xref: /freebsd/sys/fs/nfsclient/nfs_clvnops.c (revision 1f1e2261)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Rick Macklem at The University of Guelph.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	from nfs_vnops.c	8.16 (Berkeley) 5/27/95
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 /*
41  * vnode op calls for Sun NFS version 2, 3 and 4
42  */
43 
44 #include "opt_inet.h"
45 
46 #include <sys/param.h>
47 #include <sys/kernel.h>
48 #include <sys/systm.h>
49 #include <sys/resourcevar.h>
50 #include <sys/proc.h>
51 #include <sys/mount.h>
52 #include <sys/bio.h>
53 #include <sys/buf.h>
54 #include <sys/extattr.h>
55 #include <sys/filio.h>
56 #include <sys/jail.h>
57 #include <sys/malloc.h>
58 #include <sys/mbuf.h>
59 #include <sys/namei.h>
60 #include <sys/socket.h>
61 #include <sys/vnode.h>
62 #include <sys/dirent.h>
63 #include <sys/fcntl.h>
64 #include <sys/lockf.h>
65 #include <sys/stat.h>
66 #include <sys/sysctl.h>
67 #include <sys/signalvar.h>
68 
69 #include <vm/vm.h>
70 #include <vm/vm_extern.h>
71 #include <vm/vm_object.h>
72 
73 #include <fs/nfs/nfsport.h>
74 #include <fs/nfsclient/nfsnode.h>
75 #include <fs/nfsclient/nfsmount.h>
76 #include <fs/nfsclient/nfs.h>
77 #include <fs/nfsclient/nfs_kdtrace.h>
78 
79 #include <net/if.h>
80 #include <netinet/in.h>
81 #include <netinet/in_var.h>
82 
83 #include <nfs/nfs_lock.h>
84 
85 #ifdef KDTRACE_HOOKS
86 #include <sys/dtrace_bsd.h>
87 
88 dtrace_nfsclient_accesscache_flush_probe_func_t
89 		dtrace_nfscl_accesscache_flush_done_probe;
90 uint32_t	nfscl_accesscache_flush_done_id;
91 
92 dtrace_nfsclient_accesscache_get_probe_func_t
93 		dtrace_nfscl_accesscache_get_hit_probe,
94 		dtrace_nfscl_accesscache_get_miss_probe;
95 uint32_t	nfscl_accesscache_get_hit_id;
96 uint32_t	nfscl_accesscache_get_miss_id;
97 
98 dtrace_nfsclient_accesscache_load_probe_func_t
99 		dtrace_nfscl_accesscache_load_done_probe;
100 uint32_t	nfscl_accesscache_load_done_id;
101 #endif /* !KDTRACE_HOOKS */
102 
103 /* Defs */
104 #define	TRUE	1
105 #define	FALSE	0
106 
107 extern struct nfsstatsv1 nfsstatsv1;
108 extern int nfsrv_useacl;
109 extern int nfscl_debuglevel;
110 MALLOC_DECLARE(M_NEWNFSREQ);
111 
112 static vop_read_t	nfsfifo_read;
113 static vop_write_t	nfsfifo_write;
114 static vop_close_t	nfsfifo_close;
115 static int	nfs_setattrrpc(struct vnode *, struct vattr *, struct ucred *,
116 		    struct thread *);
117 static vop_lookup_t	nfs_lookup;
118 static vop_create_t	nfs_create;
119 static vop_mknod_t	nfs_mknod;
120 static vop_open_t	nfs_open;
121 static vop_pathconf_t	nfs_pathconf;
122 static vop_close_t	nfs_close;
123 static vop_access_t	nfs_access;
124 static vop_getattr_t	nfs_getattr;
125 static vop_setattr_t	nfs_setattr;
126 static vop_read_t	nfs_read;
127 static vop_fsync_t	nfs_fsync;
128 static vop_remove_t	nfs_remove;
129 static vop_link_t	nfs_link;
130 static vop_rename_t	nfs_rename;
131 static vop_mkdir_t	nfs_mkdir;
132 static vop_rmdir_t	nfs_rmdir;
133 static vop_symlink_t	nfs_symlink;
134 static vop_readdir_t	nfs_readdir;
135 static vop_strategy_t	nfs_strategy;
136 static	int	nfs_lookitup(struct vnode *, char *, int,
137 		    struct ucred *, struct thread *, struct nfsnode **);
138 static	int	nfs_sillyrename(struct vnode *, struct vnode *,
139 		    struct componentname *);
140 static vop_access_t	nfsspec_access;
141 static vop_readlink_t	nfs_readlink;
142 static vop_print_t	nfs_print;
143 static vop_advlock_t	nfs_advlock;
144 static vop_advlockasync_t nfs_advlockasync;
145 static vop_getacl_t nfs_getacl;
146 static vop_setacl_t nfs_setacl;
147 static vop_advise_t nfs_advise;
148 static vop_allocate_t nfs_allocate;
149 static vop_deallocate_t nfs_deallocate;
150 static vop_copy_file_range_t nfs_copy_file_range;
151 static vop_ioctl_t nfs_ioctl;
152 static vop_getextattr_t nfs_getextattr;
153 static vop_setextattr_t nfs_setextattr;
154 static vop_listextattr_t nfs_listextattr;
155 static vop_deleteextattr_t nfs_deleteextattr;
156 static vop_lock1_t	nfs_lock;
157 
158 /*
159  * Global vfs data structures for nfs
160  */
161 
162 static struct vop_vector newnfs_vnodeops_nosig = {
163 	.vop_default =		&default_vnodeops,
164 	.vop_access =		nfs_access,
165 	.vop_advlock =		nfs_advlock,
166 	.vop_advlockasync =	nfs_advlockasync,
167 	.vop_close =		nfs_close,
168 	.vop_create =		nfs_create,
169 	.vop_fsync =		nfs_fsync,
170 	.vop_getattr =		nfs_getattr,
171 	.vop_getpages =		ncl_getpages,
172 	.vop_putpages =		ncl_putpages,
173 	.vop_inactive =		ncl_inactive,
174 	.vop_link =		nfs_link,
175 	.vop_lock1 =		nfs_lock,
176 	.vop_lookup =		nfs_lookup,
177 	.vop_mkdir =		nfs_mkdir,
178 	.vop_mknod =		nfs_mknod,
179 	.vop_open =		nfs_open,
180 	.vop_pathconf =		nfs_pathconf,
181 	.vop_print =		nfs_print,
182 	.vop_read =		nfs_read,
183 	.vop_readdir =		nfs_readdir,
184 	.vop_readlink =		nfs_readlink,
185 	.vop_reclaim =		ncl_reclaim,
186 	.vop_remove =		nfs_remove,
187 	.vop_rename =		nfs_rename,
188 	.vop_rmdir =		nfs_rmdir,
189 	.vop_setattr =		nfs_setattr,
190 	.vop_strategy =		nfs_strategy,
191 	.vop_symlink =		nfs_symlink,
192 	.vop_write =		ncl_write,
193 	.vop_getacl =		nfs_getacl,
194 	.vop_setacl =		nfs_setacl,
195 	.vop_advise =		nfs_advise,
196 	.vop_allocate =		nfs_allocate,
197 	.vop_deallocate =	nfs_deallocate,
198 	.vop_copy_file_range =	nfs_copy_file_range,
199 	.vop_ioctl =		nfs_ioctl,
200 	.vop_getextattr =	nfs_getextattr,
201 	.vop_setextattr =	nfs_setextattr,
202 	.vop_listextattr =	nfs_listextattr,
203 	.vop_deleteextattr =	nfs_deleteextattr,
204 };
205 VFS_VOP_VECTOR_REGISTER(newnfs_vnodeops_nosig);
206 
207 static int
208 nfs_vnodeops_bypass(struct vop_generic_args *a)
209 {
210 
211 	return (vop_sigdefer(&newnfs_vnodeops_nosig, a));
212 }
213 
214 struct vop_vector newnfs_vnodeops = {
215 	.vop_default =		&default_vnodeops,
216 	.vop_bypass =		nfs_vnodeops_bypass,
217 };
218 VFS_VOP_VECTOR_REGISTER(newnfs_vnodeops);
219 
220 static struct vop_vector newnfs_fifoops_nosig = {
221 	.vop_default =		&fifo_specops,
222 	.vop_access =		nfsspec_access,
223 	.vop_close =		nfsfifo_close,
224 	.vop_fsync =		nfs_fsync,
225 	.vop_getattr =		nfs_getattr,
226 	.vop_inactive =		ncl_inactive,
227 	.vop_pathconf =		nfs_pathconf,
228 	.vop_print =		nfs_print,
229 	.vop_read =		nfsfifo_read,
230 	.vop_reclaim =		ncl_reclaim,
231 	.vop_setattr =		nfs_setattr,
232 	.vop_write =		nfsfifo_write,
233 };
234 VFS_VOP_VECTOR_REGISTER(newnfs_fifoops_nosig);
235 
236 static int
237 nfs_fifoops_bypass(struct vop_generic_args *a)
238 {
239 
240 	return (vop_sigdefer(&newnfs_fifoops_nosig, a));
241 }
242 
243 struct vop_vector newnfs_fifoops = {
244 	.vop_default =		&default_vnodeops,
245 	.vop_bypass =		nfs_fifoops_bypass,
246 };
247 VFS_VOP_VECTOR_REGISTER(newnfs_fifoops);
248 
249 static int nfs_mknodrpc(struct vnode *dvp, struct vnode **vpp,
250     struct componentname *cnp, struct vattr *vap);
251 static int nfs_removerpc(struct vnode *dvp, struct vnode *vp, char *name,
252     int namelen, struct ucred *cred, struct thread *td);
253 static int nfs_renamerpc(struct vnode *fdvp, struct vnode *fvp,
254     char *fnameptr, int fnamelen, struct vnode *tdvp, struct vnode *tvp,
255     char *tnameptr, int tnamelen, struct ucred *cred, struct thread *td);
256 static int nfs_renameit(struct vnode *sdvp, struct vnode *svp,
257     struct componentname *scnp, struct sillyrename *sp);
258 
259 /*
260  * Global variables
261  */
262 SYSCTL_DECL(_vfs_nfs);
263 
264 static int	nfsaccess_cache_timeout = NFS_MAXATTRTIMO;
265 SYSCTL_INT(_vfs_nfs, OID_AUTO, access_cache_timeout, CTLFLAG_RW,
266 	   &nfsaccess_cache_timeout, 0, "NFS ACCESS cache timeout");
267 
268 static int	nfs_prime_access_cache = 0;
269 SYSCTL_INT(_vfs_nfs, OID_AUTO, prime_access_cache, CTLFLAG_RW,
270 	   &nfs_prime_access_cache, 0,
271 	   "Prime NFS ACCESS cache when fetching attributes");
272 
273 static int	newnfs_commit_on_close = 0;
274 SYSCTL_INT(_vfs_nfs, OID_AUTO, commit_on_close, CTLFLAG_RW,
275     &newnfs_commit_on_close, 0, "write+commit on close, else only write");
276 
277 static int	nfs_clean_pages_on_close = 1;
278 SYSCTL_INT(_vfs_nfs, OID_AUTO, clean_pages_on_close, CTLFLAG_RW,
279 	   &nfs_clean_pages_on_close, 0, "NFS clean dirty pages on close");
280 
281 int newnfs_directio_enable = 0;
282 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_directio_enable, CTLFLAG_RW,
283 	   &newnfs_directio_enable, 0, "Enable NFS directio");
284 
285 int nfs_keep_dirty_on_error;
286 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_keep_dirty_on_error, CTLFLAG_RW,
287     &nfs_keep_dirty_on_error, 0, "Retry pageout if error returned");
288 
289 /*
290  * This sysctl allows other processes to mmap a file that has been opened
291  * O_DIRECT by a process.  In general, having processes mmap the file while
292  * Direct IO is in progress can lead to Data Inconsistencies.  But, we allow
293  * this by default to prevent DoS attacks - to prevent a malicious user from
294  * opening up files O_DIRECT preventing other users from mmap'ing these
295  * files.  "Protected" environments where stricter consistency guarantees are
296  * required can disable this knob.  The process that opened the file O_DIRECT
297  * cannot mmap() the file, because mmap'ed IO on an O_DIRECT open() is not
298  * meaningful.
299  */
300 int newnfs_directio_allow_mmap = 1;
301 SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_directio_allow_mmap, CTLFLAG_RW,
302 	   &newnfs_directio_allow_mmap, 0, "Enable mmaped IO on file with O_DIRECT opens");
303 
304 static uint64_t	nfs_maxalloclen = 64 * 1024 * 1024;
305 SYSCTL_U64(_vfs_nfs, OID_AUTO, maxalloclen, CTLFLAG_RW,
306 	   &nfs_maxalloclen, 0, "NFS max allocate/deallocate length");
307 
308 #define	NFSACCESS_ALL (NFSACCESS_READ | NFSACCESS_MODIFY		\
309 			 | NFSACCESS_EXTEND | NFSACCESS_EXECUTE	\
310 			 | NFSACCESS_DELETE | NFSACCESS_LOOKUP)
311 
312 /*
313  * SMP Locking Note :
314  * The list of locks after the description of the lock is the ordering
315  * of other locks acquired with the lock held.
316  * np->n_mtx : Protects the fields in the nfsnode.
317        VM Object Lock
318        VI_MTX (acquired indirectly)
319  * nmp->nm_mtx : Protects the fields in the nfsmount.
320        rep->r_mtx
321  * ncl_iod_mutex : Global lock, protects shared nfsiod state.
322  * nfs_reqq_mtx : Global lock, protects the nfs_reqq list.
323        nmp->nm_mtx
324        rep->r_mtx
325  * rep->r_mtx : Protects the fields in an nfsreq.
326  */
327 
328 static int
329 nfs_lock(struct vop_lock1_args *ap)
330 {
331 	struct vnode *vp;
332 	struct nfsnode *np;
333 	u_quad_t nsize;
334 	int error, lktype;
335 	bool onfault;
336 
337 	vp = ap->a_vp;
338 	lktype = ap->a_flags & LK_TYPE_MASK;
339 	error = VOP_LOCK1_APV(&default_vnodeops, ap);
340 	if (error != 0 || vp->v_op != &newnfs_vnodeops)
341 		return (error);
342 	np = VTONFS(vp);
343 	if (np == NULL)
344 		return (0);
345 	NFSLOCKNODE(np);
346 	if ((np->n_flag & NVNSETSZSKIP) == 0 || (lktype != LK_SHARED &&
347 	    lktype != LK_EXCLUSIVE && lktype != LK_UPGRADE &&
348 	    lktype != LK_TRYUPGRADE)) {
349 		NFSUNLOCKNODE(np);
350 		return (0);
351 	}
352 	onfault = (ap->a_flags & LK_EATTR_MASK) == LK_NOWAIT &&
353 	    (ap->a_flags & LK_INIT_MASK) == LK_CANRECURSE &&
354 	    (lktype == LK_SHARED || lktype == LK_EXCLUSIVE);
355 	if (onfault && vp->v_vnlock->lk_recurse == 0) {
356 		/*
357 		 * Force retry in vm_fault(), to make the lock request
358 		 * sleepable, which allows us to piggy-back the
359 		 * sleepable call to vnode_pager_setsize().
360 		 */
361 		NFSUNLOCKNODE(np);
362 		VOP_UNLOCK(vp);
363 		return (EBUSY);
364 	}
365 	if ((ap->a_flags & LK_NOWAIT) != 0 ||
366 	    (lktype == LK_SHARED && vp->v_vnlock->lk_recurse > 0)) {
367 		NFSUNLOCKNODE(np);
368 		return (0);
369 	}
370 	if (lktype == LK_SHARED) {
371 		NFSUNLOCKNODE(np);
372 		VOP_UNLOCK(vp);
373 		ap->a_flags &= ~(LK_TYPE_MASK | LK_INTERLOCK);
374 		ap->a_flags |= LK_EXCLUSIVE;
375 		error = VOP_LOCK1_APV(&default_vnodeops, ap);
376 		if (error != 0 || vp->v_op != &newnfs_vnodeops)
377 			return (error);
378 		if (vp->v_data == NULL)
379 			goto downgrade;
380 		MPASS(vp->v_data == np);
381 		NFSLOCKNODE(np);
382 		if ((np->n_flag & NVNSETSZSKIP) == 0) {
383 			NFSUNLOCKNODE(np);
384 			goto downgrade;
385 		}
386 	}
387 	np->n_flag &= ~NVNSETSZSKIP;
388 	nsize = np->n_size;
389 	NFSUNLOCKNODE(np);
390 	vnode_pager_setsize(vp, nsize);
391 downgrade:
392 	if (lktype == LK_SHARED) {
393 		ap->a_flags &= ~(LK_TYPE_MASK | LK_INTERLOCK);
394 		ap->a_flags |= LK_DOWNGRADE;
395 		(void)VOP_LOCK1_APV(&default_vnodeops, ap);
396 	}
397 	return (0);
398 }
399 
400 static int
401 nfs34_access_otw(struct vnode *vp, int wmode, struct thread *td,
402     struct ucred *cred, u_int32_t *retmode)
403 {
404 	int error = 0, attrflag, i, lrupos;
405 	u_int32_t rmode;
406 	struct nfsnode *np = VTONFS(vp);
407 	struct nfsvattr nfsva;
408 
409 	error = nfsrpc_accessrpc(vp, wmode, cred, td, &nfsva, &attrflag,
410 	    &rmode);
411 	if (attrflag)
412 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
413 	if (!error) {
414 		lrupos = 0;
415 		NFSLOCKNODE(np);
416 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++) {
417 			if (np->n_accesscache[i].uid == cred->cr_uid) {
418 				np->n_accesscache[i].mode = rmode;
419 				np->n_accesscache[i].stamp = time_second;
420 				break;
421 			}
422 			if (i > 0 && np->n_accesscache[i].stamp <
423 			    np->n_accesscache[lrupos].stamp)
424 				lrupos = i;
425 		}
426 		if (i == NFS_ACCESSCACHESIZE) {
427 			np->n_accesscache[lrupos].uid = cred->cr_uid;
428 			np->n_accesscache[lrupos].mode = rmode;
429 			np->n_accesscache[lrupos].stamp = time_second;
430 		}
431 		NFSUNLOCKNODE(np);
432 		if (retmode != NULL)
433 			*retmode = rmode;
434 		KDTRACE_NFS_ACCESSCACHE_LOAD_DONE(vp, cred->cr_uid, rmode, 0);
435 	} else if (NFS_ISV4(vp)) {
436 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
437 	}
438 #ifdef KDTRACE_HOOKS
439 	if (error != 0)
440 		KDTRACE_NFS_ACCESSCACHE_LOAD_DONE(vp, cred->cr_uid, 0,
441 		    error);
442 #endif
443 	return (error);
444 }
445 
446 /*
447  * nfs access vnode op.
448  * For nfs version 2, just return ok. File accesses may fail later.
449  * For nfs version 3, use the access rpc to check accessibility. If file modes
450  * are changed on the server, accesses might still fail later.
451  */
452 static int
453 nfs_access(struct vop_access_args *ap)
454 {
455 	struct vnode *vp = ap->a_vp;
456 	int error = 0, i, gotahit;
457 	u_int32_t mode, wmode, rmode;
458 	int v34 = NFS_ISV34(vp);
459 	struct nfsnode *np = VTONFS(vp);
460 
461 	/*
462 	 * Disallow write attempts on filesystems mounted read-only;
463 	 * unless the file is a socket, fifo, or a block or character
464 	 * device resident on the filesystem.
465 	 */
466 	if ((ap->a_accmode & (VWRITE | VAPPEND | VWRITE_NAMED_ATTRS |
467 	    VDELETE_CHILD | VWRITE_ATTRIBUTES | VDELETE | VWRITE_ACL |
468 	    VWRITE_OWNER)) != 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) != 0) {
469 		switch (vp->v_type) {
470 		case VREG:
471 		case VDIR:
472 		case VLNK:
473 			return (EROFS);
474 		default:
475 			break;
476 		}
477 	}
478 	/*
479 	 * For nfs v3 or v4, check to see if we have done this recently, and if
480 	 * so return our cached result instead of making an ACCESS call.
481 	 * If not, do an access rpc, otherwise you are stuck emulating
482 	 * ufs_access() locally using the vattr. This may not be correct,
483 	 * since the server may apply other access criteria such as
484 	 * client uid-->server uid mapping that we do not know about.
485 	 */
486 	if (v34) {
487 		if (ap->a_accmode & VREAD)
488 			mode = NFSACCESS_READ;
489 		else
490 			mode = 0;
491 		if (vp->v_type != VDIR) {
492 			if (ap->a_accmode & VWRITE)
493 				mode |= (NFSACCESS_MODIFY | NFSACCESS_EXTEND);
494 			if (ap->a_accmode & VAPPEND)
495 				mode |= NFSACCESS_EXTEND;
496 			if (ap->a_accmode & VEXEC)
497 				mode |= NFSACCESS_EXECUTE;
498 			if (ap->a_accmode & VDELETE)
499 				mode |= NFSACCESS_DELETE;
500 		} else {
501 			if (ap->a_accmode & VWRITE)
502 				mode |= (NFSACCESS_MODIFY | NFSACCESS_EXTEND);
503 			if (ap->a_accmode & VAPPEND)
504 				mode |= NFSACCESS_EXTEND;
505 			if (ap->a_accmode & VEXEC)
506 				mode |= NFSACCESS_LOOKUP;
507 			if (ap->a_accmode & VDELETE)
508 				mode |= NFSACCESS_DELETE;
509 			if (ap->a_accmode & VDELETE_CHILD)
510 				mode |= NFSACCESS_MODIFY;
511 		}
512 		/* XXX safety belt, only make blanket request if caching */
513 		if (nfsaccess_cache_timeout > 0) {
514 			wmode = NFSACCESS_READ | NFSACCESS_MODIFY |
515 				NFSACCESS_EXTEND | NFSACCESS_EXECUTE |
516 				NFSACCESS_DELETE | NFSACCESS_LOOKUP;
517 		} else {
518 			wmode = mode;
519 		}
520 
521 		/*
522 		 * Does our cached result allow us to give a definite yes to
523 		 * this request?
524 		 */
525 		gotahit = 0;
526 		NFSLOCKNODE(np);
527 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++) {
528 			if (ap->a_cred->cr_uid == np->n_accesscache[i].uid) {
529 			    if (time_second < (np->n_accesscache[i].stamp
530 				+ nfsaccess_cache_timeout) &&
531 				(np->n_accesscache[i].mode & mode) == mode) {
532 				NFSINCRGLOBAL(nfsstatsv1.accesscache_hits);
533 				gotahit = 1;
534 			    }
535 			    break;
536 			}
537 		}
538 		NFSUNLOCKNODE(np);
539 #ifdef KDTRACE_HOOKS
540 		if (gotahit != 0)
541 			KDTRACE_NFS_ACCESSCACHE_GET_HIT(vp,
542 			    ap->a_cred->cr_uid, mode);
543 		else
544 			KDTRACE_NFS_ACCESSCACHE_GET_MISS(vp,
545 			    ap->a_cred->cr_uid, mode);
546 #endif
547 		if (gotahit == 0) {
548 			/*
549 			 * Either a no, or a don't know.  Go to the wire.
550 			 */
551 			NFSINCRGLOBAL(nfsstatsv1.accesscache_misses);
552 		        error = nfs34_access_otw(vp, wmode, ap->a_td,
553 			    ap->a_cred, &rmode);
554 			if (!error &&
555 			    (rmode & mode) != mode)
556 				error = EACCES;
557 		}
558 		return (error);
559 	} else {
560 		if ((error = nfsspec_access(ap)) != 0) {
561 			return (error);
562 		}
563 		/*
564 		 * Attempt to prevent a mapped root from accessing a file
565 		 * which it shouldn't.  We try to read a byte from the file
566 		 * if the user is root and the file is not zero length.
567 		 * After calling nfsspec_access, we should have the correct
568 		 * file size cached.
569 		 */
570 		NFSLOCKNODE(np);
571 		if (ap->a_cred->cr_uid == 0 && (ap->a_accmode & VREAD)
572 		    && VTONFS(vp)->n_size > 0) {
573 			struct iovec aiov;
574 			struct uio auio;
575 			char buf[1];
576 
577 			NFSUNLOCKNODE(np);
578 			aiov.iov_base = buf;
579 			aiov.iov_len = 1;
580 			auio.uio_iov = &aiov;
581 			auio.uio_iovcnt = 1;
582 			auio.uio_offset = 0;
583 			auio.uio_resid = 1;
584 			auio.uio_segflg = UIO_SYSSPACE;
585 			auio.uio_rw = UIO_READ;
586 			auio.uio_td = ap->a_td;
587 
588 			if (vp->v_type == VREG)
589 				error = ncl_readrpc(vp, &auio, ap->a_cred);
590 			else if (vp->v_type == VDIR) {
591 				char* bp;
592 				bp = malloc(NFS_DIRBLKSIZ, M_TEMP, M_WAITOK);
593 				aiov.iov_base = bp;
594 				aiov.iov_len = auio.uio_resid = NFS_DIRBLKSIZ;
595 				error = ncl_readdirrpc(vp, &auio, ap->a_cred,
596 				    ap->a_td);
597 				free(bp, M_TEMP);
598 			} else if (vp->v_type == VLNK)
599 				error = ncl_readlinkrpc(vp, &auio, ap->a_cred);
600 			else
601 				error = EACCES;
602 		} else
603 			NFSUNLOCKNODE(np);
604 		return (error);
605 	}
606 }
607 
608 /*
609  * nfs open vnode op
610  * Check to see if the type is ok
611  * and that deletion is not in progress.
612  * For paged in text files, you will need to flush the page cache
613  * if consistency is lost.
614  */
615 /* ARGSUSED */
616 static int
617 nfs_open(struct vop_open_args *ap)
618 {
619 	struct vnode *vp = ap->a_vp;
620 	struct nfsnode *np = VTONFS(vp);
621 	struct vattr vattr;
622 	int error;
623 	int fmode = ap->a_mode;
624 	struct ucred *cred;
625 	vm_object_t obj;
626 
627 	if (vp->v_type != VREG && vp->v_type != VDIR && vp->v_type != VLNK)
628 		return (EOPNOTSUPP);
629 
630 	/*
631 	 * For NFSv4, we need to do the Open Op before cache validation,
632 	 * so that we conform to RFC3530 Sec. 9.3.1.
633 	 */
634 	if (NFS_ISV4(vp)) {
635 		error = nfsrpc_open(vp, fmode, ap->a_cred, ap->a_td);
636 		if (error) {
637 			error = nfscl_maperr(ap->a_td, error, (uid_t)0,
638 			    (gid_t)0);
639 			return (error);
640 		}
641 	}
642 
643 	/*
644 	 * Now, if this Open will be doing reading, re-validate/flush the
645 	 * cache, so that Close/Open coherency is maintained.
646 	 */
647 	NFSLOCKNODE(np);
648 	if (np->n_flag & NMODIFIED) {
649 		NFSUNLOCKNODE(np);
650 		if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
651 			NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
652 			if (VN_IS_DOOMED(vp))
653 				return (EBADF);
654 		}
655 		error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
656 		if (error == EINTR || error == EIO) {
657 			if (NFS_ISV4(vp))
658 				(void) nfsrpc_close(vp, 0, ap->a_td);
659 			return (error);
660 		}
661 		NFSLOCKNODE(np);
662 		np->n_attrstamp = 0;
663 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
664 		if (vp->v_type == VDIR)
665 			np->n_direofoffset = 0;
666 		NFSUNLOCKNODE(np);
667 		error = VOP_GETATTR(vp, &vattr, ap->a_cred);
668 		if (error) {
669 			if (NFS_ISV4(vp))
670 				(void) nfsrpc_close(vp, 0, ap->a_td);
671 			return (error);
672 		}
673 		NFSLOCKNODE(np);
674 		np->n_mtime = vattr.va_mtime;
675 		if (NFS_ISV4(vp))
676 			np->n_change = vattr.va_filerev;
677 	} else {
678 		NFSUNLOCKNODE(np);
679 		error = VOP_GETATTR(vp, &vattr, ap->a_cred);
680 		if (error) {
681 			if (NFS_ISV4(vp))
682 				(void) nfsrpc_close(vp, 0, ap->a_td);
683 			return (error);
684 		}
685 		NFSLOCKNODE(np);
686 		if ((NFS_ISV4(vp) && np->n_change != vattr.va_filerev) ||
687 		    NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime)) {
688 			if (vp->v_type == VDIR)
689 				np->n_direofoffset = 0;
690 			NFSUNLOCKNODE(np);
691 			if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
692 				NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
693 				if (VN_IS_DOOMED(vp))
694 					return (EBADF);
695 			}
696 			error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
697 			if (error == EINTR || error == EIO) {
698 				if (NFS_ISV4(vp))
699 					(void) nfsrpc_close(vp, 0, ap->a_td);
700 				return (error);
701 			}
702 			NFSLOCKNODE(np);
703 			np->n_mtime = vattr.va_mtime;
704 			if (NFS_ISV4(vp))
705 				np->n_change = vattr.va_filerev;
706 		}
707 	}
708 
709 	/*
710 	 * If the object has >= 1 O_DIRECT active opens, we disable caching.
711 	 */
712 	if (newnfs_directio_enable && (fmode & O_DIRECT) &&
713 	    (vp->v_type == VREG)) {
714 		if (np->n_directio_opens == 0) {
715 			NFSUNLOCKNODE(np);
716 			if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
717 				NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
718 				if (VN_IS_DOOMED(vp))
719 					return (EBADF);
720 			}
721 			error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
722 			if (error) {
723 				if (NFS_ISV4(vp))
724 					(void) nfsrpc_close(vp, 0, ap->a_td);
725 				return (error);
726 			}
727 			NFSLOCKNODE(np);
728 			np->n_flag |= NNONCACHE;
729 		}
730 		np->n_directio_opens++;
731 	}
732 
733 	/* If opened for writing via NFSv4.1 or later, mark that for pNFS. */
734 	if (NFSHASPNFS(VFSTONFS(vp->v_mount)) && (fmode & FWRITE) != 0)
735 		np->n_flag |= NWRITEOPENED;
736 
737 	/*
738 	 * If this is an open for writing, capture a reference to the
739 	 * credentials, so they can be used by ncl_putpages(). Using
740 	 * these write credentials is preferable to the credentials of
741 	 * whatever thread happens to be doing the VOP_PUTPAGES() since
742 	 * the write RPCs are less likely to fail with EACCES.
743 	 */
744 	if ((fmode & FWRITE) != 0) {
745 		cred = np->n_writecred;
746 		np->n_writecred = crhold(ap->a_cred);
747 	} else
748 		cred = NULL;
749 	NFSUNLOCKNODE(np);
750 
751 	if (cred != NULL)
752 		crfree(cred);
753 	vnode_create_vobject(vp, vattr.va_size, ap->a_td);
754 
755 	/*
756 	 * If the text file has been mmap'd, flush any dirty pages to the
757 	 * buffer cache and then...
758 	 * Make sure all writes are pushed to the NFS server.  If this is not
759 	 * done, the modify time of the file can change while the text
760 	 * file is being executed.  This will cause the process that is
761 	 * executing the text file to be terminated.
762 	 */
763 	if (vp->v_writecount <= -1) {
764 		if ((obj = vp->v_object) != NULL &&
765 		    vm_object_mightbedirty(obj)) {
766 			if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
767 				NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
768 				if (VN_IS_DOOMED(vp))
769 					return (EBADF);
770 			}
771 			VM_OBJECT_WLOCK(obj);
772 			vm_object_page_clean(obj, 0, 0, OBJPC_SYNC);
773 			VM_OBJECT_WUNLOCK(obj);
774 		}
775 
776 		/* Now, flush the buffer cache. */
777 		ncl_flush(vp, MNT_WAIT, curthread, 0, 0);
778 
779 		/* And, finally, make sure that n_mtime is up to date. */
780 		np = VTONFS(vp);
781 		NFSLOCKNODE(np);
782 		np->n_mtime = np->n_vattr.na_mtime;
783 		NFSUNLOCKNODE(np);
784 	}
785 	return (0);
786 }
787 
788 /*
789  * nfs close vnode op
790  * What an NFS client should do upon close after writing is a debatable issue.
791  * Most NFS clients push delayed writes to the server upon close, basically for
792  * two reasons:
793  * 1 - So that any write errors may be reported back to the client process
794  *     doing the close system call. By far the two most likely errors are
795  *     NFSERR_NOSPC and NFSERR_DQUOT to indicate space allocation failure.
796  * 2 - To put a worst case upper bound on cache inconsistency between
797  *     multiple clients for the file.
798  * There is also a consistency problem for Version 2 of the protocol w.r.t.
799  * not being able to tell if other clients are writing a file concurrently,
800  * since there is no way of knowing if the changed modify time in the reply
801  * is only due to the write for this client.
802  * (NFS Version 3 provides weak cache consistency data in the reply that
803  *  should be sufficient to detect and handle this case.)
804  *
805  * The current code does the following:
806  * for NFS Version 2 - play it safe and flush/invalidate all dirty buffers
807  * for NFS Version 3 - flush dirty buffers to the server but don't invalidate
808  *                     or commit them (this satisfies 1 and 2 except for the
809  *                     case where the server crashes after this close but
810  *                     before the commit RPC, which is felt to be "good
811  *                     enough". Changing the last argument to ncl_flush() to
812  *                     a 1 would force a commit operation, if it is felt a
813  *                     commit is necessary now.
814  * for NFS Version 4 - flush the dirty buffers and commit them, if
815  *		       nfscl_mustflush() says this is necessary.
816  *                     It is necessary if there is no write delegation held,
817  *                     in order to satisfy open/close coherency.
818  *                     If the file isn't cached on local stable storage,
819  *                     it may be necessary in order to detect "out of space"
820  *                     errors from the server, if the write delegation
821  *                     issued by the server doesn't allow the file to grow.
822  */
823 /* ARGSUSED */
824 static int
825 nfs_close(struct vop_close_args *ap)
826 {
827 	struct vnode *vp = ap->a_vp;
828 	struct nfsnode *np = VTONFS(vp);
829 	struct nfsvattr nfsva;
830 	struct ucred *cred;
831 	int error = 0, ret, localcred = 0;
832 	int fmode = ap->a_fflag;
833 
834 	if (NFSCL_FORCEDISM(vp->v_mount))
835 		return (0);
836 	/*
837 	 * During shutdown, a_cred isn't valid, so just use root.
838 	 */
839 	if (ap->a_cred == NOCRED) {
840 		cred = newnfs_getcred();
841 		localcred = 1;
842 	} else {
843 		cred = ap->a_cred;
844 	}
845 	if (vp->v_type == VREG) {
846 	    /*
847 	     * Examine and clean dirty pages, regardless of NMODIFIED.
848 	     * This closes a major hole in close-to-open consistency.
849 	     * We want to push out all dirty pages (and buffers) on
850 	     * close, regardless of whether they were dirtied by
851 	     * mmap'ed writes or via write().
852 	     */
853 	    if (nfs_clean_pages_on_close && vp->v_object) {
854 		if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
855 			NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
856 			if (VN_IS_DOOMED(vp) && ap->a_fflag != FNONBLOCK)
857 				return (EBADF);
858 		}
859 		VM_OBJECT_WLOCK(vp->v_object);
860 		vm_object_page_clean(vp->v_object, 0, 0, 0);
861 		VM_OBJECT_WUNLOCK(vp->v_object);
862 	    }
863 	    NFSLOCKNODE(np);
864 	    if (np->n_flag & NMODIFIED) {
865 		NFSUNLOCKNODE(np);
866 		if (NFS_ISV3(vp)) {
867 		    /*
868 		     * Under NFSv3 we have dirty buffers to dispose of.  We
869 		     * must flush them to the NFS server.  We have the option
870 		     * of waiting all the way through the commit rpc or just
871 		     * waiting for the initial write.  The default is to only
872 		     * wait through the initial write so the data is in the
873 		     * server's cache, which is roughly similar to the state
874 		     * a standard disk subsystem leaves the file in on close().
875 		     *
876 		     * We cannot clear the NMODIFIED bit in np->n_flag due to
877 		     * potential races with other processes, and certainly
878 		     * cannot clear it if we don't commit.
879 		     * These races occur when there is no longer the old
880 		     * traditional vnode locking implemented for Vnode Ops.
881 		     */
882 		    int cm = newnfs_commit_on_close ? 1 : 0;
883 		    if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
884 			    NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
885 			    if (VN_IS_DOOMED(vp) && ap->a_fflag != FNONBLOCK)
886 				    return (EBADF);
887 		    }
888 		    error = ncl_flush(vp, MNT_WAIT, ap->a_td, cm, 0);
889 		    /* np->n_flag &= ~NMODIFIED; */
890 		} else if (NFS_ISV4(vp)) {
891 			if (nfscl_mustflush(vp) != 0) {
892 				int cm = newnfs_commit_on_close ? 1 : 0;
893 				if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
894 					NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
895 					if (VN_IS_DOOMED(vp) && ap->a_fflag !=
896 					    FNONBLOCK)
897 						return (EBADF);
898 				}
899 				error = ncl_flush(vp, MNT_WAIT, ap->a_td,
900 				    cm, 0);
901 				/*
902 				 * as above w.r.t races when clearing
903 				 * NMODIFIED.
904 				 * np->n_flag &= ~NMODIFIED;
905 				 */
906 			}
907 		} else {
908 			if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
909 				NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
910 				if (VN_IS_DOOMED(vp) && ap->a_fflag !=
911 				    FNONBLOCK)
912 					return (EBADF);
913 			}
914 			error = ncl_vinvalbuf(vp, V_SAVE, ap->a_td, 1);
915 		}
916 		NFSLOCKNODE(np);
917 	    }
918  	    /*
919  	     * Invalidate the attribute cache in all cases.
920  	     * An open is going to fetch fresh attrs any way, other procs
921  	     * on this node that have file open will be forced to do an
922  	     * otw attr fetch, but this is safe.
923 	     * --> A user found that their RPC count dropped by 20% when
924 	     *     this was commented out and I can't see any requirement
925 	     *     for it, so I've disabled it when negative lookups are
926 	     *     enabled. (What does this have to do with negative lookup
927 	     *     caching? Well nothing, except it was reported by the
928 	     *     same user that needed negative lookup caching and I wanted
929 	     *     there to be a way to disable it to see if it
930 	     *     is the cause of some caching/coherency issue that might
931 	     *     crop up.)
932  	     */
933 	    if (VFSTONFS(vp->v_mount)->nm_negnametimeo == 0) {
934 		    np->n_attrstamp = 0;
935 		    KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
936 	    }
937 	    if (np->n_flag & NWRITEERR) {
938 		np->n_flag &= ~NWRITEERR;
939 		error = np->n_error;
940 	    }
941 	    NFSUNLOCKNODE(np);
942 	}
943 
944 	if (NFS_ISV4(vp)) {
945 		/*
946 		 * Get attributes so "change" is up to date.
947 		 */
948 		if (error == 0 && nfscl_mustflush(vp) != 0 &&
949 		    vp->v_type == VREG &&
950 		    (VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NOCTO) == 0) {
951 			ret = nfsrpc_getattr(vp, cred, ap->a_td, &nfsva);
952 			if (!ret) {
953 				np->n_change = nfsva.na_filerev;
954 				(void) nfscl_loadattrcache(&vp, &nfsva, NULL,
955 				    0, 0);
956 			}
957 		}
958 
959 		/*
960 		 * and do the close.
961 		 */
962 		ret = nfsrpc_close(vp, 0, ap->a_td);
963 		if (!error && ret)
964 			error = ret;
965 		if (error)
966 			error = nfscl_maperr(ap->a_td, error, (uid_t)0,
967 			    (gid_t)0);
968 	}
969 	if (newnfs_directio_enable)
970 		KASSERT((np->n_directio_asyncwr == 0),
971 			("nfs_close: dirty unflushed (%d) directio buffers\n",
972 			 np->n_directio_asyncwr));
973 	if (newnfs_directio_enable && (fmode & O_DIRECT) && (vp->v_type == VREG)) {
974 		NFSLOCKNODE(np);
975 		KASSERT((np->n_directio_opens > 0),
976 			("nfs_close: unexpectedly value (0) of n_directio_opens\n"));
977 		np->n_directio_opens--;
978 		if (np->n_directio_opens == 0)
979 			np->n_flag &= ~NNONCACHE;
980 		NFSUNLOCKNODE(np);
981 	}
982 	if (localcred)
983 		NFSFREECRED(cred);
984 	return (error);
985 }
986 
987 /*
988  * nfs getattr call from vfs.
989  */
990 static int
991 nfs_getattr(struct vop_getattr_args *ap)
992 {
993 	struct vnode *vp = ap->a_vp;
994 	struct thread *td = curthread;	/* XXX */
995 	struct nfsnode *np = VTONFS(vp);
996 	int error = 0;
997 	struct nfsvattr nfsva;
998 	struct vattr *vap = ap->a_vap;
999 	struct vattr vattr;
1000 
1001 	/*
1002 	 * Update local times for special files.
1003 	 */
1004 	NFSLOCKNODE(np);
1005 	if (np->n_flag & (NACC | NUPD))
1006 		np->n_flag |= NCHG;
1007 	NFSUNLOCKNODE(np);
1008 	/*
1009 	 * First look in the cache.
1010 	 */
1011 	if (ncl_getattrcache(vp, &vattr) == 0) {
1012 		ncl_copy_vattr(vap, &vattr);
1013 
1014 		/*
1015 		 * Get the local modify time for the case of a write
1016 		 * delegation.
1017 		 */
1018 		nfscl_deleggetmodtime(vp, &vap->va_mtime);
1019 		return (0);
1020 	}
1021 
1022 	if (NFS_ISV34(vp) && nfs_prime_access_cache &&
1023 	    nfsaccess_cache_timeout > 0) {
1024 		NFSINCRGLOBAL(nfsstatsv1.accesscache_misses);
1025 		nfs34_access_otw(vp, NFSACCESS_ALL, td, ap->a_cred, NULL);
1026 		if (ncl_getattrcache(vp, ap->a_vap) == 0) {
1027 			nfscl_deleggetmodtime(vp, &ap->a_vap->va_mtime);
1028 			return (0);
1029 		}
1030 	}
1031 	error = nfsrpc_getattr(vp, ap->a_cred, td, &nfsva);
1032 	if (!error)
1033 		error = nfscl_loadattrcache(&vp, &nfsva, vap, 0, 0);
1034 	if (!error) {
1035 		/*
1036 		 * Get the local modify time for the case of a write
1037 		 * delegation.
1038 		 */
1039 		nfscl_deleggetmodtime(vp, &vap->va_mtime);
1040 	} else if (NFS_ISV4(vp)) {
1041 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
1042 	}
1043 	return (error);
1044 }
1045 
1046 /*
1047  * nfs setattr call.
1048  */
1049 static int
1050 nfs_setattr(struct vop_setattr_args *ap)
1051 {
1052 	struct vnode *vp = ap->a_vp;
1053 	struct nfsnode *np = VTONFS(vp);
1054 	struct thread *td = curthread;	/* XXX */
1055 	struct vattr *vap = ap->a_vap;
1056 	int error = 0;
1057 	u_quad_t tsize;
1058 	struct timespec ts;
1059 
1060 #ifndef nolint
1061 	tsize = (u_quad_t)0;
1062 #endif
1063 
1064 	/*
1065 	 * Setting of flags and marking of atimes are not supported.
1066 	 */
1067 	if (vap->va_flags != VNOVAL)
1068 		return (EOPNOTSUPP);
1069 
1070 	/*
1071 	 * Disallow write attempts if the filesystem is mounted read-only.
1072 	 */
1073   	if ((vap->va_flags != VNOVAL || vap->va_uid != (uid_t)VNOVAL ||
1074 	    vap->va_gid != (gid_t)VNOVAL || vap->va_atime.tv_sec != VNOVAL ||
1075 	    vap->va_mtime.tv_sec != VNOVAL ||
1076 	    vap->va_birthtime.tv_sec != VNOVAL ||
1077 	    vap->va_mode != (mode_t)VNOVAL) &&
1078 	    (vp->v_mount->mnt_flag & MNT_RDONLY))
1079 		return (EROFS);
1080 	if (vap->va_size != VNOVAL) {
1081  		switch (vp->v_type) {
1082  		case VDIR:
1083  			return (EISDIR);
1084  		case VCHR:
1085  		case VBLK:
1086  		case VSOCK:
1087  		case VFIFO:
1088 			if (vap->va_mtime.tv_sec == VNOVAL &&
1089 			    vap->va_atime.tv_sec == VNOVAL &&
1090 			    vap->va_birthtime.tv_sec == VNOVAL &&
1091 			    vap->va_mode == (mode_t)VNOVAL &&
1092 			    vap->va_uid == (uid_t)VNOVAL &&
1093 			    vap->va_gid == (gid_t)VNOVAL)
1094 				return (0);
1095  			vap->va_size = VNOVAL;
1096  			break;
1097  		default:
1098 			/*
1099 			 * Disallow write attempts if the filesystem is
1100 			 * mounted read-only.
1101 			 */
1102 			if (vp->v_mount->mnt_flag & MNT_RDONLY)
1103 				return (EROFS);
1104 			/*
1105 			 *  We run vnode_pager_setsize() early (why?),
1106 			 * we must set np->n_size now to avoid vinvalbuf
1107 			 * V_SAVE races that might setsize a lower
1108 			 * value.
1109 			 */
1110 			NFSLOCKNODE(np);
1111 			tsize = np->n_size;
1112 			NFSUNLOCKNODE(np);
1113 			error = ncl_meta_setsize(vp, td, vap->va_size);
1114 			NFSLOCKNODE(np);
1115  			if (np->n_flag & NMODIFIED) {
1116 			    tsize = np->n_size;
1117 			    NFSUNLOCKNODE(np);
1118 			    error = ncl_vinvalbuf(vp, vap->va_size == 0 ?
1119 			        0 : V_SAVE, td, 1);
1120 			    if (error != 0) {
1121 				    vnode_pager_setsize(vp, tsize);
1122 				    return (error);
1123 			    }
1124 			    /*
1125 			     * Call nfscl_delegmodtime() to set the modify time
1126 			     * locally, as required.
1127 			     */
1128 			    nfscl_delegmodtime(vp);
1129  			} else
1130 			    NFSUNLOCKNODE(np);
1131 			/*
1132 			 * np->n_size has already been set to vap->va_size
1133 			 * in ncl_meta_setsize(). We must set it again since
1134 			 * nfs_loadattrcache() could be called through
1135 			 * ncl_meta_setsize() and could modify np->n_size.
1136 			 */
1137 			NFSLOCKNODE(np);
1138  			np->n_vattr.na_size = np->n_size = vap->va_size;
1139 			NFSUNLOCKNODE(np);
1140   		}
1141   	} else {
1142 		NFSLOCKNODE(np);
1143 		if ((vap->va_mtime.tv_sec != VNOVAL || vap->va_atime.tv_sec != VNOVAL) &&
1144 		    (np->n_flag & NMODIFIED) && vp->v_type == VREG) {
1145 			NFSUNLOCKNODE(np);
1146 			error = ncl_vinvalbuf(vp, V_SAVE, td, 1);
1147 			if (error == EINTR || error == EIO)
1148 				return (error);
1149 		} else
1150 			NFSUNLOCKNODE(np);
1151 	}
1152 	error = nfs_setattrrpc(vp, vap, ap->a_cred, td);
1153 	if (vap->va_size != VNOVAL) {
1154 		if (error == 0) {
1155 			nanouptime(&ts);
1156 			NFSLOCKNODE(np);
1157 			np->n_localmodtime = ts;
1158 			NFSUNLOCKNODE(np);
1159 		} else {
1160 			NFSLOCKNODE(np);
1161 			np->n_size = np->n_vattr.na_size = tsize;
1162 			vnode_pager_setsize(vp, tsize);
1163 			NFSUNLOCKNODE(np);
1164 		}
1165 	}
1166 	return (error);
1167 }
1168 
1169 /*
1170  * Do an nfs setattr rpc.
1171  */
1172 static int
1173 nfs_setattrrpc(struct vnode *vp, struct vattr *vap, struct ucred *cred,
1174     struct thread *td)
1175 {
1176 	struct nfsnode *np = VTONFS(vp);
1177 	int error, ret, attrflag, i;
1178 	struct nfsvattr nfsva;
1179 
1180 	if (NFS_ISV34(vp)) {
1181 		NFSLOCKNODE(np);
1182 		for (i = 0; i < NFS_ACCESSCACHESIZE; i++)
1183 			np->n_accesscache[i].stamp = 0;
1184 		np->n_flag |= NDELEGMOD;
1185 		NFSUNLOCKNODE(np);
1186 		KDTRACE_NFS_ACCESSCACHE_FLUSH_DONE(vp);
1187 	}
1188 	error = nfsrpc_setattr(vp, vap, NULL, cred, td, &nfsva, &attrflag);
1189 	if (attrflag) {
1190 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
1191 		if (ret && !error)
1192 			error = ret;
1193 	}
1194 	if (error && NFS_ISV4(vp))
1195 		error = nfscl_maperr(td, error, vap->va_uid, vap->va_gid);
1196 	return (error);
1197 }
1198 
1199 /*
1200  * nfs lookup call, one step at a time...
1201  * First look in cache
1202  * If not found, unlock the directory nfsnode and do the rpc
1203  */
1204 static int
1205 nfs_lookup(struct vop_lookup_args *ap)
1206 {
1207 	struct componentname *cnp = ap->a_cnp;
1208 	struct vnode *dvp = ap->a_dvp;
1209 	struct vnode **vpp = ap->a_vpp;
1210 	struct mount *mp = dvp->v_mount;
1211 	int flags = cnp->cn_flags;
1212 	struct vnode *newvp;
1213 	struct nfsmount *nmp;
1214 	struct nfsnode *np, *newnp;
1215 	int error = 0, attrflag, dattrflag, ltype, ncticks;
1216 	struct thread *td = curthread;
1217 	struct nfsfh *nfhp;
1218 	struct nfsvattr dnfsva, nfsva;
1219 	struct vattr vattr;
1220 	struct timespec nctime, ts;
1221 	uint32_t openmode;
1222 
1223 	*vpp = NULLVP;
1224 	if ((flags & ISLASTCN) && (mp->mnt_flag & MNT_RDONLY) &&
1225 	    (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
1226 		return (EROFS);
1227 	if (dvp->v_type != VDIR)
1228 		return (ENOTDIR);
1229 	nmp = VFSTONFS(mp);
1230 	np = VTONFS(dvp);
1231 
1232 	/* For NFSv4, wait until any remove is done. */
1233 	NFSLOCKNODE(np);
1234 	while (NFSHASNFSV4(nmp) && (np->n_flag & NREMOVEINPROG)) {
1235 		np->n_flag |= NREMOVEWANT;
1236 		(void) msleep((caddr_t)np, &np->n_mtx, PZERO, "nfslkup", 0);
1237 	}
1238 	NFSUNLOCKNODE(np);
1239 
1240 	error = vn_dir_check_exec(dvp, cnp);
1241 	if (error != 0)
1242 		return (error);
1243 	error = cache_lookup(dvp, vpp, cnp, &nctime, &ncticks);
1244 	if (error > 0 && error != ENOENT)
1245 		return (error);
1246 	if (error == -1) {
1247 		/*
1248 		 * Lookups of "." are special and always return the
1249 		 * current directory.  cache_lookup() already handles
1250 		 * associated locking bookkeeping, etc.
1251 		 */
1252 		if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
1253 			/* XXX: Is this really correct? */
1254 			if (cnp->cn_nameiop != LOOKUP &&
1255 			    (flags & ISLASTCN))
1256 				cnp->cn_flags |= SAVENAME;
1257 			return (0);
1258 		}
1259 
1260 		/*
1261 		 * We only accept a positive hit in the cache if the
1262 		 * change time of the file matches our cached copy.
1263 		 * Otherwise, we discard the cache entry and fallback
1264 		 * to doing a lookup RPC.  We also only trust cache
1265 		 * entries for less than nm_nametimeo seconds.
1266 		 *
1267 		 * To better handle stale file handles and attributes,
1268 		 * clear the attribute cache of this node if it is a
1269 		 * leaf component, part of an open() call, and not
1270 		 * locally modified before fetching the attributes.
1271 		 * This should allow stale file handles to be detected
1272 		 * here where we can fall back to a LOOKUP RPC to
1273 		 * recover rather than having nfs_open() detect the
1274 		 * stale file handle and failing open(2) with ESTALE.
1275 		 */
1276 		newvp = *vpp;
1277 		newnp = VTONFS(newvp);
1278 		if (!(nmp->nm_flag & NFSMNT_NOCTO) &&
1279 		    (flags & (ISLASTCN | ISOPEN)) == (ISLASTCN | ISOPEN) &&
1280 		    !(newnp->n_flag & NMODIFIED)) {
1281 			NFSLOCKNODE(newnp);
1282 			newnp->n_attrstamp = 0;
1283 			KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(newvp);
1284 			NFSUNLOCKNODE(newnp);
1285 		}
1286 		if (nfscl_nodeleg(newvp, 0) == 0 ||
1287 		    ((u_int)(ticks - ncticks) < (nmp->nm_nametimeo * hz) &&
1288 		    VOP_GETATTR(newvp, &vattr, cnp->cn_cred) == 0 &&
1289 		    timespeccmp(&vattr.va_ctime, &nctime, ==))) {
1290 			NFSINCRGLOBAL(nfsstatsv1.lookupcache_hits);
1291 			if (cnp->cn_nameiop != LOOKUP &&
1292 			    (flags & ISLASTCN))
1293 				cnp->cn_flags |= SAVENAME;
1294 			return (0);
1295 		}
1296 		cache_purge(newvp);
1297 		if (dvp != newvp)
1298 			vput(newvp);
1299 		else
1300 			vrele(newvp);
1301 		*vpp = NULLVP;
1302 	} else if (error == ENOENT) {
1303 		if (VN_IS_DOOMED(dvp))
1304 			return (ENOENT);
1305 		/*
1306 		 * We only accept a negative hit in the cache if the
1307 		 * modification time of the parent directory matches
1308 		 * the cached copy in the name cache entry.
1309 		 * Otherwise, we discard all of the negative cache
1310 		 * entries for this directory.  We also only trust
1311 		 * negative cache entries for up to nm_negnametimeo
1312 		 * seconds.
1313 		 */
1314 		if ((u_int)(ticks - ncticks) < (nmp->nm_negnametimeo * hz) &&
1315 		    VOP_GETATTR(dvp, &vattr, cnp->cn_cred) == 0 &&
1316 		    timespeccmp(&vattr.va_mtime, &nctime, ==)) {
1317 			NFSINCRGLOBAL(nfsstatsv1.lookupcache_hits);
1318 			return (ENOENT);
1319 		}
1320 		cache_purge_negative(dvp);
1321 	}
1322 
1323 	openmode = 0;
1324 	/*
1325 	 * If this an NFSv4.1/4.2 mount using the "oneopenown" mount
1326 	 * option, it is possible to do the Open operation in the same
1327 	 * compound as Lookup, so long as delegations are not being
1328 	 * issued.  This saves doing a separate RPC for Open.
1329 	 * For pnfs, do not do this, since the Open+LayoutGet will
1330 	 * be needed as a separate RPC.
1331 	 */
1332 	NFSLOCKMNT(nmp);
1333 	if (NFSHASNFSV4N(nmp) && NFSHASONEOPENOWN(nmp) && !NFSHASPNFS(nmp) &&
1334 	    (nmp->nm_privflag & NFSMNTP_DELEGISSUED) == 0 &&
1335 	    (!NFSMNT_RDONLY(mp) || (flags & OPENWRITE) == 0) &&
1336 	    (flags & (ISLASTCN | ISOPEN)) == (ISLASTCN | ISOPEN)) {
1337 		if ((flags & OPENREAD) != 0)
1338 			openmode |= NFSV4OPEN_ACCESSREAD;
1339 		if ((flags & OPENWRITE) != 0)
1340 			openmode |= NFSV4OPEN_ACCESSWRITE;
1341 	}
1342 	NFSUNLOCKMNT(nmp);
1343 
1344 	newvp = NULLVP;
1345 	NFSINCRGLOBAL(nfsstatsv1.lookupcache_misses);
1346 	nanouptime(&ts);
1347 	error = nfsrpc_lookup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
1348 	    cnp->cn_cred, td, &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag,
1349 	    openmode);
1350 	if (dattrflag)
1351 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, 0, 1);
1352 	if (error) {
1353 		if (newvp != NULLVP) {
1354 			vput(newvp);
1355 			*vpp = NULLVP;
1356 		}
1357 
1358 		if (error != ENOENT) {
1359 			if (NFS_ISV4(dvp))
1360 				error = nfscl_maperr(td, error, (uid_t)0,
1361 				    (gid_t)0);
1362 			return (error);
1363 		}
1364 
1365 		/* The requested file was not found. */
1366 		if ((cnp->cn_nameiop == CREATE || cnp->cn_nameiop == RENAME) &&
1367 		    (flags & ISLASTCN)) {
1368 			/*
1369 			 * XXX: UFS does a full VOP_ACCESS(dvp,
1370 			 * VWRITE) here instead of just checking
1371 			 * MNT_RDONLY.
1372 			 */
1373 			if (mp->mnt_flag & MNT_RDONLY)
1374 				return (EROFS);
1375 			cnp->cn_flags |= SAVENAME;
1376 			return (EJUSTRETURN);
1377 		}
1378 
1379 		if ((cnp->cn_flags & MAKEENTRY) != 0 && dattrflag) {
1380 			/*
1381 			 * Cache the modification time of the parent
1382 			 * directory from the post-op attributes in
1383 			 * the name cache entry.  The negative cache
1384 			 * entry will be ignored once the directory
1385 			 * has changed.  Don't bother adding the entry
1386 			 * if the directory has already changed.
1387 			 */
1388 			NFSLOCKNODE(np);
1389 			if (timespeccmp(&np->n_vattr.na_mtime,
1390 			    &dnfsva.na_mtime, ==)) {
1391 				NFSUNLOCKNODE(np);
1392 				cache_enter_time(dvp, NULL, cnp,
1393 				    &dnfsva.na_mtime, NULL);
1394 			} else
1395 				NFSUNLOCKNODE(np);
1396 		}
1397 		return (ENOENT);
1398 	}
1399 
1400 	/*
1401 	 * Handle RENAME case...
1402 	 */
1403 	if (cnp->cn_nameiop == RENAME && (flags & ISLASTCN)) {
1404 		if (NFS_CMPFH(np, nfhp->nfh_fh, nfhp->nfh_len)) {
1405 			free(nfhp, M_NFSFH);
1406 			return (EISDIR);
1407 		}
1408 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np, LK_EXCLUSIVE);
1409 		if (error)
1410 			return (error);
1411 		newvp = NFSTOV(np);
1412 		/*
1413 		 * If n_localmodtime >= time before RPC, then
1414 		 * a file modification operation, such as
1415 		 * VOP_SETATTR() of size, has occurred while
1416 		 * the Lookup RPC and acquisition of the vnode
1417 		 * happened.  As such, the attributes might
1418 		 * be stale, with possibly an incorrect size.
1419 		 */
1420 		NFSLOCKNODE(np);
1421 		if (timespecisset(&np->n_localmodtime) &&
1422 		    timespeccmp(&np->n_localmodtime, &ts, >=)) {
1423 			NFSCL_DEBUG(4, "nfs_lookup: rename localmod "
1424 			    "stale attributes\n");
1425 			attrflag = 0;
1426 		}
1427 		NFSUNLOCKNODE(np);
1428 		if (attrflag)
1429 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, 0, 1);
1430 		*vpp = newvp;
1431 		cnp->cn_flags |= SAVENAME;
1432 		return (0);
1433 	}
1434 
1435 	if (flags & ISDOTDOT) {
1436 		ltype = NFSVOPISLOCKED(dvp);
1437 		error = vfs_busy(mp, MBF_NOWAIT);
1438 		if (error != 0) {
1439 			vfs_ref(mp);
1440 			NFSVOPUNLOCK(dvp);
1441 			error = vfs_busy(mp, 0);
1442 			NFSVOPLOCK(dvp, ltype | LK_RETRY);
1443 			vfs_rel(mp);
1444 			if (error == 0 && VN_IS_DOOMED(dvp)) {
1445 				vfs_unbusy(mp);
1446 				error = ENOENT;
1447 			}
1448 			if (error != 0)
1449 				return (error);
1450 		}
1451 		NFSVOPUNLOCK(dvp);
1452 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np,
1453 		    cnp->cn_lkflags);
1454 		if (error == 0)
1455 			newvp = NFSTOV(np);
1456 		vfs_unbusy(mp);
1457 		if (newvp != dvp)
1458 			NFSVOPLOCK(dvp, ltype | LK_RETRY);
1459 		if (VN_IS_DOOMED(dvp)) {
1460 			if (error == 0) {
1461 				if (newvp == dvp)
1462 					vrele(newvp);
1463 				else
1464 					vput(newvp);
1465 			}
1466 			error = ENOENT;
1467 		}
1468 		if (error != 0)
1469 			return (error);
1470 		if (attrflag)
1471 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, 0, 1);
1472 	} else if (NFS_CMPFH(np, nfhp->nfh_fh, nfhp->nfh_len)) {
1473 		free(nfhp, M_NFSFH);
1474 		VREF(dvp);
1475 		newvp = dvp;
1476 		if (attrflag)
1477 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, 0, 1);
1478 	} else {
1479 		error = nfscl_nget(mp, dvp, nfhp, cnp, td, &np,
1480 		    cnp->cn_lkflags);
1481 		if (error)
1482 			return (error);
1483 		newvp = NFSTOV(np);
1484 		/*
1485 		 * If n_localmodtime >= time before RPC, then
1486 		 * a file modification operation, such as
1487 		 * VOP_SETATTR() of size, has occurred while
1488 		 * the Lookup RPC and acquisition of the vnode
1489 		 * happened.  As such, the attributes might
1490 		 * be stale, with possibly an incorrect size.
1491 		 */
1492 		NFSLOCKNODE(np);
1493 		if (timespecisset(&np->n_localmodtime) &&
1494 		    timespeccmp(&np->n_localmodtime, &ts, >=)) {
1495 			NFSCL_DEBUG(4, "nfs_lookup: localmod "
1496 			    "stale attributes\n");
1497 			attrflag = 0;
1498 		}
1499 		NFSUNLOCKNODE(np);
1500 		if (attrflag)
1501 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, 0, 1);
1502 		else if ((flags & (ISLASTCN | ISOPEN)) == (ISLASTCN | ISOPEN) &&
1503 		    !(np->n_flag & NMODIFIED)) {
1504 			/*
1505 			 * Flush the attribute cache when opening a
1506 			 * leaf node to ensure that fresh attributes
1507 			 * are fetched in nfs_open() since we did not
1508 			 * fetch attributes from the LOOKUP reply.
1509 			 */
1510 			NFSLOCKNODE(np);
1511 			np->n_attrstamp = 0;
1512 			KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(newvp);
1513 			NFSUNLOCKNODE(np);
1514 		}
1515 	}
1516 	if (cnp->cn_nameiop != LOOKUP && (flags & ISLASTCN))
1517 		cnp->cn_flags |= SAVENAME;
1518 	if ((cnp->cn_flags & MAKEENTRY) && dvp != newvp &&
1519 	    (cnp->cn_nameiop != DELETE || !(flags & ISLASTCN)) &&
1520 	    attrflag != 0 && (newvp->v_type != VDIR || dattrflag != 0))
1521 		cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime,
1522 		    newvp->v_type != VDIR ? NULL : &dnfsva.na_ctime);
1523 	*vpp = newvp;
1524 	return (0);
1525 }
1526 
1527 /*
1528  * nfs read call.
1529  * Just call ncl_bioread() to do the work.
1530  */
1531 static int
1532 nfs_read(struct vop_read_args *ap)
1533 {
1534 	struct vnode *vp = ap->a_vp;
1535 
1536 	switch (vp->v_type) {
1537 	case VREG:
1538 		return (ncl_bioread(vp, ap->a_uio, ap->a_ioflag, ap->a_cred));
1539 	case VDIR:
1540 		return (EISDIR);
1541 	default:
1542 		return (EOPNOTSUPP);
1543 	}
1544 }
1545 
1546 /*
1547  * nfs readlink call
1548  */
1549 static int
1550 nfs_readlink(struct vop_readlink_args *ap)
1551 {
1552 	struct vnode *vp = ap->a_vp;
1553 
1554 	if (vp->v_type != VLNK)
1555 		return (EINVAL);
1556 	return (ncl_bioread(vp, ap->a_uio, 0, ap->a_cred));
1557 }
1558 
1559 /*
1560  * Do a readlink rpc.
1561  * Called by ncl_doio() from below the buffer cache.
1562  */
1563 int
1564 ncl_readlinkrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred)
1565 {
1566 	int error, ret, attrflag;
1567 	struct nfsvattr nfsva;
1568 
1569 	error = nfsrpc_readlink(vp, uiop, cred, uiop->uio_td, &nfsva,
1570 	    &attrflag);
1571 	if (attrflag) {
1572 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
1573 		if (ret && !error)
1574 			error = ret;
1575 	}
1576 	if (error && NFS_ISV4(vp))
1577 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1578 	return (error);
1579 }
1580 
1581 /*
1582  * nfs read rpc call
1583  * Ditto above
1584  */
1585 int
1586 ncl_readrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred)
1587 {
1588 	int error, ret, attrflag;
1589 	struct nfsvattr nfsva;
1590 	struct nfsmount *nmp;
1591 
1592 	nmp = VFSTONFS(vp->v_mount);
1593 	error = EIO;
1594 	attrflag = 0;
1595 	if (NFSHASPNFS(nmp))
1596 		error = nfscl_doiods(vp, uiop, NULL, NULL,
1597 		    NFSV4OPEN_ACCESSREAD, 0, cred, uiop->uio_td);
1598 	NFSCL_DEBUG(4, "readrpc: aft doiods=%d\n", error);
1599 	if (error != 0)
1600 		error = nfsrpc_read(vp, uiop, cred, uiop->uio_td, &nfsva,
1601 		    &attrflag);
1602 	if (attrflag) {
1603 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
1604 		if (ret && !error)
1605 			error = ret;
1606 	}
1607 	if (error && NFS_ISV4(vp))
1608 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1609 	return (error);
1610 }
1611 
1612 /*
1613  * nfs write call
1614  */
1615 int
1616 ncl_writerpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
1617     int *iomode, int *must_commit, int called_from_strategy, int ioflag)
1618 {
1619 	struct nfsvattr nfsva;
1620 	int error, attrflag, ret;
1621 	struct nfsmount *nmp;
1622 
1623 	nmp = VFSTONFS(vp->v_mount);
1624 	error = EIO;
1625 	attrflag = 0;
1626 	if (NFSHASPNFS(nmp))
1627 		error = nfscl_doiods(vp, uiop, iomode, must_commit,
1628 		    NFSV4OPEN_ACCESSWRITE, 0, cred, uiop->uio_td);
1629 	NFSCL_DEBUG(4, "writerpc: aft doiods=%d\n", error);
1630 	if (error != 0)
1631 		error = nfsrpc_write(vp, uiop, iomode, must_commit, cred,
1632 		    uiop->uio_td, &nfsva, &attrflag, called_from_strategy,
1633 		    ioflag);
1634 	if (attrflag) {
1635 		if (VTONFS(vp)->n_flag & ND_NFSV4)
1636 			ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 1, 1);
1637 		else
1638 			ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
1639 		if (ret && !error)
1640 			error = ret;
1641 	}
1642 	if (DOINGASYNC(vp))
1643 		*iomode = NFSWRITE_FILESYNC;
1644 	if (error && NFS_ISV4(vp))
1645 		error = nfscl_maperr(uiop->uio_td, error, (uid_t)0, (gid_t)0);
1646 	return (error);
1647 }
1648 
1649 /*
1650  * nfs mknod rpc
1651  * For NFS v2 this is a kludge. Use a create rpc but with the IFMT bits of the
1652  * mode set to specify the file type and the size field for rdev.
1653  */
1654 static int
1655 nfs_mknodrpc(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp,
1656     struct vattr *vap)
1657 {
1658 	struct nfsvattr nfsva, dnfsva;
1659 	struct vnode *newvp = NULL;
1660 	struct nfsnode *np = NULL, *dnp;
1661 	struct nfsfh *nfhp;
1662 	struct vattr vattr;
1663 	int error = 0, attrflag, dattrflag;
1664 	u_int32_t rdev;
1665 
1666 	if (vap->va_type == VCHR || vap->va_type == VBLK)
1667 		rdev = vap->va_rdev;
1668 	else if (vap->va_type == VFIFO || vap->va_type == VSOCK)
1669 		rdev = 0xffffffff;
1670 	else
1671 		return (EOPNOTSUPP);
1672 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)))
1673 		return (error);
1674 	error = nfsrpc_mknod(dvp, cnp->cn_nameptr, cnp->cn_namelen, vap,
1675 	    rdev, vap->va_type, cnp->cn_cred, curthread, &dnfsva,
1676 	    &nfsva, &nfhp, &attrflag, &dattrflag);
1677 	if (!error) {
1678 		if (!nfhp)
1679 			(void) nfsrpc_lookup(dvp, cnp->cn_nameptr,
1680 			    cnp->cn_namelen, cnp->cn_cred, curthread,
1681 			    &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag, 0);
1682 		if (nfhp)
1683 			error = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp,
1684 			    curthread, &np, LK_EXCLUSIVE);
1685 	}
1686 	if (dattrflag)
1687 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, 0, 1);
1688 	if (!error) {
1689 		newvp = NFSTOV(np);
1690 		if (attrflag != 0) {
1691 			error = nfscl_loadattrcache(&newvp, &nfsva, NULL, 0, 1);
1692 			if (error != 0)
1693 				vput(newvp);
1694 		}
1695 	}
1696 	if (!error) {
1697 		*vpp = newvp;
1698 	} else if (NFS_ISV4(dvp)) {
1699 		error = nfscl_maperr(curthread, error, vap->va_uid,
1700 		    vap->va_gid);
1701 	}
1702 	dnp = VTONFS(dvp);
1703 	NFSLOCKNODE(dnp);
1704 	dnp->n_flag |= NMODIFIED;
1705 	if (!dattrflag) {
1706 		dnp->n_attrstamp = 0;
1707 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1708 	}
1709 	NFSUNLOCKNODE(dnp);
1710 	return (error);
1711 }
1712 
1713 /*
1714  * nfs mknod vop
1715  * just call nfs_mknodrpc() to do the work.
1716  */
1717 /* ARGSUSED */
1718 static int
1719 nfs_mknod(struct vop_mknod_args *ap)
1720 {
1721 	return (nfs_mknodrpc(ap->a_dvp, ap->a_vpp, ap->a_cnp, ap->a_vap));
1722 }
1723 
1724 static struct mtx nfs_cverf_mtx;
1725 MTX_SYSINIT(nfs_cverf_mtx, &nfs_cverf_mtx, "NFS create verifier mutex",
1726     MTX_DEF);
1727 
1728 static nfsquad_t
1729 nfs_get_cverf(void)
1730 {
1731 	static nfsquad_t cverf;
1732 	nfsquad_t ret;
1733 	static int cverf_initialized = 0;
1734 
1735 	mtx_lock(&nfs_cverf_mtx);
1736 	if (cverf_initialized == 0) {
1737 		cverf.lval[0] = arc4random();
1738 		cverf.lval[1] = arc4random();
1739 		cverf_initialized = 1;
1740 	} else
1741 		cverf.qval++;
1742 	ret = cverf;
1743 	mtx_unlock(&nfs_cverf_mtx);
1744 
1745 	return (ret);
1746 }
1747 
1748 /*
1749  * nfs file create call
1750  */
1751 static int
1752 nfs_create(struct vop_create_args *ap)
1753 {
1754 	struct vnode *dvp = ap->a_dvp;
1755 	struct vattr *vap = ap->a_vap;
1756 	struct componentname *cnp = ap->a_cnp;
1757 	struct nfsnode *np = NULL, *dnp;
1758 	struct vnode *newvp = NULL;
1759 	struct nfsmount *nmp;
1760 	struct nfsvattr dnfsva, nfsva;
1761 	struct nfsfh *nfhp;
1762 	nfsquad_t cverf;
1763 	int error = 0, attrflag, dattrflag, fmode = 0;
1764 	struct vattr vattr;
1765 
1766 	/*
1767 	 * Oops, not for me..
1768 	 */
1769 	if (vap->va_type == VSOCK)
1770 		return (nfs_mknodrpc(dvp, ap->a_vpp, cnp, vap));
1771 
1772 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)))
1773 		return (error);
1774 	if (vap->va_vaflags & VA_EXCLUSIVE)
1775 		fmode |= O_EXCL;
1776 	dnp = VTONFS(dvp);
1777 	nmp = VFSTONFS(dvp->v_mount);
1778 again:
1779 	/* For NFSv4, wait until any remove is done. */
1780 	NFSLOCKNODE(dnp);
1781 	while (NFSHASNFSV4(nmp) && (dnp->n_flag & NREMOVEINPROG)) {
1782 		dnp->n_flag |= NREMOVEWANT;
1783 		(void) msleep((caddr_t)dnp, &dnp->n_mtx, PZERO, "nfscrt", 0);
1784 	}
1785 	NFSUNLOCKNODE(dnp);
1786 
1787 	cverf = nfs_get_cverf();
1788 	error = nfsrpc_create(dvp, cnp->cn_nameptr, cnp->cn_namelen,
1789 	    vap, cverf, fmode, cnp->cn_cred, curthread, &dnfsva, &nfsva,
1790 	    &nfhp, &attrflag, &dattrflag);
1791 	if (!error) {
1792 		if (nfhp == NULL)
1793 			(void) nfsrpc_lookup(dvp, cnp->cn_nameptr,
1794 			    cnp->cn_namelen, cnp->cn_cred, curthread,
1795 			    &dnfsva, &nfsva, &nfhp, &attrflag, &dattrflag, 0);
1796 		if (nfhp != NULL)
1797 			error = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp,
1798 			    curthread, &np, LK_EXCLUSIVE);
1799 	}
1800 	if (dattrflag)
1801 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, 0, 1);
1802 	if (!error) {
1803 		newvp = NFSTOV(np);
1804 		if (attrflag == 0)
1805 			error = nfsrpc_getattr(newvp, cnp->cn_cred, curthread,
1806 			    &nfsva);
1807 		if (error == 0)
1808 			error = nfscl_loadattrcache(&newvp, &nfsva, NULL, 0, 1);
1809 	}
1810 	if (error) {
1811 		if (newvp != NULL) {
1812 			vput(newvp);
1813 			newvp = NULL;
1814 		}
1815 		if (NFS_ISV34(dvp) && (fmode & O_EXCL) &&
1816 		    error == NFSERR_NOTSUPP) {
1817 			fmode &= ~O_EXCL;
1818 			goto again;
1819 		}
1820 	} else if (NFS_ISV34(dvp) && (fmode & O_EXCL)) {
1821 		if (nfscl_checksattr(vap, &nfsva)) {
1822 			error = nfsrpc_setattr(newvp, vap, NULL, cnp->cn_cred,
1823 			    curthread, &nfsva, &attrflag);
1824 			if (error && (vap->va_uid != (uid_t)VNOVAL ||
1825 			    vap->va_gid != (gid_t)VNOVAL)) {
1826 				/* try again without setting uid/gid */
1827 				vap->va_uid = (uid_t)VNOVAL;
1828 				vap->va_gid = (uid_t)VNOVAL;
1829 				error = nfsrpc_setattr(newvp, vap, NULL,
1830 				    cnp->cn_cred, curthread, &nfsva, &attrflag);
1831 			}
1832 			if (attrflag)
1833 				(void) nfscl_loadattrcache(&newvp, &nfsva, NULL,
1834 				    0, 1);
1835 			if (error != 0)
1836 				vput(newvp);
1837 		}
1838 	}
1839 	if (!error) {
1840 		if ((cnp->cn_flags & MAKEENTRY) && attrflag) {
1841 			if (dvp != newvp)
1842 				cache_enter_time(dvp, newvp, cnp,
1843 				    &nfsva.na_ctime, NULL);
1844 			else
1845 				printf("nfs_create: bogus NFS server returned "
1846 				    "the directory as the new file object\n");
1847 		}
1848 		*ap->a_vpp = newvp;
1849 	} else if (NFS_ISV4(dvp)) {
1850 		error = nfscl_maperr(curthread, error, vap->va_uid,
1851 		    vap->va_gid);
1852 	}
1853 	NFSLOCKNODE(dnp);
1854 	dnp->n_flag |= NMODIFIED;
1855 	if (!dattrflag) {
1856 		dnp->n_attrstamp = 0;
1857 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1858 	}
1859 	NFSUNLOCKNODE(dnp);
1860 	return (error);
1861 }
1862 
1863 /*
1864  * nfs file remove call
1865  * To try and make nfs semantics closer to ufs semantics, a file that has
1866  * other processes using the vnode is renamed instead of removed and then
1867  * removed later on the last close.
1868  * - If v_usecount > 1
1869  *	  If a rename is not already in the works
1870  *	     call nfs_sillyrename() to set it up
1871  *     else
1872  *	  do the remove rpc
1873  */
1874 static int
1875 nfs_remove(struct vop_remove_args *ap)
1876 {
1877 	struct vnode *vp = ap->a_vp;
1878 	struct vnode *dvp = ap->a_dvp;
1879 	struct componentname *cnp = ap->a_cnp;
1880 	struct nfsnode *np = VTONFS(vp);
1881 	int error = 0;
1882 	struct vattr vattr;
1883 
1884 	KASSERT((cnp->cn_flags & HASBUF) != 0, ("nfs_remove: no name"));
1885 	KASSERT(vrefcnt(vp) > 0, ("nfs_remove: bad v_usecount"));
1886 	if (vp->v_type == VDIR)
1887 		error = EPERM;
1888 	else if (vrefcnt(vp) == 1 || (np->n_sillyrename &&
1889 	    VOP_GETATTR(vp, &vattr, cnp->cn_cred) == 0 &&
1890 	    vattr.va_nlink > 1)) {
1891 		/*
1892 		 * Purge the name cache so that the chance of a lookup for
1893 		 * the name succeeding while the remove is in progress is
1894 		 * minimized. Without node locking it can still happen, such
1895 		 * that an I/O op returns ESTALE, but since you get this if
1896 		 * another host removes the file..
1897 		 */
1898 		cache_purge(vp);
1899 		/*
1900 		 * throw away biocache buffers, mainly to avoid
1901 		 * unnecessary delayed writes later.
1902 		 */
1903 		error = ncl_vinvalbuf(vp, 0, curthread, 1);
1904 		if (error != EINTR && error != EIO)
1905 			/* Do the rpc */
1906 			error = nfs_removerpc(dvp, vp, cnp->cn_nameptr,
1907 			    cnp->cn_namelen, cnp->cn_cred, curthread);
1908 		/*
1909 		 * Kludge City: If the first reply to the remove rpc is lost..
1910 		 *   the reply to the retransmitted request will be ENOENT
1911 		 *   since the file was in fact removed
1912 		 *   Therefore, we cheat and return success.
1913 		 */
1914 		if (error == ENOENT)
1915 			error = 0;
1916 	} else if (!np->n_sillyrename)
1917 		error = nfs_sillyrename(dvp, vp, cnp);
1918 	NFSLOCKNODE(np);
1919 	np->n_attrstamp = 0;
1920 	NFSUNLOCKNODE(np);
1921 	KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
1922 	return (error);
1923 }
1924 
1925 /*
1926  * nfs file remove rpc called from nfs_inactive
1927  */
1928 int
1929 ncl_removeit(struct sillyrename *sp, struct vnode *vp)
1930 {
1931 	/*
1932 	 * Make sure that the directory vnode is still valid.
1933 	 * XXX we should lock sp->s_dvp here.
1934 	 */
1935 	if (sp->s_dvp->v_type == VBAD)
1936 		return (0);
1937 	return (nfs_removerpc(sp->s_dvp, vp, sp->s_name, sp->s_namlen,
1938 	    sp->s_cred, NULL));
1939 }
1940 
1941 /*
1942  * Nfs remove rpc, called from nfs_remove() and ncl_removeit().
1943  */
1944 static int
1945 nfs_removerpc(struct vnode *dvp, struct vnode *vp, char *name,
1946     int namelen, struct ucred *cred, struct thread *td)
1947 {
1948 	struct nfsvattr dnfsva;
1949 	struct nfsnode *dnp = VTONFS(dvp);
1950 	int error = 0, dattrflag;
1951 
1952 	NFSLOCKNODE(dnp);
1953 	dnp->n_flag |= NREMOVEINPROG;
1954 	NFSUNLOCKNODE(dnp);
1955 	error = nfsrpc_remove(dvp, name, namelen, vp, cred, td, &dnfsva,
1956 	    &dattrflag);
1957 	NFSLOCKNODE(dnp);
1958 	if ((dnp->n_flag & NREMOVEWANT)) {
1959 		dnp->n_flag &= ~(NREMOVEWANT | NREMOVEINPROG);
1960 		NFSUNLOCKNODE(dnp);
1961 		wakeup((caddr_t)dnp);
1962 	} else {
1963 		dnp->n_flag &= ~NREMOVEINPROG;
1964 		NFSUNLOCKNODE(dnp);
1965 	}
1966 	if (dattrflag)
1967 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, 0, 1);
1968 	NFSLOCKNODE(dnp);
1969 	dnp->n_flag |= NMODIFIED;
1970 	if (!dattrflag) {
1971 		dnp->n_attrstamp = 0;
1972 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
1973 	}
1974 	NFSUNLOCKNODE(dnp);
1975 	if (error && NFS_ISV4(dvp))
1976 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
1977 	return (error);
1978 }
1979 
1980 /*
1981  * nfs file rename call
1982  */
1983 static int
1984 nfs_rename(struct vop_rename_args *ap)
1985 {
1986 	struct vnode *fvp = ap->a_fvp;
1987 	struct vnode *tvp = ap->a_tvp;
1988 	struct vnode *fdvp = ap->a_fdvp;
1989 	struct vnode *tdvp = ap->a_tdvp;
1990 	struct componentname *tcnp = ap->a_tcnp;
1991 	struct componentname *fcnp = ap->a_fcnp;
1992 	struct nfsnode *fnp = VTONFS(ap->a_fvp);
1993 	struct nfsnode *tdnp = VTONFS(ap->a_tdvp);
1994 	struct nfsv4node *newv4 = NULL;
1995 	int error;
1996 
1997 	KASSERT((tcnp->cn_flags & HASBUF) != 0 &&
1998 	    (fcnp->cn_flags & HASBUF) != 0, ("nfs_rename: no name"));
1999 	/* Check for cross-device rename */
2000 	if ((fvp->v_mount != tdvp->v_mount) ||
2001 	    (tvp && (fvp->v_mount != tvp->v_mount))) {
2002 		error = EXDEV;
2003 		goto out;
2004 	}
2005 
2006 	if (fvp == tvp) {
2007 		printf("nfs_rename: fvp == tvp (can't happen)\n");
2008 		error = 0;
2009 		goto out;
2010 	}
2011 	if ((error = NFSVOPLOCK(fvp, LK_EXCLUSIVE)) != 0)
2012 		goto out;
2013 
2014 	/*
2015 	 * We have to flush B_DELWRI data prior to renaming
2016 	 * the file.  If we don't, the delayed-write buffers
2017 	 * can be flushed out later after the file has gone stale
2018 	 * under NFSV3.  NFSV2 does not have this problem because
2019 	 * ( as far as I can tell ) it flushes dirty buffers more
2020 	 * often.
2021 	 *
2022 	 * Skip the rename operation if the fsync fails, this can happen
2023 	 * due to the server's volume being full, when we pushed out data
2024 	 * that was written back to our cache earlier. Not checking for
2025 	 * this condition can result in potential (silent) data loss.
2026 	 */
2027 	error = VOP_FSYNC(fvp, MNT_WAIT, curthread);
2028 	NFSVOPUNLOCK(fvp);
2029 	if (!error && tvp)
2030 		error = VOP_FSYNC(tvp, MNT_WAIT, curthread);
2031 	if (error)
2032 		goto out;
2033 
2034 	/*
2035 	 * If the tvp exists and is in use, sillyrename it before doing the
2036 	 * rename of the new file over it.
2037 	 * XXX Can't sillyrename a directory.
2038 	 */
2039 	if (tvp && vrefcnt(tvp) > 1 && !VTONFS(tvp)->n_sillyrename &&
2040 		tvp->v_type != VDIR && !nfs_sillyrename(tdvp, tvp, tcnp)) {
2041 		vput(tvp);
2042 		tvp = NULL;
2043 	}
2044 
2045 	error = nfs_renamerpc(fdvp, fvp, fcnp->cn_nameptr, fcnp->cn_namelen,
2046 	    tdvp, tvp, tcnp->cn_nameptr, tcnp->cn_namelen, tcnp->cn_cred,
2047 	    curthread);
2048 
2049 	if (error == 0 && NFS_ISV4(tdvp)) {
2050 		/*
2051 		 * For NFSv4, check to see if it is the same name and
2052 		 * replace the name, if it is different.
2053 		 */
2054 		newv4 = malloc(
2055 		    sizeof (struct nfsv4node) +
2056 		    tdnp->n_fhp->nfh_len + tcnp->cn_namelen - 1,
2057 		    M_NFSV4NODE, M_WAITOK);
2058 		NFSLOCKNODE(tdnp);
2059 		NFSLOCKNODE(fnp);
2060 		if (fnp->n_v4 != NULL && fvp->v_type == VREG &&
2061 		    (fnp->n_v4->n4_namelen != tcnp->cn_namelen ||
2062 		      NFSBCMP(tcnp->cn_nameptr, NFS4NODENAME(fnp->n_v4),
2063 		      tcnp->cn_namelen) ||
2064 		      tdnp->n_fhp->nfh_len != fnp->n_v4->n4_fhlen ||
2065 		      NFSBCMP(tdnp->n_fhp->nfh_fh, fnp->n_v4->n4_data,
2066 			tdnp->n_fhp->nfh_len))) {
2067 #ifdef notdef
2068 { char nnn[100]; int nnnl;
2069 nnnl = (tcnp->cn_namelen < 100) ? tcnp->cn_namelen : 99;
2070 bcopy(tcnp->cn_nameptr, nnn, nnnl);
2071 nnn[nnnl] = '\0';
2072 printf("ren replace=%s\n",nnn);
2073 }
2074 #endif
2075 			free(fnp->n_v4, M_NFSV4NODE);
2076 			fnp->n_v4 = newv4;
2077 			newv4 = NULL;
2078 			fnp->n_v4->n4_fhlen = tdnp->n_fhp->nfh_len;
2079 			fnp->n_v4->n4_namelen = tcnp->cn_namelen;
2080 			NFSBCOPY(tdnp->n_fhp->nfh_fh, fnp->n_v4->n4_data,
2081 			    tdnp->n_fhp->nfh_len);
2082 			NFSBCOPY(tcnp->cn_nameptr,
2083 			    NFS4NODENAME(fnp->n_v4), tcnp->cn_namelen);
2084 		}
2085 		NFSUNLOCKNODE(tdnp);
2086 		NFSUNLOCKNODE(fnp);
2087 		if (newv4 != NULL)
2088 			free(newv4, M_NFSV4NODE);
2089 	}
2090 
2091 	if (fvp->v_type == VDIR) {
2092 		if (tvp != NULL && tvp->v_type == VDIR)
2093 			cache_purge(tdvp);
2094 		cache_purge(fdvp);
2095 	}
2096 
2097 out:
2098 	if (tdvp == tvp)
2099 		vrele(tdvp);
2100 	else
2101 		vput(tdvp);
2102 	if (tvp)
2103 		vput(tvp);
2104 	vrele(fdvp);
2105 	vrele(fvp);
2106 	/*
2107 	 * Kludge: Map ENOENT => 0 assuming that it is a reply to a retry.
2108 	 */
2109 	if (error == ENOENT)
2110 		error = 0;
2111 	return (error);
2112 }
2113 
2114 /*
2115  * nfs file rename rpc called from nfs_remove() above
2116  */
2117 static int
2118 nfs_renameit(struct vnode *sdvp, struct vnode *svp, struct componentname *scnp,
2119     struct sillyrename *sp)
2120 {
2121 
2122 	return (nfs_renamerpc(sdvp, svp, scnp->cn_nameptr, scnp->cn_namelen,
2123 	    sdvp, NULL, sp->s_name, sp->s_namlen, scnp->cn_cred,
2124 	    curthread));
2125 }
2126 
2127 /*
2128  * Do an nfs rename rpc. Called from nfs_rename() and nfs_renameit().
2129  */
2130 static int
2131 nfs_renamerpc(struct vnode *fdvp, struct vnode *fvp, char *fnameptr,
2132     int fnamelen, struct vnode *tdvp, struct vnode *tvp, char *tnameptr,
2133     int tnamelen, struct ucred *cred, struct thread *td)
2134 {
2135 	struct nfsvattr fnfsva, tnfsva;
2136 	struct nfsnode *fdnp = VTONFS(fdvp);
2137 	struct nfsnode *tdnp = VTONFS(tdvp);
2138 	int error = 0, fattrflag, tattrflag;
2139 
2140 	error = nfsrpc_rename(fdvp, fvp, fnameptr, fnamelen, tdvp, tvp,
2141 	    tnameptr, tnamelen, cred, td, &fnfsva, &tnfsva, &fattrflag,
2142 	    &tattrflag);
2143 	NFSLOCKNODE(fdnp);
2144 	fdnp->n_flag |= NMODIFIED;
2145 	if (fattrflag != 0) {
2146 		NFSUNLOCKNODE(fdnp);
2147 		(void) nfscl_loadattrcache(&fdvp, &fnfsva, NULL, 0, 1);
2148 	} else {
2149 		fdnp->n_attrstamp = 0;
2150 		NFSUNLOCKNODE(fdnp);
2151 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(fdvp);
2152 	}
2153 	NFSLOCKNODE(tdnp);
2154 	tdnp->n_flag |= NMODIFIED;
2155 	if (tattrflag != 0) {
2156 		NFSUNLOCKNODE(tdnp);
2157 		(void) nfscl_loadattrcache(&tdvp, &tnfsva, NULL, 0, 1);
2158 	} else {
2159 		tdnp->n_attrstamp = 0;
2160 		NFSUNLOCKNODE(tdnp);
2161 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(tdvp);
2162 	}
2163 	if (error && NFS_ISV4(fdvp))
2164 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2165 	return (error);
2166 }
2167 
2168 /*
2169  * nfs hard link create call
2170  */
2171 static int
2172 nfs_link(struct vop_link_args *ap)
2173 {
2174 	struct vnode *vp = ap->a_vp;
2175 	struct vnode *tdvp = ap->a_tdvp;
2176 	struct componentname *cnp = ap->a_cnp;
2177 	struct nfsnode *np, *tdnp;
2178 	struct nfsvattr nfsva, dnfsva;
2179 	int error = 0, attrflag, dattrflag;
2180 
2181 	/*
2182 	 * Push all writes to the server, so that the attribute cache
2183 	 * doesn't get "out of sync" with the server.
2184 	 * XXX There should be a better way!
2185 	 */
2186 	VOP_FSYNC(vp, MNT_WAIT, curthread);
2187 
2188 	error = nfsrpc_link(tdvp, vp, cnp->cn_nameptr, cnp->cn_namelen,
2189 	    cnp->cn_cred, curthread, &dnfsva, &nfsva, &attrflag, &dattrflag);
2190 	tdnp = VTONFS(tdvp);
2191 	NFSLOCKNODE(tdnp);
2192 	tdnp->n_flag |= NMODIFIED;
2193 	if (dattrflag != 0) {
2194 		NFSUNLOCKNODE(tdnp);
2195 		(void) nfscl_loadattrcache(&tdvp, &dnfsva, NULL, 0, 1);
2196 	} else {
2197 		tdnp->n_attrstamp = 0;
2198 		NFSUNLOCKNODE(tdnp);
2199 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(tdvp);
2200 	}
2201 	if (attrflag)
2202 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
2203 	else {
2204 		np = VTONFS(vp);
2205 		NFSLOCKNODE(np);
2206 		np->n_attrstamp = 0;
2207 		NFSUNLOCKNODE(np);
2208 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
2209 	}
2210 	/*
2211 	 * If negative lookup caching is enabled, I might as well
2212 	 * add an entry for this node. Not necessary for correctness,
2213 	 * but if negative caching is enabled, then the system
2214 	 * must care about lookup caching hit rate, so...
2215 	 */
2216 	if (VFSTONFS(vp->v_mount)->nm_negnametimeo != 0 &&
2217 	    (cnp->cn_flags & MAKEENTRY) && attrflag != 0 && error == 0) {
2218 		if (tdvp != vp)
2219 			cache_enter_time(tdvp, vp, cnp, &nfsva.na_ctime, NULL);
2220 		else
2221 			printf("nfs_link: bogus NFS server returned "
2222 			    "the directory as the new link\n");
2223 	}
2224 	if (error && NFS_ISV4(vp))
2225 		error = nfscl_maperr(curthread, error, (uid_t)0,
2226 		    (gid_t)0);
2227 	return (error);
2228 }
2229 
2230 /*
2231  * nfs symbolic link create call
2232  */
2233 static int
2234 nfs_symlink(struct vop_symlink_args *ap)
2235 {
2236 	struct vnode *dvp = ap->a_dvp;
2237 	struct vattr *vap = ap->a_vap;
2238 	struct componentname *cnp = ap->a_cnp;
2239 	struct nfsvattr nfsva, dnfsva;
2240 	struct nfsfh *nfhp;
2241 	struct nfsnode *np = NULL, *dnp;
2242 	struct vnode *newvp = NULL;
2243 	int error = 0, attrflag, dattrflag, ret;
2244 
2245 	vap->va_type = VLNK;
2246 	error = nfsrpc_symlink(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2247 	    ap->a_target, vap, cnp->cn_cred, curthread, &dnfsva,
2248 	    &nfsva, &nfhp, &attrflag, &dattrflag);
2249 	if (nfhp) {
2250 		ret = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp, curthread,
2251 		    &np, LK_EXCLUSIVE);
2252 		if (!ret)
2253 			newvp = NFSTOV(np);
2254 		else if (!error)
2255 			error = ret;
2256 	}
2257 	if (newvp != NULL) {
2258 		if (attrflag)
2259 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, 0, 1);
2260 	} else if (!error) {
2261 		/*
2262 		 * If we do not have an error and we could not extract the
2263 		 * newvp from the response due to the request being NFSv2, we
2264 		 * have to do a lookup in order to obtain a newvp to return.
2265 		 */
2266 		error = nfs_lookitup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2267 		    cnp->cn_cred, curthread, &np);
2268 		if (!error)
2269 			newvp = NFSTOV(np);
2270 	}
2271 	if (error) {
2272 		if (newvp)
2273 			vput(newvp);
2274 		if (NFS_ISV4(dvp))
2275 			error = nfscl_maperr(curthread, error,
2276 			    vap->va_uid, vap->va_gid);
2277 	} else {
2278 		*ap->a_vpp = newvp;
2279 	}
2280 
2281 	dnp = VTONFS(dvp);
2282 	NFSLOCKNODE(dnp);
2283 	dnp->n_flag |= NMODIFIED;
2284 	if (dattrflag != 0) {
2285 		NFSUNLOCKNODE(dnp);
2286 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, 0, 1);
2287 	} else {
2288 		dnp->n_attrstamp = 0;
2289 		NFSUNLOCKNODE(dnp);
2290 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2291 	}
2292 	/*
2293 	 * If negative lookup caching is enabled, I might as well
2294 	 * add an entry for this node. Not necessary for correctness,
2295 	 * but if negative caching is enabled, then the system
2296 	 * must care about lookup caching hit rate, so...
2297 	 */
2298 	if (VFSTONFS(dvp->v_mount)->nm_negnametimeo != 0 &&
2299 	    (cnp->cn_flags & MAKEENTRY) && attrflag != 0 && error == 0) {
2300 		if (dvp != newvp)
2301 			cache_enter_time(dvp, newvp, cnp, &nfsva.na_ctime,
2302 			    NULL);
2303 		else
2304 			printf("nfs_symlink: bogus NFS server returned "
2305 			    "the directory as the new file object\n");
2306 	}
2307 	return (error);
2308 }
2309 
2310 /*
2311  * nfs make dir call
2312  */
2313 static int
2314 nfs_mkdir(struct vop_mkdir_args *ap)
2315 {
2316 	struct vnode *dvp = ap->a_dvp;
2317 	struct vattr *vap = ap->a_vap;
2318 	struct componentname *cnp = ap->a_cnp;
2319 	struct nfsnode *np = NULL, *dnp;
2320 	struct vnode *newvp = NULL;
2321 	struct vattr vattr;
2322 	struct nfsfh *nfhp;
2323 	struct nfsvattr nfsva, dnfsva;
2324 	int error = 0, attrflag, dattrflag, ret;
2325 
2326 	if ((error = VOP_GETATTR(dvp, &vattr, cnp->cn_cred)) != 0)
2327 		return (error);
2328 	vap->va_type = VDIR;
2329 	error = nfsrpc_mkdir(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2330 	    vap, cnp->cn_cred, curthread, &dnfsva, &nfsva, &nfhp,
2331 	    &attrflag, &dattrflag);
2332 	dnp = VTONFS(dvp);
2333 	NFSLOCKNODE(dnp);
2334 	dnp->n_flag |= NMODIFIED;
2335 	if (dattrflag != 0) {
2336 		NFSUNLOCKNODE(dnp);
2337 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, 0, 1);
2338 	} else {
2339 		dnp->n_attrstamp = 0;
2340 		NFSUNLOCKNODE(dnp);
2341 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2342 	}
2343 	if (nfhp) {
2344 		ret = nfscl_nget(dvp->v_mount, dvp, nfhp, cnp, curthread,
2345 		    &np, LK_EXCLUSIVE);
2346 		if (!ret) {
2347 			newvp = NFSTOV(np);
2348 			if (attrflag)
2349 			   (void) nfscl_loadattrcache(&newvp, &nfsva, NULL,
2350 				0, 1);
2351 		} else if (!error)
2352 			error = ret;
2353 	}
2354 	if (!error && newvp == NULL) {
2355 		error = nfs_lookitup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2356 		    cnp->cn_cred, curthread, &np);
2357 		if (!error) {
2358 			newvp = NFSTOV(np);
2359 			if (newvp->v_type != VDIR)
2360 				error = EEXIST;
2361 		}
2362 	}
2363 	if (error) {
2364 		if (newvp)
2365 			vput(newvp);
2366 		if (NFS_ISV4(dvp))
2367 			error = nfscl_maperr(curthread, error,
2368 			    vap->va_uid, vap->va_gid);
2369 	} else {
2370 		/*
2371 		 * If negative lookup caching is enabled, I might as well
2372 		 * add an entry for this node. Not necessary for correctness,
2373 		 * but if negative caching is enabled, then the system
2374 		 * must care about lookup caching hit rate, so...
2375 		 */
2376 		if (VFSTONFS(dvp->v_mount)->nm_negnametimeo != 0 &&
2377 		    (cnp->cn_flags & MAKEENTRY) &&
2378 		    attrflag != 0 && dattrflag != 0) {
2379 			if (dvp != newvp)
2380 				cache_enter_time(dvp, newvp, cnp,
2381 				    &nfsva.na_ctime, &dnfsva.na_ctime);
2382 			else
2383 				printf("nfs_mkdir: bogus NFS server returned "
2384 				    "the directory that the directory was "
2385 				    "created in as the new file object\n");
2386 		}
2387 		*ap->a_vpp = newvp;
2388 	}
2389 	return (error);
2390 }
2391 
2392 /*
2393  * nfs remove directory call
2394  */
2395 static int
2396 nfs_rmdir(struct vop_rmdir_args *ap)
2397 {
2398 	struct vnode *vp = ap->a_vp;
2399 	struct vnode *dvp = ap->a_dvp;
2400 	struct componentname *cnp = ap->a_cnp;
2401 	struct nfsnode *dnp;
2402 	struct nfsvattr dnfsva;
2403 	int error, dattrflag;
2404 
2405 	if (dvp == vp)
2406 		return (EINVAL);
2407 	error = nfsrpc_rmdir(dvp, cnp->cn_nameptr, cnp->cn_namelen,
2408 	    cnp->cn_cred, curthread, &dnfsva, &dattrflag);
2409 	dnp = VTONFS(dvp);
2410 	NFSLOCKNODE(dnp);
2411 	dnp->n_flag |= NMODIFIED;
2412 	if (dattrflag != 0) {
2413 		NFSUNLOCKNODE(dnp);
2414 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, 0, 1);
2415 	} else {
2416 		dnp->n_attrstamp = 0;
2417 		NFSUNLOCKNODE(dnp);
2418 		KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(dvp);
2419 	}
2420 
2421 	cache_purge(dvp);
2422 	cache_purge(vp);
2423 	if (error && NFS_ISV4(dvp))
2424 		error = nfscl_maperr(curthread, error, (uid_t)0,
2425 		    (gid_t)0);
2426 	/*
2427 	 * Kludge: Map ENOENT => 0 assuming that you have a reply to a retry.
2428 	 */
2429 	if (error == ENOENT)
2430 		error = 0;
2431 	return (error);
2432 }
2433 
2434 /*
2435  * nfs readdir call
2436  */
2437 static int
2438 nfs_readdir(struct vop_readdir_args *ap)
2439 {
2440 	struct vnode *vp = ap->a_vp;
2441 	struct nfsnode *np = VTONFS(vp);
2442 	struct uio *uio = ap->a_uio;
2443 	ssize_t tresid, left;
2444 	int error = 0;
2445 	struct vattr vattr;
2446 
2447 	if (ap->a_eofflag != NULL)
2448 		*ap->a_eofflag = 0;
2449 	if (vp->v_type != VDIR)
2450 		return(EPERM);
2451 
2452 	/*
2453 	 * First, check for hit on the EOF offset cache
2454 	 */
2455 	NFSLOCKNODE(np);
2456 	if (np->n_direofoffset > 0 && uio->uio_offset >= np->n_direofoffset &&
2457 	    (np->n_flag & NMODIFIED) == 0) {
2458 		NFSUNLOCKNODE(np);
2459 		if (VOP_GETATTR(vp, &vattr, ap->a_cred) == 0) {
2460 			NFSLOCKNODE(np);
2461 			if ((NFS_ISV4(vp) && np->n_change == vattr.va_filerev) ||
2462 			    !NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime)) {
2463 				NFSUNLOCKNODE(np);
2464 				NFSINCRGLOBAL(nfsstatsv1.direofcache_hits);
2465 				if (ap->a_eofflag != NULL)
2466 					*ap->a_eofflag = 1;
2467 				return (0);
2468 			} else
2469 				NFSUNLOCKNODE(np);
2470 		}
2471 	} else
2472 		NFSUNLOCKNODE(np);
2473 
2474 	/*
2475 	 * NFS always guarantees that directory entries don't straddle
2476 	 * DIRBLKSIZ boundaries.  As such, we need to limit the size
2477 	 * to an exact multiple of DIRBLKSIZ, to avoid copying a partial
2478 	 * directory entry.
2479 	 */
2480 	left = uio->uio_resid % DIRBLKSIZ;
2481 	if (left == uio->uio_resid)
2482 		return (EINVAL);
2483 	uio->uio_resid -= left;
2484 
2485 	/*
2486 	 * Call ncl_bioread() to do the real work.
2487 	 */
2488 	tresid = uio->uio_resid;
2489 	error = ncl_bioread(vp, uio, 0, ap->a_cred);
2490 
2491 	if (!error && uio->uio_resid == tresid) {
2492 		NFSINCRGLOBAL(nfsstatsv1.direofcache_misses);
2493 		if (ap->a_eofflag != NULL)
2494 			*ap->a_eofflag = 1;
2495 	}
2496 
2497 	/* Add the partial DIRBLKSIZ (left) back in. */
2498 	uio->uio_resid += left;
2499 	return (error);
2500 }
2501 
2502 /*
2503  * Readdir rpc call.
2504  * Called from below the buffer cache by ncl_doio().
2505  */
2506 int
2507 ncl_readdirrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
2508     struct thread *td)
2509 {
2510 	struct nfsvattr nfsva;
2511 	nfsuint64 *cookiep, cookie;
2512 	struct nfsnode *dnp = VTONFS(vp);
2513 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2514 	int error = 0, eof, attrflag;
2515 
2516 	KASSERT(uiop->uio_iovcnt == 1 &&
2517 	    (uiop->uio_offset & (DIRBLKSIZ - 1)) == 0 &&
2518 	    (uiop->uio_resid & (DIRBLKSIZ - 1)) == 0,
2519 	    ("nfs readdirrpc bad uio"));
2520 
2521 	/*
2522 	 * If there is no cookie, assume directory was stale.
2523 	 */
2524 	ncl_dircookie_lock(dnp);
2525 	NFSUNLOCKNODE(dnp);
2526 	cookiep = ncl_getcookie(dnp, uiop->uio_offset, 0);
2527 	if (cookiep) {
2528 		cookie = *cookiep;
2529 		ncl_dircookie_unlock(dnp);
2530 	} else {
2531 		ncl_dircookie_unlock(dnp);
2532 		return (NFSERR_BAD_COOKIE);
2533 	}
2534 
2535 	if (NFSHASNFSV3(nmp) && !NFSHASGOTFSINFO(nmp))
2536 		(void)ncl_fsinfo(nmp, vp, cred, td);
2537 
2538 	error = nfsrpc_readdir(vp, uiop, &cookie, cred, td, &nfsva,
2539 	    &attrflag, &eof);
2540 	if (attrflag)
2541 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
2542 
2543 	if (!error) {
2544 		/*
2545 		 * We are now either at the end of the directory or have filled
2546 		 * the block.
2547 		 */
2548 		if (eof) {
2549 			NFSLOCKNODE(dnp);
2550 			dnp->n_direofoffset = uiop->uio_offset;
2551 			NFSUNLOCKNODE(dnp);
2552 		} else {
2553 			if (uiop->uio_resid > 0)
2554 				printf("EEK! readdirrpc resid > 0\n");
2555 			ncl_dircookie_lock(dnp);
2556 			NFSUNLOCKNODE(dnp);
2557 			cookiep = ncl_getcookie(dnp, uiop->uio_offset, 1);
2558 			*cookiep = cookie;
2559 			ncl_dircookie_unlock(dnp);
2560 		}
2561 	} else if (NFS_ISV4(vp)) {
2562 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2563 	}
2564 	return (error);
2565 }
2566 
2567 /*
2568  * NFS V3 readdir plus RPC. Used in place of ncl_readdirrpc().
2569  */
2570 int
2571 ncl_readdirplusrpc(struct vnode *vp, struct uio *uiop, struct ucred *cred,
2572     struct thread *td)
2573 {
2574 	struct nfsvattr nfsva;
2575 	nfsuint64 *cookiep, cookie;
2576 	struct nfsnode *dnp = VTONFS(vp);
2577 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2578 	int error = 0, attrflag, eof;
2579 
2580 	KASSERT(uiop->uio_iovcnt == 1 &&
2581 	    (uiop->uio_offset & (DIRBLKSIZ - 1)) == 0 &&
2582 	    (uiop->uio_resid & (DIRBLKSIZ - 1)) == 0,
2583 	    ("nfs readdirplusrpc bad uio"));
2584 
2585 	/*
2586 	 * If there is no cookie, assume directory was stale.
2587 	 */
2588 	ncl_dircookie_lock(dnp);
2589 	NFSUNLOCKNODE(dnp);
2590 	cookiep = ncl_getcookie(dnp, uiop->uio_offset, 0);
2591 	if (cookiep) {
2592 		cookie = *cookiep;
2593 		ncl_dircookie_unlock(dnp);
2594 	} else {
2595 		ncl_dircookie_unlock(dnp);
2596 		return (NFSERR_BAD_COOKIE);
2597 	}
2598 
2599 	if (NFSHASNFSV3(nmp) && !NFSHASGOTFSINFO(nmp))
2600 		(void)ncl_fsinfo(nmp, vp, cred, td);
2601 	error = nfsrpc_readdirplus(vp, uiop, &cookie, cred, td, &nfsva,
2602 	    &attrflag, &eof);
2603 	if (attrflag)
2604 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
2605 
2606 	if (!error) {
2607 		/*
2608 		 * We are now either at end of the directory or have filled the
2609 		 * the block.
2610 		 */
2611 		if (eof) {
2612 			NFSLOCKNODE(dnp);
2613 			dnp->n_direofoffset = uiop->uio_offset;
2614 			NFSUNLOCKNODE(dnp);
2615 		} else {
2616 			if (uiop->uio_resid > 0)
2617 				printf("EEK! readdirplusrpc resid > 0\n");
2618 			ncl_dircookie_lock(dnp);
2619 			NFSUNLOCKNODE(dnp);
2620 			cookiep = ncl_getcookie(dnp, uiop->uio_offset, 1);
2621 			*cookiep = cookie;
2622 			ncl_dircookie_unlock(dnp);
2623 		}
2624 	} else if (NFS_ISV4(vp)) {
2625 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2626 	}
2627 	return (error);
2628 }
2629 
2630 /*
2631  * Silly rename. To make the NFS filesystem that is stateless look a little
2632  * more like the "ufs" a remove of an active vnode is translated to a rename
2633  * to a funny looking filename that is removed by nfs_inactive on the
2634  * nfsnode. There is the potential for another process on a different client
2635  * to create the same funny name between the nfs_lookitup() fails and the
2636  * nfs_rename() completes, but...
2637  */
2638 static int
2639 nfs_sillyrename(struct vnode *dvp, struct vnode *vp, struct componentname *cnp)
2640 {
2641 	struct sillyrename *sp;
2642 	struct nfsnode *np;
2643 	int error;
2644 	short pid;
2645 	unsigned int lticks;
2646 
2647 	cache_purge(dvp);
2648 	np = VTONFS(vp);
2649 	KASSERT(vp->v_type != VDIR, ("nfs: sillyrename dir"));
2650 	sp = malloc(sizeof (struct sillyrename),
2651 	    M_NEWNFSREQ, M_WAITOK);
2652 	sp->s_cred = crhold(cnp->cn_cred);
2653 	sp->s_dvp = dvp;
2654 	VREF(dvp);
2655 
2656 	/*
2657 	 * Fudge together a funny name.
2658 	 * Changing the format of the funny name to accommodate more
2659 	 * sillynames per directory.
2660 	 * The name is now changed to .nfs.<ticks>.<pid>.4, where ticks is
2661 	 * CPU ticks since boot.
2662 	 */
2663 	pid = curthread->td_proc->p_pid;
2664 	lticks = (unsigned int)ticks;
2665 	for ( ; ; ) {
2666 		sp->s_namlen = sprintf(sp->s_name,
2667 				       ".nfs.%08x.%04x4.4", lticks,
2668 				       pid);
2669 		if (nfs_lookitup(dvp, sp->s_name, sp->s_namlen, sp->s_cred,
2670 				 curthread, NULL))
2671 			break;
2672 		lticks++;
2673 	}
2674 	error = nfs_renameit(dvp, vp, cnp, sp);
2675 	if (error)
2676 		goto bad;
2677 	error = nfs_lookitup(dvp, sp->s_name, sp->s_namlen, sp->s_cred,
2678 		curthread, &np);
2679 	np->n_sillyrename = sp;
2680 	return (0);
2681 bad:
2682 	vrele(sp->s_dvp);
2683 	crfree(sp->s_cred);
2684 	free(sp, M_NEWNFSREQ);
2685 	return (error);
2686 }
2687 
2688 /*
2689  * Look up a file name and optionally either update the file handle or
2690  * allocate an nfsnode, depending on the value of npp.
2691  * npp == NULL	--> just do the lookup
2692  * *npp == NULL --> allocate a new nfsnode and make sure attributes are
2693  *			handled too
2694  * *npp != NULL --> update the file handle in the vnode
2695  */
2696 static int
2697 nfs_lookitup(struct vnode *dvp, char *name, int len, struct ucred *cred,
2698     struct thread *td, struct nfsnode **npp)
2699 {
2700 	struct vnode *newvp = NULL, *vp;
2701 	struct nfsnode *np, *dnp = VTONFS(dvp);
2702 	struct nfsfh *nfhp, *onfhp;
2703 	struct nfsvattr nfsva, dnfsva;
2704 	struct componentname cn;
2705 	int error = 0, attrflag, dattrflag;
2706 	u_int hash;
2707 	struct timespec ts;
2708 
2709 	nanouptime(&ts);
2710 	error = nfsrpc_lookup(dvp, name, len, cred, td, &dnfsva, &nfsva,
2711 	    &nfhp, &attrflag, &dattrflag, 0);
2712 	if (dattrflag)
2713 		(void) nfscl_loadattrcache(&dvp, &dnfsva, NULL, 0, 1);
2714 	if (npp && !error) {
2715 		if (*npp != NULL) {
2716 		    np = *npp;
2717 		    vp = NFSTOV(np);
2718 		    /*
2719 		     * For NFSv4, check to see if it is the same name and
2720 		     * replace the name, if it is different.
2721 		     */
2722 		    if (np->n_v4 != NULL && nfsva.na_type == VREG &&
2723 			(np->n_v4->n4_namelen != len ||
2724 			 NFSBCMP(name, NFS4NODENAME(np->n_v4), len) ||
2725 			 dnp->n_fhp->nfh_len != np->n_v4->n4_fhlen ||
2726 			 NFSBCMP(dnp->n_fhp->nfh_fh, np->n_v4->n4_data,
2727 			 dnp->n_fhp->nfh_len))) {
2728 #ifdef notdef
2729 { char nnn[100]; int nnnl;
2730 nnnl = (len < 100) ? len : 99;
2731 bcopy(name, nnn, nnnl);
2732 nnn[nnnl] = '\0';
2733 printf("replace=%s\n",nnn);
2734 }
2735 #endif
2736 			    free(np->n_v4, M_NFSV4NODE);
2737 			    np->n_v4 = malloc(
2738 				sizeof (struct nfsv4node) +
2739 				dnp->n_fhp->nfh_len + len - 1,
2740 				M_NFSV4NODE, M_WAITOK);
2741 			    np->n_v4->n4_fhlen = dnp->n_fhp->nfh_len;
2742 			    np->n_v4->n4_namelen = len;
2743 			    NFSBCOPY(dnp->n_fhp->nfh_fh, np->n_v4->n4_data,
2744 				dnp->n_fhp->nfh_len);
2745 			    NFSBCOPY(name, NFS4NODENAME(np->n_v4), len);
2746 		    }
2747 		    hash = fnv_32_buf(nfhp->nfh_fh, nfhp->nfh_len,
2748 			FNV1_32_INIT);
2749 		    onfhp = np->n_fhp;
2750 		    /*
2751 		     * Rehash node for new file handle.
2752 		     */
2753 		    vfs_hash_rehash(vp, hash);
2754 		    np->n_fhp = nfhp;
2755 		    if (onfhp != NULL)
2756 			free(onfhp, M_NFSFH);
2757 		    newvp = NFSTOV(np);
2758 		} else if (NFS_CMPFH(dnp, nfhp->nfh_fh, nfhp->nfh_len)) {
2759 		    free(nfhp, M_NFSFH);
2760 		    VREF(dvp);
2761 		    newvp = dvp;
2762 		} else {
2763 		    cn.cn_nameptr = name;
2764 		    cn.cn_namelen = len;
2765 		    error = nfscl_nget(dvp->v_mount, dvp, nfhp, &cn, td,
2766 			&np, LK_EXCLUSIVE);
2767 		    if (error)
2768 			return (error);
2769 		    newvp = NFSTOV(np);
2770 		    /*
2771 		     * If n_localmodtime >= time before RPC, then
2772 		     * a file modification operation, such as
2773 		     * VOP_SETATTR() of size, has occurred while
2774 		     * the Lookup RPC and acquisition of the vnode
2775 		     * happened.  As such, the attributes might
2776 		     * be stale, with possibly an incorrect size.
2777 		     */
2778 		    NFSLOCKNODE(np);
2779 		    if (timespecisset(&np->n_localmodtime) &&
2780 			timespeccmp(&np->n_localmodtime, &ts, >=)) {
2781 			NFSCL_DEBUG(4, "nfs_lookitup: localmod "
2782 			    "stale attributes\n");
2783 			attrflag = 0;
2784 		    }
2785 		    NFSUNLOCKNODE(np);
2786 		}
2787 		if (!attrflag && *npp == NULL) {
2788 			if (newvp == dvp)
2789 				vrele(newvp);
2790 			else
2791 				vput(newvp);
2792 			return (ENOENT);
2793 		}
2794 		if (attrflag)
2795 			(void) nfscl_loadattrcache(&newvp, &nfsva, NULL, 0, 1);
2796 	}
2797 	if (npp && *npp == NULL) {
2798 		if (error) {
2799 			if (newvp) {
2800 				if (newvp == dvp)
2801 					vrele(newvp);
2802 				else
2803 					vput(newvp);
2804 			}
2805 		} else
2806 			*npp = np;
2807 	}
2808 	if (error && NFS_ISV4(dvp))
2809 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2810 	return (error);
2811 }
2812 
2813 /*
2814  * Nfs Version 3 and 4 commit rpc
2815  */
2816 int
2817 ncl_commit(struct vnode *vp, u_quad_t offset, int cnt, struct ucred *cred,
2818    struct thread *td)
2819 {
2820 	struct nfsvattr nfsva;
2821 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2822 	struct nfsnode *np;
2823 	struct uio uio;
2824 	int error, attrflag;
2825 
2826 	np = VTONFS(vp);
2827 	error = EIO;
2828 	attrflag = 0;
2829 	if (NFSHASPNFS(nmp) && (np->n_flag & NDSCOMMIT) != 0) {
2830 		uio.uio_offset = offset;
2831 		uio.uio_resid = cnt;
2832 		error = nfscl_doiods(vp, &uio, NULL, NULL,
2833 		    NFSV4OPEN_ACCESSWRITE, 1, cred, td);
2834 		if (error != 0) {
2835 			NFSLOCKNODE(np);
2836 			np->n_flag &= ~NDSCOMMIT;
2837 			NFSUNLOCKNODE(np);
2838 		}
2839 	}
2840 	if (error != 0) {
2841 		mtx_lock(&nmp->nm_mtx);
2842 		if ((nmp->nm_state & NFSSTA_HASWRITEVERF) == 0) {
2843 			mtx_unlock(&nmp->nm_mtx);
2844 			return (0);
2845 		}
2846 		mtx_unlock(&nmp->nm_mtx);
2847 		error = nfsrpc_commit(vp, offset, cnt, cred, td, &nfsva,
2848 		    &attrflag);
2849 	}
2850 	if (attrflag != 0)
2851 		(void) nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
2852 	if (error != 0 && NFS_ISV4(vp))
2853 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
2854 	return (error);
2855 }
2856 
2857 /*
2858  * Strategy routine.
2859  * For async requests when nfsiod(s) are running, queue the request by
2860  * calling ncl_asyncio(), otherwise just all ncl_doio() to do the
2861  * request.
2862  */
2863 static int
2864 nfs_strategy(struct vop_strategy_args *ap)
2865 {
2866 	struct buf *bp;
2867 	struct vnode *vp;
2868 	struct ucred *cr;
2869 
2870 	bp = ap->a_bp;
2871 	vp = ap->a_vp;
2872 	KASSERT(bp->b_vp == vp, ("missing b_getvp"));
2873 	KASSERT(!(bp->b_flags & B_DONE),
2874 	    ("nfs_strategy: buffer %p unexpectedly marked B_DONE", bp));
2875 
2876 	if (vp->v_type == VREG && bp->b_blkno == bp->b_lblkno)
2877 		bp->b_blkno = bp->b_lblkno * (vp->v_bufobj.bo_bsize /
2878 		    DEV_BSIZE);
2879 	if (bp->b_iocmd == BIO_READ)
2880 		cr = bp->b_rcred;
2881 	else
2882 		cr = bp->b_wcred;
2883 
2884 	/*
2885 	 * If the op is asynchronous and an i/o daemon is waiting
2886 	 * queue the request, wake it up and wait for completion
2887 	 * otherwise just do it ourselves.
2888 	 */
2889 	if ((bp->b_flags & B_ASYNC) == 0 ||
2890 	    ncl_asyncio(VFSTONFS(vp->v_mount), bp, NOCRED, curthread))
2891 		(void) ncl_doio(vp, bp, cr, curthread, 1);
2892 	return (0);
2893 }
2894 
2895 /*
2896  * fsync vnode op. Just call ncl_flush() with commit == 1.
2897  */
2898 /* ARGSUSED */
2899 static int
2900 nfs_fsync(struct vop_fsync_args *ap)
2901 {
2902 
2903 	if (ap->a_vp->v_type != VREG) {
2904 		/*
2905 		 * For NFS, metadata is changed synchronously on the server,
2906 		 * so there is nothing to flush. Also, ncl_flush() clears
2907 		 * the NMODIFIED flag and that shouldn't be done here for
2908 		 * directories.
2909 		 */
2910 		return (0);
2911 	}
2912 	return (ncl_flush(ap->a_vp, ap->a_waitfor, ap->a_td, 1, 0));
2913 }
2914 
2915 /*
2916  * Flush all the blocks associated with a vnode.
2917  * 	Walk through the buffer pool and push any dirty pages
2918  *	associated with the vnode.
2919  * If the called_from_renewthread argument is TRUE, it has been called
2920  * from the NFSv4 renew thread and, as such, cannot block indefinitely
2921  * waiting for a buffer write to complete.
2922  */
2923 int
2924 ncl_flush(struct vnode *vp, int waitfor, struct thread *td,
2925     int commit, int called_from_renewthread)
2926 {
2927 	struct nfsnode *np = VTONFS(vp);
2928 	struct buf *bp;
2929 	int i;
2930 	struct buf *nbp;
2931 	struct nfsmount *nmp = VFSTONFS(vp->v_mount);
2932 	int error = 0, slptimeo = 0, slpflag = 0, retv, bvecpos;
2933 	int passone = 1, trycnt = 0;
2934 	u_quad_t off, endoff, toff;
2935 	struct ucred* wcred = NULL;
2936 	struct buf **bvec = NULL;
2937 	struct bufobj *bo;
2938 #ifndef NFS_COMMITBVECSIZ
2939 #define	NFS_COMMITBVECSIZ	20
2940 #endif
2941 	struct buf *bvec_on_stack[NFS_COMMITBVECSIZ];
2942 	u_int bvecsize = 0, bveccount;
2943 	struct timespec ts;
2944 
2945 	if (called_from_renewthread != 0)
2946 		slptimeo = hz;
2947 	if (nmp->nm_flag & NFSMNT_INT)
2948 		slpflag = PCATCH;
2949 	if (!commit)
2950 		passone = 0;
2951 	bo = &vp->v_bufobj;
2952 	/*
2953 	 * A b_flags == (B_DELWRI | B_NEEDCOMMIT) block has been written to the
2954 	 * server, but has not been committed to stable storage on the server
2955 	 * yet. On the first pass, the byte range is worked out and the commit
2956 	 * rpc is done. On the second pass, ncl_writebp() is called to do the
2957 	 * job.
2958 	 */
2959 again:
2960 	off = (u_quad_t)-1;
2961 	endoff = 0;
2962 	bvecpos = 0;
2963 	if (NFS_ISV34(vp) && commit) {
2964 		if (bvec != NULL && bvec != bvec_on_stack)
2965 			free(bvec, M_TEMP);
2966 		/*
2967 		 * Count up how many buffers waiting for a commit.
2968 		 */
2969 		bveccount = 0;
2970 		BO_LOCK(bo);
2971 		TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2972 			if (!BUF_ISLOCKED(bp) &&
2973 			    (bp->b_flags & (B_DELWRI | B_NEEDCOMMIT))
2974 				== (B_DELWRI | B_NEEDCOMMIT))
2975 				bveccount++;
2976 		}
2977 		/*
2978 		 * Allocate space to remember the list of bufs to commit.  It is
2979 		 * important to use M_NOWAIT here to avoid a race with nfs_write.
2980 		 * If we can't get memory (for whatever reason), we will end up
2981 		 * committing the buffers one-by-one in the loop below.
2982 		 */
2983 		if (bveccount > NFS_COMMITBVECSIZ) {
2984 			/*
2985 			 * Release the vnode interlock to avoid a lock
2986 			 * order reversal.
2987 			 */
2988 			BO_UNLOCK(bo);
2989 			bvec = (struct buf **)
2990 				malloc(bveccount * sizeof(struct buf *),
2991 				       M_TEMP, M_NOWAIT);
2992 			BO_LOCK(bo);
2993 			if (bvec == NULL) {
2994 				bvec = bvec_on_stack;
2995 				bvecsize = NFS_COMMITBVECSIZ;
2996 			} else
2997 				bvecsize = bveccount;
2998 		} else {
2999 			bvec = bvec_on_stack;
3000 			bvecsize = NFS_COMMITBVECSIZ;
3001 		}
3002 		TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
3003 			if (bvecpos >= bvecsize)
3004 				break;
3005 			if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
3006 				nbp = TAILQ_NEXT(bp, b_bobufs);
3007 				continue;
3008 			}
3009 			if ((bp->b_flags & (B_DELWRI | B_NEEDCOMMIT)) !=
3010 			    (B_DELWRI | B_NEEDCOMMIT)) {
3011 				BUF_UNLOCK(bp);
3012 				nbp = TAILQ_NEXT(bp, b_bobufs);
3013 				continue;
3014 			}
3015 			BO_UNLOCK(bo);
3016 			bremfree(bp);
3017 			/*
3018 			 * Work out if all buffers are using the same cred
3019 			 * so we can deal with them all with one commit.
3020 			 *
3021 			 * NOTE: we are not clearing B_DONE here, so we have
3022 			 * to do it later on in this routine if we intend to
3023 			 * initiate I/O on the bp.
3024 			 *
3025 			 * Note: to avoid loopback deadlocks, we do not
3026 			 * assign b_runningbufspace.
3027 			 */
3028 			if (wcred == NULL)
3029 				wcred = bp->b_wcred;
3030 			else if (wcred != bp->b_wcred)
3031 				wcred = NOCRED;
3032 			vfs_busy_pages(bp, 1);
3033 
3034 			BO_LOCK(bo);
3035 			/*
3036 			 * bp is protected by being locked, but nbp is not
3037 			 * and vfs_busy_pages() may sleep.  We have to
3038 			 * recalculate nbp.
3039 			 */
3040 			nbp = TAILQ_NEXT(bp, b_bobufs);
3041 
3042 			/*
3043 			 * A list of these buffers is kept so that the
3044 			 * second loop knows which buffers have actually
3045 			 * been committed. This is necessary, since there
3046 			 * may be a race between the commit rpc and new
3047 			 * uncommitted writes on the file.
3048 			 */
3049 			bvec[bvecpos++] = bp;
3050 			toff = ((u_quad_t)bp->b_blkno) * DEV_BSIZE +
3051 				bp->b_dirtyoff;
3052 			if (toff < off)
3053 				off = toff;
3054 			toff += (u_quad_t)(bp->b_dirtyend - bp->b_dirtyoff);
3055 			if (toff > endoff)
3056 				endoff = toff;
3057 		}
3058 		BO_UNLOCK(bo);
3059 	}
3060 	if (bvecpos > 0) {
3061 		/*
3062 		 * Commit data on the server, as required.
3063 		 * If all bufs are using the same wcred, then use that with
3064 		 * one call for all of them, otherwise commit each one
3065 		 * separately.
3066 		 */
3067 		if (wcred != NOCRED)
3068 			retv = ncl_commit(vp, off, (int)(endoff - off),
3069 					  wcred, td);
3070 		else {
3071 			retv = 0;
3072 			for (i = 0; i < bvecpos; i++) {
3073 				off_t off, size;
3074 				bp = bvec[i];
3075 				off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE +
3076 					bp->b_dirtyoff;
3077 				size = (u_quad_t)(bp->b_dirtyend
3078 						  - bp->b_dirtyoff);
3079 				retv = ncl_commit(vp, off, (int)size,
3080 						  bp->b_wcred, td);
3081 				if (retv) break;
3082 			}
3083 		}
3084 
3085 		if (retv == NFSERR_STALEWRITEVERF)
3086 			ncl_clearcommit(vp->v_mount);
3087 
3088 		/*
3089 		 * Now, either mark the blocks I/O done or mark the
3090 		 * blocks dirty, depending on whether the commit
3091 		 * succeeded.
3092 		 */
3093 		for (i = 0; i < bvecpos; i++) {
3094 			bp = bvec[i];
3095 			bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
3096 			if (!NFSCL_FORCEDISM(vp->v_mount) && retv) {
3097 				/*
3098 				 * Error, leave B_DELWRI intact
3099 				 */
3100 				vfs_unbusy_pages(bp);
3101 				brelse(bp);
3102 			} else {
3103 				/*
3104 				 * Success, remove B_DELWRI ( bundirty() ).
3105 				 *
3106 				 * b_dirtyoff/b_dirtyend seem to be NFS
3107 				 * specific.  We should probably move that
3108 				 * into bundirty(). XXX
3109 				 */
3110 				bufobj_wref(bo);
3111 				bp->b_flags |= B_ASYNC;
3112 				bundirty(bp);
3113 				bp->b_flags &= ~B_DONE;
3114 				bp->b_ioflags &= ~BIO_ERROR;
3115 				bp->b_dirtyoff = bp->b_dirtyend = 0;
3116 				bufdone(bp);
3117 			}
3118 		}
3119 	}
3120 
3121 	/*
3122 	 * Start/do any write(s) that are required.
3123 	 */
3124 loop:
3125 	BO_LOCK(bo);
3126 	TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
3127 		if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
3128 			if (waitfor != MNT_WAIT || passone)
3129 				continue;
3130 
3131 			error = BUF_TIMELOCK(bp,
3132 			    LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
3133 			    BO_LOCKPTR(bo), "nfsfsync", slpflag, slptimeo);
3134 			if (error == 0) {
3135 				BUF_UNLOCK(bp);
3136 				goto loop;
3137 			}
3138 			if (error == ENOLCK) {
3139 				error = 0;
3140 				goto loop;
3141 			}
3142 			if (called_from_renewthread != 0) {
3143 				/*
3144 				 * Return EIO so the flush will be retried
3145 				 * later.
3146 				 */
3147 				error = EIO;
3148 				goto done;
3149 			}
3150 			if (newnfs_sigintr(nmp, td)) {
3151 				error = EINTR;
3152 				goto done;
3153 			}
3154 			if (slpflag == PCATCH) {
3155 				slpflag = 0;
3156 				slptimeo = 2 * hz;
3157 			}
3158 			goto loop;
3159 		}
3160 		if ((bp->b_flags & B_DELWRI) == 0)
3161 			panic("nfs_fsync: not dirty");
3162 		if ((passone || !commit) && (bp->b_flags & B_NEEDCOMMIT)) {
3163 			BUF_UNLOCK(bp);
3164 			continue;
3165 		}
3166 		BO_UNLOCK(bo);
3167 		bremfree(bp);
3168 		bp->b_flags |= B_ASYNC;
3169 		bwrite(bp);
3170 		if (newnfs_sigintr(nmp, td)) {
3171 			error = EINTR;
3172 			goto done;
3173 		}
3174 		goto loop;
3175 	}
3176 	if (passone) {
3177 		passone = 0;
3178 		BO_UNLOCK(bo);
3179 		goto again;
3180 	}
3181 	if (waitfor == MNT_WAIT) {
3182 		while (bo->bo_numoutput) {
3183 			error = bufobj_wwait(bo, slpflag, slptimeo);
3184 			if (error) {
3185 			    BO_UNLOCK(bo);
3186 			    if (called_from_renewthread != 0) {
3187 				/*
3188 				 * Return EIO so that the flush will be
3189 				 * retried later.
3190 				 */
3191 				error = EIO;
3192 				goto done;
3193 			    }
3194 			    error = newnfs_sigintr(nmp, td);
3195 			    if (error)
3196 				goto done;
3197 			    if (slpflag == PCATCH) {
3198 				slpflag = 0;
3199 				slptimeo = 2 * hz;
3200 			    }
3201 			    BO_LOCK(bo);
3202 			}
3203 		}
3204 		if (bo->bo_dirty.bv_cnt != 0 && commit) {
3205 			BO_UNLOCK(bo);
3206 			goto loop;
3207 		}
3208 		/*
3209 		 * Wait for all the async IO requests to drain
3210 		 */
3211 		BO_UNLOCK(bo);
3212 		NFSLOCKNODE(np);
3213 		while (np->n_directio_asyncwr > 0) {
3214 			np->n_flag |= NFSYNCWAIT;
3215 			error = newnfs_msleep(td, &np->n_directio_asyncwr,
3216 			    &np->n_mtx, slpflag | (PRIBIO + 1),
3217 			    "nfsfsync", 0);
3218 			if (error) {
3219 				if (newnfs_sigintr(nmp, td)) {
3220 					NFSUNLOCKNODE(np);
3221 					error = EINTR;
3222 					goto done;
3223 				}
3224 			}
3225 		}
3226 		NFSUNLOCKNODE(np);
3227 	} else
3228 		BO_UNLOCK(bo);
3229 	if (NFSHASPNFS(nmp)) {
3230 		nfscl_layoutcommit(vp, td);
3231 		/*
3232 		 * Invalidate the attribute cache, since writes to a DS
3233 		 * won't update the size attribute.
3234 		 */
3235 		NFSLOCKNODE(np);
3236 		np->n_attrstamp = 0;
3237 	} else
3238 		NFSLOCKNODE(np);
3239 	if (np->n_flag & NWRITEERR) {
3240 		error = np->n_error;
3241 		np->n_flag &= ~NWRITEERR;
3242 	}
3243   	if (commit && bo->bo_dirty.bv_cnt == 0 &&
3244 	    bo->bo_numoutput == 0 && np->n_directio_asyncwr == 0)
3245   		np->n_flag &= ~NMODIFIED;
3246 	NFSUNLOCKNODE(np);
3247 done:
3248 	if (bvec != NULL && bvec != bvec_on_stack)
3249 		free(bvec, M_TEMP);
3250 	if (error == 0 && commit != 0 && waitfor == MNT_WAIT &&
3251 	    (bo->bo_dirty.bv_cnt != 0 || bo->bo_numoutput != 0 ||
3252 	    np->n_directio_asyncwr != 0)) {
3253 		if (trycnt++ < 5) {
3254 			/* try, try again... */
3255 			passone = 1;
3256 			wcred = NULL;
3257 			bvec = NULL;
3258 			bvecsize = 0;
3259 			goto again;
3260 		}
3261 		vn_printf(vp, "ncl_flush failed");
3262 		error = called_from_renewthread != 0 ? EIO : EBUSY;
3263 	}
3264 	if (error == 0) {
3265 		nanouptime(&ts);
3266 		NFSLOCKNODE(np);
3267 		np->n_localmodtime = ts;
3268 		NFSUNLOCKNODE(np);
3269 	}
3270 	return (error);
3271 }
3272 
3273 /*
3274  * NFS advisory byte-level locks.
3275  */
3276 static int
3277 nfs_advlock(struct vop_advlock_args *ap)
3278 {
3279 	struct vnode *vp = ap->a_vp;
3280 	struct ucred *cred;
3281 	struct nfsnode *np = VTONFS(ap->a_vp);
3282 	struct proc *p = (struct proc *)ap->a_id;
3283 	struct thread *td = curthread;	/* XXX */
3284 	struct vattr va;
3285 	int ret, error;
3286 	u_quad_t size;
3287 	struct nfsmount *nmp;
3288 
3289 	error = NFSVOPLOCK(vp, LK_SHARED);
3290 	if (error != 0)
3291 		return (EBADF);
3292 	if (NFS_ISV4(vp) && (ap->a_flags & (F_POSIX | F_FLOCK)) != 0) {
3293 		if (vp->v_type != VREG) {
3294 			error = EINVAL;
3295 			goto out;
3296 		}
3297 		if ((ap->a_flags & F_POSIX) != 0)
3298 			cred = p->p_ucred;
3299 		else
3300 			cred = td->td_ucred;
3301 		NFSVOPLOCK(vp, LK_UPGRADE | LK_RETRY);
3302 		if (VN_IS_DOOMED(vp)) {
3303 			error = EBADF;
3304 			goto out;
3305 		}
3306 
3307 		/*
3308 		 * If this is unlocking a write locked region, flush and
3309 		 * commit them before unlocking. This is required by
3310 		 * RFC3530 Sec. 9.3.2.
3311 		 */
3312 		if (ap->a_op == F_UNLCK &&
3313 		    nfscl_checkwritelocked(vp, ap->a_fl, cred, td, ap->a_id,
3314 		    ap->a_flags))
3315 			(void) ncl_flush(vp, MNT_WAIT, td, 1, 0);
3316 
3317 		/*
3318 		 * Mark NFS node as might have acquired a lock.
3319 		 * This is separate from NHASBEENLOCKED, because it must
3320 		 * be done before the nfsrpc_advlock() call, which might
3321 		 * add a nfscllock structure to the client state.
3322 		 * It is used to check for the case where a nfscllock
3323 		 * state structure cannot exist for the file.
3324 		 * Only done for "oneopenown" NFSv4.1/4.2 mounts.
3325 		 */
3326 		nmp = VFSTONFS(vp->v_mount);
3327 		if (NFSHASNFSV4N(nmp) && NFSHASONEOPENOWN(nmp)) {
3328 			NFSLOCKNODE(np);
3329 			np->n_flag |= NMIGHTBELOCKED;
3330 			NFSUNLOCKNODE(np);
3331 		}
3332 
3333 		/*
3334 		 * Loop around doing the lock op, while a blocking lock
3335 		 * must wait for the lock op to succeed.
3336 		 */
3337 		do {
3338 			ret = nfsrpc_advlock(vp, np->n_size, ap->a_op,
3339 			    ap->a_fl, 0, cred, td, ap->a_id, ap->a_flags);
3340 			if (ret == NFSERR_DENIED && (ap->a_flags & F_WAIT) &&
3341 			    ap->a_op == F_SETLK) {
3342 				NFSVOPUNLOCK(vp);
3343 				error = nfs_catnap(PZERO | PCATCH, ret,
3344 				    "ncladvl");
3345 				if (error)
3346 					return (EINTR);
3347 				NFSVOPLOCK(vp, LK_EXCLUSIVE | LK_RETRY);
3348 				if (VN_IS_DOOMED(vp)) {
3349 					error = EBADF;
3350 					goto out;
3351 				}
3352 			}
3353 		} while (ret == NFSERR_DENIED && (ap->a_flags & F_WAIT) &&
3354 		     ap->a_op == F_SETLK);
3355 		if (ret == NFSERR_DENIED) {
3356 			error = EAGAIN;
3357 			goto out;
3358 		} else if (ret == EINVAL || ret == EBADF || ret == EINTR) {
3359 			error = ret;
3360 			goto out;
3361 		} else if (ret != 0) {
3362 			error = EACCES;
3363 			goto out;
3364 		}
3365 
3366 		/*
3367 		 * Now, if we just got a lock, invalidate data in the buffer
3368 		 * cache, as required, so that the coherency conforms with
3369 		 * RFC3530 Sec. 9.3.2.
3370 		 */
3371 		if (ap->a_op == F_SETLK) {
3372 			if ((np->n_flag & NMODIFIED) == 0) {
3373 				np->n_attrstamp = 0;
3374 				KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
3375 				ret = VOP_GETATTR(vp, &va, cred);
3376 			}
3377 			if ((np->n_flag & NMODIFIED) || ret ||
3378 			    np->n_change != va.va_filerev) {
3379 				(void) ncl_vinvalbuf(vp, V_SAVE, td, 1);
3380 				np->n_attrstamp = 0;
3381 				KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
3382 				ret = VOP_GETATTR(vp, &va, cred);
3383 				if (!ret) {
3384 					np->n_mtime = va.va_mtime;
3385 					np->n_change = va.va_filerev;
3386 				}
3387 			}
3388 			/* Mark that a file lock has been acquired. */
3389 			NFSLOCKNODE(np);
3390 			np->n_flag |= NHASBEENLOCKED;
3391 			NFSUNLOCKNODE(np);
3392 		}
3393 	} else if (!NFS_ISV4(vp)) {
3394 		if ((VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NOLOCKD) != 0) {
3395 			size = VTONFS(vp)->n_size;
3396 			NFSVOPUNLOCK(vp);
3397 			error = lf_advlock(ap, &(vp->v_lockf), size);
3398 		} else {
3399 			if (nfs_advlock_p != NULL)
3400 				error = nfs_advlock_p(ap);
3401 			else {
3402 				NFSVOPUNLOCK(vp);
3403 				error = ENOLCK;
3404 			}
3405 		}
3406 		if (error == 0 && ap->a_op == F_SETLK) {
3407 			error = NFSVOPLOCK(vp, LK_SHARED);
3408 			if (error == 0) {
3409 				/* Mark that a file lock has been acquired. */
3410 				NFSLOCKNODE(np);
3411 				np->n_flag |= NHASBEENLOCKED;
3412 				NFSUNLOCKNODE(np);
3413 				NFSVOPUNLOCK(vp);
3414 			}
3415 		}
3416 		return (error);
3417 	} else
3418 		error = EOPNOTSUPP;
3419 out:
3420 	NFSVOPUNLOCK(vp);
3421 	return (error);
3422 }
3423 
3424 /*
3425  * NFS advisory byte-level locks.
3426  */
3427 static int
3428 nfs_advlockasync(struct vop_advlockasync_args *ap)
3429 {
3430 	struct vnode *vp = ap->a_vp;
3431 	u_quad_t size;
3432 	int error;
3433 
3434 	if (NFS_ISV4(vp))
3435 		return (EOPNOTSUPP);
3436 	error = NFSVOPLOCK(vp, LK_SHARED);
3437 	if (error)
3438 		return (error);
3439 	if ((VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NOLOCKD) != 0) {
3440 		size = VTONFS(vp)->n_size;
3441 		NFSVOPUNLOCK(vp);
3442 		error = lf_advlockasync(ap, &(vp->v_lockf), size);
3443 	} else {
3444 		NFSVOPUNLOCK(vp);
3445 		error = EOPNOTSUPP;
3446 	}
3447 	return (error);
3448 }
3449 
3450 /*
3451  * Print out the contents of an nfsnode.
3452  */
3453 static int
3454 nfs_print(struct vop_print_args *ap)
3455 {
3456 	struct vnode *vp = ap->a_vp;
3457 	struct nfsnode *np = VTONFS(vp);
3458 
3459 	printf("\tfileid %jd fsid 0x%jx", (uintmax_t)np->n_vattr.na_fileid,
3460 	    (uintmax_t)np->n_vattr.na_fsid);
3461 	if (vp->v_type == VFIFO)
3462 		fifo_printinfo(vp);
3463 	printf("\n");
3464 	return (0);
3465 }
3466 
3467 /*
3468  * This is the "real" nfs::bwrite(struct buf*).
3469  * We set B_CACHE if this is a VMIO buffer.
3470  */
3471 int
3472 ncl_writebp(struct buf *bp, int force __unused, struct thread *td)
3473 {
3474 	int oldflags, rtval;
3475 
3476 	if (bp->b_flags & B_INVAL) {
3477 		brelse(bp);
3478 		return (0);
3479 	}
3480 
3481 	oldflags = bp->b_flags;
3482 	bp->b_flags |= B_CACHE;
3483 
3484 	/*
3485 	 * Undirty the bp.  We will redirty it later if the I/O fails.
3486 	 */
3487 	bundirty(bp);
3488 	bp->b_flags &= ~B_DONE;
3489 	bp->b_ioflags &= ~BIO_ERROR;
3490 	bp->b_iocmd = BIO_WRITE;
3491 
3492 	bufobj_wref(bp->b_bufobj);
3493 	curthread->td_ru.ru_oublock++;
3494 
3495 	/*
3496 	 * Note: to avoid loopback deadlocks, we do not
3497 	 * assign b_runningbufspace.
3498 	 */
3499 	vfs_busy_pages(bp, 1);
3500 
3501 	BUF_KERNPROC(bp);
3502 	bp->b_iooffset = dbtob(bp->b_blkno);
3503 	bstrategy(bp);
3504 
3505 	if ((oldflags & B_ASYNC) != 0)
3506 		return (0);
3507 
3508 	rtval = bufwait(bp);
3509 	if (oldflags & B_DELWRI)
3510 		reassignbuf(bp);
3511 	brelse(bp);
3512 	return (rtval);
3513 }
3514 
3515 /*
3516  * nfs special file access vnode op.
3517  * Essentially just get vattr and then imitate iaccess() since the device is
3518  * local to the client.
3519  */
3520 static int
3521 nfsspec_access(struct vop_access_args *ap)
3522 {
3523 	struct vattr *vap;
3524 	struct ucred *cred = ap->a_cred;
3525 	struct vnode *vp = ap->a_vp;
3526 	accmode_t accmode = ap->a_accmode;
3527 	struct vattr vattr;
3528 	int error;
3529 
3530 	/*
3531 	 * Disallow write attempts on filesystems mounted read-only;
3532 	 * unless the file is a socket, fifo, or a block or character
3533 	 * device resident on the filesystem.
3534 	 */
3535 	if ((accmode & VWRITE) && (vp->v_mount->mnt_flag & MNT_RDONLY)) {
3536 		switch (vp->v_type) {
3537 		case VREG:
3538 		case VDIR:
3539 		case VLNK:
3540 			return (EROFS);
3541 		default:
3542 			break;
3543 		}
3544 	}
3545 	vap = &vattr;
3546 	error = VOP_GETATTR(vp, vap, cred);
3547 	if (error)
3548 		goto out;
3549 	error = vaccess(vp->v_type, vap->va_mode, vap->va_uid, vap->va_gid,
3550 	    accmode, cred);
3551 out:
3552 	return error;
3553 }
3554 
3555 /*
3556  * Read wrapper for fifos.
3557  */
3558 static int
3559 nfsfifo_read(struct vop_read_args *ap)
3560 {
3561 	struct nfsnode *np = VTONFS(ap->a_vp);
3562 	int error;
3563 
3564 	/*
3565 	 * Set access flag.
3566 	 */
3567 	NFSLOCKNODE(np);
3568 	np->n_flag |= NACC;
3569 	vfs_timestamp(&np->n_atim);
3570 	NFSUNLOCKNODE(np);
3571 	error = fifo_specops.vop_read(ap);
3572 	return error;
3573 }
3574 
3575 /*
3576  * Write wrapper for fifos.
3577  */
3578 static int
3579 nfsfifo_write(struct vop_write_args *ap)
3580 {
3581 	struct nfsnode *np = VTONFS(ap->a_vp);
3582 
3583 	/*
3584 	 * Set update flag.
3585 	 */
3586 	NFSLOCKNODE(np);
3587 	np->n_flag |= NUPD;
3588 	vfs_timestamp(&np->n_mtim);
3589 	NFSUNLOCKNODE(np);
3590 	return(fifo_specops.vop_write(ap));
3591 }
3592 
3593 /*
3594  * Close wrapper for fifos.
3595  *
3596  * Update the times on the nfsnode then do fifo close.
3597  */
3598 static int
3599 nfsfifo_close(struct vop_close_args *ap)
3600 {
3601 	struct vnode *vp = ap->a_vp;
3602 	struct nfsnode *np = VTONFS(vp);
3603 	struct vattr vattr;
3604 	struct timespec ts;
3605 
3606 	NFSLOCKNODE(np);
3607 	if (np->n_flag & (NACC | NUPD)) {
3608 		vfs_timestamp(&ts);
3609 		if (np->n_flag & NACC)
3610 			np->n_atim = ts;
3611 		if (np->n_flag & NUPD)
3612 			np->n_mtim = ts;
3613 		np->n_flag |= NCHG;
3614 		if (vrefcnt(vp) == 1 &&
3615 		    (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
3616 			VATTR_NULL(&vattr);
3617 			if (np->n_flag & NACC)
3618 				vattr.va_atime = np->n_atim;
3619 			if (np->n_flag & NUPD)
3620 				vattr.va_mtime = np->n_mtim;
3621 			NFSUNLOCKNODE(np);
3622 			(void)VOP_SETATTR(vp, &vattr, ap->a_cred);
3623 			goto out;
3624 		}
3625 	}
3626 	NFSUNLOCKNODE(np);
3627 out:
3628 	return (fifo_specops.vop_close(ap));
3629 }
3630 
3631 /*
3632  * Just call ncl_writebp() with the force argument set to 1.
3633  *
3634  * NOTE: B_DONE may or may not be set in a_bp on call.
3635  */
3636 static int
3637 nfs_bwrite(struct buf *bp)
3638 {
3639 
3640 	return (ncl_writebp(bp, 1, curthread));
3641 }
3642 
3643 struct buf_ops buf_ops_newnfs = {
3644 	.bop_name	=	"buf_ops_nfs",
3645 	.bop_write	=	nfs_bwrite,
3646 	.bop_strategy	=	bufstrategy,
3647 	.bop_sync	=	bufsync,
3648 	.bop_bdflush	=	bufbdflush,
3649 };
3650 
3651 static int
3652 nfs_getacl(struct vop_getacl_args *ap)
3653 {
3654 	int error;
3655 
3656 	if (ap->a_type != ACL_TYPE_NFS4)
3657 		return (EOPNOTSUPP);
3658 	error = nfsrpc_getacl(ap->a_vp, ap->a_cred, ap->a_td, ap->a_aclp);
3659 	if (error > NFSERR_STALE) {
3660 		(void) nfscl_maperr(ap->a_td, error, (uid_t)0, (gid_t)0);
3661 		error = EPERM;
3662 	}
3663 	return (error);
3664 }
3665 
3666 static int
3667 nfs_setacl(struct vop_setacl_args *ap)
3668 {
3669 	int error;
3670 
3671 	if (ap->a_type != ACL_TYPE_NFS4)
3672 		return (EOPNOTSUPP);
3673 	error = nfsrpc_setacl(ap->a_vp, ap->a_cred, ap->a_td, ap->a_aclp);
3674 	if (error > NFSERR_STALE) {
3675 		(void) nfscl_maperr(ap->a_td, error, (uid_t)0, (gid_t)0);
3676 		error = EPERM;
3677 	}
3678 	return (error);
3679 }
3680 
3681 /*
3682  * VOP_ADVISE for NFS.
3683  * Just return 0 for any errors, since it is just a hint.
3684  */
3685 static int
3686 nfs_advise(struct vop_advise_args *ap)
3687 {
3688 	struct thread *td = curthread;
3689 	struct nfsmount *nmp;
3690 	uint64_t len;
3691 	int error;
3692 
3693 	/*
3694 	 * First do vop_stdadvise() to handle the buffer cache.
3695 	 */
3696 	error = vop_stdadvise(ap);
3697 	if (error != 0)
3698 		return (error);
3699 	if (ap->a_start < 0 || ap->a_end < 0)
3700 		return (0);
3701 	if (ap->a_end == OFF_MAX)
3702 		len = 0;
3703 	else if (ap->a_end < ap->a_start)
3704 		return (0);
3705 	else
3706 		len = ap->a_end - ap->a_start + 1;
3707 	nmp = VFSTONFS(ap->a_vp->v_mount);
3708 	mtx_lock(&nmp->nm_mtx);
3709 	if (!NFSHASNFSV4(nmp) || nmp->nm_minorvers < NFSV42_MINORVERSION ||
3710 	    (NFSHASPNFS(nmp) && (nmp->nm_privflag & NFSMNTP_IOADVISETHRUMDS) ==
3711 	    0) || (nmp->nm_privflag & NFSMNTP_NOADVISE) != 0) {
3712 		mtx_unlock(&nmp->nm_mtx);
3713 		return (0);
3714 	}
3715 	mtx_unlock(&nmp->nm_mtx);
3716 	error = nfsrpc_advise(ap->a_vp, ap->a_start, len, ap->a_advice,
3717 	    td->td_ucred, td);
3718 	if (error == NFSERR_NOTSUPP) {
3719 		mtx_lock(&nmp->nm_mtx);
3720 		nmp->nm_privflag |= NFSMNTP_NOADVISE;
3721 		mtx_unlock(&nmp->nm_mtx);
3722 	}
3723 	return (0);
3724 }
3725 
3726 /*
3727  * nfs allocate call
3728  */
3729 static int
3730 nfs_allocate(struct vop_allocate_args *ap)
3731 {
3732 	struct vnode *vp = ap->a_vp;
3733 	struct thread *td = curthread;
3734 	struct nfsvattr nfsva;
3735 	struct nfsmount *nmp;
3736 	struct nfsnode *np;
3737 	off_t alen;
3738 	int attrflag, error, ret;
3739 	struct timespec ts;
3740 	struct uio io;
3741 
3742 	attrflag = 0;
3743 	nmp = VFSTONFS(vp->v_mount);
3744 	np = VTONFS(vp);
3745 	mtx_lock(&nmp->nm_mtx);
3746 	if (NFSHASNFSV4(nmp) && nmp->nm_minorvers >= NFSV42_MINORVERSION &&
3747 	    (nmp->nm_privflag & NFSMNTP_NOALLOCATE) == 0) {
3748 		mtx_unlock(&nmp->nm_mtx);
3749 		alen = *ap->a_len;
3750 		if ((uint64_t)alen > nfs_maxalloclen)
3751 			alen = nfs_maxalloclen;
3752 
3753 		/* Check the file size limit. */
3754 		io.uio_offset = *ap->a_offset;
3755 		io.uio_resid = alen;
3756 		error = vn_rlimit_fsize(vp, &io, td);
3757 
3758 		/*
3759 		 * Flush first to ensure that the allocate adds to the
3760 		 * file's allocation on the server.
3761 		 */
3762 		if (error == 0)
3763 			error = ncl_flush(vp, MNT_WAIT, td, 1, 0);
3764 		if (error == 0)
3765 			error = nfsrpc_allocate(vp, *ap->a_offset, alen,
3766 			    &nfsva, &attrflag, ap->a_cred, td);
3767 		if (error == 0) {
3768 			*ap->a_offset += alen;
3769 			*ap->a_len -= alen;
3770 			nanouptime(&ts);
3771 			NFSLOCKNODE(np);
3772 			np->n_localmodtime = ts;
3773 			NFSUNLOCKNODE(np);
3774 		} else if (error == NFSERR_NOTSUPP) {
3775 			mtx_lock(&nmp->nm_mtx);
3776 			nmp->nm_privflag |= NFSMNTP_NOALLOCATE;
3777 			mtx_unlock(&nmp->nm_mtx);
3778 			error = EINVAL;
3779 		}
3780 	} else {
3781 		mtx_unlock(&nmp->nm_mtx);
3782 		error = EINVAL;
3783 	}
3784 	if (attrflag != 0) {
3785 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
3786 		if (error == 0 && ret != 0)
3787 			error = ret;
3788 	}
3789 	if (error != 0)
3790 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
3791 	return (error);
3792 }
3793 
3794 /*
3795  * nfs deallocate call
3796  */
3797 static int
3798 nfs_deallocate(struct vop_deallocate_args *ap)
3799 {
3800 	struct vnode *vp = ap->a_vp;
3801 	struct thread *td = curthread;
3802 	struct nfsvattr nfsva;
3803 	struct nfsmount *nmp;
3804 	struct nfsnode *np;
3805 	off_t tlen, mlen;
3806 	int attrflag, error, ret;
3807 	bool clipped;
3808 	struct timespec ts;
3809 
3810 	error = 0;
3811 	attrflag = 0;
3812 	nmp = VFSTONFS(vp->v_mount);
3813 	np = VTONFS(vp);
3814 	mtx_lock(&nmp->nm_mtx);
3815 	if (NFSHASNFSV4(nmp) && nmp->nm_minorvers >= NFSV42_MINORVERSION &&
3816 	    (nmp->nm_privflag & NFSMNTP_NODEALLOCATE) == 0) {
3817 		mtx_unlock(&nmp->nm_mtx);
3818 		tlen = omin(OFF_MAX - *ap->a_offset, *ap->a_len);
3819 		NFSCL_DEBUG(4, "dealloc: off=%jd len=%jd maxfilesize=%ju\n",
3820 		    (intmax_t)*ap->a_offset, (intmax_t)tlen,
3821 		    (uintmax_t)nmp->nm_maxfilesize);
3822 		if ((uint64_t)*ap->a_offset >= nmp->nm_maxfilesize) {
3823 			/* Avoid EFBIG error return from the NFSv4.2 server. */
3824 			*ap->a_len = 0;
3825 			return (0);
3826 		}
3827 		clipped = false;
3828 		if ((uint64_t)*ap->a_offset + tlen > nmp->nm_maxfilesize)
3829 			tlen = nmp->nm_maxfilesize - *ap->a_offset;
3830 		if ((uint64_t)*ap->a_offset < np->n_size) {
3831 			/* Limit the len to nfs_maxalloclen before EOF. */
3832 			mlen = omin((off_t)np->n_size - *ap->a_offset, tlen);
3833 			if ((uint64_t)mlen > nfs_maxalloclen) {
3834 				NFSCL_DEBUG(4, "dealloc: tlen maxalloclen\n");
3835 				tlen = nfs_maxalloclen;
3836 				clipped = true;
3837 			}
3838 		}
3839 		if (error == 0)
3840 			error = ncl_vinvalbuf(vp, V_SAVE, td, 1);
3841 		if (error == 0) {
3842 			vnode_pager_purge_range(vp, *ap->a_offset,
3843 			    *ap->a_offset + tlen);
3844 			error = nfsrpc_deallocate(vp, *ap->a_offset, tlen,
3845 			    &nfsva, &attrflag, ap->a_cred, td);
3846 			NFSCL_DEBUG(4, "dealloc: rpc=%d\n", error);
3847 		}
3848 		if (error == 0) {
3849 			NFSCL_DEBUG(4, "dealloc: attrflag=%d na_size=%ju\n",
3850 			    attrflag, (uintmax_t)nfsva.na_size);
3851 			nanouptime(&ts);
3852 			NFSLOCKNODE(np);
3853 			np->n_localmodtime = ts;
3854 			NFSUNLOCKNODE(np);
3855 			if (attrflag != 0) {
3856 				if ((uint64_t)*ap->a_offset < nfsva.na_size)
3857 					*ap->a_offset += omin((off_t)
3858 					    nfsva.na_size - *ap->a_offset,
3859 					    tlen);
3860 			}
3861 			if (clipped && tlen < *ap->a_len)
3862 				*ap->a_len -= tlen;
3863 			else
3864 				*ap->a_len = 0;
3865 		} else if (error == NFSERR_NOTSUPP) {
3866 			mtx_lock(&nmp->nm_mtx);
3867 			nmp->nm_privflag |= NFSMNTP_NODEALLOCATE;
3868 			mtx_unlock(&nmp->nm_mtx);
3869 		}
3870 	} else {
3871 		mtx_unlock(&nmp->nm_mtx);
3872 		error = EIO;
3873 	}
3874 	/*
3875 	 * If the NFS server cannot perform the Deallocate operation, just call
3876 	 * vop_stddeallocate() to perform it.
3877 	 */
3878 	if (error != 0 && error != NFSERR_FBIG && error != NFSERR_INVAL) {
3879 		error = vop_stddeallocate(ap);
3880 		NFSCL_DEBUG(4, "dealloc: stddeallocate=%d\n", error);
3881 	}
3882 	if (attrflag != 0) {
3883 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
3884 		if (error == 0 && ret != 0)
3885 			error = ret;
3886 	}
3887 	if (error != 0)
3888 		error = nfscl_maperr(td, error, (uid_t)0, (gid_t)0);
3889 	return (error);
3890 }
3891 
3892 /*
3893  * nfs copy_file_range call
3894  */
3895 static int
3896 nfs_copy_file_range(struct vop_copy_file_range_args *ap)
3897 {
3898 	struct vnode *invp = ap->a_invp;
3899 	struct vnode *outvp = ap->a_outvp;
3900 	struct mount *mp;
3901 	struct nfsvattr innfsva, outnfsva;
3902 	struct vattr *vap;
3903 	struct uio io;
3904 	struct nfsmount *nmp;
3905 	size_t len, len2;
3906 	int error, inattrflag, outattrflag, ret, ret2;
3907 	off_t inoff, outoff;
3908 	bool consecutive, must_commit, tryoutcred;
3909 
3910 	ret = ret2 = 0;
3911 	nmp = VFSTONFS(invp->v_mount);
3912 	mtx_lock(&nmp->nm_mtx);
3913 	/* NFSv4.2 Copy is not permitted for infile == outfile. */
3914 	if (!NFSHASNFSV4(nmp) || nmp->nm_minorvers < NFSV42_MINORVERSION ||
3915 	    (nmp->nm_privflag & NFSMNTP_NOCOPY) != 0 || invp == outvp) {
3916 		mtx_unlock(&nmp->nm_mtx);
3917 		error = vn_generic_copy_file_range(ap->a_invp, ap->a_inoffp,
3918 		    ap->a_outvp, ap->a_outoffp, ap->a_lenp, ap->a_flags,
3919 		    ap->a_incred, ap->a_outcred, ap->a_fsizetd);
3920 		return (error);
3921 	}
3922 	mtx_unlock(&nmp->nm_mtx);
3923 
3924 	/* Lock both vnodes, avoiding risk of deadlock. */
3925 	do {
3926 		mp = NULL;
3927 		error = vn_start_write(outvp, &mp, V_WAIT);
3928 		if (error == 0) {
3929 			error = vn_lock(outvp, LK_EXCLUSIVE);
3930 			if (error == 0) {
3931 				error = vn_lock(invp, LK_SHARED | LK_NOWAIT);
3932 				if (error == 0)
3933 					break;
3934 				VOP_UNLOCK(outvp);
3935 				if (mp != NULL)
3936 					vn_finished_write(mp);
3937 				mp = NULL;
3938 				error = vn_lock(invp, LK_SHARED);
3939 				if (error == 0)
3940 					VOP_UNLOCK(invp);
3941 			}
3942 		}
3943 		if (mp != NULL)
3944 			vn_finished_write(mp);
3945 	} while (error == 0);
3946 	if (error != 0)
3947 		return (error);
3948 
3949 	/*
3950 	 * Do the vn_rlimit_fsize() check.  Should this be above the VOP layer?
3951 	 */
3952 	io.uio_offset = *ap->a_outoffp;
3953 	io.uio_resid = *ap->a_lenp;
3954 	error = vn_rlimit_fsize(outvp, &io, ap->a_fsizetd);
3955 
3956 	/*
3957 	 * Flush the input file so that the data is up to date before
3958 	 * the copy.  Flush writes for the output file so that they
3959 	 * do not overwrite the data copied to the output file by the Copy.
3960 	 * Set the commit argument for both flushes so that the data is on
3961 	 * stable storage before the Copy RPC.  This is done in case the
3962 	 * server reboots during the Copy and needs to be redone.
3963 	 */
3964 	if (error == 0)
3965 		error = ncl_flush(invp, MNT_WAIT, curthread, 1, 0);
3966 	if (error == 0)
3967 		error = ncl_flush(outvp, MNT_WAIT, curthread, 1, 0);
3968 
3969 	/* Do the actual NFSv4.2 RPC. */
3970 	len = *ap->a_lenp;
3971 	mtx_lock(&nmp->nm_mtx);
3972 	if ((nmp->nm_privflag & NFSMNTP_NOCONSECUTIVE) == 0)
3973 		consecutive = true;
3974 	else
3975 		consecutive = false;
3976 	mtx_unlock(&nmp->nm_mtx);
3977 	inoff = *ap->a_inoffp;
3978 	outoff = *ap->a_outoffp;
3979 	tryoutcred = true;
3980 	must_commit = false;
3981 	if (error == 0) {
3982 		vap = &VTONFS(invp)->n_vattr.na_vattr;
3983 		error = VOP_GETATTR(invp, vap, ap->a_incred);
3984 		if (error == 0) {
3985 			/*
3986 			 * Clip "len" at va_size so that RFC compliant servers
3987 			 * will not reply NFSERR_INVAL.
3988 			 * Setting "len == 0" for the RPC would be preferred,
3989 			 * but some Linux servers do not support that.
3990 			 */
3991 			if (inoff >= vap->va_size)
3992 				*ap->a_lenp = len = 0;
3993 			else if (inoff + len > vap->va_size)
3994 				*ap->a_lenp = len = vap->va_size - inoff;
3995 		} else
3996 			error = 0;
3997 	}
3998 
3999 	/*
4000 	 * len will be set to 0 upon a successful Copy RPC.
4001 	 * As such, this only loops when the Copy RPC needs to be retried.
4002 	 */
4003 	while (len > 0 && error == 0) {
4004 		inattrflag = outattrflag = 0;
4005 		len2 = len;
4006 		if (tryoutcred)
4007 			error = nfsrpc_copy_file_range(invp, ap->a_inoffp,
4008 			    outvp, ap->a_outoffp, &len2, ap->a_flags,
4009 			    &inattrflag, &innfsva, &outattrflag, &outnfsva,
4010 			    ap->a_outcred, consecutive, &must_commit);
4011 		else
4012 			error = nfsrpc_copy_file_range(invp, ap->a_inoffp,
4013 			    outvp, ap->a_outoffp, &len2, ap->a_flags,
4014 			    &inattrflag, &innfsva, &outattrflag, &outnfsva,
4015 			    ap->a_incred, consecutive, &must_commit);
4016 		if (inattrflag != 0)
4017 			ret = nfscl_loadattrcache(&invp, &innfsva, NULL, 0, 1);
4018 		if (outattrflag != 0)
4019 			ret2 = nfscl_loadattrcache(&outvp, &outnfsva, NULL,
4020 			    1, 1);
4021 		if (error == 0) {
4022 			if (consecutive == false) {
4023 				if (len2 == len) {
4024 					mtx_lock(&nmp->nm_mtx);
4025 					nmp->nm_privflag |=
4026 					    NFSMNTP_NOCONSECUTIVE;
4027 					mtx_unlock(&nmp->nm_mtx);
4028 				} else
4029 					error = NFSERR_OFFLOADNOREQS;
4030 			}
4031 			*ap->a_lenp = len2;
4032 			len = 0;
4033 			if (len2 > 0 && must_commit && error == 0)
4034 				error = ncl_commit(outvp, outoff, *ap->a_lenp,
4035 				    ap->a_outcred, curthread);
4036 			if (error == 0 && ret != 0)
4037 				error = ret;
4038 			if (error == 0 && ret2 != 0)
4039 				error = ret2;
4040 		} else if (error == NFSERR_OFFLOADNOREQS && consecutive) {
4041 			/*
4042 			 * Try consecutive == false, which is ok only if all
4043 			 * bytes are copied.
4044 			 * If only some bytes were copied when consecutive
4045 			 * is false, there is no way to know which bytes
4046 			 * still need to be written.
4047 			 */
4048 			consecutive = false;
4049 			error = 0;
4050 		} else if (error == NFSERR_ACCES && tryoutcred) {
4051 			/* Try again with incred. */
4052 			tryoutcred = false;
4053 			error = 0;
4054 		}
4055 		if (error == NFSERR_STALEWRITEVERF) {
4056 			/*
4057 			 * Server rebooted, so do it all again.
4058 			 */
4059 			*ap->a_inoffp = inoff;
4060 			*ap->a_outoffp = outoff;
4061 			len = *ap->a_lenp;
4062 			must_commit = false;
4063 			error = 0;
4064 		}
4065 	}
4066 	VOP_UNLOCK(invp);
4067 	VOP_UNLOCK(outvp);
4068 	if (mp != NULL)
4069 		vn_finished_write(mp);
4070 	if (error == NFSERR_NOTSUPP || error == NFSERR_OFFLOADNOREQS ||
4071 	    error == NFSERR_ACCES) {
4072 		/*
4073 		 * Unlike the NFSv4.2 Copy, vn_generic_copy_file_range() can
4074 		 * use a_incred for the read and a_outcred for the write, so
4075 		 * try this for NFSERR_ACCES failures for the Copy.
4076 		 * For NFSERR_NOTSUPP and NFSERR_OFFLOADNOREQS, the Copy can
4077 		 * never succeed, so disable it.
4078 		 */
4079 		if (error != NFSERR_ACCES) {
4080 			/* Can never do Copy on this mount. */
4081 			mtx_lock(&nmp->nm_mtx);
4082 			nmp->nm_privflag |= NFSMNTP_NOCOPY;
4083 			mtx_unlock(&nmp->nm_mtx);
4084 		}
4085 		*ap->a_inoffp = inoff;
4086 		*ap->a_outoffp = outoff;
4087 		error = vn_generic_copy_file_range(ap->a_invp, ap->a_inoffp,
4088 		    ap->a_outvp, ap->a_outoffp, ap->a_lenp, ap->a_flags,
4089 		    ap->a_incred, ap->a_outcred, ap->a_fsizetd);
4090 	} else if (error != 0)
4091 		*ap->a_lenp = 0;
4092 
4093 	if (error != 0)
4094 		error = nfscl_maperr(curthread, error, (uid_t)0, (gid_t)0);
4095 	return (error);
4096 }
4097 
4098 /*
4099  * nfs ioctl call
4100  */
4101 static int
4102 nfs_ioctl(struct vop_ioctl_args *ap)
4103 {
4104 	struct vnode *vp = ap->a_vp;
4105 	struct nfsvattr nfsva;
4106 	struct nfsmount *nmp;
4107 	int attrflag, content, error, ret;
4108 	bool eof = false;			/* shut up compiler. */
4109 
4110 	if (vp->v_type != VREG)
4111 		return (ENOTTY);
4112 	nmp = VFSTONFS(vp->v_mount);
4113 	if (!NFSHASNFSV4(nmp) || nmp->nm_minorvers < NFSV42_MINORVERSION) {
4114 		error = vop_stdioctl(ap);
4115 		return (error);
4116 	}
4117 
4118 	/* Do the actual NFSv4.2 RPC. */
4119 	switch (ap->a_command) {
4120 	case FIOSEEKDATA:
4121 		content = NFSV4CONTENT_DATA;
4122 		break;
4123 	case FIOSEEKHOLE:
4124 		content = NFSV4CONTENT_HOLE;
4125 		break;
4126 	default:
4127 		return (ENOTTY);
4128 	}
4129 
4130 	error = vn_lock(vp, LK_SHARED);
4131 	if (error != 0)
4132 		return (EBADF);
4133 	attrflag = 0;
4134 	if (*((off_t *)ap->a_data) >= VTONFS(vp)->n_size)
4135 		error = ENXIO;
4136 	else {
4137 		/*
4138 		 * Flush all writes, so that the server is up to date.
4139 		 * Although a Commit is not required, the commit argument
4140 		 * is set so that, for a pNFS File/Flexible File Layout
4141 		 * server, the LayoutCommit will be done to ensure the file
4142 		 * size is up to date on the Metadata Server.
4143 		 */
4144 		error = ncl_flush(vp, MNT_WAIT, ap->a_td, 1, 0);
4145 		if (error == 0)
4146 			error = nfsrpc_seek(vp, (off_t *)ap->a_data, &eof,
4147 			    content, ap->a_cred, &nfsva, &attrflag);
4148 		/* If at eof for FIOSEEKDATA, return ENXIO. */
4149 		if (eof && error == 0 && content == NFSV4CONTENT_DATA)
4150 			error = ENXIO;
4151 	}
4152 	if (attrflag != 0) {
4153 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
4154 		if (error == 0 && ret != 0)
4155 			error = ret;
4156 	}
4157 	NFSVOPUNLOCK(vp);
4158 
4159 	if (error != 0)
4160 		error = ENXIO;
4161 	return (error);
4162 }
4163 
4164 /*
4165  * nfs getextattr call
4166  */
4167 static int
4168 nfs_getextattr(struct vop_getextattr_args *ap)
4169 {
4170 	struct vnode *vp = ap->a_vp;
4171 	struct nfsmount *nmp;
4172 	struct ucred *cred;
4173 	struct thread *td = ap->a_td;
4174 	struct nfsvattr nfsva;
4175 	ssize_t len;
4176 	int attrflag, error, ret;
4177 
4178 	nmp = VFSTONFS(vp->v_mount);
4179 	mtx_lock(&nmp->nm_mtx);
4180 	if (!NFSHASNFSV4(nmp) || nmp->nm_minorvers < NFSV42_MINORVERSION ||
4181 	    (nmp->nm_privflag & NFSMNTP_NOXATTR) != 0 ||
4182 	    ap->a_attrnamespace != EXTATTR_NAMESPACE_USER) {
4183 		mtx_unlock(&nmp->nm_mtx);
4184 		return (EOPNOTSUPP);
4185 	}
4186 	mtx_unlock(&nmp->nm_mtx);
4187 
4188 	cred = ap->a_cred;
4189 	if (cred == NULL)
4190 		cred = td->td_ucred;
4191 	/* Do the actual NFSv4.2 Optional Extended Attribute (RFC-8276) RPC. */
4192 	attrflag = 0;
4193 	error = nfsrpc_getextattr(vp, ap->a_name, ap->a_uio, &len, &nfsva,
4194 	    &attrflag, cred, td);
4195 	if (attrflag != 0) {
4196 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
4197 		if (error == 0 && ret != 0)
4198 			error = ret;
4199 	}
4200 	if (error == 0 && ap->a_size != NULL)
4201 		*ap->a_size = len;
4202 
4203 	switch (error) {
4204 	case NFSERR_NOTSUPP:
4205 	case NFSERR_OPILLEGAL:
4206 		mtx_lock(&nmp->nm_mtx);
4207 		nmp->nm_privflag |= NFSMNTP_NOXATTR;
4208 		mtx_unlock(&nmp->nm_mtx);
4209 		error = EOPNOTSUPP;
4210 		break;
4211 	case NFSERR_NOXATTR:
4212 	case NFSERR_XATTR2BIG:
4213 		error = ENOATTR;
4214 		break;
4215 	default:
4216 		error = nfscl_maperr(td, error, 0, 0);
4217 		break;
4218 	}
4219 	return (error);
4220 }
4221 
4222 /*
4223  * nfs setextattr call
4224  */
4225 static int
4226 nfs_setextattr(struct vop_setextattr_args *ap)
4227 {
4228 	struct vnode *vp = ap->a_vp;
4229 	struct nfsmount *nmp;
4230 	struct ucred *cred;
4231 	struct thread *td = ap->a_td;
4232 	struct nfsvattr nfsva;
4233 	int attrflag, error, ret;
4234 
4235 	nmp = VFSTONFS(vp->v_mount);
4236 	mtx_lock(&nmp->nm_mtx);
4237 	if (!NFSHASNFSV4(nmp) || nmp->nm_minorvers < NFSV42_MINORVERSION ||
4238 	    (nmp->nm_privflag & NFSMNTP_NOXATTR) != 0 ||
4239 	    ap->a_attrnamespace != EXTATTR_NAMESPACE_USER) {
4240 		mtx_unlock(&nmp->nm_mtx);
4241 		return (EOPNOTSUPP);
4242 	}
4243 	mtx_unlock(&nmp->nm_mtx);
4244 
4245 	if (ap->a_uio->uio_resid < 0)
4246 		return (EINVAL);
4247 	cred = ap->a_cred;
4248 	if (cred == NULL)
4249 		cred = td->td_ucred;
4250 	/* Do the actual NFSv4.2 Optional Extended Attribute (RFC-8276) RPC. */
4251 	attrflag = 0;
4252 	error = nfsrpc_setextattr(vp, ap->a_name, ap->a_uio, &nfsva,
4253 	    &attrflag, cred, td);
4254 	if (attrflag != 0) {
4255 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
4256 		if (error == 0 && ret != 0)
4257 			error = ret;
4258 	}
4259 
4260 	switch (error) {
4261 	case NFSERR_NOTSUPP:
4262 	case NFSERR_OPILLEGAL:
4263 		mtx_lock(&nmp->nm_mtx);
4264 		nmp->nm_privflag |= NFSMNTP_NOXATTR;
4265 		mtx_unlock(&nmp->nm_mtx);
4266 		error = EOPNOTSUPP;
4267 		break;
4268 	case NFSERR_NOXATTR:
4269 	case NFSERR_XATTR2BIG:
4270 		error = ENOATTR;
4271 		break;
4272 	default:
4273 		error = nfscl_maperr(td, error, 0, 0);
4274 		break;
4275 	}
4276 	return (error);
4277 }
4278 
4279 /*
4280  * nfs listextattr call
4281  */
4282 static int
4283 nfs_listextattr(struct vop_listextattr_args *ap)
4284 {
4285 	struct vnode *vp = ap->a_vp;
4286 	struct nfsmount *nmp;
4287 	struct ucred *cred;
4288 	struct thread *td = ap->a_td;
4289 	struct nfsvattr nfsva;
4290 	size_t len, len2;
4291 	uint64_t cookie;
4292 	int attrflag, error, ret;
4293 	bool eof;
4294 
4295 	nmp = VFSTONFS(vp->v_mount);
4296 	mtx_lock(&nmp->nm_mtx);
4297 	if (!NFSHASNFSV4(nmp) || nmp->nm_minorvers < NFSV42_MINORVERSION ||
4298 	    (nmp->nm_privflag & NFSMNTP_NOXATTR) != 0 ||
4299 	    ap->a_attrnamespace != EXTATTR_NAMESPACE_USER) {
4300 		mtx_unlock(&nmp->nm_mtx);
4301 		return (EOPNOTSUPP);
4302 	}
4303 	mtx_unlock(&nmp->nm_mtx);
4304 
4305 	cred = ap->a_cred;
4306 	if (cred == NULL)
4307 		cred = td->td_ucred;
4308 
4309 	/* Loop around doing List Extended Attribute RPCs. */
4310 	eof = false;
4311 	cookie = 0;
4312 	len2 = 0;
4313 	error = 0;
4314 	while (!eof && error == 0) {
4315 		len = nmp->nm_rsize;
4316 		attrflag = 0;
4317 		error = nfsrpc_listextattr(vp, &cookie, ap->a_uio, &len, &eof,
4318 		    &nfsva, &attrflag, cred, td);
4319 		if (attrflag != 0) {
4320 			ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
4321 			if (error == 0 && ret != 0)
4322 				error = ret;
4323 		}
4324 		if (error == 0) {
4325 			len2 += len;
4326 			if (len2 > SSIZE_MAX)
4327 				error = ENOATTR;
4328 		}
4329 	}
4330 	if (error == 0 && ap->a_size != NULL)
4331 		*ap->a_size = len2;
4332 
4333 	switch (error) {
4334 	case NFSERR_NOTSUPP:
4335 	case NFSERR_OPILLEGAL:
4336 		mtx_lock(&nmp->nm_mtx);
4337 		nmp->nm_privflag |= NFSMNTP_NOXATTR;
4338 		mtx_unlock(&nmp->nm_mtx);
4339 		error = EOPNOTSUPP;
4340 		break;
4341 	case NFSERR_NOXATTR:
4342 	case NFSERR_XATTR2BIG:
4343 		error = ENOATTR;
4344 		break;
4345 	default:
4346 		error = nfscl_maperr(td, error, 0, 0);
4347 		break;
4348 	}
4349 	return (error);
4350 }
4351 
4352 /*
4353  * nfs setextattr call
4354  */
4355 static int
4356 nfs_deleteextattr(struct vop_deleteextattr_args *ap)
4357 {
4358 	struct vnode *vp = ap->a_vp;
4359 	struct nfsmount *nmp;
4360 	struct nfsvattr nfsva;
4361 	int attrflag, error, ret;
4362 
4363 	nmp = VFSTONFS(vp->v_mount);
4364 	mtx_lock(&nmp->nm_mtx);
4365 	if (!NFSHASNFSV4(nmp) || nmp->nm_minorvers < NFSV42_MINORVERSION ||
4366 	    (nmp->nm_privflag & NFSMNTP_NOXATTR) != 0 ||
4367 	    ap->a_attrnamespace != EXTATTR_NAMESPACE_USER) {
4368 		mtx_unlock(&nmp->nm_mtx);
4369 		return (EOPNOTSUPP);
4370 	}
4371 	mtx_unlock(&nmp->nm_mtx);
4372 
4373 	/* Do the actual NFSv4.2 Optional Extended Attribute (RFC-8276) RPC. */
4374 	attrflag = 0;
4375 	error = nfsrpc_rmextattr(vp, ap->a_name, &nfsva, &attrflag, ap->a_cred,
4376 	    ap->a_td);
4377 	if (attrflag != 0) {
4378 		ret = nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
4379 		if (error == 0 && ret != 0)
4380 			error = ret;
4381 	}
4382 
4383 	switch (error) {
4384 	case NFSERR_NOTSUPP:
4385 	case NFSERR_OPILLEGAL:
4386 		mtx_lock(&nmp->nm_mtx);
4387 		nmp->nm_privflag |= NFSMNTP_NOXATTR;
4388 		mtx_unlock(&nmp->nm_mtx);
4389 		error = EOPNOTSUPP;
4390 		break;
4391 	case NFSERR_NOXATTR:
4392 	case NFSERR_XATTR2BIG:
4393 		error = ENOATTR;
4394 		break;
4395 	default:
4396 		error = nfscl_maperr(ap->a_td, error, 0, 0);
4397 		break;
4398 	}
4399 	return (error);
4400 }
4401 
4402 /*
4403  * Return POSIX pathconf information applicable to nfs filesystems.
4404  */
4405 static int
4406 nfs_pathconf(struct vop_pathconf_args *ap)
4407 {
4408 	struct nfsv3_pathconf pc;
4409 	struct nfsvattr nfsva;
4410 	struct vnode *vp = ap->a_vp;
4411 	struct nfsmount *nmp;
4412 	struct thread *td = curthread;
4413 	off_t off;
4414 	bool eof;
4415 	int attrflag, error;
4416 
4417 	if ((NFS_ISV34(vp) && (ap->a_name == _PC_LINK_MAX ||
4418 	    ap->a_name == _PC_NAME_MAX || ap->a_name == _PC_CHOWN_RESTRICTED ||
4419 	    ap->a_name == _PC_NO_TRUNC)) ||
4420 	    (NFS_ISV4(vp) && ap->a_name == _PC_ACL_NFS4)) {
4421 		/*
4422 		 * Since only the above 4 a_names are returned by the NFSv3
4423 		 * Pathconf RPC, there is no point in doing it for others.
4424 		 * For NFSv4, the Pathconf RPC (actually a Getattr Op.) can
4425 		 * be used for _PC_NFS4_ACL as well.
4426 		 */
4427 		error = nfsrpc_pathconf(vp, &pc, td->td_ucred, td, &nfsva,
4428 		    &attrflag);
4429 		if (attrflag != 0)
4430 			(void) nfscl_loadattrcache(&vp, &nfsva, NULL, 0, 1);
4431 		if (error != 0)
4432 			return (error);
4433 	} else {
4434 		/*
4435 		 * For NFSv2 (or NFSv3 when not one of the above 4 a_names),
4436 		 * just fake them.
4437 		 */
4438 		pc.pc_linkmax = NFS_LINK_MAX;
4439 		pc.pc_namemax = NFS_MAXNAMLEN;
4440 		pc.pc_notrunc = 1;
4441 		pc.pc_chownrestricted = 1;
4442 		pc.pc_caseinsensitive = 0;
4443 		pc.pc_casepreserving = 1;
4444 		error = 0;
4445 	}
4446 	switch (ap->a_name) {
4447 	case _PC_LINK_MAX:
4448 #ifdef _LP64
4449 		*ap->a_retval = pc.pc_linkmax;
4450 #else
4451 		*ap->a_retval = MIN(LONG_MAX, pc.pc_linkmax);
4452 #endif
4453 		break;
4454 	case _PC_NAME_MAX:
4455 		*ap->a_retval = pc.pc_namemax;
4456 		break;
4457 	case _PC_PIPE_BUF:
4458 		if (ap->a_vp->v_type == VDIR || ap->a_vp->v_type == VFIFO)
4459 			*ap->a_retval = PIPE_BUF;
4460 		else
4461 			error = EINVAL;
4462 		break;
4463 	case _PC_CHOWN_RESTRICTED:
4464 		*ap->a_retval = pc.pc_chownrestricted;
4465 		break;
4466 	case _PC_NO_TRUNC:
4467 		*ap->a_retval = pc.pc_notrunc;
4468 		break;
4469 	case _PC_ACL_NFS4:
4470 		if (NFS_ISV4(vp) && nfsrv_useacl != 0 && attrflag != 0 &&
4471 		    NFSISSET_ATTRBIT(&nfsva.na_suppattr, NFSATTRBIT_ACL))
4472 			*ap->a_retval = 1;
4473 		else
4474 			*ap->a_retval = 0;
4475 		break;
4476 	case _PC_ACL_PATH_MAX:
4477 		if (NFS_ISV4(vp))
4478 			*ap->a_retval = ACL_MAX_ENTRIES;
4479 		else
4480 			*ap->a_retval = 3;
4481 		break;
4482 	case _PC_PRIO_IO:
4483 		*ap->a_retval = 0;
4484 		break;
4485 	case _PC_SYNC_IO:
4486 		*ap->a_retval = 0;
4487 		break;
4488 	case _PC_ALLOC_SIZE_MIN:
4489 		*ap->a_retval = vp->v_mount->mnt_stat.f_bsize;
4490 		break;
4491 	case _PC_FILESIZEBITS:
4492 		if (NFS_ISV34(vp))
4493 			*ap->a_retval = 64;
4494 		else
4495 			*ap->a_retval = 32;
4496 		break;
4497 	case _PC_REC_INCR_XFER_SIZE:
4498 		*ap->a_retval = vp->v_mount->mnt_stat.f_iosize;
4499 		break;
4500 	case _PC_REC_MAX_XFER_SIZE:
4501 		*ap->a_retval = -1; /* means ``unlimited'' */
4502 		break;
4503 	case _PC_REC_MIN_XFER_SIZE:
4504 		*ap->a_retval = vp->v_mount->mnt_stat.f_iosize;
4505 		break;
4506 	case _PC_REC_XFER_ALIGN:
4507 		*ap->a_retval = PAGE_SIZE;
4508 		break;
4509 	case _PC_SYMLINK_MAX:
4510 		*ap->a_retval = NFS_MAXPATHLEN;
4511 		break;
4512 	case _PC_MIN_HOLE_SIZE:
4513 		/* Only some NFSv4.2 servers support Seek for Holes. */
4514 		*ap->a_retval = 0;
4515 		nmp = VFSTONFS(vp->v_mount);
4516 		if (NFS_ISV4(vp) && nmp->nm_minorvers == NFSV42_MINORVERSION) {
4517 			/*
4518 			 * NFSv4.2 doesn't have an attribute for hole size,
4519 			 * so all we can do is see if the Seek operation is
4520 			 * supported and then use f_iosize as a "best guess".
4521 			 */
4522 			mtx_lock(&nmp->nm_mtx);
4523 			if ((nmp->nm_privflag & NFSMNTP_SEEKTESTED) == 0) {
4524 				mtx_unlock(&nmp->nm_mtx);
4525 				off = 0;
4526 				attrflag = 0;
4527 				error = nfsrpc_seek(vp, &off, &eof,
4528 				    NFSV4CONTENT_HOLE, td->td_ucred, &nfsva,
4529 				    &attrflag);
4530 				if (attrflag != 0)
4531 					nfscl_loadattrcache(&vp, &nfsva,
4532 					    NULL, 0, 1);
4533 				mtx_lock(&nmp->nm_mtx);
4534 				if (error == NFSERR_NOTSUPP)
4535 					nmp->nm_privflag |= NFSMNTP_SEEKTESTED;
4536 				else
4537 					nmp->nm_privflag |= NFSMNTP_SEEKTESTED |
4538 					    NFSMNTP_SEEK;
4539 				error = 0;
4540 			}
4541 			if ((nmp->nm_privflag & NFSMNTP_SEEK) != 0)
4542 				*ap->a_retval = vp->v_mount->mnt_stat.f_iosize;
4543 			mtx_unlock(&nmp->nm_mtx);
4544 		}
4545 		break;
4546 
4547 	default:
4548 		error = vop_stdpathconf(ap);
4549 		break;
4550 	}
4551 	return (error);
4552 }
4553