xref: /freebsd/sys/fs/tmpfs/tmpfs_vnops.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /*	$NetBSD: tmpfs_vnops.c,v 1.39 2007/07/23 15:41:01 jmmv Exp $	*/
2 
3 /*-
4  * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Julio M. Merino Vidal, developed as part of Google's Summer of Code
9  * 2005 program.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * tmpfs vnode interface.
35  */
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 
39 #include <sys/param.h>
40 #include <sys/fcntl.h>
41 #include <sys/lockf.h>
42 #include <sys/lock.h>
43 #include <sys/namei.h>
44 #include <sys/priv.h>
45 #include <sys/proc.h>
46 #include <sys/rwlock.h>
47 #include <sys/sched.h>
48 #include <sys/stat.h>
49 #include <sys/systm.h>
50 #include <sys/sysctl.h>
51 #include <sys/unistd.h>
52 #include <sys/vnode.h>
53 
54 #include <vm/vm.h>
55 #include <vm/vm_param.h>
56 #include <vm/vm_object.h>
57 #include <vm/vm_page.h>
58 #include <vm/vm_pager.h>
59 
60 #include <fs/tmpfs/tmpfs_vnops.h>
61 #include <fs/tmpfs/tmpfs.h>
62 
63 SYSCTL_DECL(_vfs_tmpfs);
64 
65 static volatile int tmpfs_rename_restarts;
66 SYSCTL_INT(_vfs_tmpfs, OID_AUTO, rename_restarts, CTLFLAG_RD,
67     __DEVOLATILE(int *, &tmpfs_rename_restarts), 0,
68     "Times rename had to restart due to lock contention");
69 
70 static int
71 tmpfs_vn_get_ino_alloc(struct mount *mp, void *arg, int lkflags,
72     struct vnode **rvp)
73 {
74 
75 	return (tmpfs_alloc_vp(mp, arg, lkflags, rvp));
76 }
77 
78 static int
79 tmpfs_lookup(struct vop_cachedlookup_args *v)
80 {
81 	struct vnode *dvp = v->a_dvp;
82 	struct vnode **vpp = v->a_vpp;
83 	struct componentname *cnp = v->a_cnp;
84 	struct tmpfs_dirent *de;
85 	struct tmpfs_node *dnode;
86 	int error;
87 
88 	dnode = VP_TO_TMPFS_DIR(dvp);
89 	*vpp = NULLVP;
90 
91 	/* Check accessibility of requested node as a first step. */
92 	error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, cnp->cn_thread);
93 	if (error != 0)
94 		goto out;
95 
96 	/* We cannot be requesting the parent directory of the root node. */
97 	MPASS(IMPLIES(dnode->tn_type == VDIR &&
98 	    dnode->tn_dir.tn_parent == dnode,
99 	    !(cnp->cn_flags & ISDOTDOT)));
100 
101 	TMPFS_ASSERT_LOCKED(dnode);
102 	if (dnode->tn_dir.tn_parent == NULL) {
103 		error = ENOENT;
104 		goto out;
105 	}
106 	if (cnp->cn_flags & ISDOTDOT) {
107 		error = vn_vget_ino_gen(dvp, tmpfs_vn_get_ino_alloc,
108 		    dnode->tn_dir.tn_parent, cnp->cn_lkflags, vpp);
109 		if (error != 0)
110 			goto out;
111 	} else if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
112 		VREF(dvp);
113 		*vpp = dvp;
114 		error = 0;
115 	} else {
116 		de = tmpfs_dir_lookup(dnode, NULL, cnp);
117 		if (de != NULL && de->td_node == NULL)
118 			cnp->cn_flags |= ISWHITEOUT;
119 		if (de == NULL || de->td_node == NULL) {
120 			/* The entry was not found in the directory.
121 			 * This is OK if we are creating or renaming an
122 			 * entry and are working on the last component of
123 			 * the path name. */
124 			if ((cnp->cn_flags & ISLASTCN) &&
125 			    (cnp->cn_nameiop == CREATE || \
126 			    cnp->cn_nameiop == RENAME ||
127 			    (cnp->cn_nameiop == DELETE &&
128 			    cnp->cn_flags & DOWHITEOUT &&
129 			    cnp->cn_flags & ISWHITEOUT))) {
130 				error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred,
131 				    cnp->cn_thread);
132 				if (error != 0)
133 					goto out;
134 
135 				/* Keep the component name in the buffer for
136 				 * future uses. */
137 				cnp->cn_flags |= SAVENAME;
138 
139 				error = EJUSTRETURN;
140 			} else
141 				error = ENOENT;
142 		} else {
143 			struct tmpfs_node *tnode;
144 
145 			/* The entry was found, so get its associated
146 			 * tmpfs_node. */
147 			tnode = de->td_node;
148 
149 			/* If we are not at the last path component and
150 			 * found a non-directory or non-link entry (which
151 			 * may itself be pointing to a directory), raise
152 			 * an error. */
153 			if ((tnode->tn_type != VDIR &&
154 			    tnode->tn_type != VLNK) &&
155 			    !(cnp->cn_flags & ISLASTCN)) {
156 				error = ENOTDIR;
157 				goto out;
158 			}
159 
160 			/* If we are deleting or renaming the entry, keep
161 			 * track of its tmpfs_dirent so that it can be
162 			 * easily deleted later. */
163 			if ((cnp->cn_flags & ISLASTCN) &&
164 			    (cnp->cn_nameiop == DELETE ||
165 			    cnp->cn_nameiop == RENAME)) {
166 				error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred,
167 				    cnp->cn_thread);
168 				if (error != 0)
169 					goto out;
170 
171 				/* Allocate a new vnode on the matching entry. */
172 				error = tmpfs_alloc_vp(dvp->v_mount, tnode,
173 				    cnp->cn_lkflags, vpp);
174 				if (error != 0)
175 					goto out;
176 
177 				if ((dnode->tn_mode & S_ISTXT) &&
178 				  VOP_ACCESS(dvp, VADMIN, cnp->cn_cred, cnp->cn_thread) &&
179 				  VOP_ACCESS(*vpp, VADMIN, cnp->cn_cred, cnp->cn_thread)) {
180 					error = EPERM;
181 					vput(*vpp);
182 					*vpp = NULL;
183 					goto out;
184 				}
185 				cnp->cn_flags |= SAVENAME;
186 			} else {
187 				error = tmpfs_alloc_vp(dvp->v_mount, tnode,
188 				    cnp->cn_lkflags, vpp);
189 				if (error != 0)
190 					goto out;
191 			}
192 		}
193 	}
194 
195 	/* Store the result of this lookup in the cache.  Avoid this if the
196 	 * request was for creation, as it does not improve timings on
197 	 * emprical tests. */
198 	if ((cnp->cn_flags & MAKEENTRY) && cnp->cn_nameiop != CREATE)
199 		cache_enter(dvp, *vpp, cnp);
200 
201 out:
202 	/* If there were no errors, *vpp cannot be null and it must be
203 	 * locked. */
204 	MPASS(IFF(error == 0, *vpp != NULLVP && VOP_ISLOCKED(*vpp)));
205 
206 	return error;
207 }
208 
209 static int
210 tmpfs_create(struct vop_create_args *v)
211 {
212 	struct vnode *dvp = v->a_dvp;
213 	struct vnode **vpp = v->a_vpp;
214 	struct componentname *cnp = v->a_cnp;
215 	struct vattr *vap = v->a_vap;
216 
217 	MPASS(vap->va_type == VREG || vap->va_type == VSOCK);
218 
219 	return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
220 }
221 
222 static int
223 tmpfs_mknod(struct vop_mknod_args *v)
224 {
225 	struct vnode *dvp = v->a_dvp;
226 	struct vnode **vpp = v->a_vpp;
227 	struct componentname *cnp = v->a_cnp;
228 	struct vattr *vap = v->a_vap;
229 
230 	if (vap->va_type != VBLK && vap->va_type != VCHR &&
231 	    vap->va_type != VFIFO)
232 		return EINVAL;
233 
234 	return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
235 }
236 
237 static int
238 tmpfs_open(struct vop_open_args *v)
239 {
240 	struct vnode *vp = v->a_vp;
241 	int mode = v->a_mode;
242 
243 	int error;
244 	struct tmpfs_node *node;
245 
246 	MPASS(VOP_ISLOCKED(vp));
247 
248 	node = VP_TO_TMPFS_NODE(vp);
249 
250 	/* The file is still active but all its names have been removed
251 	 * (e.g. by a "rmdir $(pwd)").  It cannot be opened any more as
252 	 * it is about to die. */
253 	if (node->tn_links < 1)
254 		return (ENOENT);
255 
256 	/* If the file is marked append-only, deny write requests. */
257 	if (node->tn_flags & APPEND && (mode & (FWRITE | O_APPEND)) == FWRITE)
258 		error = EPERM;
259 	else {
260 		error = 0;
261 		/* For regular files, the call below is nop. */
262 		KASSERT(vp->v_type != VREG || (node->tn_reg.tn_aobj->flags &
263 		    OBJ_DEAD) == 0, ("dead object"));
264 		vnode_create_vobject(vp, node->tn_size, v->a_td);
265 	}
266 
267 	MPASS(VOP_ISLOCKED(vp));
268 	return error;
269 }
270 
271 static int
272 tmpfs_close(struct vop_close_args *v)
273 {
274 	struct vnode *vp = v->a_vp;
275 
276 	/* Update node times. */
277 	tmpfs_update(vp);
278 
279 	return (0);
280 }
281 
282 int
283 tmpfs_access(struct vop_access_args *v)
284 {
285 	struct vnode *vp = v->a_vp;
286 	accmode_t accmode = v->a_accmode;
287 	struct ucred *cred = v->a_cred;
288 
289 	int error;
290 	struct tmpfs_node *node;
291 
292 	MPASS(VOP_ISLOCKED(vp));
293 
294 	node = VP_TO_TMPFS_NODE(vp);
295 
296 	switch (vp->v_type) {
297 	case VDIR:
298 		/* FALLTHROUGH */
299 	case VLNK:
300 		/* FALLTHROUGH */
301 	case VREG:
302 		if (accmode & VWRITE && vp->v_mount->mnt_flag & MNT_RDONLY) {
303 			error = EROFS;
304 			goto out;
305 		}
306 		break;
307 
308 	case VBLK:
309 		/* FALLTHROUGH */
310 	case VCHR:
311 		/* FALLTHROUGH */
312 	case VSOCK:
313 		/* FALLTHROUGH */
314 	case VFIFO:
315 		break;
316 
317 	default:
318 		error = EINVAL;
319 		goto out;
320 	}
321 
322 	if (accmode & VWRITE && node->tn_flags & IMMUTABLE) {
323 		error = EPERM;
324 		goto out;
325 	}
326 
327 	error = vaccess(vp->v_type, node->tn_mode, node->tn_uid,
328 	    node->tn_gid, accmode, cred, NULL);
329 
330 out:
331 	MPASS(VOP_ISLOCKED(vp));
332 
333 	return error;
334 }
335 
336 int
337 tmpfs_getattr(struct vop_getattr_args *v)
338 {
339 	struct vnode *vp = v->a_vp;
340 	struct vattr *vap = v->a_vap;
341 
342 	struct tmpfs_node *node;
343 
344 	node = VP_TO_TMPFS_NODE(vp);
345 
346 	tmpfs_update(vp);
347 
348 	vap->va_type = vp->v_type;
349 	vap->va_mode = node->tn_mode;
350 	vap->va_nlink = node->tn_links;
351 	vap->va_uid = node->tn_uid;
352 	vap->va_gid = node->tn_gid;
353 	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
354 	vap->va_fileid = node->tn_id;
355 	vap->va_size = node->tn_size;
356 	vap->va_blocksize = PAGE_SIZE;
357 	vap->va_atime = node->tn_atime;
358 	vap->va_mtime = node->tn_mtime;
359 	vap->va_ctime = node->tn_ctime;
360 	vap->va_birthtime = node->tn_birthtime;
361 	vap->va_gen = node->tn_gen;
362 	vap->va_flags = node->tn_flags;
363 	vap->va_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ?
364 		node->tn_rdev : NODEV;
365 	vap->va_bytes = round_page(node->tn_size);
366 	vap->va_filerev = 0;
367 
368 	return 0;
369 }
370 
371 int
372 tmpfs_setattr(struct vop_setattr_args *v)
373 {
374 	struct vnode *vp = v->a_vp;
375 	struct vattr *vap = v->a_vap;
376 	struct ucred *cred = v->a_cred;
377 	struct thread *td = curthread;
378 
379 	int error;
380 
381 	MPASS(VOP_ISLOCKED(vp));
382 
383 	error = 0;
384 
385 	/* Abort if any unsettable attribute is given. */
386 	if (vap->va_type != VNON ||
387 	    vap->va_nlink != VNOVAL ||
388 	    vap->va_fsid != VNOVAL ||
389 	    vap->va_fileid != VNOVAL ||
390 	    vap->va_blocksize != VNOVAL ||
391 	    vap->va_gen != VNOVAL ||
392 	    vap->va_rdev != VNOVAL ||
393 	    vap->va_bytes != VNOVAL)
394 		error = EINVAL;
395 
396 	if (error == 0 && (vap->va_flags != VNOVAL))
397 		error = tmpfs_chflags(vp, vap->va_flags, cred, td);
398 
399 	if (error == 0 && (vap->va_size != VNOVAL))
400 		error = tmpfs_chsize(vp, vap->va_size, cred, td);
401 
402 	if (error == 0 && (vap->va_uid != VNOVAL || vap->va_gid != VNOVAL))
403 		error = tmpfs_chown(vp, vap->va_uid, vap->va_gid, cred, td);
404 
405 	if (error == 0 && (vap->va_mode != (mode_t)VNOVAL))
406 		error = tmpfs_chmod(vp, vap->va_mode, cred, td);
407 
408 	if (error == 0 && ((vap->va_atime.tv_sec != VNOVAL &&
409 	    vap->va_atime.tv_nsec != VNOVAL) ||
410 	    (vap->va_mtime.tv_sec != VNOVAL &&
411 	    vap->va_mtime.tv_nsec != VNOVAL) ||
412 	    (vap->va_birthtime.tv_sec != VNOVAL &&
413 	    vap->va_birthtime.tv_nsec != VNOVAL)))
414 		error = tmpfs_chtimes(vp, vap, cred, td);
415 
416 	/* Update the node times.  We give preference to the error codes
417 	 * generated by this function rather than the ones that may arise
418 	 * from tmpfs_update. */
419 	tmpfs_update(vp);
420 
421 	MPASS(VOP_ISLOCKED(vp));
422 
423 	return error;
424 }
425 
426 static int
427 tmpfs_read(struct vop_read_args *v)
428 {
429 	struct vnode *vp;
430 	struct uio *uio;
431 	struct tmpfs_node *node;
432 
433 	vp = v->a_vp;
434 	if (vp->v_type != VREG)
435 		return (EISDIR);
436 	uio = v->a_uio;
437 	if (uio->uio_offset < 0)
438 		return (EINVAL);
439 	node = VP_TO_TMPFS_NODE(vp);
440 	node->tn_status |= TMPFS_NODE_ACCESSED;
441 	return (uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio));
442 }
443 
444 static int
445 tmpfs_write(struct vop_write_args *v)
446 {
447 	struct vnode *vp;
448 	struct uio *uio;
449 	struct tmpfs_node *node;
450 	off_t oldsize;
451 	int error, ioflag;
452 	boolean_t extended;
453 
454 	vp = v->a_vp;
455 	uio = v->a_uio;
456 	ioflag = v->a_ioflag;
457 	error = 0;
458 	node = VP_TO_TMPFS_NODE(vp);
459 	oldsize = node->tn_size;
460 
461 	if (uio->uio_offset < 0 || vp->v_type != VREG)
462 		return (EINVAL);
463 	if (uio->uio_resid == 0)
464 		return (0);
465 	if (ioflag & IO_APPEND)
466 		uio->uio_offset = node->tn_size;
467 	if (uio->uio_offset + uio->uio_resid >
468 	  VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize)
469 		return (EFBIG);
470 	if (vn_rlimit_fsize(vp, uio, uio->uio_td))
471 		return (EFBIG);
472 	extended = uio->uio_offset + uio->uio_resid > node->tn_size;
473 	if (extended) {
474 		error = tmpfs_reg_resize(vp, uio->uio_offset + uio->uio_resid,
475 		    FALSE);
476 		if (error != 0)
477 			goto out;
478 	}
479 
480 	error = uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio);
481 	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED |
482 	    (extended ? TMPFS_NODE_CHANGED : 0);
483 	if (node->tn_mode & (S_ISUID | S_ISGID)) {
484 		if (priv_check_cred(v->a_cred, PRIV_VFS_RETAINSUGID, 0))
485 			node->tn_mode &= ~(S_ISUID | S_ISGID);
486 	}
487 	if (error != 0)
488 		(void)tmpfs_reg_resize(vp, oldsize, TRUE);
489 
490 out:
491 	MPASS(IMPLIES(error == 0, uio->uio_resid == 0));
492 	MPASS(IMPLIES(error != 0, oldsize == node->tn_size));
493 
494 	return (error);
495 }
496 
497 static int
498 tmpfs_fsync(struct vop_fsync_args *v)
499 {
500 	struct vnode *vp = v->a_vp;
501 
502 	MPASS(VOP_ISLOCKED(vp));
503 
504 	tmpfs_update(vp);
505 
506 	return 0;
507 }
508 
509 static int
510 tmpfs_remove(struct vop_remove_args *v)
511 {
512 	struct vnode *dvp = v->a_dvp;
513 	struct vnode *vp = v->a_vp;
514 
515 	int error;
516 	struct tmpfs_dirent *de;
517 	struct tmpfs_mount *tmp;
518 	struct tmpfs_node *dnode;
519 	struct tmpfs_node *node;
520 
521 	MPASS(VOP_ISLOCKED(dvp));
522 	MPASS(VOP_ISLOCKED(vp));
523 
524 	if (vp->v_type == VDIR) {
525 		error = EISDIR;
526 		goto out;
527 	}
528 
529 	dnode = VP_TO_TMPFS_DIR(dvp);
530 	node = VP_TO_TMPFS_NODE(vp);
531 	tmp = VFS_TO_TMPFS(vp->v_mount);
532 	de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
533 	MPASS(de != NULL);
534 
535 	/* Files marked as immutable or append-only cannot be deleted. */
536 	if ((node->tn_flags & (IMMUTABLE | APPEND | NOUNLINK)) ||
537 	    (dnode->tn_flags & APPEND)) {
538 		error = EPERM;
539 		goto out;
540 	}
541 
542 	/* Remove the entry from the directory; as it is a file, we do not
543 	 * have to change the number of hard links of the directory. */
544 	tmpfs_dir_detach(dvp, de);
545 	if (v->a_cnp->cn_flags & DOWHITEOUT)
546 		tmpfs_dir_whiteout_add(dvp, v->a_cnp);
547 
548 	/* Free the directory entry we just deleted.  Note that the node
549 	 * referred by it will not be removed until the vnode is really
550 	 * reclaimed. */
551 	tmpfs_free_dirent(tmp, de);
552 
553 	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED;
554 	error = 0;
555 
556 out:
557 
558 	return error;
559 }
560 
561 static int
562 tmpfs_link(struct vop_link_args *v)
563 {
564 	struct vnode *dvp = v->a_tdvp;
565 	struct vnode *vp = v->a_vp;
566 	struct componentname *cnp = v->a_cnp;
567 
568 	int error;
569 	struct tmpfs_dirent *de;
570 	struct tmpfs_node *node;
571 
572 	MPASS(VOP_ISLOCKED(dvp));
573 	MPASS(cnp->cn_flags & HASBUF);
574 	MPASS(dvp != vp); /* XXX When can this be false? */
575 	node = VP_TO_TMPFS_NODE(vp);
576 
577 	/* Ensure that we do not overflow the maximum number of links imposed
578 	 * by the system. */
579 	MPASS(node->tn_links <= LINK_MAX);
580 	if (node->tn_links == LINK_MAX) {
581 		error = EMLINK;
582 		goto out;
583 	}
584 
585 	/* We cannot create links of files marked immutable or append-only. */
586 	if (node->tn_flags & (IMMUTABLE | APPEND)) {
587 		error = EPERM;
588 		goto out;
589 	}
590 
591 	/* Allocate a new directory entry to represent the node. */
592 	error = tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount), node,
593 	    cnp->cn_nameptr, cnp->cn_namelen, &de);
594 	if (error != 0)
595 		goto out;
596 
597 	/* Insert the new directory entry into the appropriate directory. */
598 	if (cnp->cn_flags & ISWHITEOUT)
599 		tmpfs_dir_whiteout_remove(dvp, cnp);
600 	tmpfs_dir_attach(dvp, de);
601 
602 	/* vp link count has changed, so update node times. */
603 	node->tn_status |= TMPFS_NODE_CHANGED;
604 	tmpfs_update(vp);
605 
606 	error = 0;
607 
608 out:
609 	return error;
610 }
611 
612 /*
613  * We acquire all but fdvp locks using non-blocking acquisitions.  If we
614  * fail to acquire any lock in the path we will drop all held locks,
615  * acquire the new lock in a blocking fashion, and then release it and
616  * restart the rename.  This acquire/release step ensures that we do not
617  * spin on a lock waiting for release.  On error release all vnode locks
618  * and decrement references the way tmpfs_rename() would do.
619  */
620 static int
621 tmpfs_rename_relock(struct vnode *fdvp, struct vnode **fvpp,
622     struct vnode *tdvp, struct vnode **tvpp,
623     struct componentname *fcnp, struct componentname *tcnp)
624 {
625 	struct vnode *nvp;
626 	struct mount *mp;
627 	struct tmpfs_dirent *de;
628 	int error, restarts = 0;
629 
630 	VOP_UNLOCK(tdvp, 0);
631 	if (*tvpp != NULL && *tvpp != tdvp)
632 		VOP_UNLOCK(*tvpp, 0);
633 	mp = fdvp->v_mount;
634 
635 relock:
636 	restarts += 1;
637 	error = vn_lock(fdvp, LK_EXCLUSIVE);
638 	if (error)
639 		goto releout;
640 	if (vn_lock(tdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
641 		VOP_UNLOCK(fdvp, 0);
642 		error = vn_lock(tdvp, LK_EXCLUSIVE);
643 		if (error)
644 			goto releout;
645 		VOP_UNLOCK(tdvp, 0);
646 		goto relock;
647 	}
648 	/*
649 	 * Re-resolve fvp to be certain it still exists and fetch the
650 	 * correct vnode.
651 	 */
652 	de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(fdvp), NULL, fcnp);
653 	if (de == NULL) {
654 		VOP_UNLOCK(fdvp, 0);
655 		VOP_UNLOCK(tdvp, 0);
656 		if ((fcnp->cn_flags & ISDOTDOT) != 0 ||
657 		    (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.'))
658 			error = EINVAL;
659 		else
660 			error = ENOENT;
661 		goto releout;
662 	}
663 	error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp);
664 	if (error != 0) {
665 		VOP_UNLOCK(fdvp, 0);
666 		VOP_UNLOCK(tdvp, 0);
667 		if (error != EBUSY)
668 			goto releout;
669 		error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp);
670 		if (error != 0)
671 			goto releout;
672 		VOP_UNLOCK(nvp, 0);
673 		/*
674 		 * Concurrent rename race.
675 		 */
676 		if (nvp == tdvp) {
677 			vrele(nvp);
678 			error = EINVAL;
679 			goto releout;
680 		}
681 		vrele(*fvpp);
682 		*fvpp = nvp;
683 		goto relock;
684 	}
685 	vrele(*fvpp);
686 	*fvpp = nvp;
687 	VOP_UNLOCK(*fvpp, 0);
688 	/*
689 	 * Re-resolve tvp and acquire the vnode lock if present.
690 	 */
691 	de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(tdvp), NULL, tcnp);
692 	/*
693 	 * If tvp disappeared we just carry on.
694 	 */
695 	if (de == NULL && *tvpp != NULL) {
696 		vrele(*tvpp);
697 		*tvpp = NULL;
698 	}
699 	/*
700 	 * Get the tvp ino if the lookup succeeded.  We may have to restart
701 	 * if the non-blocking acquire fails.
702 	 */
703 	if (de != NULL) {
704 		nvp = NULL;
705 		error = tmpfs_alloc_vp(mp, de->td_node,
706 		    LK_EXCLUSIVE | LK_NOWAIT, &nvp);
707 		if (*tvpp != NULL)
708 			vrele(*tvpp);
709 		*tvpp = nvp;
710 		if (error != 0) {
711 			VOP_UNLOCK(fdvp, 0);
712 			VOP_UNLOCK(tdvp, 0);
713 			if (error != EBUSY)
714 				goto releout;
715 			error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE,
716 			    &nvp);
717 			if (error != 0)
718 				goto releout;
719 			VOP_UNLOCK(nvp, 0);
720 			/*
721 			 * fdvp contains fvp, thus tvp (=fdvp) is not empty.
722 			 */
723 			if (nvp == fdvp) {
724 				error = ENOTEMPTY;
725 				goto releout;
726 			}
727 			goto relock;
728 		}
729 	}
730 	tmpfs_rename_restarts += restarts;
731 
732 	return (0);
733 
734 releout:
735 	vrele(fdvp);
736 	vrele(*fvpp);
737 	vrele(tdvp);
738 	if (*tvpp != NULL)
739 		vrele(*tvpp);
740 	tmpfs_rename_restarts += restarts;
741 
742 	return (error);
743 }
744 
745 static int
746 tmpfs_rename(struct vop_rename_args *v)
747 {
748 	struct vnode *fdvp = v->a_fdvp;
749 	struct vnode *fvp = v->a_fvp;
750 	struct componentname *fcnp = v->a_fcnp;
751 	struct vnode *tdvp = v->a_tdvp;
752 	struct vnode *tvp = v->a_tvp;
753 	struct componentname *tcnp = v->a_tcnp;
754 	struct mount *mp = NULL;
755 
756 	char *newname;
757 	int error;
758 	struct tmpfs_dirent *de;
759 	struct tmpfs_mount *tmp;
760 	struct tmpfs_node *fdnode;
761 	struct tmpfs_node *fnode;
762 	struct tmpfs_node *tnode;
763 	struct tmpfs_node *tdnode;
764 
765 	MPASS(VOP_ISLOCKED(tdvp));
766 	MPASS(IMPLIES(tvp != NULL, VOP_ISLOCKED(tvp)));
767 	MPASS(fcnp->cn_flags & HASBUF);
768 	MPASS(tcnp->cn_flags & HASBUF);
769 
770 	/* Disallow cross-device renames.
771 	 * XXX Why isn't this done by the caller? */
772 	if (fvp->v_mount != tdvp->v_mount ||
773 	    (tvp != NULL && fvp->v_mount != tvp->v_mount)) {
774 		error = EXDEV;
775 		goto out;
776 	}
777 
778 	/* If source and target are the same file, there is nothing to do. */
779 	if (fvp == tvp) {
780 		error = 0;
781 		goto out;
782 	}
783 
784 	/* If we need to move the directory between entries, lock the
785 	 * source so that we can safely operate on it. */
786 	if (fdvp != tdvp && fdvp != tvp) {
787 		if (vn_lock(fdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
788 			mp = tdvp->v_mount;
789 			error = vfs_busy(mp, 0);
790 			if (error != 0) {
791 				mp = NULL;
792 				goto out;
793 			}
794 			error = tmpfs_rename_relock(fdvp, &fvp, tdvp, &tvp,
795 			    fcnp, tcnp);
796 			if (error != 0) {
797 				vfs_unbusy(mp);
798 				return (error);
799 			}
800 			ASSERT_VOP_ELOCKED(fdvp,
801 			    "tmpfs_rename: fdvp not locked");
802 			ASSERT_VOP_ELOCKED(tdvp,
803 			    "tmpfs_rename: tdvp not locked");
804 			if (tvp != NULL)
805 				ASSERT_VOP_ELOCKED(tvp,
806 				    "tmpfs_rename: tvp not locked");
807 			if (fvp == tvp) {
808 				error = 0;
809 				goto out_locked;
810 			}
811 		}
812 	}
813 
814 	tmp = VFS_TO_TMPFS(tdvp->v_mount);
815 	tdnode = VP_TO_TMPFS_DIR(tdvp);
816 	tnode = (tvp == NULL) ? NULL : VP_TO_TMPFS_NODE(tvp);
817 	fdnode = VP_TO_TMPFS_DIR(fdvp);
818 	fnode = VP_TO_TMPFS_NODE(fvp);
819 	de = tmpfs_dir_lookup(fdnode, fnode, fcnp);
820 
821 	/* Entry can disappear before we lock fdvp,
822 	 * also avoid manipulating '.' and '..' entries. */
823 	if (de == NULL) {
824 		if ((fcnp->cn_flags & ISDOTDOT) != 0 ||
825 		    (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.'))
826 			error = EINVAL;
827 		else
828 			error = ENOENT;
829 		goto out_locked;
830 	}
831 	MPASS(de->td_node == fnode);
832 
833 	/* If re-naming a directory to another preexisting directory
834 	 * ensure that the target directory is empty so that its
835 	 * removal causes no side effects.
836 	 * Kern_rename gurantees the destination to be a directory
837 	 * if the source is one. */
838 	if (tvp != NULL) {
839 		MPASS(tnode != NULL);
840 
841 		if ((tnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
842 		    (tdnode->tn_flags & (APPEND | IMMUTABLE))) {
843 			error = EPERM;
844 			goto out_locked;
845 		}
846 
847 		if (fnode->tn_type == VDIR && tnode->tn_type == VDIR) {
848 			if (tnode->tn_size > 0) {
849 				error = ENOTEMPTY;
850 				goto out_locked;
851 			}
852 		} else if (fnode->tn_type == VDIR && tnode->tn_type != VDIR) {
853 			error = ENOTDIR;
854 			goto out_locked;
855 		} else if (fnode->tn_type != VDIR && tnode->tn_type == VDIR) {
856 			error = EISDIR;
857 			goto out_locked;
858 		} else {
859 			MPASS(fnode->tn_type != VDIR &&
860 				tnode->tn_type != VDIR);
861 		}
862 	}
863 
864 	if ((fnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))
865 	    || (fdnode->tn_flags & (APPEND | IMMUTABLE))) {
866 		error = EPERM;
867 		goto out_locked;
868 	}
869 
870 	/* Ensure that we have enough memory to hold the new name, if it
871 	 * has to be changed. */
872 	if (fcnp->cn_namelen != tcnp->cn_namelen ||
873 	    bcmp(fcnp->cn_nameptr, tcnp->cn_nameptr, fcnp->cn_namelen) != 0) {
874 		newname = malloc(tcnp->cn_namelen, M_TMPFSNAME, M_WAITOK);
875 	} else
876 		newname = NULL;
877 
878 	/* If the node is being moved to another directory, we have to do
879 	 * the move. */
880 	if (fdnode != tdnode) {
881 		/* In case we are moving a directory, we have to adjust its
882 		 * parent to point to the new parent. */
883 		if (de->td_node->tn_type == VDIR) {
884 			struct tmpfs_node *n;
885 
886 			/* Ensure the target directory is not a child of the
887 			 * directory being moved.  Otherwise, we'd end up
888 			 * with stale nodes. */
889 			n = tdnode;
890 			/* TMPFS_LOCK garanties that no nodes are freed while
891 			 * traversing the list. Nodes can only be marked as
892 			 * removed: tn_parent == NULL. */
893 			TMPFS_LOCK(tmp);
894 			TMPFS_NODE_LOCK(n);
895 			while (n != n->tn_dir.tn_parent) {
896 				struct tmpfs_node *parent;
897 
898 				if (n == fnode) {
899 					TMPFS_NODE_UNLOCK(n);
900 					TMPFS_UNLOCK(tmp);
901 					error = EINVAL;
902 					if (newname != NULL)
903 						    free(newname, M_TMPFSNAME);
904 					goto out_locked;
905 				}
906 				parent = n->tn_dir.tn_parent;
907 				TMPFS_NODE_UNLOCK(n);
908 				if (parent == NULL) {
909 					n = NULL;
910 					break;
911 				}
912 				TMPFS_NODE_LOCK(parent);
913 				if (parent->tn_dir.tn_parent == NULL) {
914 					TMPFS_NODE_UNLOCK(parent);
915 					n = NULL;
916 					break;
917 				}
918 				n = parent;
919 			}
920 			TMPFS_UNLOCK(tmp);
921 			if (n == NULL) {
922 				error = EINVAL;
923 				if (newname != NULL)
924 					    free(newname, M_TMPFSNAME);
925 				goto out_locked;
926 			}
927 			TMPFS_NODE_UNLOCK(n);
928 
929 			/* Adjust the parent pointer. */
930 			TMPFS_VALIDATE_DIR(fnode);
931 			TMPFS_NODE_LOCK(de->td_node);
932 			de->td_node->tn_dir.tn_parent = tdnode;
933 			TMPFS_NODE_UNLOCK(de->td_node);
934 
935 			/* As a result of changing the target of the '..'
936 			 * entry, the link count of the source and target
937 			 * directories has to be adjusted. */
938 			TMPFS_NODE_LOCK(tdnode);
939 			TMPFS_ASSERT_LOCKED(tdnode);
940 			tdnode->tn_links++;
941 			TMPFS_NODE_UNLOCK(tdnode);
942 
943 			TMPFS_NODE_LOCK(fdnode);
944 			TMPFS_ASSERT_LOCKED(fdnode);
945 			fdnode->tn_links--;
946 			TMPFS_NODE_UNLOCK(fdnode);
947 		}
948 	}
949 
950 	/* Do the move: just remove the entry from the source directory
951 	 * and insert it into the target one. */
952 	tmpfs_dir_detach(fdvp, de);
953 
954 	if (fcnp->cn_flags & DOWHITEOUT)
955 		tmpfs_dir_whiteout_add(fdvp, fcnp);
956 	if (tcnp->cn_flags & ISWHITEOUT)
957 		tmpfs_dir_whiteout_remove(tdvp, tcnp);
958 
959 	/* If the name has changed, we need to make it effective by changing
960 	 * it in the directory entry. */
961 	if (newname != NULL) {
962 		MPASS(tcnp->cn_namelen <= MAXNAMLEN);
963 
964 		free(de->ud.td_name, M_TMPFSNAME);
965 		de->ud.td_name = newname;
966 		tmpfs_dirent_init(de, tcnp->cn_nameptr, tcnp->cn_namelen);
967 
968 		fnode->tn_status |= TMPFS_NODE_CHANGED;
969 		tdnode->tn_status |= TMPFS_NODE_MODIFIED;
970 	}
971 
972 	/* If we are overwriting an entry, we have to remove the old one
973 	 * from the target directory. */
974 	if (tvp != NULL) {
975 		struct tmpfs_dirent *tde;
976 
977 		/* Remove the old entry from the target directory. */
978 		tde = tmpfs_dir_lookup(tdnode, tnode, tcnp);
979 		tmpfs_dir_detach(tdvp, tde);
980 
981 		/* Free the directory entry we just deleted.  Note that the
982 		 * node referred by it will not be removed until the vnode is
983 		 * really reclaimed. */
984 		tmpfs_free_dirent(VFS_TO_TMPFS(tvp->v_mount), tde);
985 	}
986 
987 	tmpfs_dir_attach(tdvp, de);
988 
989 	cache_purge(fvp);
990 	if (tvp != NULL)
991 		cache_purge(tvp);
992 	cache_purge_negative(tdvp);
993 
994 	error = 0;
995 
996 out_locked:
997 	if (fdvp != tdvp && fdvp != tvp)
998 		VOP_UNLOCK(fdvp, 0);
999 
1000 out:
1001 	/* Release target nodes. */
1002 	/* XXX: I don't understand when tdvp can be the same as tvp, but
1003 	 * other code takes care of this... */
1004 	if (tdvp == tvp)
1005 		vrele(tdvp);
1006 	else
1007 		vput(tdvp);
1008 	if (tvp != NULL)
1009 		vput(tvp);
1010 
1011 	/* Release source nodes. */
1012 	vrele(fdvp);
1013 	vrele(fvp);
1014 
1015 	if (mp != NULL)
1016 		vfs_unbusy(mp);
1017 
1018 	return error;
1019 }
1020 
1021 static int
1022 tmpfs_mkdir(struct vop_mkdir_args *v)
1023 {
1024 	struct vnode *dvp = v->a_dvp;
1025 	struct vnode **vpp = v->a_vpp;
1026 	struct componentname *cnp = v->a_cnp;
1027 	struct vattr *vap = v->a_vap;
1028 
1029 	MPASS(vap->va_type == VDIR);
1030 
1031 	return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
1032 }
1033 
1034 static int
1035 tmpfs_rmdir(struct vop_rmdir_args *v)
1036 {
1037 	struct vnode *dvp = v->a_dvp;
1038 	struct vnode *vp = v->a_vp;
1039 
1040 	int error;
1041 	struct tmpfs_dirent *de;
1042 	struct tmpfs_mount *tmp;
1043 	struct tmpfs_node *dnode;
1044 	struct tmpfs_node *node;
1045 
1046 	MPASS(VOP_ISLOCKED(dvp));
1047 	MPASS(VOP_ISLOCKED(vp));
1048 
1049 	tmp = VFS_TO_TMPFS(dvp->v_mount);
1050 	dnode = VP_TO_TMPFS_DIR(dvp);
1051 	node = VP_TO_TMPFS_DIR(vp);
1052 
1053 	/* Directories with more than two entries ('.' and '..') cannot be
1054 	 * removed. */
1055 	 if (node->tn_size > 0) {
1056 		 error = ENOTEMPTY;
1057 		 goto out;
1058 	 }
1059 
1060 	if ((dnode->tn_flags & APPEND)
1061 	    || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
1062 		error = EPERM;
1063 		goto out;
1064 	}
1065 
1066 	/* This invariant holds only if we are not trying to remove "..".
1067 	  * We checked for that above so this is safe now. */
1068 	MPASS(node->tn_dir.tn_parent == dnode);
1069 
1070 	/* Get the directory entry associated with node (vp).  This was
1071 	 * filled by tmpfs_lookup while looking up the entry. */
1072 	de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
1073 	MPASS(TMPFS_DIRENT_MATCHES(de,
1074 	    v->a_cnp->cn_nameptr,
1075 	    v->a_cnp->cn_namelen));
1076 
1077 	/* Check flags to see if we are allowed to remove the directory. */
1078 	if (dnode->tn_flags & APPEND
1079 		|| node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) {
1080 		error = EPERM;
1081 		goto out;
1082 	}
1083 
1084 
1085 	/* Detach the directory entry from the directory (dnode). */
1086 	tmpfs_dir_detach(dvp, de);
1087 	if (v->a_cnp->cn_flags & DOWHITEOUT)
1088 		tmpfs_dir_whiteout_add(dvp, v->a_cnp);
1089 
1090 	/* No vnode should be allocated for this entry from this point */
1091 	TMPFS_NODE_LOCK(node);
1092 	TMPFS_ASSERT_ELOCKED(node);
1093 	node->tn_links--;
1094 	node->tn_dir.tn_parent = NULL;
1095 	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | \
1096 	    TMPFS_NODE_MODIFIED;
1097 
1098 	TMPFS_NODE_UNLOCK(node);
1099 
1100 	TMPFS_NODE_LOCK(dnode);
1101 	TMPFS_ASSERT_ELOCKED(dnode);
1102 	dnode->tn_links--;
1103 	dnode->tn_status |= TMPFS_NODE_ACCESSED | \
1104 	    TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED;
1105 	TMPFS_NODE_UNLOCK(dnode);
1106 
1107 	cache_purge(dvp);
1108 	cache_purge(vp);
1109 
1110 	/* Free the directory entry we just deleted.  Note that the node
1111 	 * referred by it will not be removed until the vnode is really
1112 	 * reclaimed. */
1113 	tmpfs_free_dirent(tmp, de);
1114 
1115 	/* Release the deleted vnode (will destroy the node, notify
1116 	 * interested parties and clean it from the cache). */
1117 
1118 	dnode->tn_status |= TMPFS_NODE_CHANGED;
1119 	tmpfs_update(dvp);
1120 
1121 	error = 0;
1122 
1123 out:
1124 	return error;
1125 }
1126 
1127 static int
1128 tmpfs_symlink(struct vop_symlink_args *v)
1129 {
1130 	struct vnode *dvp = v->a_dvp;
1131 	struct vnode **vpp = v->a_vpp;
1132 	struct componentname *cnp = v->a_cnp;
1133 	struct vattr *vap = v->a_vap;
1134 	char *target = v->a_target;
1135 
1136 #ifdef notyet /* XXX FreeBSD BUG: kern_symlink is not setting VLNK */
1137 	MPASS(vap->va_type == VLNK);
1138 #else
1139 	vap->va_type = VLNK;
1140 #endif
1141 
1142 	return tmpfs_alloc_file(dvp, vpp, vap, cnp, target);
1143 }
1144 
1145 static int
1146 tmpfs_readdir(struct vop_readdir_args *v)
1147 {
1148 	struct vnode *vp = v->a_vp;
1149 	struct uio *uio = v->a_uio;
1150 	int *eofflag = v->a_eofflag;
1151 	u_long **cookies = v->a_cookies;
1152 	int *ncookies = v->a_ncookies;
1153 
1154 	int error;
1155 	ssize_t startresid;
1156 	int maxcookies;
1157 	struct tmpfs_node *node;
1158 
1159 	/* This operation only makes sense on directory nodes. */
1160 	if (vp->v_type != VDIR)
1161 		return ENOTDIR;
1162 
1163 	maxcookies = 0;
1164 	node = VP_TO_TMPFS_DIR(vp);
1165 
1166 	startresid = uio->uio_resid;
1167 
1168 	/* Allocate cookies for NFS and compat modules. */
1169 	if (cookies != NULL && ncookies != NULL) {
1170 		maxcookies = howmany(node->tn_size,
1171 		    sizeof(struct tmpfs_dirent)) + 2;
1172 		*cookies = malloc(maxcookies * sizeof(**cookies), M_TEMP,
1173 		    M_WAITOK);
1174 		*ncookies = 0;
1175 	}
1176 
1177 	if (cookies == NULL)
1178 		error = tmpfs_dir_getdents(node, uio, 0, NULL, NULL);
1179 	else
1180 		error = tmpfs_dir_getdents(node, uio, maxcookies, *cookies,
1181 		    ncookies);
1182 
1183 	/* Buffer was filled without hitting EOF. */
1184 	if (error == EJUSTRETURN)
1185 		error = (uio->uio_resid != startresid) ? 0 : EINVAL;
1186 
1187 	if (error != 0 && cookies != NULL)
1188 		free(*cookies, M_TEMP);
1189 
1190 	if (eofflag != NULL)
1191 		*eofflag =
1192 		    (error == 0 && uio->uio_offset == TMPFS_DIRCOOKIE_EOF);
1193 
1194 	return error;
1195 }
1196 
1197 static int
1198 tmpfs_readlink(struct vop_readlink_args *v)
1199 {
1200 	struct vnode *vp = v->a_vp;
1201 	struct uio *uio = v->a_uio;
1202 
1203 	int error;
1204 	struct tmpfs_node *node;
1205 
1206 	MPASS(uio->uio_offset == 0);
1207 	MPASS(vp->v_type == VLNK);
1208 
1209 	node = VP_TO_TMPFS_NODE(vp);
1210 
1211 	error = uiomove(node->tn_link, MIN(node->tn_size, uio->uio_resid),
1212 	    uio);
1213 	node->tn_status |= TMPFS_NODE_ACCESSED;
1214 
1215 	return error;
1216 }
1217 
1218 static int
1219 tmpfs_inactive(struct vop_inactive_args *v)
1220 {
1221 	struct vnode *vp = v->a_vp;
1222 
1223 	struct tmpfs_node *node;
1224 
1225 	node = VP_TO_TMPFS_NODE(vp);
1226 
1227 	if (node->tn_links == 0)
1228 		vrecycle(vp);
1229 
1230 	return 0;
1231 }
1232 
1233 int
1234 tmpfs_reclaim(struct vop_reclaim_args *v)
1235 {
1236 	struct vnode *vp = v->a_vp;
1237 
1238 	struct tmpfs_mount *tmp;
1239 	struct tmpfs_node *node;
1240 
1241 	node = VP_TO_TMPFS_NODE(vp);
1242 	tmp = VFS_TO_TMPFS(vp->v_mount);
1243 
1244 	if (vp->v_type == VREG)
1245 		tmpfs_destroy_vobject(vp, node->tn_reg.tn_aobj);
1246 	else
1247 		vnode_destroy_vobject(vp);
1248 	vp->v_object = NULL;
1249 	cache_purge(vp);
1250 
1251 	TMPFS_NODE_LOCK(node);
1252 	TMPFS_ASSERT_ELOCKED(node);
1253 	tmpfs_free_vp(vp);
1254 
1255 	/* If the node referenced by this vnode was deleted by the user,
1256 	 * we must free its associated data structures (now that the vnode
1257 	 * is being reclaimed). */
1258 	if (node->tn_links == 0 &&
1259 	    (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) {
1260 		node->tn_vpstate = TMPFS_VNODE_DOOMED;
1261 		TMPFS_NODE_UNLOCK(node);
1262 		tmpfs_free_node(tmp, node);
1263 	} else
1264 		TMPFS_NODE_UNLOCK(node);
1265 
1266 	MPASS(vp->v_data == NULL);
1267 	return 0;
1268 }
1269 
1270 static int
1271 tmpfs_print(struct vop_print_args *v)
1272 {
1273 	struct vnode *vp = v->a_vp;
1274 
1275 	struct tmpfs_node *node;
1276 
1277 	node = VP_TO_TMPFS_NODE(vp);
1278 
1279 	printf("tag VT_TMPFS, tmpfs_node %p, flags 0x%lx, links %d\n",
1280 	    node, node->tn_flags, node->tn_links);
1281 	printf("\tmode 0%o, owner %d, group %d, size %jd, status 0x%x\n",
1282 	    node->tn_mode, node->tn_uid, node->tn_gid,
1283 	    (intmax_t)node->tn_size, node->tn_status);
1284 
1285 	if (vp->v_type == VFIFO)
1286 		fifo_printinfo(vp);
1287 
1288 	printf("\n");
1289 
1290 	return 0;
1291 }
1292 
1293 static int
1294 tmpfs_pathconf(struct vop_pathconf_args *v)
1295 {
1296 	int name = v->a_name;
1297 	register_t *retval = v->a_retval;
1298 
1299 	int error;
1300 
1301 	error = 0;
1302 
1303 	switch (name) {
1304 	case _PC_LINK_MAX:
1305 		*retval = LINK_MAX;
1306 		break;
1307 
1308 	case _PC_NAME_MAX:
1309 		*retval = NAME_MAX;
1310 		break;
1311 
1312 	case _PC_PATH_MAX:
1313 		*retval = PATH_MAX;
1314 		break;
1315 
1316 	case _PC_PIPE_BUF:
1317 		*retval = PIPE_BUF;
1318 		break;
1319 
1320 	case _PC_CHOWN_RESTRICTED:
1321 		*retval = 1;
1322 		break;
1323 
1324 	case _PC_NO_TRUNC:
1325 		*retval = 1;
1326 		break;
1327 
1328 	case _PC_SYNC_IO:
1329 		*retval = 1;
1330 		break;
1331 
1332 	case _PC_FILESIZEBITS:
1333 		*retval = 0; /* XXX Don't know which value should I return. */
1334 		break;
1335 
1336 	default:
1337 		error = EINVAL;
1338 	}
1339 
1340 	return error;
1341 }
1342 
1343 static int
1344 tmpfs_vptofh(struct vop_vptofh_args *ap)
1345 {
1346 	struct tmpfs_fid *tfhp;
1347 	struct tmpfs_node *node;
1348 
1349 	tfhp = (struct tmpfs_fid *)ap->a_fhp;
1350 	node = VP_TO_TMPFS_NODE(ap->a_vp);
1351 
1352 	tfhp->tf_len = sizeof(struct tmpfs_fid);
1353 	tfhp->tf_id = node->tn_id;
1354 	tfhp->tf_gen = node->tn_gen;
1355 
1356 	return (0);
1357 }
1358 
1359 static int
1360 tmpfs_whiteout(struct vop_whiteout_args *ap)
1361 {
1362 	struct vnode *dvp = ap->a_dvp;
1363 	struct componentname *cnp = ap->a_cnp;
1364 	struct tmpfs_dirent *de;
1365 
1366 	switch (ap->a_flags) {
1367 	case LOOKUP:
1368 		return (0);
1369 	case CREATE:
1370 		de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(dvp), NULL, cnp);
1371 		if (de != NULL)
1372 			return (de->td_node == NULL ? 0 : EEXIST);
1373 		return (tmpfs_dir_whiteout_add(dvp, cnp));
1374 	case DELETE:
1375 		tmpfs_dir_whiteout_remove(dvp, cnp);
1376 		return (0);
1377 	default:
1378 		panic("tmpfs_whiteout: unknown op");
1379 	}
1380 }
1381 
1382 /*
1383  * vnode operations vector used for files stored in a tmpfs file system.
1384  */
1385 struct vop_vector tmpfs_vnodeop_entries = {
1386 	.vop_default =			&default_vnodeops,
1387 	.vop_lookup =			vfs_cache_lookup,
1388 	.vop_cachedlookup =		tmpfs_lookup,
1389 	.vop_create =			tmpfs_create,
1390 	.vop_mknod =			tmpfs_mknod,
1391 	.vop_open =			tmpfs_open,
1392 	.vop_close =			tmpfs_close,
1393 	.vop_access =			tmpfs_access,
1394 	.vop_getattr =			tmpfs_getattr,
1395 	.vop_setattr =			tmpfs_setattr,
1396 	.vop_read =			tmpfs_read,
1397 	.vop_write =			tmpfs_write,
1398 	.vop_fsync =			tmpfs_fsync,
1399 	.vop_remove =			tmpfs_remove,
1400 	.vop_link =			tmpfs_link,
1401 	.vop_rename =			tmpfs_rename,
1402 	.vop_mkdir =			tmpfs_mkdir,
1403 	.vop_rmdir =			tmpfs_rmdir,
1404 	.vop_symlink =			tmpfs_symlink,
1405 	.vop_readdir =			tmpfs_readdir,
1406 	.vop_readlink =			tmpfs_readlink,
1407 	.vop_inactive =			tmpfs_inactive,
1408 	.vop_reclaim =			tmpfs_reclaim,
1409 	.vop_print =			tmpfs_print,
1410 	.vop_pathconf =			tmpfs_pathconf,
1411 	.vop_vptofh =			tmpfs_vptofh,
1412 	.vop_whiteout =			tmpfs_whiteout,
1413 	.vop_bmap =			VOP_EOPNOTSUPP,
1414 };
1415 
1416