make sure attributes are
2450  *			handled too
2451  * *npp != NULL --> update the file handle in the vnode
2452  */
2453 static int
2454 nfs_lookitup(struct vnode *dvp, char *name, int len, struct ucred *cred,
2455     struct thread *td, struct nfsnode **npp)
2456 {
2457 	struct vnode *newvp = NULL, *vp;
2458 	struct nfsnode *np, *dnp = VTONFS(dvp);
2459 	struct nfsfh *nfhp, *onfhp;
2460 	struct nfsvattr nfsva, dnfsva;
2461 	struct componentname cn;
2462 	int error = 0, attrflag, dattrflag;
2463 	u_int hash;
2464 
2465 	error = nfsrpc_lookup(dvp, name, len, cred, td, &dnfsva, &nfsva,
2466 	    &nfhp, &attrflag, &dattrflag, NULL);
2467 	if (dattrflag)
2468 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, NULL, 0, 1);
2469 	if (npp && !error) {
2470 		if (*npp != NULL) {
2471 		    np = *npp;
2472 		    vp = NFSTOV(np);
2473 		    /*
2474 		     * For NFSv4, check to see if it is the same name and
2475 		     * replace the name, if it is different.
2476 		     */
2477 		    if (np->n_v4 != NULL && nfsva.na_type == VREG &&
2478 			(np->n_v4->n4_namelen != len ||
2479 			 NFSBCMP(name, NFS4NODENAME(np->n_v4), len) ||
2480 			 dnp->n_fhp->nfh_len != np->n_v4->n4_fhlen ||
2481 			 NFSBCMP(dnp->n_fhp->nfh_fh, np->n_v4->n4_data,
2482 			 dnp->n_fhp->nfh_len))) {
2483 #ifdef notdef
2484 { char nnn[100]; int nnnl;
2485 nnnl = (len < 100) ? len : 99;
2486 bcopy(name, nnn, nnnl);
2487 nnn[nnnl] = '\0';
2488 printf("replace=%s\n",nnn);
2489 }
2490 #endif
2491 			    FREE((caddr_t)np->n_v4, M_NFSV4NODE);
2492 			    MALLOC(np->n_v4, struct nfsv4node *,
2493 				sizeof (struct nfsv4node) +
2494 				dnp->n_fhp->nfh_len + len - 1,
2495 				M_NFSV4NODE, M_WAITOK);
2496 			    np->n_v4->n4_fhlen = dnp->n_fhp->nfh_len;
2497 			    np->n_v4->n4_namelen = len;
2498 			    NFSBCOPY(dnp->n_fhp->nfh_fh, np->n_v4->n4_data,
2499 				dnp->n_fhp->nfh_len);
2500 			    NFSBCOPY(name, NFS4NODENAME(np->n_v4), len);
2501 		    }
2502 		    hash = fnv_32_buf(nfhp->nfh_fh, nfhp->nfh_len,
2503 			FNV1_32_INIT);
2504 		    onfhp = np->n_fhp;
2505 		    /*
2506 		     * Rehash node for new file handle.
2507 		     */
2508 		    vfs_hash_rehash(vp, hash);
2509 		    np->n_fhp = nfhp;
2510 		    if (onfhp != NULL)
2511 			FREE((caddr_t)onfhp, M_NFSFH);
2512 		    newvp = NFSTOV(np);
2513 		} else if (NFS_CMPFH(dnp, nfhp->nfh_fh, nfhp->nfh_len)) {
2514 		    FREE((caddr_t)nfhp, M_NFSFH);
2515 		    VREF(dvp);
2516 		    newvp = dvp;
2517 		} else {
2518 		    cn.cn_nameptr = name;
2519 		    cn.cn_namelen = len;
2520 		    error = nfscl_nget(dvp->v_mount, dvp, nfhp, &cn, td,
2521 			&np, NULL, LK_EXCLUSIVE);
2522 		    if (error)
2523 			return (error);
2524 		    newvp = NFSTOV(np);
2525 		}
2526 		if (!attrflag && *npp == NULL) {
2527 			if (newvp == dvp)
2528 				vrele(newvp);
2529 			else
2530 				vput(newvp);
2531 			return (ENOENT);
2532 		}
2533 		if (attrflag)
2534 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, NULL,
2535 			    0, 1);
2536 	}
2537 	if (npp && *npp == NULL) {
2538 		if (error) {
2539 			if (newvp) {
2540 				if (newvp == dvp)
2541 					vrele(newvp);
2542 				else
2543 					vput(newvp);
2544 			}
2545 		} else
2546 			*npp = np;
2547 	}
2548 	if (error && NFS_ISV4(dvp))
2549 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2550 	return (error);
2551 }
2552 
2553 /*
2554  * Nfs Version 3 and 4 commit rpc
2555  */
2556 int
2557 ncl_commit(struct vnode *vp, u_quad_t offset, int cnt, struct ucred *cred,
2558    struct thread *td)
2559 {
2560 	struct nfsvattr nfsva;
2561 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2562 	int error, attrflag;
2563 
2564 	mtx_lock(&nmp->nm_mtx);
2565 	if ((nmp->nm_state & NFSSTA_HASWRITEVERF) == 0) {
2566 		mtx_unlock(&nmp->nm_mtx);
2567 		return (0);
2568 	}
2569 	mtx_unlock(&nmp->nm_mtx);
2570 	error = nfsrpc_commit(vp, offset, cnt, cred, td, &nfsva,
2571 	    &attrflag, NULL);
2572 	if (attrflag != 0)
2573 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL,
2574 		    0, 1);
2575 	if (error != 0 && NFS_ISV4(vp))
2576 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2577 	return (error);
2578 }
2579 
2580 /*
2581  * Strategy routine.
2582  * For async requests when nfsiod(s) are running, queue the request by
2583  * calling ncl_asyncio(), otherwise just all ncl_doio() to do the
2584  * request.
2585  */
2586 static int
2587 nfs_strategy(struct vop_strategy_args *ap)
2588 {
2589 	struct buf *bp = ap->a_bp;
2590 	struct ucred *cr;
2591 
2592 	KASSERT(!(bp->b_flags & B_DONE),
2593 	    ("nfs_strategy: buffer %p unexpectedly marked B_DONE", bp));
2594 	BUF_ASSERT_HELD(bp);
2595 
2596 	if (bp->b_iocmd == BIO_READ)
2597 		cr = bp->b_rcred;
2598 	else
2599 		cr = bp->b_wcred;
2600 
2601 	/*
2602 	 * If the op is asynchronous and an i/o daemon is waiting
2603 	 * queue the request, wake it up and wait for completion
2604 	 * otherwise just do it ourselves.
2605 	 */
2606 	if ((bp->b_flags & B_ASYNC) == 0 ||
2607 	    ncl_asyncio(VFSTONFS(ap->a_vp->v_mount), bp, NOCRED, curthread))
2608 		(void) ncl_doio(ap->a_vp, bp, cr, curthread, 1);
2609 	return (0);
2610 }
2611 
2612 /*
2613  * fsync vnode op. Just call ncl_flush() with commit == 1.
2614  */
2615 /* ARGSUSED */
2616 static int
2617 nfs_fsync(struct vop_fsync_args *ap)
2618 {
2619 
2620 	if (ap->a_vp->v_type != VREG) {
2621 		/*
2622 		 * For NFS, metadata is changed synchronously on the server,
2623 		 * so there is nothing to flush. Also, ncl_flush() clears
2624 		 * the NMODIFIED flag and that shouldn't be done here for
2625 		 * directories.
2626 		 */
2627 		return (0);
2628 	}
2629 	return (ncl_flush(ap->a_vp, ap->a_waitfor, NULL, ap->a_td, 1, 0));
2630 }
2631 
2632 /*
2633  * Flush all the blocks associated with a vnode.
2634  * 	Walk through the buffer pool and push any dirty pages
2635  *	associated with the vnode.
2636  * If the called_from_renewthread argument is TRUE, it has been called
2637  * from the NFSv4 renew thread and, as such, cannot block indefinitely
2638  * waiting for a buffer write to complete.
2639  */
2640 int
2641 ncl_flush(struct vnode *vp, int waitfor, struct ucred *cred, struct thread *td,
2642     int commit, int called_from_renewthread)
2643 {
2644 	struct nfsnode *np = VTONFS(vp);
2645 	struct buf *bp;
2646 	int i;
2647 	struct buf *nbp;
2648 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2649 	int error = 0, slptimeo = 0, slpflag = 0, retv, bvecpos;
2650 	int passone = 1, trycnt = 0;
2651 	u_quad_t off, endoff, toff;
2652 	struct ucred* wcred = NULL;
2653 	struct buf **bvec = NULL;
2654 	struct bufobj *bo;
2655 #ifndef NFS_COMMITBVECSIZ
2656 #define	NFS_COMMITBVECSIZ	20
2657 #endif
2658 	struct buf *bvec_on_stack[NFS_COMMITBVECSIZ];
2659 	int bvecsize = 0, bveccount;
2660 
2661 	if (called_from_renewthread != 0)
2662 		slptimeo = hz;
2663 	if (nmp->nm_flag & NFSMNT_INT)
2664 		slpflag = PCATCH;
2665 	if (!commit)
2666 		passone = 0;
2667 	bo = &vp->v_bufobj;
2668 	/*
2669 	 * A b_flags == (B_DELWRI | B_NEEDCOMMIT) block has been written to the
2670 	 * server, but has not been committed to stable storage on the server
2671 	 * yet. On the first pass, the byte range is worked out and the commit
2672 	 * rpc is done. On the second pass, ncl_writebp() is called to do the
2673 	 * job.
2674 	 */
2675 again:
2676 	off = (u_quad_t)-1;
2677 	endoff = 0;
2678 	bvecpos = 0;
2679 	if (NFS_ISV34(vp) && commit) {
2680 		if (bvec != NULL && bvec != bvec_on_stack)
2681 			free(bvec, M_TEMP);
2682 		/*
2683 		 * Count up how many buffers waiting for a commit.
2684 		 */
2685 		bveccount = 0;
2686 		BO_LOCK(bo);
2687 		TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2688 			if (!BUF_ISLOCKED(bp) &&
2689 			    (bp->b_flags & (B_DELWRI | B_NEEDCOMMIT))
2690 				== (B_DELWRI | B_NEEDCOMMIT))
2691 				bveccount++;
2692 		}
2693 		/*
2694 		 * Allocate space to remember the list of bufs to commit.  It is
2695 		 * important to use M_NOWAIT here to avoid a race with nfs_write.
2696 		 * If we can't get memory (for whatever reason), we will end up
2697 		 * committing the buffers one-by-one in the loop below.
2698 		 */
2699 		if (bveccount > NFS_COMMITBVECSIZ) {
2700 			/*
2701 			 * Release the vnode interlock to avoid a lock
2702 			 * order reversal.
2703 			 */
2704 			BO_UNLOCK(bo);
2705 			bvec = (struct buf **)
2706 				malloc(bveccount * sizeof(struct buf *),
2707 				       M_TEMP, M_NOWAIT);
2708 			BO_LOCK(bo);
2709 			if (bvec == NULL) {
2710 				bvec = bvec_on_stack;
2711 				bvecsize = NFS_COMMITBVECSIZ;
2712 			} else
2713 				bvecsize = bveccount;
2714 		} else {
2715 			bvec = bvec_on_stack;
2716 			bvecsize = NFS_COMMITBVECSIZ;
2717 		}
2718 		TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2719 			if (bvecpos >= bvecsize)
2720 				break;
2721 			if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
2722 				nbp = TAILQ_NEXT(bp, b_bobufs);
2723 				continue;
2724 			}
2725 			if ((bp->b_flags & (B_DELWRI | B_NEEDCOMMIT)) !=
2726 			    (B_DELWRI | B_NEEDCOMMIT)) {
2727 				BUF_UNLOCK(bp);
2728 				nbp = TAILQ_NEXT(bp, b_bobufs);
2729 				continue;
2730 			}
2731 			BO_UNLOCK(bo);
2732 			bremfree(bp);
2733 			/*
2734 			 * Work out if all buffers are using the same cred
2735 			 * so we can deal with them all with one commit.
2736 			 *
2737 			 * NOTE: we are not clearing B_DONE here, so we have
2738 			 * to do it later on in this routine if we intend to
2739 			 * initiate I/O on the bp.
2740 			 *
2741 			 * Note: to avoid loopback deadlocks, we do not
2742 			 * assign b_runningbufspace.
2743 			 */
2744 			if (wcred == NULL)
2745 				wcred = bp->b_wcred;
2746 			else if (wcred != bp->b_wcred)
2747 				wcred = NOCRED;
2748 			vfs_busy_pages(bp, 1);
2749 
2750 			BO_LOCK(bo);
2751 			/*
2752 			 * bp is protected by being locked, but nbp is not
2753 			 * and vfs_busy_pages() may sleep.  We have to
2754 			 * recalculate nbp.
2755 			 */
2756 			nbp = TAILQ_NEXT(bp, b_bobufs);
2757 
2758 			/*
2759 			 * A list of these buffers is kept so that the
2760 			 * second loop knows which buffers have actually
2761 			 * been committed. This is necessary, since there
2762 			 * may be a race between the commit rpc and new
2763 			 * uncommitted writes on the file.
2764 			 */
2765 			bvec[bvecpos++] = bp;
2766 			toff = ((u_quad_t)bp->b_blkno) * DEV_BSIZE +
2767 				bp->b_dirtyoff;
2768 			if (toff < off)
2769 				off = toff;
2770 			toff += (u_quad_t)(bp->b_dirtyend - bp->b_dirtyoff);
2771 			if (toff > endoff)
2772 				endoff = toff;
2773 		}
2774 		BO_UNLOCK(bo);
2775 	}
2776 	if (bvecpos > 0) {
2777 		/*
2778 		 * Commit data on the server, as required.
2779 		 * If all bufs are using the same wcred, then use that with
2780 		 * one call for all of them, otherwise commit each one
2781 		 * separately.
2782 		 */
2783 		if (wcred != NOCRED)
2784 			retv = ncl_commit(vp, off, (int)(endoff - off),
2785 					  wcred, td);
2786 		else {
2787 			retv = 0;
2788 			for (i = 0; i < bvecpos; i++) {
2789 				off_t off, size;
2790 				bp = bvec[i];
2791 				off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE +
2792 					bp->b_dirtyoff;
2793 				size = (u_quad_t)(bp->b_dirtyend
2794 						  - bp->b_dirtyoff);
2795 				retv = ncl_commit(vp, off, (int)size,
2796 						  bp->b_wcred, td);
2797 				if (retv) break;
2798 			}
2799 		}
2800 
2801 		if (retv == NFSERR_STALEWRITEVERF)
2802 			ncl_clearcommit(vp->v_mount);
2803 
2804 		/*
2805 		 * Now, either mark the blocks I/O done or mark the
2806 		 * blocks dirty, depending on whether the commit
2807 		 * succeeded.
2808 		 */
2809 		for (i = 0; i < bvecpos; i++) {
2810 			bp = bvec[i];
2811 			bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
2812 			if (retv) {
2813 				/*
2814 				 * Error, leave B_DELWRI intact
2815 				 */
2816 				vfs_unbusy_pages(bp);
2817 				brelse(bp);
2818 			} else {
2819 				/*
2820 				 * Success, remove B_DELWRI ( bundirty() ).
2821 				 *
2822 				 * b_dirtyoff/b_dirtyend seem to be NFS
2823 				 * specific.  We should probably move that
2824 				 * into bundirty(). XXX
2825 				 */
2826 				bufobj_wref(bo);
2827 				bp->b_flags |= B_ASYNC;
2828 				bundirty(bp);
2829 				bp->b_flags &= ~B_DONE;
2830 				bp->b_ioflags &= ~BIO_ERROR;
2831 				bp->b_dirtyoff = bp->b_dirtyend = 0;
2832 				bufdone(bp);
2833 			}
2834 		}
2835 	}
2836 
2837 	/*
2838 	 * Start/do any write(s) that are required.
2839 	 */
2840 loop:
2841 	BO_LOCK(bo);
2842 	TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2843 		if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
2844 			if (waitfor != MNT_WAIT || passone)
2845 				continue;
2846 
2847 			error = BUF_TIMELOCK(bp,
2848 			    LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
2849 			    BO_LOCKPTR(bo), "nfsfsync", slpflag, slptimeo);
2850 			if (error == 0) {
2851 				BUF_UNLOCK(bp);
2852 				goto loop;
2853 			}
2854 			if (error == ENOLCK) {
2855 				error = 0;
2856 				goto loop;
2857 			}
2858 			if (called_from_renewthread != 0) {
2859 				/*
2860 				 * Return EIO so the flush will be retried
2861 				 * later.
2862 				 */
2863 				error = EIO;
2864 				goto done;
2865 			}
2866 			if (newnfs_sigintr(nmp, td)) {
2867 				error = EINTR;
2868 				goto done;
2869 			}
2870 			if (slpflag == PCATCH) {
2871 				slpflag = 0;
2872 				slptimeo = 2 * hz;
2873 			}
2874 			goto loop;
2875 		}
2876 		if ((bp->b_flags & B_DELWRI) == 0)
2877 			panic("nfs_fsync: not dirty");
2878 		if ((passone || !commit) && (bp->b_flags & B_NEEDCOMMIT)) {
2879 			BUF_UNLOCK(bp);
2880 			continue;
2881 		}
2882 		BO_UNLOCK(bo);
2883 		bremfree(bp);
2884 		if (passone || !commit)
2885 		    bp->b_flags |= B_ASYNC;
2886 		else
2887 		    bp->b_flags |= B_ASYNC;
2888 		bwrite(bp);
2889 		if (newnfs_sigintr(nmp, td)) {
2890 			error = EINTR;
2891 			goto done;
2892 		}
2893 		goto loop;
2894 	}
2895 	if (passone) {
2896 		passone = 0;
2897 		BO_UNLOCK(bo);
2898 		goto again;
2899 	}
2900 	if (waitfor == MNT_WAIT) {
2901 		while (bo->bo_numoutput) {
2902 			error = bufobj_wwait(bo, slpflag, slptimeo);
2903 			if (error) {
2904 			    BO_UNLOCK(bo);
2905 			    if (called_from_renewthread != 0) {
2906 				/*
2907 				 * Return EIO so that the flush will be
2908 				 * retried later.
2909 				 */
2910 				error = EIO;
2911 				goto done;
2912 			    }
2913 			    error = newnfs_sigintr(nmp, td);
2914 			    if (error)
2915 				goto done;
2916 			    if (slpflag == PCATCH) {
2917 				slpflag = 0;
2918 				slptimeo = 2 * hz;
2919 			    }
2920 			    BO_LOCK(bo);
2921 			}
2922 		}
2923 		if (bo->bo_dirty.bv_cnt != 0 && commit) {
2924 			BO_UNLOCK(bo);
2925 			goto loop;
2926 		}
2927 		/*
2928 		 * Wait for all the async IO requests to drain
2929 		 */
2930 		BO_UNLOCK(bo);
2931 		mtx_lock(&np->n_mtx);
2932 		while (np->n_directio_asyncwr > 0) {
2933 			np->n_flag |= NFSYNCWAIT;
2934 			error = newnfs_msleep(td, &np->n_directio_asyncwr,
2935 			    &np->n_mtx, slpflag | (PRIBIO + 1),
2936 			    "nfsfsync", 0);
2937 			if (error) {
2938 				if (newnfs_sigintr(nmp, td)) {
2939 					mtx_unlock(&np->n_mtx);
2940 					error = EINTR;
2941 					goto done;
2942 				}
2943 			}
2944 		}
2945 		mtx_unlock(&np->n_mtx);
2946 	} else
2947 		BO_UNLOCK(bo);
2948 	if (NFSHASPNFS(nmp)) {
2949 		nfscl_layoutcommit(vp, td);
2950 		/*
2951 		 * Invalidate the attribute cache, since writes to a DS
2952 		 * won't update the size attribute.
2953 		 */
2954 		mtx_lock(&np->n_mtx);
2955 		np->n_attrstamp = 0;
2956 	} else
2957 		mtx_lock(&np->n_mtx);
2958 	if (np->n_flag & NWRITEERR) {
2959 		error = np->n_error;
2960 		np->n_flag &= ~NWRITEERR;
2961 	}
2962   	if (commit && bo->bo_dirty.bv_cnt == 0 &&
2963 	    bo->bo_numoutput == 0 && np->n_directio_asyncwr == 0)
2964   		np->n_flag &= ~NMODIFIED;
2965 	mtx_unlock(&np->n_mtx);
2966 done:
2967 	if (bvec != NULL && bvec != bvec_on_stack)
2968 		free(bvec, M_TEMP);
2969 	if (error == 0 && commit != 0 && waitfor == MNT_WAIT &&
2970 	    (bo->bo_dirty.bv_cnt != 0 || bo->bo_numoutput != 0 ||
2971 	     np->n_directio_asyncwr != 0) && trycnt++ < 5) {
2972 		/* try, try again... */
2973 		passone = 1;
2974 		wcred = NULL;
2975 		bvec = NULL;
2976 		bvecsize = 0;
2977 printf("try%d\n", trycnt);
2978 		goto again;
2979 	}
2980 	return (error);
2981 }
2982 
2983 /*
2984  * NFS advisory byte-level locks.
2985  */
2986 static int
2987 nfs_advlock(struct vop_advlock_args *ap)
2988 {
2989 	struct vnode *vp = ap->a_vp;
2990 	struct ucred *cred;
2991 	struct nfsnode *np = VTONFS(ap->a_vp);
2992 	struct proc *p = (struct proc *)ap->a_id;
2993 	struct thread *td = curthread;	/* XXX */
2994 	struct vattr va;
2995 	int ret, error = EOPNOTSUPP;
2996 	u_quad_t size;
2997 
2998 	if (NFS_ISV4(vp) && (ap->a_flags & (F_POSIX | F_FLOCK)) != 0) {
2999 		if (vp->v_type != VREG)
3000 			return (EINVAL);
3001 		if ((ap->a_flags & F_POSIX) != 0)
3002 			cred = p->p_ucred;
3003 		else
3004 			cred = td->td_ucred;
3005 		NFSVOPLOCK(vp, LK_EXCLUSIVE | LK_RETRY);
3006 		if (vp->v_iflag & VI_DOOMED) {
3007 			NFSVOPUNLOCK(vp, 0);
3008 			return (EBADF);
3009 		}
3010 
3011 		/*
3012 		 * If this is unlocking a write locked region, flush and
3013 		 * commit them before unlocking. This is required by
3014 		 * RFC3530 Sec. 9.3.2.
3015 		 */
3016 		if (ap->a_op == F_UNLCK &&
3017 		    nfscl_checkwritelocked(vp, ap->a_fl, cred, td, ap->a_id,
3018 		    ap->a_flags))
3019 			(void) ncl_flush(vp, MNT_WAIT, cred, td, 1, 0);
3020 
3021 		/*
3022 		 * Loop around doing the lock op, while a blocking lock
3023 		 * must wait for the lock op to succeed.
3024 		 */
3025 		do {
3026 			ret = nfsrpc_advlock(vp, np->n_size, ap->a_op,
3027 			    ap->a_fl, 0, cred, td, ap->a_id, ap->a_flags);
3028 			if (ret == NFSERR_DENIED && (ap->a_flags & F_WAIT) &&
3029 			    ap->a_op == F_SETLK) {
3030 				NFSVOPUNLOCK(vp, 0);
3031 				error = nfs_catnap(PZERO | PCATCH, ret,
3032 				    "ncladvl");
3033 				if (error)
3034 					return (EINTR);
3035 				NFSVOPLOCK(vp, LK_EXCLUSIVE | LK_RETRY);
3036 				if (vp->v_iflag & VI_DOOMED) {
3037 					NFSVOPUNLOCK(vp, 0);
3038 					return (EBADF);
3039 				}
3040 			}
3041 		} while (ret == NFSERR_DENIED && (ap->a_flags & F_WAIT) &&
3042 		     ap->a_op == F_SETLK);
3043 		if (ret == NFSERR_DENIED) {
3044 			NFSVOPUNLOCK(vp, 0);
3045 			return (EAGAIN);
3046 		} else if (ret == EINVAL || ret == EBADF || ret == EINTR) {
3047 			NFSVOPUNLOCK(vp, 0);
3048 			return (ret);
3049 		} else if (ret != 0) {
3050 			NFSVOPUNLOCK(vp, 0);
3051 			return (EACCES);
3052 		}
3053 
3054 		/*
3055 		 * Now, if we just got a lock, invalidate data in the buffer
3056 		 * cache, as required, so that the coherency conforms with
3057 		 * RFC3530 Sec. 9.3.2.
3058 		 */
3059 		if (ap->a_op == F_SETLK) {
3060 			if ((np->n_flag & NMODIFIED) == 0) {
3061 				np->n_attrstamp = 0;
3062 				KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
3063 				ret = VOP_GETATTR(vp, &va, cred);
3064 			}
3065 			if ((np->n_flag & NMODIFIED) || ret ||
3066 			    np->n_change != va.va_filerev) {
3067 				(void) ncl_vinvalbuf(vp, V_SAVE, td, 1);
3068 				np->n_attrstamp = 0;
3069 				KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
3070 				ret = VOP_GETATTR(vp, &va, cred);
3071 				if (!ret) {
3072 					np->n_mtime = va.va_mtime;
3073 					np->n_change = va.va_filerev;
3074 				}
3075 			}
3076 			/* Mark that a file lock has been acquired. */
3077 			mtx_lock(&np->n_mtx);
3078 			np->n_flag |= NHASBEENLOCKED;
3079 			mtx_unlock(&np->n_mtx);
3080 		}
3081 		NFSVOPUNLOCK(vp, 0);
3082 		return (0);
3083 	} else if (!NFS_ISV4(vp)) {
3084 		error = NFSVOPLOCK(vp, LK_SHARED);
3085 		if (error)
3086 			return (error);
3087 		if ((VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NOLOCKD) != 0) {
3088 			size = VTONFS(vp)->n_size;
3089 			NFSVOPUNLOCK(vp, 0);
3090 			error = lf_advlock(ap, &(vp->v_lockf), size);
3091 		} else {
3092 			if (nfs_advlock_p != NULL)
3093 				error = nfs_advlock_p(ap);
3094 			else {
3095 				NFSVOPUNLOCK(vp, 0);
3096 				error = ENOLCK;
3097 			}
3098 		}
3099 		if (error == 0 && ap->a_op == F_SETLK) {
3100 			/* Mark that a file lock has been acquired. */
3101 			mtx_lock(&np->n_mtx);
3102 			np->n_flag |= NHASBEENLOCKED;
3103 			mtx_unlock(&np->n_mtx);
3104 		}
3105 	}
3106 	return (error);
3107 }
3108 
3109 /*
3110  * NFS advisory byte-level locks.
3111  */
3112 static int
3113 nfs_advlockasync(struct vop_advlockasync_args *ap)
3114 {
3115 	struct vnode *vp = ap->a_vp;
3116 	u_quad_t size;
3117 	int error;
3118 
3119 	if (NFS_ISV4(vp))
3120 		return (EOPNOTSUPP);
3121 	error = NFSVOPLOCK(vp, LK_SHARED);
3122 	if (error)
3123 		return (error);
3124 	if ((VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NOLOCKD) != 0) {
3125 		size = VTONFS(vp)->n_size;
3126 		NFSVOPUNLOCK(vp, 0);
3127 		error = lf_advlockasync(ap, &(vp->v_lockf), size);
3128 	} else {
3129 		NFSVOPUNLOCK(vp, 0);
3130 		error = EOPNOTSUPP;
3131 	}
3132 	return (error);
3133 }
3134 
3135 /*
3136  * Print out the contents of an nfsnode.
3137  */
3138 static int
3139 nfs_print(struct vop_print_args *ap)
3140 {
3141 	struct vnode *vp = ap->a_vp;
3142 	struct nfsnode *np = VTONFS(vp);
3143 
3144 	ncl_printf("\tfileid %ld fsid 0x%x",
3145 	   np->n_vattr.na_fileid, np->n_vattr.na_fsid);
3146 	if (vp->v_type == VFIFO)
3147 		fifo_printinfo(vp);
3148 	printf("\n");
3149 	return (0);
3150 }
3151 
3152 /*
3153  * This is the "real" nfs::bwrite(struct buf*).
3154  * We set B_CACHE if this is a VMIO buffer.
3155  */
3156 int
3157 ncl_writebp(struct buf *bp, int force __unused, struct thread *td)
3158 {
3159 	int s;
3160 	int oldflags = bp->b_flags;
3161 #if 0
3162 	int retv = 1;
3163 	off_t off;
3164 #endif
3165 
3166 	BUF_ASSERT_HELD(bp);
3167 
3168 	if (bp->b_flags & B_INVAL) {
3169 		brelse(bp);
3170 		return(0);
3171 	}
3172 
3173 	bp->b_flags |= B_CACHE;
3174 
3175 	/*
3176 	 * Undirty the bp.  We will redirty it later if the I/O fails.
3177 	 */
3178 
3179 	s = splbio();
3180 	bundirty(bp);
3181 	bp->b_flags &= ~B_DONE;
3182 	bp->b_ioflags &= ~BIO_ERROR;
3183 	bp->b_iocmd = BIO_WRITE;
3184 
3185 	bufobj_wref(bp->b_bufobj);
3186 	curthread->td_ru.ru_oublock++;
3187 	splx(s);
3188 
3189 	/*
3190 	 * Note: to avoid loopback deadlocks, we do not
3191 	 * assign b_runningbufspace.
3192 	 */
3193 	vfs_busy_pages(bp, 1);
3194 
3195 	BUF_KERNPROC(bp);
3196 	bp->b_iooffset = dbtob(bp->b_blkno);
3197 	bstrategy(bp);
3198 
3199 	if( (oldflags & B_ASYNC) == 0) {
3200 		int rtval = bufwait(bp);
3201 
3202 		if (oldflags & B_DELWRI) {
3203 			s = splbio();
3204 			reassignbuf(bp);
3205 			splx(s);
3206 		}
3207 		brelse(bp);
3208 		return (rtval);
3209 	}
3210 
3211 	return (0);
3212 }
3213 
3214 /*
3215  * nfs special file access vnode op.
3216  * Essentially just get vattr and then imitate iaccess() since the device is
3217  * local to the client.
3218  */
3219 static int
3220 nfsspec_access(struct vop_access_args *ap)
3221 {
3222 	struct vattr *vap;
3223 	struct ucred *cred = ap->a_cred;
3224 	struct vnode *vp = ap->a_vp;
3225 	accmode_t accmode = ap->a_accmode;
3226 	struct vattr vattr;
3227 	int error;
3228 
3229 	/*
3230 	 * Disallow write attempts on filesystems mounted read-only;
3231 	 * unless the file is a socket, fifo, or a block or character
3232 	 * device resident on the filesystem.
3233 	 */
3234 	if ((accmode & VWRITE) && (vp->v_mount->mnt_flag & MNT_RDONLY)) {
3235 		switch (vp->v_type) {
3236 		case VREG:
3237 		case VDIR:
3238 		case VLNK:
3239 			return (EROFS);
3240 		default:
3241 			break;
3242 		}
3243 	}
3244 	vap = &vattr;
3245 	error = VOP_GETATTR(vp, vap, cred);
3246 	if (error)
3247 		goto out;
3248 	error  = vaccess(vp->v_type, vap->va_mode, vap->va_uid, vap->va_gid,
3249 	    accmode, cred, NULL);
3250 out:
3251 	return error;
3252 }
3253 
3254 /*
3255  * Read wrapper for fifos.
3256  */
3257 static int
3258 nfsfifo_read(struct vop_read_args *ap)
3259 {
3260 	struct nfsnode *np = VTONFS(ap->a_vp);
3261 	int error;
3262 
3263 	/*
3264 	 * Set access flag.
3265 	 */
3266 	mtx_lock(&np->n_mtx);
3267 	np->n_flag |= NACC;
3268 	vfs_timestamp(&np->n_atim);
3269 	mtx_unlock(&np->n_mtx);
3270 	error = fifo_specops.vop_read(ap);
3271 	return error;
3272 }
3273 
3274 /*
3275  * Write wrapper for fifos.
3276  */
3277 static int
3278 nfsfifo_write(struct vop_write_args *ap)
3279 {
3280 	struct nfsnode *np = VTONFS(ap->a_vp);
3281 
3282 	/*
3283 	 * Set update flag.
3284 	 */
3285 	mtx_lock(&np->n_mtx);
3286 	np->n_flag |= NUPD;
3287 	vfs_timestamp(&np->n_mtim);
3288 	mtx_unlock(&np->n_mtx);
3289 	return(fifo_specops.vop_write(ap));
3290 }
3291 
3292 /*
3293  * Close wrapper for fifos.
3294  *
3295  * Update the times on the nfsnode then do fifo close.
3296  */
3297 static int
3298 nfsfifo_close(struct vop_close_args *ap)
3299 {
3300 	struct vnode *vp = ap->a_vp;
3301 	struct nfsnode *np = VTONFS(vp);
3302 	struct vattr vattr;
3303 	struct timespec ts;
3304 
3305 	mtx_lock(&np->n_mtx);
3306 	if (np->n_flag & (NACC | NUPD)) {
3307 		vfs_timestamp(&ts);
3308 		if (np->n_flag & NACC)
3309 			np->n_atim = ts;
3310 		if (np->n_flag & NUPD)
3311 			np->n_mtim = ts;
3312 		np->n_flag |= NCHG;
3313 		if (vrefcnt(vp) == 1 &&
3314 		    (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
3315 			VATTR_NULL(&vattr);
3316 			if (np->n_flag & NACC)
3317 				vattr.va_atime = np->n_atim;
3318 			if (np->n_flag & NUPD)
3319 				vattr.va_mtime = np->n_mtim;
3320 			mtx_unlock(&np->n_mtx);
3321 			(void)VOP_SETATTR(vp, &vattr, ap->a_cred);
3322 			goto out;
3323 		}
3324 	}
3325 	mtx_unlock(&np->n_mtx);
3326 out:
3327 	return (fifo_specops.vop_close(ap));
3328 }
3329 
3330 /*
3331  * Just call ncl_writebp() with the force argument set to 1.
3332  *
3333  * NOTE: B_DONE may or may not be set in a_bp on call.
3334  */
3335 static int
3336 nfs_bwrite(struct buf *bp)
3337 {
3338 
3339 	return (ncl_writebp(bp, 1, curthread));
3340 }
3341 
3342 struct buf_ops buf_ops_newnfs = {
3343 	.bop_name	=	"buf_ops_nfs",
3344 	.bop_write	=	nfs_bwrite,
3345 	.bop_strategy	=	bufstrategy,
3346 	.bop_sync	=	bufsync,
3347 	.bop_bdflush	=	bufbdflush,
3348 };
3349 
3350 static int
3351 nfs_getacl(struct vop_getacl_args *ap)
3352 {
3353 	int error;
3354 
3355 	if (ap->a_type != ACL_TYPE_NFS4)
3356 		return (EOPNOTSUPP);
3357 	error = nfsrpc_getacl(ap->a_vp, ap->a_cred, ap->a_td, ap->a_aclp,
3358 	    NULL);
3359 	if (error > NFSERR_STALE) {
3360 		(void) nfscl_maperr(ap->a_td, error, (uid_t)0, (gid_t)0);
3361 		error = EPERM;
3362 	}
3363 	return (error);
3364 }
3365 
3366 static int
3367 nfs_setacl(struct vop_setacl_args *ap)
3368 {
3369 	int error;
3370 
3371 	if (ap->a_type != ACL_TYPE_NFS4)
3372 		return (EOPNOTSUPP);
3373 	error = nfsrpc_setacl(ap->a_vp, ap->a_cred, ap->a_td, ap->a_aclp,
3374 	    NULL);
3375 	if (error > NFSERR_STALE) {
3376 		(void) nfscl_maperr(ap->a_td, error, (uid_t)0, (gid_t)0);
3377 		error = EPERM;
3378 	}
3379 	return (error);
3380 }
3381 
3382 /*
3383  * Return POSIX pathconf information applicable to nfs filesystems.
3384  */
3385 static int
3386 nfs_pathconf(struct vop_pathconf_args *ap)
3387 {
3388 	struct nfsv3_pathconf pc;
3389 	struct nfsvattr nfsva;
3390 	struct vnode *vp = ap->a_vp;
3391 	struct thread *td = curthread;
3392 	int attrflag, error;
3393 
3394 	if ((NFS_ISV34(vp) && (ap->a_name == _PC_LINK_MAX ||
3395 	    ap->a_name == _PC_NAME_MAX || ap->a_name == _PC_CHOWN_RESTRICTED ||
3396 	    ap->a_name == _PC_NO_TRUNC)) ||
3397 	    (NFS_ISV4(vp) && ap->a_name == _PC_ACL_NFS4)) {
3398 		/*
3399 		 * Since only the above 4 a_names are returned by the NFSv3
3400 		 * Pathconf RPC, there is no point in doing it for others.
3401 		 * For NFSv4, the Pathconf RPC (actually a Getattr Op.) can
3402 		 * be used for _PC_NFS4_ACL as well.
3403 		 */
3404 		error = nfsrpc_pathconf(vp, &pc, td->td_ucred, td, &nfsva,
3405 		    &attrflag, NULL);
3406 		if (attrflag != 0)
3407 			(void) nfscl_loadattrcache(&vp, &nfsva, NULL, NULL, 0,
3408 			    1);
3409 		if (error != 0)
3410 			return (error);
3411 	} else {
3412 		/*
3413 		 * For NFSv2 (or NFSv3 when not one of the above 4 a_names),
3414 		 * just fake them.
3415 		 */
3416 		pc.pc_linkmax = LINK_MAX;
3417 		pc.pc_namemax = NFS_MAXNAMLEN;
3418 		pc.pc_notrunc = 1;
3419 		pc.pc_chownrestricted = 1;
3420 		pc.pc_caseinsensitive = 0;
3421 		pc.pc_casepreserving = 1;
3422 		error = 0;
3423 	}
3424 	switch (ap->a_name) {
3425 	case _PC_LINK_MAX:
3426 		*ap->a_retval = pc.pc_linkmax;
3427 		break;
3428 	case _PC_NAME_MAX:
3429 		*ap->a_retval = pc.pc_namemax;
3430 		break;
3431 	case _PC_PATH_MAX:
3432 		*ap->a_retval = PATH_MAX;
3433 		break;
3434 	case _PC_PIPE_BUF:
3435 		*ap->a_retval = PIPE_BUF;
3436 		break;
3437 	case _PC_CHOWN_RESTRICTED:
3438 		*ap->a_retval = pc.pc_chownrestricted;
3439 		break;
3440 	case _PC_NO_TRUNC:
3441 		*ap->a_retval = pc.pc_notrunc;
3442 		break;
3443 	case _PC_ACL_EXTENDED:
3444 		*ap->a_retval = 0;
3445 		break;
3446 	case _PC_ACL_NFS4:
3447 		if (NFS_ISV4(vp) && nfsrv_useacl != 0 && attrflag != 0 &&
3448 		    NFSISSET_ATTRBIT(&nfsva.na_suppattr, NFSATTRBIT_ACL))
3449 			*ap->a_retval = 1;
3450 		else
3451 			*ap->a_retval = 0;
3452 		break;
3453 	case _PC_ACL_PATH_MAX:
3454 		if (NFS_ISV4(vp))
3455 			*ap->a_retval = ACL_MAX_ENTRIES;
3456 		else
3457 			*ap->a_retval = 3;
3458 		break;
3459 	case _PC_MAC_PRESENT:
3460 		*ap->a_retval = 0;
3461 		break;
3462 	case _PC_ASYNC_IO:
3463 		/* _PC_ASYNC_IO should have been handled by upper layers. */
3464 		KASSERT(0, ("_PC_ASYNC_IO should not get here"));
3465 		error = EINVAL;
3466 		break;
3467 	case _PC_PRIO_IO:
3468 		*ap->a_retval = 0;
3469 		break;
3470 	case _PC_SYNC_IO:
3471 		*ap->a_retval = 0;
3472 		break;
3473 	case _PC_ALLOC_SIZE_MIN:
3474 		*ap->a_retval = vp->v_mount->mnt_stat.f_bsize;
3475 		break;
3476 	case _PC_FILESIZEBITS:
3477 		if (NFS_ISV34(vp))
3478 			*ap->a_retval = 64;
3479 		else
3480 			*ap->a_retval = 32;
3481 		break;
3482 	case _PC_REC_INCR_XFER_SIZE:
3483 		*ap->a_retval = vp->v_mount->mnt_stat.f_iosize;
3484 		break;
3485 	case _PC_REC_MAX_XFER_SIZE:
3486 		*ap->a_retval = -1; /* means ``unlimited'' */
3487 		break;
3488 	case _PC_REC_MIN_XFER_SIZE:
3489 		*ap->a_retval = vp->v_mount->mnt_stat.f_iosize;
3490 		break;
3491 	case _PC_REC_XFER_ALIGN:
3492 		*ap->a_retval = PAGE_SIZE;
3493 		break;
3494 	case _PC_SYMLINK_MAX:
3495 		*ap->a_retval = NFS_MAXPATHLEN;
3496 		break;
3497 
3498 	default:
3499 		error = EINVAL;
3500 		break;
3501 	}
3502 	return (error);
3503 }
3504 
3505