xref: /netbsd-src/sys/fs/unionfs/unionfs_vnops.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*-
2  * Copyright (c) 1992, 1993, 1994, 1995 Jan-Simon Pendry.
3  * Copyright (c) 1992, 1993, 1994, 1995
4  *      The Regents of the University of California.
5  * Copyright (c) 2005, 2006 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc.
6  * Copyright (c) 2006 Daichi Goto <daichi@freebsd.org>
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * Jan-Simon Pendry.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)union_vnops.c	8.32 (Berkeley) 6/23/95
37  * $FreeBSD: src/sys/fs/unionfs/union_vnops.c,v 1.152 2008/01/13 14:44:06 attilio Exp $
38  *
39  */
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/conf.h>
44 #include <sys/kernel.h>
45 #include <sys/lock.h>
46 #include <sys/malloc.h>
47 #include <sys/mount.h>
48 #include <sys/mutex.h>
49 #include <sys/namei.h>
50 #include <sys/sysctl.h>
51 #include <sys/vnode.h>
52 #include <sys/buf.h>
53 #include <sys/fcntl.h>
54 #include <sys/stat.h>
55 #include <sys/dirent.h>
56 #include <sys/proc.h>
57 
58 #include <fs/unionfs/unionfs.h>
59 
60 #if 0
61 #define UNIONFS_INTERNAL_DEBUG(msg, args...)    printf(msg, ## args)
62 #define UNIONFS_IDBG_RENAME
63 #else
64 #define UNIONFS_INTERNAL_DEBUG(msg, args...)
65 #endif
66 
67 static int
68 unionfs_lookup(void *v)
69 {
70 	struct vop_lookup_args *ap = v;
71 	int		iswhiteout;
72 	int		lockflag;
73 	int		error , uerror, lerror;
74 	u_long		nameiop;
75 	u_long		cnflags, cnflagsbk;
76 	struct unionfs_node *dunp;
77 	struct vnode   *dvp, *udvp, *ldvp, *vp, *uvp, *lvp, *dtmpvp;
78 	struct vattr	va;
79 	struct componentname *cnp;
80 
81 	iswhiteout = 0;
82 	lockflag = 0;
83 	error = uerror = lerror = ENOENT;
84 	cnp = ap->a_cnp;
85 	nameiop = cnp->cn_nameiop;
86 	cnflags = cnp->cn_flags;
87 	dvp = ap->a_dvp;
88 	dunp = VTOUNIONFS(dvp);
89 	udvp = dunp->un_uppervp;
90 	ldvp = dunp->un_lowervp;
91 	vp = uvp = lvp = NULLVP;
92 	*(ap->a_vpp) = NULLVP;
93 
94 	UNIONFS_INTERNAL_DEBUG("unionfs_lookup: enter: nameiop=%ld, flags=%lx, path=%s\n", nameiop, cnflags, cnp->cn_nameptr);
95 
96 	if (dvp->v_type != VDIR)
97 		return (ENOTDIR);
98 
99 	/*
100 	 * If read-only and op is not LOOKUP, will return EROFS.
101 	 */
102 	if ((cnflags & ISLASTCN) &&
103 	    (dvp->v_mount->mnt_flag & MNT_RDONLY) &&
104 	    LOOKUP != nameiop)
105 		return (EROFS);
106 
107 	/*
108 	 * lookup dotdot
109 	 */
110 	if (cnflags & ISDOTDOT) {
111 		if (LOOKUP != nameiop && udvp == NULLVP)
112 			return (EROFS);
113 
114 		if (udvp != NULLVP) {
115 			dtmpvp = udvp;
116 			if (ldvp != NULLVP)
117 				VOP_UNLOCK(ldvp);
118 		}
119 		else
120 			dtmpvp = ldvp;
121 
122 		error = VOP_LOOKUP(dtmpvp, &vp, cnp);
123 
124 		if (dtmpvp == udvp && ldvp != NULLVP) {
125 			VOP_UNLOCK(udvp);
126 			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
127 		}
128 
129 		if (error == 0) {
130 			/*
131 			 * Exchange lock and reference from vp to
132 			 * dunp->un_dvp. vp is upper/lower vnode, but it
133 			 * will need to return the unionfs vnode.
134 			 */
135 			if (nameiop == DELETE  || nameiop == RENAME)
136 				VOP_UNLOCK(vp);
137 			vrele(vp);
138 
139 			VOP_UNLOCK(dvp);
140 			*(ap->a_vpp) = dunp->un_dvp;
141 			vref(dunp->un_dvp);
142 
143 			vn_lock(dunp->un_dvp, LK_EXCLUSIVE | LK_RETRY);
144 			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
145 		} else if (error == ENOENT && nameiop != CREATE)
146 			cache_enter(dvp, NULLVP, cnp->cn_nameptr,
147 				    cnp->cn_namelen, cnp->cn_flags);
148 
149 		UNIONFS_INTERNAL_DEBUG("unionfs_lookup: leave (%d)\n", error);
150 
151 		return (error);
152 	}
153 
154 	/*
155 	 * lookup upper layer
156 	 */
157 	if (udvp != NULLVP) {
158 		uerror = VOP_LOOKUP(udvp, &uvp, cnp);
159 
160 		if (uerror == 0) {
161 			if (udvp == uvp) {	/* is dot */
162 				vrele(uvp);
163 				*(ap->a_vpp) = dvp;
164 				vref(dvp);
165 
166 				UNIONFS_INTERNAL_DEBUG("unionfs_lookup: leave (%d)\n", uerror);
167 
168 				return (uerror);
169 			}
170 		}
171 
172 		/* check whiteout */
173 		if (uerror == ENOENT || uerror == EJUSTRETURN)
174 			if (cnp->cn_flags & ISWHITEOUT)
175 				iswhiteout = 1;	/* don't lookup lower */
176 		if (iswhiteout == 0 && ldvp != NULLVP)
177 			if (VOP_GETATTR(udvp, &va, cnp->cn_cred) == 0 &&
178 			    (va.va_flags & OPAQUE))
179 				iswhiteout = 1;	/* don't lookup lower */
180 #if 0
181 		UNIONFS_INTERNAL_DEBUG("unionfs_lookup: debug: whiteout=%d, path=%s\n", iswhiteout, cnp->cn_nameptr);
182 #endif
183 	}
184 
185 	/*
186 	 * lookup lower layer
187 	 */
188 	if (ldvp != NULLVP && !(cnflags & DOWHITEOUT) && iswhiteout == 0) {
189 		/* always op is LOOKUP */
190 		cnp->cn_nameiop = LOOKUP;
191 		cnflagsbk = cnp->cn_flags;
192 		cnp->cn_flags = cnflags;
193 
194 		lerror = VOP_LOOKUP(ldvp, &lvp, cnp);
195 
196 		cnp->cn_nameiop = nameiop;
197 		if (udvp != NULLVP && (uerror == 0 || uerror == EJUSTRETURN))
198 			cnp->cn_flags = cnflagsbk;
199 
200 		if (lerror == 0) {
201 			if (ldvp == lvp) {	/* is dot */
202 				if (uvp != NULLVP)
203 					vrele(uvp);	/* no need? */
204 				vrele(lvp);
205 				*(ap->a_vpp) = dvp;
206 				vref(dvp);
207 
208 				UNIONFS_INTERNAL_DEBUG("unionfs_lookup: leave (%d)\n", lerror);
209 				if (uvp != NULL)
210 					VOP_UNLOCK(uvp);
211 				return (lerror);
212 			}
213 		}
214 	}
215 
216 	/*
217 	 * check lookup result
218 	 */
219 	if (uvp == NULLVP && lvp == NULLVP) {
220 		UNIONFS_INTERNAL_DEBUG("unionfs_lookup: leave (%d)\n",
221 		    (udvp != NULLVP ? uerror : lerror));
222 		return (udvp != NULLVP ? uerror : lerror);
223 	}
224 
225 	/*
226 	 * check vnode type
227 	 */
228 	if (uvp != NULLVP && lvp != NULLVP && uvp->v_type != lvp->v_type) {
229 		vput(lvp);
230 		lvp = NULLVP;
231 	}
232 
233 	/*
234 	 * check shadow dir
235 	 */
236 	if (uerror != 0 && uerror != EJUSTRETURN && udvp != NULLVP &&
237 	    lerror == 0 && lvp != NULLVP && lvp->v_type == VDIR &&
238 	    !(dvp->v_mount->mnt_flag & MNT_RDONLY) &&
239 	    (1 < cnp->cn_namelen || '.' != *(cnp->cn_nameptr))) {
240 		/* get unionfs vnode in order to create a new shadow dir. */
241 		error = unionfs_nodeget(dvp->v_mount, NULLVP, lvp, dvp, &vp,
242 		    cnp);
243 		if (error != 0)
244 			goto unionfs_lookup_out;
245 		error = unionfs_mkshadowdir(MOUNTTOUNIONFSMOUNT(dvp->v_mount),
246 		    udvp, VTOUNIONFS(vp), cnp);
247 		if (error != 0) {
248 			UNIONFSDEBUG("unionfs_lookup: Unable to create shadow dir.");
249 			vput(vp);
250 			goto unionfs_lookup_out;
251 		}
252 	}
253 	/*
254 	 * get unionfs vnode.
255 	 */
256 	else {
257 		if (uvp != NULLVP)
258 			error = uerror;
259 		else
260 			error = lerror;
261 		if (error != 0)
262 			goto unionfs_lookup_out;
263 		error = unionfs_nodeget(dvp->v_mount, uvp, lvp, dvp, &vp, cnp);
264 		if (error != 0) {
265 			UNIONFSDEBUG("unionfs_lookup: Unable to create unionfs vnode.");
266 			goto unionfs_lookup_out;
267 		}
268 	}
269 
270 	*(ap->a_vpp) = vp;
271 
272 	cache_enter(dvp, vp, cnp->cn_nameptr, cnp->cn_namelen,
273 		    cnp->cn_flags);
274 
275 	/* XXXAD lock status on error */
276 unionfs_lookup_out:
277 	if (uvp != NULLVP)
278 		vrele(uvp);
279 	if (lvp != NULLVP)
280 		vrele(lvp);
281 
282 	if (error == ENOENT && nameiop != CREATE)
283 		cache_enter(dvp, NULLVP, cnp->cn_nameptr, cnp->cn_namelen,
284 			    cnp->cn_flags);
285 
286 	UNIONFS_INTERNAL_DEBUG("unionfs_lookup: leave (%d)\n", error);
287 
288 	return (error);
289 }
290 
291 static int
292 unionfs_create(void *v)
293 {
294 	struct vop_create_args *ap = v;
295 	struct unionfs_node *dunp;
296 	struct componentname *cnp;
297 	struct vnode   *udvp;
298 	struct vnode   *vp;
299 	int		error;
300 
301 	UNIONFS_INTERNAL_DEBUG("unionfs_create: enter\n");
302 
303 	dunp = VTOUNIONFS(ap->a_dvp);
304 	cnp = ap->a_cnp;
305 	udvp = dunp->un_uppervp;
306 	error = EROFS;
307 
308 	if (udvp != NULLVP) {
309 		if ((error = VOP_CREATE(udvp, &vp, cnp, ap->a_vap)) == 0) {
310 			error = unionfs_nodeget(ap->a_dvp->v_mount, vp, NULLVP,
311 			    ap->a_dvp, ap->a_vpp, cnp);
312 			if (error) {
313 				vput(vp);
314 			} else {
315 				vrele(vp);
316 			}
317 		}
318 	}
319 
320 	UNIONFS_INTERNAL_DEBUG("unionfs_create: leave (%d)\n", error);
321 
322 	return (error);
323 }
324 
325 static int
326 unionfs_whiteout(void *v)
327 {
328 	struct vop_whiteout_args *ap = v;
329 	struct unionfs_node *dunp;
330 	struct componentname *cnp;
331 	struct vnode   *udvp;
332 	int		error;
333 
334 	UNIONFS_INTERNAL_DEBUG("unionfs_whiteout: enter\n");
335 
336 	dunp = VTOUNIONFS(ap->a_dvp);
337 	cnp = ap->a_cnp;
338 	udvp = dunp->un_uppervp;
339 	error = EOPNOTSUPP;
340 
341 	if (udvp != NULLVP) {
342 		switch (ap->a_flags) {
343 		case CREATE:
344 		case DELETE:
345 		case LOOKUP:
346 			error = VOP_WHITEOUT(udvp, cnp, ap->a_flags);
347 			break;
348 		default:
349 			error = EINVAL;
350 			break;
351 		}
352 	}
353 
354 	UNIONFS_INTERNAL_DEBUG("unionfs_whiteout: leave (%d)\n", error);
355 
356 	return (error);
357 }
358 
359 static int
360 unionfs_mknod(void *v)
361 {
362 	struct vop_mknod_args *ap = v;
363 	struct unionfs_node *dunp;
364 	struct componentname *cnp;
365 	struct vnode   *udvp;
366 	struct vnode   *vp;
367 	int		error;
368 
369 	UNIONFS_INTERNAL_DEBUG("unionfs_mknod: enter\n");
370 
371 	dunp = VTOUNIONFS(ap->a_dvp);
372 	cnp = ap->a_cnp;
373 	udvp = dunp->un_uppervp;
374 	error = EROFS;
375 
376 	if (udvp != NULLVP) {
377 		if ((error = VOP_MKNOD(udvp, &vp, cnp, ap->a_vap)) == 0) {
378 			error = unionfs_nodeget(ap->a_dvp->v_mount, vp, NULLVP,
379 			    ap->a_dvp, ap->a_vpp, cnp);
380 			if (error) {
381 				vput(vp);
382 			} else {
383 				vrele(vp);
384 			}
385 		}
386 	}
387 
388 	UNIONFS_INTERNAL_DEBUG("unionfs_mknod: leave (%d)\n", error);
389 
390 	return (error);
391 }
392 
393 static int
394 unionfs_open(void *v)
395 {
396 	struct vop_open_args *ap = v;
397 	int		error;
398 	struct unionfs_node *unp;
399 	struct unionfs_node_status *unsp;
400 	struct vnode   *uvp;
401 	struct vnode   *lvp;
402 	struct vnode   *targetvp;
403 	kauth_cred_t   cred;
404 
405 	UNIONFS_INTERNAL_DEBUG("unionfs_open: enter\n");
406 
407 	error = 0;
408 	unp = VTOUNIONFS(ap->a_vp);
409 	uvp = unp->un_uppervp;
410 	lvp = unp->un_lowervp;
411 	targetvp = NULLVP;
412 	cred = ap->a_cred;
413 
414 	unionfs_get_node_status(unp, &unsp);
415 
416 	if (unsp->uns_lower_opencnt > 0 || unsp->uns_upper_opencnt > 0) {
417 		/* vnode is already opend. */
418 		if (unsp->uns_upper_opencnt > 0)
419 			targetvp = uvp;
420 		else
421 			targetvp = lvp;
422 
423 		if (targetvp == lvp &&
424 		    (ap->a_mode & FWRITE) && lvp->v_type == VREG)
425 			targetvp = NULLVP;
426 	}
427 	if (targetvp == NULLVP) {
428 		if (uvp == NULLVP) {
429 			if ((ap->a_mode & FWRITE) && lvp->v_type == VREG) {
430 				error = unionfs_copyfile(unp,
431 				    !(ap->a_mode & O_TRUNC), cred);
432 				if (error != 0)
433 					goto unionfs_open_abort;
434 				targetvp = uvp = unp->un_uppervp;
435 			} else
436 				targetvp = lvp;
437 		} else
438 			targetvp = uvp;
439 	}
440 
441 	error = VOP_OPEN(targetvp, ap->a_mode, cred);
442 	if (error == 0) {
443 		if (targetvp == uvp) {
444 			if (uvp->v_type == VDIR && lvp != NULLVP &&
445 			    unsp->uns_lower_opencnt <= 0) {
446 				/* open lower for readdir */
447 				error = VOP_OPEN(lvp, FREAD, cred);
448 				if (error != 0) {
449 					VOP_CLOSE(uvp, ap->a_mode, cred);
450 					goto unionfs_open_abort;
451 				}
452 				unsp->uns_node_flag |= UNS_OPENL_4_READDIR;
453 				unsp->uns_lower_opencnt++;
454 			}
455 			unsp->uns_upper_opencnt++;
456 		} else {
457 			unsp->uns_lower_opencnt++;
458 			unsp->uns_lower_openmode = ap->a_mode;
459 		}
460 	}
461 
462 unionfs_open_abort:
463 	if (error != 0)
464 		unionfs_tryrem_node_status(unp, unsp);
465 
466 	UNIONFS_INTERNAL_DEBUG("unionfs_open: leave (%d)\n", error);
467 
468 	return (error);
469 }
470 
471 static int
472 unionfs_close(void *v)
473 {
474 	struct vop_close_args *ap = v;
475 	int		error;
476 	struct unionfs_node *unp;
477 	struct unionfs_node_status *unsp;
478 	kauth_cred_t   cred;
479 	struct vnode   *ovp;
480 
481 	UNIONFS_INTERNAL_DEBUG("unionfs_close: enter\n");
482 
483 	KASSERT(VOP_ISLOCKED(ap->a_vp) == LK_EXCLUSIVE);
484 	unp = VTOUNIONFS(ap->a_vp);
485 	cred = ap->a_cred;
486 
487 	unionfs_get_node_status(unp, &unsp);
488 
489 	if (unsp->uns_lower_opencnt <= 0 && unsp->uns_upper_opencnt <= 0) {
490 #ifdef DIAGNOSTIC
491 		printf("unionfs_close: warning: open count is 0\n");
492 #endif
493 		if (unp->un_uppervp != NULLVP)
494 			ovp = unp->un_uppervp;
495 		else
496 			ovp = unp->un_lowervp;
497 	} else if (unsp->uns_upper_opencnt > 0)
498 		ovp = unp->un_uppervp;
499 	else
500 		ovp = unp->un_lowervp;
501 
502 	error = VOP_CLOSE(ovp, ap->a_fflag, cred);
503 
504 	if (error != 0)
505 		goto unionfs_close_abort;
506 
507 	if (ovp == unp->un_uppervp) {
508 		unsp->uns_upper_opencnt--;
509 		if (unsp->uns_upper_opencnt == 0) {
510 			if (unsp->uns_node_flag & UNS_OPENL_4_READDIR) {
511 				VOP_CLOSE(unp->un_lowervp, FREAD, cred);
512 				unsp->uns_node_flag &= ~UNS_OPENL_4_READDIR;
513 				unsp->uns_lower_opencnt--;
514 			}
515 		}
516 	} else
517 		unsp->uns_lower_opencnt--;
518 
519 unionfs_close_abort:
520 	unionfs_tryrem_node_status(unp, unsp);
521 
522 	UNIONFS_INTERNAL_DEBUG("unionfs_close: leave (%d)\n", error);
523 
524 	return (error);
525 }
526 
527 /*
528  * Check the access mode toward shadow file/dir.
529  */
530 static int
531 unionfs_check_corrected_access(u_short mode, struct vattr *va, kauth_cred_t cred)
532 {
533 	int		result;
534 	int		error;
535 	uid_t		uid;	/* upper side vnode's uid */
536 	gid_t		gid;	/* upper side vnode's gid */
537 	u_short		vmode;	/* upper side vnode's mode */
538 	u_short		mask;
539 
540 	mask = 0;
541 	uid = va->va_uid;
542 	gid = va->va_gid;
543 	vmode = va->va_mode;
544 
545 	/* check owner */
546 	if (kauth_cred_getuid(cred) == uid) {
547 		if (mode & VEXEC)
548 			mask |= S_IXUSR;
549 		if (mode & VREAD)
550 			mask |= S_IRUSR;
551 		if (mode & VWRITE)
552 			mask |= S_IWUSR;
553 		return ((vmode & mask) == mask ? 0 : EACCES);
554 	}
555 
556 	/* check group */
557 	error = kauth_cred_ismember_gid(cred, gid, &result);
558 	if (error != 0)
559 		return error;
560 	if (result) {
561 		if (mode & VEXEC)
562 			mask |= S_IXGRP;
563 		if (mode & VREAD)
564 			mask |= S_IRGRP;
565 		if (mode & VWRITE)
566 			mask |= S_IWGRP;
567 		return ((vmode & mask) == mask ? 0 : EACCES);
568 	}
569 
570 	/* check other */
571 	if (mode & VEXEC)
572 		mask |= S_IXOTH;
573 	if (mode & VREAD)
574 		mask |= S_IROTH;
575 	if (mode & VWRITE)
576 		mask |= S_IWOTH;
577 
578 	return ((vmode & mask) == mask ? 0 : EACCES);
579 }
580 
581 static int
582 unionfs_access(void *v)
583 {
584 	struct vop_access_args *ap = v;
585 	struct unionfs_mount *ump;
586 	struct unionfs_node *unp;
587 	struct vnode   *uvp;
588 	struct vnode   *lvp;
589 	struct vattr	va;
590 	int		mode;
591 	int		error;
592 
593 	UNIONFS_INTERNAL_DEBUG("unionfs_access: enter\n");
594 
595 	ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount);
596 	unp = VTOUNIONFS(ap->a_vp);
597 	uvp = unp->un_uppervp;
598 	lvp = unp->un_lowervp;
599 	mode = ap->a_mode;
600 	error = EACCES;
601 
602 	if ((mode & VWRITE) &&
603 	    (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)) {
604 		switch (ap->a_vp->v_type) {
605 		case VREG:
606 		case VDIR:
607 		case VLNK:
608 			return (EROFS);
609 		default:
610 			break;
611 		}
612 	}
613 
614 	if (uvp != NULLVP) {
615 		error = VOP_ACCESS(uvp, mode, ap->a_cred);
616 
617 		UNIONFS_INTERNAL_DEBUG("unionfs_access: leave (%d)\n", error);
618 
619 		return (error);
620 	}
621 
622 	if (lvp != NULLVP) {
623 		if (mode & VWRITE) {
624 			if (ump->um_uppervp->v_mount->mnt_flag & MNT_RDONLY) {
625 				switch (ap->a_vp->v_type) {
626 				case VREG:
627 				case VDIR:
628 				case VLNK:
629 					return (EROFS);
630 				default:
631 					break;
632 				}
633 			} else if (ap->a_vp->v_type == VREG || ap->a_vp->v_type == VDIR) {
634 				/* check shadow file/dir */
635 				if (ump->um_copymode != UNIONFS_TRANSPARENT) {
636 					error = unionfs_create_uppervattr(ump,
637 					    lvp, &va, ap->a_cred);
638 					if (error != 0)
639 						return (error);
640 
641 					error = unionfs_check_corrected_access(
642 					    mode, &va, ap->a_cred);
643 					if (error != 0)
644 						return (error);
645 				}
646 			}
647 			mode &= ~VWRITE;
648 			mode |= VREAD; /* will copy to upper */
649 		}
650 		error = VOP_ACCESS(lvp, mode, ap->a_cred);
651 	}
652 
653 	UNIONFS_INTERNAL_DEBUG("unionfs_access: leave (%d)\n", error);
654 
655 	return (error);
656 }
657 
658 static int
659 unionfs_getattr(void *v)
660 {
661 	struct vop_getattr_args *ap = v;
662 	int		error;
663 	struct unionfs_node *unp;
664 	struct unionfs_mount *ump;
665 	struct vnode   *uvp;
666 	struct vnode   *lvp;
667 	struct vattr	va;
668 
669 	UNIONFS_INTERNAL_DEBUG("unionfs_getattr: enter\n");
670 
671 	unp = VTOUNIONFS(ap->a_vp);
672 	ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount);
673 	uvp = unp->un_uppervp;
674 	lvp = unp->un_lowervp;
675 
676 	if (uvp != NULLVP) {
677 		if ((error = VOP_GETATTR(uvp, ap->a_vap, ap->a_cred)) == 0)
678 			ap->a_vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid;
679 
680 		UNIONFS_INTERNAL_DEBUG("unionfs_getattr: leave mode=%o, uid=%d, gid=%d (%d)\n",
681 		    ap->a_vap->va_mode, ap->a_vap->va_uid,
682 		    ap->a_vap->va_gid, error);
683 
684 		return (error);
685 	}
686 
687 	error = VOP_GETATTR(lvp, ap->a_vap, ap->a_cred);
688 
689 	if (error == 0 && !(ump->um_uppervp->v_mount->mnt_flag & MNT_RDONLY)) {
690 		/* correct the attr toward shadow file/dir. */
691 		if (ap->a_vp->v_type == VREG || ap->a_vp->v_type == VDIR) {
692 			unionfs_create_uppervattr_core(ump, ap->a_vap, &va);
693 			ap->a_vap->va_mode = va.va_mode;
694 			ap->a_vap->va_uid = va.va_uid;
695 			ap->a_vap->va_gid = va.va_gid;
696 		}
697 	}
698 
699 	if (error == 0)
700 		ap->a_vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid;
701 
702 	UNIONFS_INTERNAL_DEBUG("unionfs_getattr: leave mode=%o, uid=%d, gid=%d (%d)\n",
703 	    ap->a_vap->va_mode, ap->a_vap->va_uid, ap->a_vap->va_gid, error);
704 
705 	return (error);
706 }
707 
708 static int
709 unionfs_setattr(void *v)
710 {
711 	struct vop_setattr_args *ap = v;
712 	int		error;
713 	struct unionfs_node *unp;
714 	struct vnode   *uvp;
715 	struct vnode   *lvp;
716 	struct vattr   *vap;
717 
718 	UNIONFS_INTERNAL_DEBUG("unionfs_setattr: enter\n");
719 
720 	error = EROFS;
721 	unp = VTOUNIONFS(ap->a_vp);
722 	uvp = unp->un_uppervp;
723 	lvp = unp->un_lowervp;
724 	vap = ap->a_vap;
725 
726 	if ((ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) &&
727 	    (vap->va_flags != VNOVAL || vap->va_uid != (uid_t)VNOVAL ||
728 	     vap->va_gid != (gid_t)VNOVAL || vap->va_atime.tv_sec != VNOVAL ||
729 	     vap->va_mtime.tv_sec != VNOVAL || vap->va_mode != (mode_t)VNOVAL))
730 		return (EROFS);
731 
732 	if (uvp == NULLVP && lvp->v_type == VREG) {
733 		error = unionfs_copyfile(unp, (vap->va_size != 0),
734 		    ap->a_cred);
735 		if (error != 0)
736 			return (error);
737 		uvp = unp->un_uppervp;
738 	}
739 
740 	if (uvp != NULLVP)
741 		error = VOP_SETATTR(uvp, vap, ap->a_cred);
742 
743 	UNIONFS_INTERNAL_DEBUG("unionfs_setattr: leave (%d)\n", error);
744 
745 	return (error);
746 }
747 
748 static int
749 unionfs_read(void *v)
750 {
751 	struct vop_read_args *ap = v;
752 	int		error;
753 	struct unionfs_node *unp;
754 	struct vnode   *tvp;
755 
756 	/* UNIONFS_INTERNAL_DEBUG("unionfs_read: enter\n"); */
757 
758 	unp = VTOUNIONFS(ap->a_vp);
759 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
760 
761 	error = VOP_READ(tvp, ap->a_uio, ap->a_ioflag, ap->a_cred);
762 
763 	/* UNIONFS_INTERNAL_DEBUG("unionfs_read: leave (%d)\n", error); */
764 
765 	return (error);
766 }
767 
768 static int
769 unionfs_write(void *v)
770 {
771 	struct vop_write_args *ap = v;
772 	int		error;
773 	struct unionfs_node *unp;
774 	struct vnode   *tvp;
775 
776 	/* UNIONFS_INTERNAL_DEBUG("unionfs_write: enter\n"); */
777 
778 	unp = VTOUNIONFS(ap->a_vp);
779 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
780 
781 	error = VOP_WRITE(tvp, ap->a_uio, ap->a_ioflag, ap->a_cred);
782 
783 	/* UNIONFS_INTERNAL_DEBUG("unionfs_write: leave (%d)\n", error); */
784 
785 	return (error);
786 }
787 
788 static int
789 unionfs_ioctl(void *v)
790 {
791 	struct vop_ioctl_args *ap = v;
792 	int error;
793 	struct unionfs_node *unp;
794 	struct unionfs_node_status *unsp;
795 	struct vnode   *ovp;
796 
797 	UNIONFS_INTERNAL_DEBUG("unionfs_ioctl: enter\n");
798 
799  	vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY);
800 	unp = VTOUNIONFS(ap->a_vp);
801 	unionfs_get_node_status(unp, &unsp);
802 	ovp = (unsp->uns_upper_opencnt ? unp->un_uppervp : unp->un_lowervp);
803 	unionfs_tryrem_node_status(unp, unsp);
804 	VOP_UNLOCK(ap->a_vp);
805 
806 	if (ovp == NULLVP)
807 		return (EBADF);
808 
809 	error = VOP_IOCTL(ovp, ap->a_command, ap->a_data, ap->a_fflag,
810 	    ap->a_cred);
811 
812 	UNIONFS_INTERNAL_DEBUG("unionfs_ioctl: lease (%d)\n", error);
813 
814 	return (error);
815 }
816 
817 static int
818 unionfs_poll(void *v)
819 {
820 	struct vop_poll_args *ap = v;
821 	struct unionfs_node *unp;
822 	struct unionfs_node_status *unsp;
823 	struct vnode   *ovp;
824 
825  	vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY);
826 	unp = VTOUNIONFS(ap->a_vp);
827 	unionfs_get_node_status(unp, &unsp);
828 	ovp = (unsp->uns_upper_opencnt ? unp->un_uppervp : unp->un_lowervp);
829 	unionfs_tryrem_node_status(unp, unsp);
830 	VOP_UNLOCK(ap->a_vp);
831 
832 	if (ovp == NULLVP)
833 		return (EBADF);
834 
835 	return (VOP_POLL(ovp, ap->a_events));
836 }
837 
838 static int
839 unionfs_fsync(void *v)
840 {
841 	struct vop_fsync_args *ap = v;
842 	struct unionfs_node *unp;
843 	struct unionfs_node_status *unsp;
844 	struct vnode   *ovp;
845 
846 	unp = VTOUNIONFS(ap->a_vp);
847 	unionfs_get_node_status(unp, &unsp);
848 	ovp = (unsp->uns_upper_opencnt ? unp->un_uppervp : unp->un_lowervp);
849 	unionfs_tryrem_node_status(unp, unsp);
850 
851 	if (ovp == NULLVP)
852 		return (EBADF);
853 
854 	return (VOP_FSYNC(ovp, ap->a_cred, ap->a_flags, ap->a_offlo, ap->a_offhi));
855 }
856 
857 static int
858 unionfs_remove(void *v)
859 {
860 	struct vop_remove_v2_args *ap = v;
861 	int		error;
862 	struct unionfs_node *dunp;
863 	struct unionfs_node *unp;
864 	struct unionfs_mount *ump;
865 	struct vnode   *udvp;
866 	struct vnode   *uvp;
867 	struct vnode   *lvp;
868 	struct componentname *cnp;
869 
870 	UNIONFS_INTERNAL_DEBUG("unionfs_remove: enter\n");
871 
872 	error = 0;
873 	dunp = VTOUNIONFS(ap->a_dvp);
874 	unp = VTOUNIONFS(ap->a_vp);
875 	udvp = dunp->un_uppervp;
876 	uvp = unp->un_uppervp;
877 	lvp = unp->un_lowervp;
878 	cnp = ap->a_cnp;
879 
880 	if (udvp == NULLVP) {
881 		vput(ap->a_vp);
882 		return (EROFS);
883 	}
884 
885 	if (uvp != NULLVP) {
886 		ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount);
887 		if (ump->um_whitemode == UNIONFS_WHITE_ALWAYS || lvp != NULLVP)
888 			cnp->cn_flags |= DOWHITEOUT;
889 		error = VOP_REMOVE(udvp, uvp, cnp);
890 	} else if (lvp != NULLVP)
891 		error = unionfs_mkwhiteout(udvp, cnp, unp->un_path);
892 
893 	UNIONFS_INTERNAL_DEBUG("unionfs_remove: leave (%d)\n", error);
894 
895 	return (error);
896 }
897 
898 static int
899 unionfs_link(void *v)
900 {
901 #if 0
902 	struct vop_link_v2_args *ap = v;
903 	int		error;
904 	int		needrelookup;
905 	struct unionfs_node *dunp;
906 	struct unionfs_node *unp;
907 	struct vnode   *udvp;
908 	struct vnode   *uvp;
909 	struct componentname *cnp;
910 
911 	UNIONFS_INTERNAL_DEBUG("unionfs_link: enter\n");
912 
913 	error = 0;
914 	needrelookup = 0;
915 	dunp = VTOUNIONFS(ap->a_tdvp);
916 	unp = NULL;
917 	udvp = dunp->un_uppervp;
918 	uvp = NULLVP;
919 	cnp = ap->a_cnp;
920 
921 	if (udvp == NULLVP)
922 		return (EROFS);
923 
924 	if (ap->a_vp->v_op != unionfs_vnodeop_p)
925 		uvp = ap->a_vp;
926 	else {
927 		unp = VTOUNIONFS(ap->a_vp);
928 
929 		if (unp->un_uppervp == NULLVP) {
930 			if (ap->a_vp->v_type != VREG)
931 				return (EOPNOTSUPP);
932 
933 			error = unionfs_copyfile(unp, 1, cnp->cn_cred);
934 			if (error != 0)
935 				return (error);
936 			needrelookup = 1;
937 		}
938 		uvp = unp->un_uppervp;
939 	}
940 
941 	if (needrelookup != 0)
942 		error = unionfs_relookup_for_create(ap->a_tdvp, cnp);
943 
944 	if (error == 0)
945 		error = VOP_LINK(udvp, uvp, cnp);
946 
947 	UNIONFS_INTERNAL_DEBUG("unionfs_link: leave (%d)\n", error);
948 
949 	return (error);
950 #else
951 	panic("XXXAD");
952 	return 0;
953 #endif
954 }
955 
956 static int
957 unionfs_rename(void *v)
958 {
959 	struct vop_rename_args *ap = v;
960 	int		error;
961 	struct vnode   *fdvp;
962 	struct vnode   *fvp;
963 	struct componentname *fcnp;
964 	struct vnode   *tdvp;
965 	struct vnode   *tvp;
966 	struct componentname *tcnp;
967 	struct vnode   *ltdvp;
968 	struct vnode   *ltvp;
969 
970 	/* rename target vnodes */
971 	struct vnode   *rfdvp;
972 	struct vnode   *rfvp;
973 	struct vnode   *rtdvp;
974 	struct vnode   *rtvp;
975 
976 	int		needrelookup;
977 	struct unionfs_mount *ump;
978 	struct unionfs_node *unp;
979 
980 	UNIONFS_INTERNAL_DEBUG("unionfs_rename: enter\n");
981 
982 	error = 0;
983 	fdvp = ap->a_fdvp;
984 	fvp = ap->a_fvp;
985 	fcnp = ap->a_fcnp;
986 	tdvp = ap->a_tdvp;
987 	tvp = ap->a_tvp;
988 	tcnp = ap->a_tcnp;
989 	ltdvp = NULLVP;
990 	ltvp = NULLVP;
991 	rfdvp = fdvp;
992 	rfvp = fvp;
993 	rtdvp = tdvp;
994 	rtvp = tvp;
995 	needrelookup = 0;
996 
997 	/* check for cross device rename */
998 	if (fvp->v_mount != tdvp->v_mount ||
999 	    (tvp != NULLVP && fvp->v_mount != tvp->v_mount)) {
1000 		error = EXDEV;
1001 		goto unionfs_rename_abort;
1002 	}
1003 
1004 	/* Renaming a file to itself has no effect. */
1005 	if (fvp == tvp)
1006 		goto unionfs_rename_abort;
1007 
1008 	/*
1009 	 * from/to vnode is unionfs node.
1010 	 */
1011 
1012 	unp = VTOUNIONFS(fdvp);
1013 #ifdef UNIONFS_IDBG_RENAME
1014 	UNIONFS_INTERNAL_DEBUG("fdvp=%p, ufdvp=%p, lfdvp=%p\n", fdvp, unp->un_uppervp, unp->un_lowervp);
1015 #endif
1016 	if (unp->un_uppervp == NULLVP) {
1017 		error = ENODEV;
1018 		goto unionfs_rename_abort;
1019 	}
1020 	rfdvp = unp->un_uppervp;
1021 	vref(rfdvp);
1022 
1023 	unp = VTOUNIONFS(fvp);
1024 #ifdef UNIONFS_IDBG_RENAME
1025 	UNIONFS_INTERNAL_DEBUG("fvp=%p, ufvp=%p, lfvp=%p\n", fvp, unp->un_uppervp, unp->un_lowervp);
1026 #endif
1027 	ump = MOUNTTOUNIONFSMOUNT(fvp->v_mount);
1028 	if (unp->un_uppervp == NULLVP) {
1029 		switch (fvp->v_type) {
1030 		case VREG:
1031 			if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
1032 				goto unionfs_rename_abort;
1033 			error = unionfs_copyfile(unp, 1, fcnp->cn_cred);
1034 			VOP_UNLOCK(fvp);
1035 			if (error != 0)
1036 				goto unionfs_rename_abort;
1037 			break;
1038 		case VDIR:
1039 			if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
1040 				goto unionfs_rename_abort;
1041 			error = unionfs_mkshadowdir(ump, rfdvp, unp, fcnp);
1042 			VOP_UNLOCK(fvp);
1043 			if (error != 0)
1044 				goto unionfs_rename_abort;
1045 			break;
1046 		default:
1047 			error = ENODEV;
1048 			goto unionfs_rename_abort;
1049 		}
1050 
1051 		needrelookup = 1;
1052 	}
1053 
1054 	if (unp->un_lowervp != NULLVP)
1055 		fcnp->cn_flags |= DOWHITEOUT;
1056 	rfvp = unp->un_uppervp;
1057 	vref(rfvp);
1058 
1059 	unp = VTOUNIONFS(tdvp);
1060 #ifdef UNIONFS_IDBG_RENAME
1061 	UNIONFS_INTERNAL_DEBUG("tdvp=%p, utdvp=%p, ltdvp=%p\n", tdvp, unp->un_uppervp, unp->un_lowervp);
1062 #endif
1063 	if (unp->un_uppervp == NULLVP) {
1064 		error = ENODEV;
1065 		goto unionfs_rename_abort;
1066 	}
1067 	rtdvp = unp->un_uppervp;
1068 	ltdvp = unp->un_lowervp;
1069 	vref(rtdvp);
1070 
1071 	if (tdvp == tvp) {
1072 		rtvp = rtdvp;
1073 		vref(rtvp);
1074 	} else if (tvp != NULLVP) {
1075 		unp = VTOUNIONFS(tvp);
1076 #ifdef UNIONFS_IDBG_RENAME
1077 		UNIONFS_INTERNAL_DEBUG("tvp=%p, utvp=%p, ltvp=%p\n", tvp, unp->un_uppervp, unp->un_lowervp);
1078 #endif
1079 		if (unp->un_uppervp == NULLVP)
1080 			rtvp = NULLVP;
1081 		else {
1082 			if (tvp->v_type == VDIR) {
1083 				error = EINVAL;
1084 				goto unionfs_rename_abort;
1085 			}
1086 			rtvp = unp->un_uppervp;
1087 			ltvp = unp->un_lowervp;
1088 			vref(rtvp);
1089 		}
1090 	}
1091 
1092 	if (needrelookup != 0) {
1093 		if ((error = vn_lock(fdvp, LK_EXCLUSIVE)) != 0)
1094 			goto unionfs_rename_abort;
1095 		error = unionfs_relookup_for_delete(fdvp, fcnp);
1096 		VOP_UNLOCK(fdvp);
1097 		if (error != 0)
1098 			goto unionfs_rename_abort;
1099 
1100 		/* Locke of tvp is canceled in order to avoid recursive lock. */
1101 		if (tvp != NULLVP && tvp != tdvp)
1102 			VOP_UNLOCK(tvp);
1103 		error = unionfs_relookup_for_rename(tdvp, tcnp);
1104 		if (tvp != NULLVP && tvp != tdvp)
1105 			vn_lock(tvp, LK_EXCLUSIVE | LK_RETRY);
1106 		if (error != 0)
1107 			goto unionfs_rename_abort;
1108 	}
1109 
1110 	error = VOP_RENAME(rfdvp, rfvp, fcnp, rtdvp, rtvp, tcnp);
1111 
1112 	if (error == 0) {
1113 		if (rtvp != NULLVP && rtvp->v_type == VDIR)
1114 			cache_purge(tdvp);
1115 		if (fvp->v_type == VDIR && fdvp != tdvp)
1116 			cache_purge(fdvp);
1117 	}
1118 
1119 	if (fdvp != rfdvp)
1120 		vrele(fdvp);
1121 	if (fvp != rfvp)
1122 		vrele(fvp);
1123 	if (ltdvp != NULLVP)
1124 		VOP_UNLOCK(ltdvp);
1125 	if (tdvp != rtdvp)
1126 		vrele(tdvp);
1127 	if (ltvp != NULLVP)
1128 		VOP_UNLOCK(ltvp);
1129 	if (tvp != rtvp && tvp != NULLVP) {
1130 		if (rtvp == NULLVP)
1131 			vput(tvp);
1132 		else
1133 			vrele(tvp);
1134 	}
1135 
1136 	UNIONFS_INTERNAL_DEBUG("unionfs_rename: leave (%d)\n", error);
1137 
1138 	return (error);
1139 
1140 unionfs_rename_abort:
1141 	if (fdvp != rfdvp)
1142 		vrele(rfdvp);
1143 	if (fvp != rfvp)
1144 		vrele(rfvp);
1145 	if (tdvp != rtdvp)
1146 		vrele(rtdvp);
1147 	vput(tdvp);
1148 	if (tvp != rtvp && rtvp != NULLVP)
1149 		vrele(rtvp);
1150 	if (tvp != NULLVP) {
1151 		if (tdvp != tvp)
1152 			vput(tvp);
1153 		else
1154 			vrele(tvp);
1155 	}
1156 	vrele(fdvp);
1157 	vrele(fvp);
1158 
1159 	UNIONFS_INTERNAL_DEBUG("unionfs_rename: leave (%d)\n", error);
1160 
1161 	return (error);
1162 }
1163 
1164 static int
1165 unionfs_mkdir(void *v)
1166 {
1167 	struct vop_mkdir_args *ap = v;
1168 	int		error;
1169 	struct unionfs_node *dunp;
1170 	struct componentname *cnp;
1171 	struct vnode   *udvp;
1172 	struct vnode   *uvp;
1173 	struct vattr	va;
1174 
1175 	UNIONFS_INTERNAL_DEBUG("unionfs_mkdir: enter\n");
1176 
1177 	error = EROFS;
1178 	dunp = VTOUNIONFS(ap->a_dvp);
1179 	cnp = ap->a_cnp;
1180 	udvp = dunp->un_uppervp;
1181 
1182 	if (udvp != NULLVP) {
1183 		/* check opaque */
1184 		if (!(cnp->cn_flags & ISWHITEOUT)) {
1185 			error = VOP_GETATTR(udvp, &va, cnp->cn_cred);
1186 			if (error != 0)
1187 				return (error);
1188 			if (va.va_flags & OPAQUE)
1189 				cnp->cn_flags |= ISWHITEOUT;
1190 		}
1191 
1192 		if ((error = VOP_MKDIR(udvp, &uvp, cnp, ap->a_vap)) == 0) {
1193 			error = unionfs_nodeget(ap->a_dvp->v_mount, uvp, NULLVP,
1194 			    ap->a_dvp, ap->a_vpp, cnp);
1195 			if (error) {
1196 				vput(uvp);
1197 			} else {
1198 				vrele(uvp);
1199 			}
1200 		}
1201 	}
1202 
1203 	UNIONFS_INTERNAL_DEBUG("unionfs_mkdir: leave (%d)\n", error);
1204 
1205 	return (error);
1206 }
1207 
1208 static int
1209 unionfs_rmdir(void *v)
1210 {
1211 	struct vop_rmdir_v2_args *ap = v;
1212 	int		error;
1213 	struct unionfs_node *dunp;
1214 	struct unionfs_node *unp;
1215 	struct unionfs_mount *ump;
1216 	struct componentname *cnp;
1217 	struct vnode   *udvp;
1218 	struct vnode   *uvp;
1219 	struct vnode   *lvp;
1220 
1221 	UNIONFS_INTERNAL_DEBUG("unionfs_rmdir: enter\n");
1222 
1223 	error = 0;
1224 	dunp = VTOUNIONFS(ap->a_dvp);
1225 	unp = VTOUNIONFS(ap->a_vp);
1226 	cnp = ap->a_cnp;
1227 	udvp = dunp->un_uppervp;
1228 	uvp = unp->un_uppervp;
1229 	lvp = unp->un_lowervp;
1230 
1231 	if (udvp == NULLVP) {
1232 		vput(ap->a_vp);
1233 		return (EROFS);
1234 	}
1235 
1236 	if (udvp == uvp)
1237 		return (EOPNOTSUPP);
1238 
1239 	if (uvp != NULLVP) {
1240 		if (lvp != NULLVP) {
1241 			error = unionfs_check_rmdir(ap->a_vp, cnp->cn_cred);
1242 			if (error != 0)
1243 				return (error);
1244 		}
1245 		ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount);
1246 		if (ump->um_whitemode == UNIONFS_WHITE_ALWAYS || lvp != NULLVP)
1247 			cnp->cn_flags |= DOWHITEOUT;
1248 		error = VOP_RMDIR(udvp, uvp, cnp);
1249 	}
1250 	else if (lvp != NULLVP)
1251 		error = unionfs_mkwhiteout(udvp, cnp, unp->un_path);
1252 
1253 	if (error == 0) {
1254 		cache_purge(ap->a_dvp);
1255 		cache_purge(ap->a_vp);
1256 	}
1257 
1258 	UNIONFS_INTERNAL_DEBUG("unionfs_rmdir: leave (%d)\n", error);
1259 
1260 	return (error);
1261 }
1262 
1263 static int
1264 unionfs_symlink(void *v)
1265 {
1266 	struct vop_symlink_args *ap = v;
1267 	int		error;
1268 	struct unionfs_node *dunp;
1269 	struct componentname *cnp;
1270 	struct vnode   *udvp;
1271 	struct vnode   *uvp;
1272 
1273 	UNIONFS_INTERNAL_DEBUG("unionfs_symlink: enter\n");
1274 
1275 	error = EROFS;
1276 	dunp = VTOUNIONFS(ap->a_dvp);
1277 	cnp = ap->a_cnp;
1278 	udvp = dunp->un_uppervp;
1279 
1280 	if (udvp != NULLVP) {
1281 		error = VOP_SYMLINK(udvp, &uvp, cnp, ap->a_vap, ap->a_target);
1282 		if (error == 0) {
1283 			error = unionfs_nodeget(ap->a_dvp->v_mount, uvp, NULLVP,
1284 			    ap->a_dvp, ap->a_vpp, cnp);
1285 			if (error) {
1286 				vput(uvp);
1287 			} else {
1288 				vrele(uvp);
1289 			}
1290 		}
1291 	}
1292 
1293 	UNIONFS_INTERNAL_DEBUG("unionfs_symlink: leave (%d)\n", error);
1294 
1295 	return (error);
1296 }
1297 
1298 static int
1299 unionfs_readdir(void *v)
1300 {
1301 	struct vop_readdir_args *ap = v;
1302 	int		error;
1303 	int		eofflag;
1304 	int		locked;
1305 	struct unionfs_node *unp;
1306 	struct unionfs_node_status *unsp;
1307 	struct uio     *uio;
1308 	struct vnode   *uvp;
1309 	struct vnode   *lvp;
1310 	struct vattr    va;
1311 
1312 	int		ncookies_bk;
1313 	off_t          *cookies_bk;
1314 
1315 	UNIONFS_INTERNAL_DEBUG("unionfs_readdir: enter\n");
1316 
1317 	error = 0;
1318 	eofflag = 0;
1319 	locked = 0;
1320 	unp = VTOUNIONFS(ap->a_vp);
1321 	uio = ap->a_uio;
1322 	uvp = unp->un_uppervp;
1323 	lvp = unp->un_lowervp;
1324 	ncookies_bk = 0;
1325 	cookies_bk = NULL;
1326 
1327 	if (ap->a_vp->v_type != VDIR)
1328 		return (ENOTDIR);
1329 
1330 	/* check opaque */
1331 	if (uvp != NULLVP && lvp != NULLVP) {
1332 		if ((error = VOP_GETATTR(uvp, &va, ap->a_cred)) != 0)
1333 			goto unionfs_readdir_exit;
1334 		if (va.va_flags & OPAQUE)
1335 			lvp = NULLVP;
1336 	}
1337 
1338 	/* check the open count. unionfs needs to open before readdir. */
1339 	VOP_UNLOCK(ap->a_vp);
1340 	vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY);
1341 	unionfs_get_node_status(unp, &unsp);
1342 	if ((uvp != NULLVP && unsp->uns_upper_opencnt <= 0) ||
1343 	    (lvp != NULLVP && unsp->uns_lower_opencnt <= 0)) {
1344 		unionfs_tryrem_node_status(unp, unsp);
1345 		error = EBADF;
1346 	}
1347 	if (error != 0)
1348 		goto unionfs_readdir_exit;
1349 
1350 	/* upper only */
1351 	if (uvp != NULLVP && lvp == NULLVP) {
1352 		error = VOP_READDIR(uvp, uio, ap->a_cred, ap->a_eofflag,
1353 		    ap->a_cookies, ap->a_ncookies);
1354 		unsp->uns_readdir_status = 0;
1355 
1356 		goto unionfs_readdir_exit;
1357 	}
1358 
1359 	/* lower only */
1360 	if (uvp == NULLVP && lvp != NULLVP) {
1361 		error = VOP_READDIR(lvp, uio, ap->a_cred, ap->a_eofflag,
1362 		    ap->a_cookies, ap->a_ncookies);
1363 		unsp->uns_readdir_status = 2;
1364 
1365 		goto unionfs_readdir_exit;
1366 	}
1367 
1368 	/*
1369 	 * readdir upper and lower
1370 	 */
1371 	KASSERT(uvp != NULLVP);
1372 	KASSERT(lvp != NULLVP);
1373 	if (uio->uio_offset == 0)
1374 		unsp->uns_readdir_status = 0;
1375 
1376 	if (unsp->uns_readdir_status == 0) {
1377 		/* read upper */
1378 		error = VOP_READDIR(uvp, uio, ap->a_cred, &eofflag,
1379 				    ap->a_cookies, ap->a_ncookies);
1380 
1381 		if (error != 0 || eofflag == 0)
1382 			goto unionfs_readdir_exit;
1383 		unsp->uns_readdir_status = 1;
1384 
1385 		/*
1386 		 * ufs(and other fs) needs size of uio_resid larger than
1387 		 * DIRBLKSIZ.
1388 		 * size of DIRBLKSIZ equals DEV_BSIZE.
1389 		 * (see: ufs/ufs/ufs_vnops.c ufs_readdir func , ufs/ufs/dir.h)
1390 		 */
1391 		if (uio->uio_resid <= (uio->uio_resid & (DEV_BSIZE -1)))
1392 			goto unionfs_readdir_exit;
1393 
1394 		/*
1395 		 * backup cookies
1396 		 * It prepares to readdir in lower.
1397 		 */
1398 		if (ap->a_ncookies != NULL) {
1399 			ncookies_bk = *(ap->a_ncookies);
1400 			*(ap->a_ncookies) = 0;
1401 		}
1402 		if (ap->a_cookies != NULL) {
1403 			cookies_bk = *(ap->a_cookies);
1404 			*(ap->a_cookies) = NULL;
1405 		}
1406 	}
1407 
1408 	/* initialize for readdir in lower */
1409 	if (unsp->uns_readdir_status == 1) {
1410 		unsp->uns_readdir_status = 2;
1411 		uio->uio_offset = 0;
1412 	}
1413 
1414 	if (lvp == NULLVP) {
1415 		error = EBADF;
1416 		goto unionfs_readdir_exit;
1417 	}
1418 	/* read lower */
1419 	error = VOP_READDIR(lvp, uio, ap->a_cred, ap->a_eofflag,
1420 			    ap->a_cookies, ap->a_ncookies);
1421 
1422 	if (cookies_bk != NULL) {
1423 		/* merge cookies */
1424 		int		size;
1425 		off_t         *newcookies, *pos;
1426 
1427 		size = *(ap->a_ncookies) + ncookies_bk;
1428 		newcookies = (off_t *) malloc(size * sizeof(off_t),
1429 		    M_TEMP, M_WAITOK);
1430 		pos = newcookies;
1431 
1432 		memcpy(pos, cookies_bk, ncookies_bk * sizeof(off_t));
1433 		pos += ncookies_bk * sizeof(off_t);
1434 		memcpy(pos, *(ap->a_cookies), *(ap->a_ncookies) * sizeof(off_t));
1435 		free(cookies_bk, M_TEMP);
1436 		free(*(ap->a_cookies), M_TEMP);
1437 		*(ap->a_ncookies) = size;
1438 		*(ap->a_cookies) = newcookies;
1439 	}
1440 
1441 unionfs_readdir_exit:
1442 	if (error != 0 && ap->a_eofflag != NULL)
1443 		*(ap->a_eofflag) = 1;
1444 
1445 	UNIONFS_INTERNAL_DEBUG("unionfs_readdir: leave (%d)\n", error);
1446 
1447 	return (error);
1448 }
1449 
1450 static int
1451 unionfs_readlink(void *v)
1452 {
1453 	struct vop_readlink_args *ap = v;
1454 	int error;
1455 	struct unionfs_node *unp;
1456 	struct vnode   *vp;
1457 
1458 	UNIONFS_INTERNAL_DEBUG("unionfs_readlink: enter\n");
1459 
1460 	unp = VTOUNIONFS(ap->a_vp);
1461 	vp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1462 
1463 	error = VOP_READLINK(vp, ap->a_uio, ap->a_cred);
1464 
1465 	UNIONFS_INTERNAL_DEBUG("unionfs_readlink: leave (%d)\n", error);
1466 
1467 	return (error);
1468 }
1469 
1470 static int
1471 unionfs_inactive(void *v)
1472 {
1473 	struct vop_inactive_v2_args *ap = v;
1474 	*ap->a_recycle = true;
1475 	return (0);
1476 }
1477 
1478 static int
1479 unionfs_reclaim(void *v)
1480 {
1481 	struct vop_reclaim_v2_args *ap = v;
1482 
1483 	/* UNIONFS_INTERNAL_DEBUG("unionfs_reclaim: enter\n"); */
1484 
1485 	VOP_UNLOCK(ap->a_vp);
1486 
1487 	unionfs_noderem(ap->a_vp);
1488 
1489 	/* UNIONFS_INTERNAL_DEBUG("unionfs_reclaim: leave\n"); */
1490 
1491 	return (0);
1492 }
1493 
1494 static int
1495 unionfs_print(void *v)
1496 {
1497 	struct vop_print_args *ap = v;
1498 	struct unionfs_node *unp;
1499 	/* struct unionfs_node_status *unsp; */
1500 
1501 	unp = VTOUNIONFS(ap->a_vp);
1502 	/* unionfs_get_node_status(unp, &unsp); */
1503 
1504 	printf("unionfs_vp=%p, uppervp=%p, lowervp=%p\n",
1505 	    ap->a_vp, unp->un_uppervp, unp->un_lowervp);
1506 	/*
1507 	printf("unionfs opencnt: uppervp=%d, lowervp=%d\n",
1508 	    unsp->uns_upper_opencnt, unsp->uns_lower_opencnt);
1509 	*/
1510 
1511 	if (unp->un_uppervp != NULLVP)
1512 		vprint("unionfs: upper", unp->un_uppervp);
1513 	if (unp->un_lowervp != NULLVP)
1514 		vprint("unionfs: lower", unp->un_lowervp);
1515 
1516 	return (0);
1517 }
1518 
1519 static int
1520 unionfs_lock(void *v)
1521 {
1522 	struct vop_lock_args *ap = v;
1523 	int		error;
1524 	int		flags;
1525 	struct vnode   *lvp;
1526 	struct vnode   *uvp;
1527 	struct unionfs_node *unp;
1528 
1529 	unp = VTOUNIONFS(ap->a_vp);
1530 	lvp = unp->un_lowervp;
1531 	uvp = unp->un_uppervp;
1532 	flags = ap->a_flags;
1533 	error = 0;
1534 
1535 	if (lvp != NULLVP) {
1536 		error = VOP_LOCK(lvp, flags);
1537 	}
1538 	if (error == 0 && uvp != NULLVP) {
1539 		error = VOP_LOCK(uvp, flags);
1540 		if (error != 0) {
1541 			VOP_UNLOCK(lvp);
1542 		}
1543 	}
1544 
1545 	return error;
1546 }
1547 
1548 static int
1549 unionfs_unlock(void *v)
1550 {
1551 	struct vop_unlock_args *ap = v;
1552 	int		error;
1553 	struct vnode   *lvp;
1554 	struct vnode   *uvp;
1555 	struct unionfs_node *unp;
1556 
1557 	unp = VTOUNIONFS(ap->a_vp);
1558 	lvp = unp->un_lowervp;
1559 	uvp = unp->un_uppervp;
1560 	error = 0;
1561 
1562 	if (lvp != NULLVP) {
1563 		error = VOP_UNLOCK(lvp);
1564 	}
1565 	if (error == 0 && uvp != NULLVP) {
1566 		error = VOP_UNLOCK(uvp);
1567 	}
1568 
1569 	return error;
1570 }
1571 
1572 static int
1573 unionfs_pathconf(void *v)
1574 {
1575 	struct vop_pathconf_args *ap = v;
1576 	struct unionfs_node *unp;
1577 	struct vnode   *vp;
1578 
1579 	unp = VTOUNIONFS(ap->a_vp);
1580 	vp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1581 
1582 	return (VOP_PATHCONF(vp, ap->a_name, ap->a_retval));
1583 }
1584 
1585 static int
1586 unionfs_advlock(void *v)
1587 {
1588 	struct vop_advlock_args *ap = v;
1589 	int error;
1590 	struct unionfs_node *unp;
1591 	struct unionfs_node_status *unsp;
1592 	struct vnode   *vp;
1593 	struct vnode   *uvp;
1594 	kauth_cred_t	cred;
1595 
1596 	UNIONFS_INTERNAL_DEBUG("unionfs_advlock: enter\n");
1597 
1598 	vp = ap->a_vp;
1599 	cred = kauth_cred_get();
1600 
1601 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1602 
1603 	unp = VTOUNIONFS(ap->a_vp);
1604 	uvp = unp->un_uppervp;
1605 
1606 	if (uvp == NULLVP) {
1607 		error = unionfs_copyfile(unp, 1, cred);
1608 		if (error != 0)
1609 			goto unionfs_advlock_abort;
1610 		uvp = unp->un_uppervp;
1611 
1612 		unionfs_get_node_status(unp, &unsp);
1613 		if (unsp->uns_lower_opencnt > 0) {
1614 			/* try reopen the vnode */
1615 			error = VOP_OPEN(uvp, unsp->uns_lower_openmode, cred);
1616 			if (error)
1617 				goto unionfs_advlock_abort;
1618 			unsp->uns_upper_opencnt++;
1619 			VOP_CLOSE(unp->un_lowervp, unsp->uns_lower_openmode, cred);
1620 			unsp->uns_lower_opencnt--;
1621 		} else
1622 			unionfs_tryrem_node_status(unp, unsp);
1623 	}
1624 
1625 	VOP_UNLOCK(vp);
1626 
1627 	error = VOP_ADVLOCK(uvp, ap->a_id, ap->a_op, ap->a_fl, ap->a_flags);
1628 
1629 	UNIONFS_INTERNAL_DEBUG("unionfs_advlock: leave (%d)\n", error);
1630 
1631 	return error;
1632 
1633 unionfs_advlock_abort:
1634 	VOP_UNLOCK(vp);
1635 
1636 	UNIONFS_INTERNAL_DEBUG("unionfs_advlock: leave (%d)\n", error);
1637 
1638 	return error;
1639 }
1640 
1641 static int
1642 unionfs_strategy(void *v)
1643 {
1644 	struct vop_strategy_args *ap = v;
1645 	struct unionfs_node *unp;
1646 	struct vnode   *vp;
1647 
1648 	unp = VTOUNIONFS(ap->a_vp);
1649 	vp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1650 
1651 #ifdef DIAGNOSTIC
1652 	if (vp == NULLVP)
1653 		panic("unionfs_strategy: nullvp");
1654 	if ((ap->a_bp->b_flags & B_READ) == 0 && vp == unp->un_lowervp)
1655 		panic("unionfs_strategy: writing to lowervp");
1656 #endif
1657 
1658 	return (VOP_STRATEGY(vp, ap->a_bp));
1659 }
1660 
1661 static int
1662 unionfs_kqfilter(void *v)
1663 {
1664 	struct vop_kqfilter_args *ap = v;
1665 	struct unionfs_node *unp;
1666 	struct vnode   *tvp;
1667 
1668 	unp = VTOUNIONFS(ap->a_vp);
1669 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1670 
1671 	return VOP_KQFILTER(tvp, ap->a_kn);
1672 }
1673 
1674 static int
1675 unionfs_bmap(void *v)
1676 {
1677 	struct vop_bmap_args *ap = v;
1678 	struct unionfs_node *unp;
1679 	struct vnode   *tvp;
1680 
1681 	unp = VTOUNIONFS(ap->a_vp);
1682 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1683 
1684 	return VOP_BMAP(tvp, ap->a_bn, ap->a_vpp, ap->a_bnp, ap->a_runp);
1685 }
1686 
1687 static int
1688 unionfs_mmap(void *v)
1689 {
1690 	struct vop_mmap_args *ap = v;
1691 	struct unionfs_node *unp;
1692 	struct vnode   *tvp;
1693 
1694 	unp = VTOUNIONFS(ap->a_vp);
1695 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1696 
1697 	return VOP_MMAP(tvp, ap->a_prot, ap->a_cred);
1698 }
1699 
1700 static int
1701 unionfs_abortop(void *v)
1702 {
1703 	struct vop_abortop_args *ap = v;
1704 	struct unionfs_node *unp;
1705 	struct vnode   *tvp;
1706 
1707 	unp = VTOUNIONFS(ap->a_dvp);
1708 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1709 
1710 	return VOP_ABORTOP(tvp, ap->a_cnp);
1711 }
1712 
1713 static int
1714 unionfs_islocked(void *v)
1715 {
1716 	struct vop_islocked_args *ap = v;
1717 	struct unionfs_node *unp;
1718 	struct vnode   *tvp;
1719 
1720 	unp = VTOUNIONFS(ap->a_vp);
1721 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1722 
1723 	return VOP_ISLOCKED(tvp);
1724 }
1725 
1726 static int
1727 unionfs_seek(void *v)
1728 {
1729 	struct vop_seek_args *ap = v;
1730 	struct unionfs_node *unp;
1731 	struct vnode   *tvp;
1732 
1733 	unp = VTOUNIONFS(ap->a_vp);
1734 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1735 
1736 	return VOP_SEEK(tvp, ap->a_oldoff, ap->a_newoff, ap->a_cred);
1737 }
1738 
1739 static int
1740 unionfs_putpages(void *v)
1741 {
1742 	struct vop_putpages_args /* {
1743 		struct vnode *a_vp;
1744 		voff_t a_offlo;
1745 		voff_t a_offhi;
1746 		int a_flags;
1747 	} */ *ap = v;
1748 	struct vnode *vp = ap->a_vp, *tvp;
1749 	struct unionfs_node *unp;
1750 
1751 	KASSERT(rw_lock_held(vp->v_uobj.vmobjlock));
1752 
1753 	unp = VTOUNIONFS(vp);
1754 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1755 	KASSERT(tvp->v_uobj.vmobjlock == vp->v_uobj.vmobjlock);
1756 
1757 	if (ap->a_flags & PGO_RECLAIM) {
1758 		rw_exit(vp->v_uobj.vmobjlock);
1759 		return 0;
1760 	}
1761 	return VOP_PUTPAGES(tvp, ap->a_offlo, ap->a_offhi, ap->a_flags);
1762 }
1763 
1764 static int
1765 unionfs_getpages(void *v)
1766 {
1767 	struct vop_getpages_args /* {
1768 		struct vnode *a_vp;
1769 		voff_t a_offset;
1770 		struct vm_page **a_m;
1771 		int *a_count;
1772 		int a_centeridx;
1773 		vm_prot_t a_access_type;
1774 		int a_advice;
1775 		int a_flags;
1776 	} */ *ap = v;
1777 	struct vnode *vp = ap->a_vp, *tvp;
1778 	struct unionfs_node *unp;
1779 
1780 	KASSERT(rw_lock_held(vp->v_uobj.vmobjlock));
1781 
1782 	unp = VTOUNIONFS(vp);
1783 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1784 	KASSERT(tvp->v_uobj.vmobjlock == vp->v_uobj.vmobjlock);
1785 
1786 	if (ap->a_flags & PGO_LOCKED) {
1787 		return EBUSY;
1788 	}
1789 	return VOP_GETPAGES(tvp, ap->a_offset, ap->a_m, ap->a_count,
1790 	    ap->a_centeridx, ap->a_access_type, ap->a_advice, ap->a_flags);
1791 }
1792 
1793 static int
1794 unionfs_revoke(void *v)
1795 {
1796 	struct vop_revoke_args *ap = v;
1797 	struct unionfs_node *unp;
1798 	struct vnode   *tvp;
1799 	int error;
1800 
1801 	unp = VTOUNIONFS(ap->a_vp);
1802 	tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp);
1803 
1804 	error = VOP_REVOKE(tvp, ap->a_flags);
1805 	if (error == 0) {
1806 		vgone(ap->a_vp);	/* ??? */
1807 	}
1808 	return error;
1809 }
1810 
1811 /*
1812  * Global vfs data structures
1813  */
1814 int (**unionfs_vnodeop_p)(void *);
1815 const struct vnodeopv_entry_desc unionfs_vnodeop_entries[] = {
1816 	{ &vop_default_desc, vn_default_error },
1817 	{ &vop_lookup_desc, unionfs_lookup },		/* lookup */
1818 	{ &vop_create_desc, unionfs_create },		/* create */
1819 	{ &vop_whiteout_desc, unionfs_whiteout },	/* whiteout */
1820 	{ &vop_mknod_desc, unionfs_mknod },		/* mknod */
1821 	{ &vop_open_desc, unionfs_open },		/* open */
1822 	{ &vop_close_desc, unionfs_close },		/* close */
1823 	{ &vop_access_desc, unionfs_access },		/* access */
1824 	{ &vop_accessx_desc, genfs_accessx },		/* accessx */
1825 	{ &vop_getattr_desc, unionfs_getattr },		/* getattr */
1826 	{ &vop_setattr_desc, unionfs_setattr },		/* setattr */
1827 	{ &vop_read_desc, unionfs_read },		/* read */
1828 	{ &vop_write_desc, unionfs_write },		/* write */
1829 	{ &vop_fallocate_desc, genfs_eopnotsupp },	/* fallocate */
1830 	{ &vop_fdiscard_desc, genfs_eopnotsupp },	/* fdiscard */
1831 	{ &vop_ioctl_desc, unionfs_ioctl },		/* ioctl */
1832 	{ &vop_poll_desc, unionfs_poll },		/* select */
1833 	{ &vop_revoke_desc, unionfs_revoke },		/* revoke */
1834 	{ &vop_mmap_desc, unionfs_mmap },		/* mmap */
1835 	{ &vop_fsync_desc, unionfs_fsync },		/* fsync */
1836 	{ &vop_seek_desc, unionfs_seek },		/* seek */
1837 	{ &vop_remove_desc, unionfs_remove },		/* remove */
1838 	{ &vop_link_desc, unionfs_link },		/* link */
1839 	{ &vop_rename_desc, unionfs_rename },		/* rename */
1840 	{ &vop_mkdir_desc, unionfs_mkdir },		/* mkdir */
1841 	{ &vop_rmdir_desc, unionfs_rmdir },		/* rmdir */
1842 	{ &vop_symlink_desc, unionfs_symlink },		/* symlink */
1843 	{ &vop_readdir_desc, unionfs_readdir },		/* readdir */
1844 	{ &vop_readlink_desc, unionfs_readlink },	/* readlink */
1845 	{ &vop_abortop_desc, unionfs_abortop },		/* abortop */
1846 	{ &vop_inactive_desc, unionfs_inactive },	/* inactive */
1847 	{ &vop_reclaim_desc, unionfs_reclaim },		/* reclaim */
1848 	{ &vop_lock_desc, unionfs_lock },		/* lock */
1849 	{ &vop_unlock_desc, unionfs_unlock },		/* unlock */
1850 	{ &vop_bmap_desc, unionfs_bmap },		/* bmap */
1851 	{ &vop_strategy_desc, unionfs_strategy },	/* strategy */
1852 	{ &vop_print_desc, unionfs_print },		/* print */
1853 	{ &vop_islocked_desc, unionfs_islocked },	/* islocked */
1854 	{ &vop_pathconf_desc, unionfs_pathconf },	/* pathconf */
1855 	{ &vop_advlock_desc, unionfs_advlock },		/* advlock */
1856 	{ &vop_getpages_desc, unionfs_getpages },	/* getpages */
1857 	{ &vop_putpages_desc, unionfs_putpages },	/* putpages */
1858 	{ &vop_kqfilter_desc, unionfs_kqfilter },	/* kqfilter */
1859 #ifdef notdef
1860 	{ &vop_bwrite_desc, unionfs_bwrite },		/* bwrite */
1861 #endif
1862 	{ NULL, NULL }
1863 };
1864 const struct vnodeopv_desc unionfs_vnodeop_opv_desc =
1865 	{ &unionfs_vnodeop_p, unionfs_vnodeop_entries };
1866