1/*	$NetBSD: tmpfs_vnops.c,v 1.150 2022/06/01 08:42:38 hannken Exp $	*/
2
3/*
4 * Copyright (c) 2005, 2006, 2007, 2020 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
37#include <sys/cdefs.h>
38__KERNEL_RCSID(0, "$NetBSD: tmpfs_vnops.c,v 1.150 2022/06/01 08:42:38 hannken Exp $");
39
40#include <sys/param.h>
41#include <sys/dirent.h>
42#include <sys/fcntl.h>
43#include <sys/event.h>
44#include <sys/malloc.h>
45#include <sys/namei.h>
46#include <sys/stat.h>
47#include <sys/uio.h>
48#include <sys/unistd.h>
49#include <sys/vnode.h>
50#include <sys/lockf.h>
51#include <sys/kauth.h>
52#include <sys/atomic.h>
53
54#include <uvm/uvm_object.h>
55
56#include <miscfs/fifofs/fifo.h>
57#include <miscfs/genfs/genfs.h>
58#include <fs/tmpfs/tmpfs_vnops.h>
59#include <fs/tmpfs/tmpfs.h>
60
61/*
62 * vnode operations vector used for files stored in a tmpfs file system.
63 */
64int (**tmpfs_vnodeop_p)(void *);
65const struct vnodeopv_entry_desc tmpfs_vnodeop_entries[] = {
66	{ &vop_default_desc,		vn_default_error },
67	{ &vop_parsepath_desc,		genfs_parsepath },
68	{ &vop_lookup_desc,		tmpfs_lookup },
69	{ &vop_create_desc,		tmpfs_create },
70	{ &vop_mknod_desc,		tmpfs_mknod },
71	{ &vop_open_desc,		tmpfs_open },
72	{ &vop_close_desc,		tmpfs_close },
73	{ &vop_access_desc,		tmpfs_access },
74	{ &vop_accessx_desc,		genfs_accessx },
75	{ &vop_getattr_desc,		tmpfs_getattr },
76	{ &vop_setattr_desc,		tmpfs_setattr },
77	{ &vop_read_desc,		tmpfs_read },
78	{ &vop_write_desc,		tmpfs_write },
79	{ &vop_fallocate_desc,		genfs_eopnotsupp },
80	{ &vop_fdiscard_desc,		genfs_eopnotsupp },
81	{ &vop_ioctl_desc,		genfs_enoioctl },
82	{ &vop_fcntl_desc,		genfs_fcntl },
83	{ &vop_poll_desc,		genfs_poll },
84	{ &vop_kqfilter_desc,		genfs_kqfilter },
85	{ &vop_revoke_desc,		genfs_revoke },
86	{ &vop_mmap_desc,		genfs_mmap },
87	{ &vop_fsync_desc,		tmpfs_fsync },
88	{ &vop_seek_desc,		genfs_seek },
89	{ &vop_remove_desc,		tmpfs_remove },
90	{ &vop_link_desc,		tmpfs_link },
91	{ &vop_rename_desc,		tmpfs_rename },
92	{ &vop_mkdir_desc,		tmpfs_mkdir },
93	{ &vop_rmdir_desc,		tmpfs_rmdir },
94	{ &vop_symlink_desc,		tmpfs_symlink },
95	{ &vop_readdir_desc,		tmpfs_readdir },
96	{ &vop_readlink_desc,		tmpfs_readlink },
97	{ &vop_abortop_desc,		genfs_abortop },
98	{ &vop_inactive_desc,		tmpfs_inactive },
99	{ &vop_reclaim_desc,		tmpfs_reclaim },
100	{ &vop_lock_desc,		genfs_lock },
101	{ &vop_unlock_desc,		genfs_unlock },
102	{ &vop_bmap_desc,		genfs_eopnotsupp },
103	{ &vop_strategy_desc,		genfs_eopnotsupp },
104	{ &vop_print_desc,		tmpfs_print },
105	{ &vop_pathconf_desc,		tmpfs_pathconf },
106	{ &vop_islocked_desc,		genfs_islocked },
107	{ &vop_advlock_desc,		tmpfs_advlock },
108	{ &vop_bwrite_desc,		genfs_nullop },
109	{ &vop_getpages_desc,		tmpfs_getpages },
110	{ &vop_putpages_desc,		tmpfs_putpages },
111	{ &vop_whiteout_desc,		tmpfs_whiteout },
112	{ NULL, NULL }
113};
114
115const struct vnodeopv_desc tmpfs_vnodeop_opv_desc = {
116	&tmpfs_vnodeop_p, tmpfs_vnodeop_entries
117};
118
119/*
120 * tmpfs_lookup: path name traversal routine.
121 *
122 * Arguments: dvp (directory being searched), vpp (result),
123 * cnp (component name - path).
124 *
125 * => Caller holds a reference and lock on dvp.
126 * => We return looked-up vnode (vpp) locked, with a reference held.
127 */
128int
129tmpfs_lookup(void *v)
130{
131	struct vop_lookup_v2_args /* {
132		struct vnode *a_dvp;
133		struct vnode **a_vpp;
134		struct componentname *a_cnp;
135	} */ *ap = v;
136	vnode_t *dvp = ap->a_dvp, **vpp = ap->a_vpp;
137	struct componentname *cnp = ap->a_cnp;
138	const bool lastcn = (cnp->cn_flags & ISLASTCN) != 0;
139	tmpfs_node_t *dnode, *tnode;
140	tmpfs_dirent_t *de;
141	int cachefound, iswhiteout;
142	int error;
143
144	KASSERT(VOP_ISLOCKED(dvp));
145
146	dnode = VP_TO_TMPFS_DIR(dvp);
147	*vpp = NULL;
148
149	/* Check accessibility of directory. */
150	error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred);
151	if (error) {
152		goto out;
153	}
154
155	/*
156	 * If requesting the last path component on a read-only file system
157	 * with a write operation, deny it.
158	 */
159	if (lastcn && (dvp->v_mount->mnt_flag & MNT_RDONLY) != 0 &&
160	    (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
161		error = EROFS;
162		goto out;
163	}
164
165	/*
166	 * Avoid doing a linear scan of the directory if the requested
167	 * directory/name couple is already in the cache.
168	 */
169	cachefound = cache_lookup(dvp, cnp->cn_nameptr, cnp->cn_namelen,
170				  cnp->cn_nameiop, cnp->cn_flags,
171				  &iswhiteout, vpp);
172	if (iswhiteout) {
173		cnp->cn_flags |= ISWHITEOUT;
174	}
175	if (cachefound && *vpp == NULLVP) {
176		/* Negative cache hit. */
177		error = ENOENT;
178		goto out;
179	} else if (cachefound) {
180		error = 0;
181		goto out;
182	}
183
184	/*
185	 * Treat an unlinked directory as empty (no "." or "..")
186	 */
187	if (dnode->tn_links == 0) {
188		KASSERT(dnode->tn_size == 0);
189		error = ENOENT;
190		goto out;
191	}
192
193	if (cnp->cn_flags & ISDOTDOT) {
194		tmpfs_node_t *pnode;
195
196		/*
197		 * Lookup of ".." case.
198		 */
199		if (lastcn && cnp->cn_nameiop == RENAME) {
200			error = EINVAL;
201			goto out;
202		}
203		KASSERT(dnode->tn_type == VDIR);
204		pnode = dnode->tn_spec.tn_dir.tn_parent;
205		if (pnode == NULL) {
206			error = ENOENT;
207			goto done;
208		}
209
210		error = vcache_get(dvp->v_mount, &pnode, sizeof(pnode), vpp);
211		goto done;
212	} else if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
213		/*
214		 * Lookup of "." case.
215		 */
216		if (lastcn && cnp->cn_nameiop == RENAME) {
217			error = EISDIR;
218			goto out;
219		}
220		vref(dvp);
221		*vpp = dvp;
222		error = 0;
223		goto done;
224	}
225
226	/*
227	 * Other lookup cases: perform directory scan.
228	 */
229	de = tmpfs_dir_lookup(dnode, cnp);
230	if (de == NULL || de->td_node == TMPFS_NODE_WHITEOUT) {
231		/*
232		 * The entry was not found in the directory.  This is valid
233		 * if we are creating or renaming an entry and are working
234		 * on the last component of the path name.
235		 */
236		if (lastcn && (cnp->cn_nameiop == CREATE ||
237		    cnp->cn_nameiop == RENAME)) {
238			error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred);
239			if (error) {
240				goto out;
241			}
242			error = EJUSTRETURN;
243		} else {
244			error = ENOENT;
245		}
246		if (de) {
247			KASSERT(de->td_node == TMPFS_NODE_WHITEOUT);
248			cnp->cn_flags |= ISWHITEOUT;
249		}
250		goto done;
251	}
252
253	tnode = de->td_node;
254
255	/*
256	 * If it is not the last path component and found a non-directory
257	 * or non-link entry (which may itself be pointing to a directory),
258	 * raise an error.
259	 */
260	if (!lastcn && tnode->tn_type != VDIR && tnode->tn_type != VLNK) {
261		error = ENOTDIR;
262		goto out;
263	}
264
265	/* Check the permissions. */
266	if (lastcn && (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
267		error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred);
268		if (error)
269			goto out;
270
271		if ((dnode->tn_mode & S_ISTXT) != 0) {
272			error = kauth_authorize_vnode(cnp->cn_cred,
273			    KAUTH_VNODE_DELETE, tnode->tn_vnode,
274			    dnode->tn_vnode, genfs_can_sticky(dvp, cnp->cn_cred,
275			    dnode->tn_uid, tnode->tn_uid));
276			if (error) {
277				error = EPERM;
278				goto out;
279			}
280		}
281	}
282
283	/* Get a vnode for the matching entry. */
284	error = vcache_get(dvp->v_mount, &tnode, sizeof(tnode), vpp);
285done:
286	/*
287	 * Cache the result, unless request was for creation (as it does
288	 * not improve the performance).
289	 */
290	if (cnp->cn_nameiop != CREATE) {
291		cache_enter(dvp, *vpp, cnp->cn_nameptr, cnp->cn_namelen,
292			    cnp->cn_flags);
293	}
294out:
295	KASSERT(VOP_ISLOCKED(dvp));
296
297	return error;
298}
299
300int
301tmpfs_create(void *v)
302{
303	struct vop_create_v3_args /* {
304		struct vnode		*a_dvp;
305		struct vnode		**a_vpp;
306		struct componentname	*a_cnp;
307		struct vattr		*a_vap;
308	} */ *ap = v;
309	vnode_t *dvp = ap->a_dvp, **vpp = ap->a_vpp;
310	struct componentname *cnp = ap->a_cnp;
311	struct vattr *vap = ap->a_vap;
312
313	KASSERT(VOP_ISLOCKED(dvp));
314	KASSERT(vap->va_type == VREG || vap->va_type == VSOCK);
315	return tmpfs_construct_node(dvp, vpp, vap, cnp, NULL);
316}
317
318int
319tmpfs_mknod(void *v)
320{
321	struct vop_mknod_v3_args /* {
322		struct vnode		*a_dvp;
323		struct vnode		**a_vpp;
324		struct componentname	*a_cnp;
325		struct vattr		*a_vap;
326	} */ *ap = v;
327	vnode_t *dvp = ap->a_dvp, **vpp = ap->a_vpp;
328	struct componentname *cnp = ap->a_cnp;
329	struct vattr *vap = ap->a_vap;
330	enum vtype vt = vap->va_type;
331
332	if (vt != VBLK && vt != VCHR && vt != VFIFO) {
333		*vpp = NULL;
334		return EINVAL;
335	}
336	return tmpfs_construct_node(dvp, vpp, vap, cnp, NULL);
337}
338
339int
340tmpfs_open(void *v)
341{
342	struct vop_open_args /* {
343		struct vnode	*a_vp;
344		int		a_mode;
345		kauth_cred_t	a_cred;
346	} */ *ap = v;
347	vnode_t *vp = ap->a_vp;
348	mode_t mode = ap->a_mode;
349	tmpfs_node_t *node;
350
351	KASSERT(VOP_ISLOCKED(vp));
352
353	node = VP_TO_TMPFS_NODE(vp);
354
355	/* If the file is marked append-only, deny write requests. */
356	if ((node->tn_flags & APPEND) != 0 &&
357	    (mode & (FWRITE | O_APPEND)) == FWRITE) {
358		return EPERM;
359	}
360	return 0;
361}
362
363int
364tmpfs_close(void *v)
365{
366	struct vop_close_args /* {
367		struct vnode	*a_vp;
368		int		a_fflag;
369		kauth_cred_t	a_cred;
370	} */ *ap = v;
371	vnode_t *vp __diagused = ap->a_vp;
372
373	KASSERT(VOP_ISLOCKED(vp));
374	return 0;
375}
376
377int
378tmpfs_access(void *v)
379{
380	struct vop_access_args /* {
381		struct vnode	*a_vp;
382		accmode_t	a_accmode;
383		kauth_cred_t	a_cred;
384	} */ *ap = v;
385	vnode_t *vp = ap->a_vp;
386	accmode_t accmode = ap->a_accmode;
387	kauth_cred_t cred = ap->a_cred;
388	tmpfs_node_t *node = VP_TO_TMPFS_NODE(vp);
389	const bool writing = (accmode & VWRITE) != 0;
390
391	KASSERT(VOP_ISLOCKED(vp));
392
393	/* Possible? */
394	switch (vp->v_type) {
395	case VDIR:
396	case VLNK:
397	case VREG:
398		if (writing && (vp->v_mount->mnt_flag & MNT_RDONLY) != 0) {
399			return EROFS;
400		}
401		break;
402	case VBLK:
403	case VCHR:
404	case VSOCK:
405	case VFIFO:
406		break;
407	default:
408		return EINVAL;
409	}
410	if (writing && (node->tn_flags & IMMUTABLE) != 0) {
411		return EPERM;
412	}
413
414	return kauth_authorize_vnode(cred, KAUTH_ACCESS_ACTION(accmode,
415	    vp->v_type, node->tn_mode), vp, NULL, genfs_can_access(vp, cred,
416	    node->tn_uid, node->tn_gid, node->tn_mode, NULL, accmode));
417}
418
419int
420tmpfs_getattr(void *v)
421{
422	struct vop_getattr_args /* {
423		struct vnode	*a_vp;
424		struct vattr	*a_vap;
425		kauth_cred_t	a_cred;
426	} */ *ap = v;
427	vnode_t *vp = ap->a_vp;
428	struct vattr *vap = ap->a_vap;
429	tmpfs_node_t *node = VP_TO_TMPFS_NODE(vp);
430
431	vattr_null(vap);
432
433	vap->va_type = vp->v_type;
434	vap->va_mode = node->tn_mode;
435	vap->va_nlink = node->tn_links;
436	vap->va_uid = node->tn_uid;
437	vap->va_gid = node->tn_gid;
438	vap->va_fsid = vp->v_mount->mnt_stat.f_fsidx.__fsid_val[0];
439	vap->va_fileid = node->tn_id;
440	vap->va_size = node->tn_size;
441	vap->va_blocksize = PAGE_SIZE;
442	vap->va_gen = TMPFS_NODE_GEN(node);
443	vap->va_flags = node->tn_flags;
444	vap->va_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ?
445	    node->tn_spec.tn_dev.tn_rdev : VNOVAL;
446	vap->va_bytes = round_page(node->tn_size);
447	vap->va_filerev = VNOVAL;
448	vap->va_vaflags = 0;
449	vap->va_spare = VNOVAL; /* XXX */
450
451	mutex_enter(&node->tn_timelock);
452	tmpfs_update_locked(vp, 0);
453	vap->va_atime = node->tn_atime;
454	vap->va_mtime = node->tn_mtime;
455	vap->va_ctime = node->tn_ctime;
456	vap->va_birthtime = node->tn_birthtime;
457	mutex_exit(&node->tn_timelock);
458
459	return 0;
460}
461
462int
463tmpfs_setattr(void *v)
464{
465	struct vop_setattr_args /* {
466		struct vnode	*a_vp;
467		struct vattr	*a_vap;
468		kauth_cred_t	a_cred;
469	} */ *ap = v;
470	vnode_t *vp = ap->a_vp;
471	struct vattr *vap = ap->a_vap;
472	kauth_cred_t cred = ap->a_cred;
473	lwp_t *l = curlwp;
474	int error = 0;
475
476	KASSERT(VOP_ISLOCKED(vp));
477
478	/* Abort if any unsettable attribute is given. */
479	if (vap->va_type != VNON || vap->va_nlink != VNOVAL ||
480	    vap->va_fsid != VNOVAL || vap->va_fileid != VNOVAL ||
481	    vap->va_blocksize != VNOVAL || vap->va_ctime.tv_sec != VNOVAL ||
482	    vap->va_gen != VNOVAL || vap->va_rdev != VNOVAL ||
483	    vap->va_bytes != VNOVAL) {
484		return EINVAL;
485	}
486
487	if (error == 0 && vap->va_flags != VNOVAL)
488		error = tmpfs_chflags(vp, vap->va_flags, cred, l);
489
490	if (error == 0 && vap->va_size != VNOVAL)
491		error = tmpfs_chsize(vp, vap->va_size, cred, l);
492
493	if (error == 0 && (vap->va_uid != VNOVAL || vap->va_gid != VNOVAL))
494		error = tmpfs_chown(vp, vap->va_uid, vap->va_gid, cred, l);
495
496	if (error == 0 && vap->va_mode != VNOVAL)
497		error = tmpfs_chmod(vp, vap->va_mode, cred, l);
498
499	const bool chsometime =
500	    vap->va_atime.tv_sec != VNOVAL ||
501	    vap->va_mtime.tv_sec != VNOVAL ||
502	    vap->va_birthtime.tv_sec != VNOVAL;
503	if (error == 0 && chsometime) {
504		error = tmpfs_chtimes(vp, &vap->va_atime, &vap->va_mtime,
505		    &vap->va_birthtime, vap->va_vaflags, cred, l);
506	}
507	return error;
508}
509
510int
511tmpfs_read(void *v)
512{
513	struct vop_read_args /* {
514		struct vnode *a_vp;
515		struct uio *a_uio;
516		int a_ioflag;
517		kauth_cred_t a_cred;
518	} */ *ap = v;
519	vnode_t *vp = ap->a_vp;
520	struct uio *uio = ap->a_uio;
521	const int ioflag = ap->a_ioflag;
522	tmpfs_node_t *node;
523	struct uvm_object *uobj;
524	int error;
525
526	KASSERT(VOP_ISLOCKED(vp));
527
528	if (vp->v_type == VDIR) {
529		return EISDIR;
530	}
531	if (uio->uio_offset < 0 || vp->v_type != VREG) {
532		return EINVAL;
533	}
534
535	/* Note: reading zero bytes should not update atime. */
536	if (uio->uio_resid == 0) {
537		return 0;
538	}
539
540	node = VP_TO_TMPFS_NODE(vp);
541	uobj = node->tn_spec.tn_reg.tn_aobj;
542	error = 0;
543
544	while (error == 0 && uio->uio_resid > 0) {
545		vsize_t len;
546
547		if (node->tn_size <= uio->uio_offset) {
548			break;
549		}
550		len = MIN(node->tn_size - uio->uio_offset, uio->uio_resid);
551		if (len == 0) {
552			break;
553		}
554		error = ubc_uiomove(uobj, uio, len, IO_ADV_DECODE(ioflag),
555		    UBC_READ | UBC_PARTIALOK | UBC_VNODE_FLAGS(vp));
556	}
557
558	if ((vp->v_mount->mnt_flag & MNT_NOATIME) == 0)
559		tmpfs_update(vp, TMPFS_UPDATE_ATIME);
560
561	return error;
562}
563
564int
565tmpfs_write(void *v)
566{
567	struct vop_write_args /* {
568		struct vnode	*a_vp;
569		struct uio	*a_uio;
570		int		a_ioflag;
571		kauth_cred_t	a_cred;
572	} */ *ap = v;
573	vnode_t *vp = ap->a_vp;
574	struct uio *uio = ap->a_uio;
575	const int ioflag = ap->a_ioflag;
576	tmpfs_node_t *node;
577	struct uvm_object *uobj;
578	off_t oldsize;
579	int error, ubc_flags;
580
581	KASSERT(VOP_ISLOCKED(vp));
582
583	node = VP_TO_TMPFS_NODE(vp);
584	oldsize = node->tn_size;
585
586	if ((vp->v_mount->mnt_flag & MNT_RDONLY) != 0) {
587		error = EROFS;
588		goto out;
589	}
590
591	if (uio->uio_offset < 0 || vp->v_type != VREG) {
592		error = EINVAL;
593		goto out;
594	}
595	if (uio->uio_resid == 0) {
596		error = 0;
597		goto out;
598	}
599	if (ioflag & IO_APPEND) {
600		uio->uio_offset = node->tn_size;
601	}
602
603	if (uio->uio_offset + uio->uio_resid > node->tn_size) {
604		error = tmpfs_reg_resize(vp, uio->uio_offset + uio->uio_resid);
605		if (error)
606			goto out;
607	}
608
609	/*
610	 * If we're extending the file and have data to write that would
611	 * not leave an un-zeroed hole, we can avoid fault processing and
612	 * zeroing of pages on allocation.
613	 *
614	 * Don't do this if the file is mapped and we need to touch an
615	 * existing page, because writing a mapping of the file into itself
616	 * could cause a deadlock on PG_BUSY.
617	 *
618	 * New pages will not become visible until finished here (because
619	 * of PG_BUSY and the vnode lock).
620	 */
621	ubc_flags = UBC_WRITE | UBC_VNODE_FLAGS(vp);
622#if 0
623	/*
624	 * XXX disable use of UBC_FAULTBUSY for now, this check is insufficient
625	 * because it does not zero uninitialized parts of pages in all of
626	 * the cases where zeroing is needed.
627	 */
628	if (uio->uio_offset >= oldsize &&
629	    ((uio->uio_offset & (PAGE_SIZE - 1)) == 0 ||
630	    ((vp->v_vflag & VV_MAPPED) == 0 &&
631	    trunc_page(uio->uio_offset) == trunc_page(oldsize)))) {
632		ubc_flags |= UBC_FAULTBUSY;
633	}
634#endif
635
636	uobj = node->tn_spec.tn_reg.tn_aobj;
637	error = 0;
638	while (error == 0 && uio->uio_resid > 0) {
639		vsize_t len;
640
641		len = MIN(node->tn_size - uio->uio_offset, uio->uio_resid);
642		if (len == 0) {
643			break;
644		}
645		error = ubc_uiomove(uobj, uio, len, IO_ADV_DECODE(ioflag),
646		    ubc_flags);
647	}
648	if (error) {
649		(void)tmpfs_reg_resize(vp, oldsize);
650	}
651
652	tmpfs_update(vp, TMPFS_UPDATE_MTIME | TMPFS_UPDATE_CTIME);
653out:
654	if (error) {
655		KASSERT(oldsize == node->tn_size);
656	} else {
657		KASSERT(uio->uio_resid == 0);
658	}
659	return error;
660}
661
662int
663tmpfs_fsync(void *v)
664{
665	struct vop_fsync_args /* {
666		struct vnode *a_vp;
667		kauth_cred_t a_cred;
668		int a_flags;
669		off_t a_offlo;
670		off_t a_offhi;
671		struct lwp *a_l;
672	} */ *ap = v;
673	vnode_t *vp __diagused = ap->a_vp;
674
675	/* Nothing to do.  Should be up to date. */
676	KASSERT(VOP_ISLOCKED(vp));
677	return 0;
678}
679
680/*
681 * tmpfs_remove: unlink a file.
682 *
683 * => Both directory (dvp) and file (vp) are locked.
684 * => We unlock and drop the reference on both.
685 */
686int
687tmpfs_remove(void *v)
688{
689	struct vop_remove_v3_args /* {
690		struct vnode *a_dvp;
691		struct vnode *a_vp;
692		struct componentname *a_cnp;
693		nlink_t ctx_vp_new_nlink;
694	} */ *ap = v;
695	vnode_t *dvp = ap->a_dvp, *vp = ap->a_vp;
696	tmpfs_node_t *dnode, *node;
697	tmpfs_dirent_t *de;
698	int error, tflags;
699
700	KASSERT(VOP_ISLOCKED(dvp));
701	KASSERT(VOP_ISLOCKED(vp));
702
703	if (vp->v_type == VDIR) {
704		error = EPERM;
705		goto out;
706	}
707	dnode = VP_TO_TMPFS_DIR(dvp);
708	node = VP_TO_TMPFS_NODE(vp);
709
710	/*
711	 * Files marked as immutable or append-only cannot be deleted.
712	 * Likewise, files residing on directories marked as append-only
713	 * cannot be deleted.
714	 */
715	if (node->tn_flags & (IMMUTABLE | APPEND)) {
716		error = EPERM;
717		goto out;
718	}
719	if (dnode->tn_flags & APPEND) {
720		error = EPERM;
721		goto out;
722	}
723
724	/* Lookup the directory entry (check the cached hint first). */
725	de = tmpfs_dir_cached(node);
726	if (de == NULL) {
727		struct componentname *cnp = ap->a_cnp;
728		de = tmpfs_dir_lookup(dnode, cnp);
729	}
730	KASSERT(de && de->td_node == node);
731
732	/*
733	 * Remove the entry from the directory (drops the link count) and
734	 * destroy it or replace with a whiteout.
735	 *
736	 * Note: the inode referred by it will not be destroyed until the
737	 * vnode is reclaimed/recycled.
738	 */
739
740	tmpfs_dir_detach(dnode, de);
741
742	if (ap->a_cnp->cn_flags & DOWHITEOUT)
743		tmpfs_dir_attach(dnode, de, TMPFS_NODE_WHITEOUT);
744	else
745		tmpfs_free_dirent(VFS_TO_TMPFS(vp->v_mount), de);
746
747	tflags = TMPFS_UPDATE_MTIME | TMPFS_UPDATE_CTIME;
748	if (node->tn_links > 0) {
749		/* We removed a hard link. */
750		tflags |= TMPFS_UPDATE_CTIME;
751	}
752	ap->ctx_vp_new_nlink = node->tn_links;
753	tmpfs_update(dvp, tflags);
754	error = 0;
755out:
756	/* Drop the reference and unlock the node. */
757	if (dvp == vp) {
758		vrele(vp);
759	} else {
760		vput(vp);
761	}
762	return error;
763}
764
765/*
766 * tmpfs_link: create a hard link.
767 */
768int
769tmpfs_link(void *v)
770{
771	struct vop_link_v2_args /* {
772		struct vnode *a_dvp;
773		struct vnode *a_vp;
774		struct componentname *a_cnp;
775	} */ *ap = v;
776	vnode_t *dvp = ap->a_dvp;
777	vnode_t *vp = ap->a_vp;
778	struct componentname *cnp = ap->a_cnp;
779	tmpfs_node_t *dnode, *node;
780	tmpfs_dirent_t *de;
781	int error;
782
783	KASSERT(dvp != vp);
784	KASSERT(VOP_ISLOCKED(dvp));
785	KASSERT(vp->v_type != VDIR);
786	KASSERT(dvp->v_mount == vp->v_mount);
787
788	dnode = VP_TO_TMPFS_DIR(dvp);
789	node = VP_TO_TMPFS_NODE(vp);
790
791	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
792
793	/* Check for maximum number of links limit. */
794	if (node->tn_links == LINK_MAX) {
795		error = EMLINK;
796		goto out;
797	}
798	KASSERT(node->tn_links < LINK_MAX);
799
800	/* We cannot create links of files marked immutable or append-only. */
801	if (node->tn_flags & (IMMUTABLE | APPEND)) {
802		error = EPERM;
803		goto out;
804	}
805
806	error = kauth_authorize_vnode(cnp->cn_cred, KAUTH_VNODE_ADD_LINK, vp,
807	    dvp, 0);
808	if (error)
809		goto out;
810
811	/* Allocate a new directory entry to represent the inode. */
812	error = tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount),
813	    cnp->cn_nameptr, cnp->cn_namelen, &de);
814	if (error) {
815		goto out;
816	}
817
818	/*
819	 * Insert the entry into the directory.
820	 * It will increase the inode link count.
821	 */
822	tmpfs_dir_attach(dnode, de, node);
823	tmpfs_update(dvp, TMPFS_UPDATE_MTIME | TMPFS_UPDATE_CTIME);
824
825	/* Update the timestamps. */
826	tmpfs_update(vp, TMPFS_UPDATE_CTIME);
827	error = 0;
828out:
829	VOP_UNLOCK(vp);
830	return error;
831}
832
833int
834tmpfs_mkdir(void *v)
835{
836	struct vop_mkdir_v3_args /* {
837		struct vnode		*a_dvp;
838		struct vnode		**a_vpp;
839		struct componentname	*a_cnp;
840		struct vattr		*a_vap;
841	} */ *ap = v;
842	vnode_t *dvp = ap->a_dvp;
843	vnode_t **vpp = ap->a_vpp;
844	struct componentname *cnp = ap->a_cnp;
845	struct vattr *vap = ap->a_vap;
846
847	KASSERT(vap->va_type == VDIR);
848	return tmpfs_construct_node(dvp, vpp, vap, cnp, NULL);
849}
850
851int
852tmpfs_rmdir(void *v)
853{
854	struct vop_rmdir_v2_args /* {
855		struct vnode		*a_dvp;
856		struct vnode		*a_vp;
857		struct componentname	*a_cnp;
858	} */ *ap = v;
859	vnode_t *dvp = ap->a_dvp;
860	vnode_t *vp = ap->a_vp;
861	tmpfs_mount_t *tmp = VFS_TO_TMPFS(dvp->v_mount);
862	tmpfs_node_t *dnode = VP_TO_TMPFS_DIR(dvp);
863	tmpfs_node_t *node = VP_TO_TMPFS_DIR(vp);
864	tmpfs_dirent_t *de;
865	int error = 0;
866
867	KASSERT(VOP_ISLOCKED(dvp));
868	KASSERT(VOP_ISLOCKED(vp));
869
870	/*
871	 * Directories with more than two entries ('.' and '..') cannot be
872	 * removed.  There may be whiteout entries, which we will destroy.
873	 */
874	if (node->tn_size > 0) {
875		/*
876		 * If never had whiteout entries, the directory is certainly
877		 * not empty.  Otherwise, scan for any non-whiteout entry.
878		 */
879		if ((node->tn_gen & TMPFS_WHITEOUT_BIT) == 0) {
880			error = ENOTEMPTY;
881			goto out;
882		}
883		TAILQ_FOREACH(de, &node->tn_spec.tn_dir.tn_dir, td_entries) {
884			if (de->td_node != TMPFS_NODE_WHITEOUT) {
885				error = ENOTEMPTY;
886				goto out;
887			}
888		}
889		KASSERT(error == 0);
890	}
891
892	KASSERT(node->tn_spec.tn_dir.tn_parent == dnode);
893
894	/* Lookup the directory entry (check the cached hint first). */
895	de = tmpfs_dir_cached(node);
896	if (de == NULL) {
897		struct componentname *cnp = ap->a_cnp;
898		de = tmpfs_dir_lookup(dnode, cnp);
899	}
900	KASSERT(de && de->td_node == node);
901
902	/* Check flags to see if we are allowed to remove the directory. */
903	if (dnode->tn_flags & APPEND || node->tn_flags & (IMMUTABLE | APPEND)) {
904		error = EPERM;
905		goto out;
906	}
907
908	/* Decrement the link count for the virtual '.' entry. */
909	node->tn_links--;
910
911	/* Detach the directory entry from the directory. */
912	tmpfs_dir_detach(dnode, de);
913
914	/* Purge the cache for parent. */
915	cache_purge(dvp);
916
917	/*
918	 * Destroy the directory entry or replace it with a whiteout.
919	 *
920	 * Note: the inode referred by it will not be destroyed until the
921	 * vnode is reclaimed.
922	 */
923	if (ap->a_cnp->cn_flags & DOWHITEOUT)
924		tmpfs_dir_attach(dnode, de, TMPFS_NODE_WHITEOUT);
925	else
926		tmpfs_free_dirent(tmp, de);
927
928	/* Destroy the whiteout entries from the node. */
929	while ((de = TAILQ_FIRST(&node->tn_spec.tn_dir.tn_dir)) != NULL) {
930		KASSERT(de->td_node == TMPFS_NODE_WHITEOUT);
931		tmpfs_dir_detach(node, de);
932		tmpfs_free_dirent(tmp, de);
933	}
934	tmpfs_update(dvp, TMPFS_UPDATE_MTIME | TMPFS_UPDATE_CTIME);
935
936	KASSERT(node->tn_size == 0);
937	KASSERT(node->tn_links == 0);
938out:
939	/* Release the node. */
940	KASSERT(dvp != vp);
941	vput(vp);
942	return error;
943}
944
945int
946tmpfs_symlink(void *v)
947{
948	struct vop_symlink_v3_args /* {
949		struct vnode		*a_dvp;
950		struct vnode		**a_vpp;
951		struct componentname	*a_cnp;
952		struct vattr		*a_vap;
953		char			*a_target;
954	} */ *ap = v;
955	vnode_t *dvp = ap->a_dvp;
956	vnode_t **vpp = ap->a_vpp;
957	struct componentname *cnp = ap->a_cnp;
958	struct vattr *vap = ap->a_vap;
959	char *target = ap->a_target;
960
961	KASSERT(vap->va_type == VLNK);
962	return tmpfs_construct_node(dvp, vpp, vap, cnp, target);
963}
964
965int
966tmpfs_readdir(void *v)
967{
968	struct vop_readdir_args /* {
969		struct vnode	*a_vp;
970		struct uio	*a_uio;
971		kauth_cred_t	a_cred;
972		int		*a_eofflag;
973		off_t		**a_cookies;
974		int		*ncookies;
975	} */ *ap = v;
976	vnode_t *vp = ap->a_vp;
977	struct uio *uio = ap->a_uio;
978	int *eofflag = ap->a_eofflag;
979	off_t **cookies = ap->a_cookies;
980	int *ncookies = ap->a_ncookies;
981	off_t startoff, cnt;
982	tmpfs_node_t *node;
983	int error;
984
985	KASSERT(VOP_ISLOCKED(vp));
986
987	/* This operation only makes sense on directory nodes. */
988	if (vp->v_type != VDIR) {
989		return ENOTDIR;
990	}
991	node = VP_TO_TMPFS_DIR(vp);
992	startoff = uio->uio_offset;
993	cnt = 0;
994
995	/*
996	 * Retrieve the directory entries, unless it is being destroyed.
997	 */
998	if (node->tn_links) {
999		error = tmpfs_dir_getdents(node, uio, &cnt);
1000	} else {
1001		error = 0;
1002	}
1003
1004	if (eofflag != NULL) {
1005		*eofflag = !error && uio->uio_offset == TMPFS_DIRSEQ_EOF;
1006	}
1007	if (error || cookies == NULL || ncookies == NULL) {
1008		return error;
1009	}
1010
1011	/* Update NFS-related variables, if any. */
1012	tmpfs_dirent_t *de = NULL;
1013	off_t i, off = startoff;
1014
1015	*cookies = malloc(cnt * sizeof(off_t), M_TEMP, M_WAITOK);
1016	*ncookies = cnt;
1017
1018	for (i = 0; i < cnt; i++) {
1019		KASSERT(off != TMPFS_DIRSEQ_EOF);
1020		if (off != TMPFS_DIRSEQ_DOT) {
1021			if (off == TMPFS_DIRSEQ_DOTDOT) {
1022				de = TAILQ_FIRST(&node->tn_spec.tn_dir.tn_dir);
1023			} else if (de != NULL) {
1024				de = TAILQ_NEXT(de, td_entries);
1025			} else {
1026				de = tmpfs_dir_lookupbyseq(node, off);
1027				KASSERT(de != NULL);
1028				de = TAILQ_NEXT(de, td_entries);
1029			}
1030			if (de == NULL) {
1031				off = TMPFS_DIRSEQ_EOF;
1032			} else {
1033				off = tmpfs_dir_getseq(node, de);
1034			}
1035		} else {
1036			off = TMPFS_DIRSEQ_DOTDOT;
1037		}
1038		(*cookies)[i] = off;
1039	}
1040	KASSERT(uio->uio_offset == off);
1041	return error;
1042}
1043
1044int
1045tmpfs_readlink(void *v)
1046{
1047	struct vop_readlink_args /* {
1048		struct vnode	*a_vp;
1049		struct uio	*a_uio;
1050		kauth_cred_t	a_cred;
1051	} */ *ap = v;
1052	vnode_t *vp = ap->a_vp;
1053	struct uio *uio = ap->a_uio;
1054	tmpfs_node_t *node = VP_TO_TMPFS_NODE(vp);
1055	int error;
1056
1057	KASSERT(VOP_ISLOCKED(vp));
1058	KASSERT(uio->uio_offset == 0);
1059	KASSERT(vp->v_type == VLNK);
1060
1061	/* Note: readlink(2) returns the path without NUL terminator. */
1062	if (node->tn_size > 0) {
1063		error = uiomove(node->tn_spec.tn_lnk.tn_link,
1064		    MIN(node->tn_size, uio->uio_resid), uio);
1065	} else {
1066		error = 0;
1067	}
1068	tmpfs_update(vp, TMPFS_UPDATE_ATIME);
1069
1070	return error;
1071}
1072
1073int
1074tmpfs_inactive(void *v)
1075{
1076	struct vop_inactive_v2_args /* {
1077		struct vnode *a_vp;
1078		bool *a_recycle;
1079	} */ *ap = v;
1080	vnode_t *vp = ap->a_vp;
1081	tmpfs_node_t *node;
1082	int error = 0;
1083
1084	KASSERT(VOP_ISLOCKED(vp));
1085
1086	node = VP_TO_TMPFS_NODE(vp);
1087	if (node->tn_links == 0) {
1088		/*
1089		 * Mark node as dead by setting its generation to zero.
1090		 */
1091		atomic_and_32(&node->tn_gen, ~TMPFS_NODE_GEN_MASK);
1092
1093		/*
1094		 * If the file has been deleted, truncate it, otherwise VFS
1095		 * will quite rightly try to write back dirty data, which in
1096		 * the case of tmpfs/UAO means needless page deactivations.
1097		 */
1098		if (vp->v_type == VREG) {
1099			error = tmpfs_reg_resize(vp, 0);
1100		}
1101		*ap->a_recycle = true;
1102	} else {
1103		tmpfs_update(vp, 0);
1104		*ap->a_recycle = false;
1105	}
1106
1107	return error;
1108}
1109
1110int
1111tmpfs_reclaim(void *v)
1112{
1113	struct vop_reclaim_v2_args /* {
1114		struct vnode *a_vp;
1115	} */ *ap = v;
1116	vnode_t *vp = ap->a_vp;
1117	tmpfs_mount_t *tmp = VFS_TO_TMPFS(vp->v_mount);
1118	tmpfs_node_t *node = VP_TO_TMPFS_NODE(vp);
1119
1120	/* Unlock vnode.  We still have exclusive access to it. */
1121	VOP_UNLOCK(vp);
1122
1123	/* Disassociate inode from vnode. */
1124	node->tn_vnode = NULL;
1125	vp->v_data = NULL;
1126
1127	/* If inode is not referenced, i.e. no links, then destroy it. */
1128	if (node->tn_links == 0)
1129		tmpfs_free_node(tmp, node);
1130	return 0;
1131}
1132
1133int
1134tmpfs_pathconf(void *v)
1135{
1136	struct vop_pathconf_args /* {
1137		struct vnode	*a_vp;
1138		int		a_name;
1139		register_t	*a_retval;
1140	} */ *ap = v;
1141	register_t *retval = ap->a_retval;
1142
1143	switch (ap->a_name) {
1144	case _PC_LINK_MAX:
1145		*retval = LINK_MAX;
1146		return 0;
1147	case _PC_NAME_MAX:
1148		*retval = TMPFS_MAXNAMLEN;
1149		return 0;
1150	case _PC_PATH_MAX:
1151		*retval = PATH_MAX;
1152		return 0;
1153	case _PC_PIPE_BUF:
1154		*retval = PIPE_BUF;
1155		return 0;
1156	case _PC_CHOWN_RESTRICTED:
1157		*retval = 1;
1158		return 0;
1159	case _PC_NO_TRUNC:
1160		*retval = 1;
1161		return 0;
1162	case _PC_SYNC_IO:
1163		*retval = 1;
1164		return 0;
1165	case _PC_FILESIZEBITS:
1166		*retval = sizeof(off_t) * CHAR_BIT;
1167		return 0;
1168	default:
1169		return genfs_pathconf(ap);
1170	}
1171}
1172
1173int
1174tmpfs_advlock(void *v)
1175{
1176	struct vop_advlock_args /* {
1177		struct vnode	*a_vp;
1178		void *		a_id;
1179		int		a_op;
1180		struct flock	*a_fl;
1181		int		a_flags;
1182	} */ *ap = v;
1183	vnode_t *vp = ap->a_vp;
1184	tmpfs_node_t *node = VP_TO_TMPFS_NODE(vp);
1185
1186	return lf_advlock(v, &node->tn_lockf, node->tn_size);
1187}
1188
1189int
1190tmpfs_getpages(void *v)
1191{
1192	struct vop_getpages_args /* {
1193		struct vnode *a_vp;
1194		voff_t a_offset;
1195		struct vm_page **a_m;
1196		int *a_count;
1197		int a_centeridx;
1198		vm_prot_t a_access_type;
1199		int a_advice;
1200		int a_flags;
1201	} */ * const ap = v;
1202	vnode_t *vp = ap->a_vp;
1203	const voff_t offset = ap->a_offset;
1204	struct vm_page **pgs = ap->a_m;
1205	const int centeridx = ap->a_centeridx;
1206	const vm_prot_t access_type = ap->a_access_type;
1207	const int advice = ap->a_advice;
1208	const int flags = ap->a_flags;
1209	int error, iflag, npages = *ap->a_count;
1210	tmpfs_node_t *node;
1211	struct uvm_object *uobj;
1212
1213	KASSERT(vp->v_type == VREG);
1214	KASSERT(rw_lock_held(vp->v_uobj.vmobjlock));
1215
1216	/*
1217	 * Currently, PGO_PASTEOF is not supported.
1218	 */
1219	if (vp->v_size <= offset + (centeridx << PAGE_SHIFT)) {
1220		if ((flags & PGO_LOCKED) == 0)
1221			rw_exit(vp->v_uobj.vmobjlock);
1222		return EINVAL;
1223	}
1224
1225	if (vp->v_size < offset + (npages << PAGE_SHIFT)) {
1226		npages = (round_page(vp->v_size) - offset) >> PAGE_SHIFT;
1227	}
1228
1229	/*
1230	 * Check for reclaimed vnode.  v_interlock is not held here, but
1231	 * VI_DEADCHECK is set with vmobjlock held.
1232	 */
1233	iflag = atomic_load_relaxed(&vp->v_iflag);
1234	if (__predict_false((iflag & VI_DEADCHECK) != 0)) {
1235		mutex_enter(vp->v_interlock);
1236		error = vdead_check(vp, VDEAD_NOWAIT);
1237		mutex_exit(vp->v_interlock);
1238		if (error) {
1239			if ((flags & PGO_LOCKED) == 0)
1240				rw_exit(vp->v_uobj.vmobjlock);
1241			return error;
1242		}
1243	}
1244
1245	node = VP_TO_TMPFS_NODE(vp);
1246	uobj = node->tn_spec.tn_reg.tn_aobj;
1247
1248	/*
1249	 * Update timestamp lazily.  The update will be made real when
1250	 * a synchronous update is next made -- or by tmpfs_getattr,
1251	 * tmpfs_putpages, and tmpfs_inactive.
1252	 */
1253	if ((flags & PGO_NOTIMESTAMP) == 0) {
1254		u_int tflags = 0;
1255
1256		if ((vp->v_mount->mnt_flag & MNT_NOATIME) == 0)
1257			tflags |= TMPFS_UPDATE_ATIME;
1258
1259		if ((access_type & VM_PROT_WRITE) != 0) {
1260			tflags |= TMPFS_UPDATE_MTIME;
1261			if (vp->v_mount->mnt_flag & MNT_RELATIME)
1262				tflags |= TMPFS_UPDATE_ATIME;
1263		}
1264		tmpfs_update_lazily(vp, tflags);
1265	}
1266
1267	/* Invoke the pager.  The vnode vmobjlock is shared with the UAO. */
1268	KASSERT(vp->v_uobj.vmobjlock == uobj->vmobjlock);
1269	error = (*uobj->pgops->pgo_get)(uobj, offset, pgs, &npages, centeridx,
1270	    access_type, advice, flags);
1271#if defined(DEBUG)
1272	if (!error && pgs) {
1273		KASSERT(pgs[centeridx] != NULL);
1274	}
1275#endif
1276	return error;
1277}
1278
1279int
1280tmpfs_putpages(void *v)
1281{
1282	struct vop_putpages_args /* {
1283		struct vnode *a_vp;
1284		voff_t a_offlo;
1285		voff_t a_offhi;
1286		int a_flags;
1287	} */ * const ap = v;
1288	vnode_t *vp = ap->a_vp;
1289	const voff_t offlo = ap->a_offlo;
1290	const voff_t offhi = ap->a_offhi;
1291	const int flags = ap->a_flags;
1292	tmpfs_node_t *node;
1293	struct uvm_object *uobj;
1294	int error;
1295
1296	KASSERT(rw_write_held(vp->v_uobj.vmobjlock));
1297
1298	if (vp->v_type != VREG) {
1299		rw_exit(vp->v_uobj.vmobjlock);
1300		return 0;
1301	}
1302
1303	node = VP_TO_TMPFS_NODE(vp);
1304	uobj = node->tn_spec.tn_reg.tn_aobj;
1305
1306	KASSERT(vp->v_uobj.vmobjlock == uobj->vmobjlock);
1307	error = (*uobj->pgops->pgo_put)(uobj, offlo, offhi, flags);
1308
1309	/* XXX mtime */
1310
1311	/* Process deferred updates. */
1312	tmpfs_update(vp, 0);
1313	return error;
1314}
1315
1316int
1317tmpfs_whiteout(void *v)
1318{
1319	struct vop_whiteout_args /* {
1320		struct vnode		*a_dvp;
1321		struct componentname	*a_cnp;
1322		int			a_flags;
1323	} */ *ap = v;
1324	vnode_t *dvp = ap->a_dvp;
1325	struct componentname *cnp = ap->a_cnp;
1326	const int flags = ap->a_flags;
1327	tmpfs_mount_t *tmp = VFS_TO_TMPFS(dvp->v_mount);
1328	tmpfs_node_t *dnode = VP_TO_TMPFS_DIR(dvp);
1329	tmpfs_dirent_t *de;
1330	int error;
1331
1332	switch (flags) {
1333	case LOOKUP:
1334		break;
1335	case CREATE:
1336		error = tmpfs_alloc_dirent(tmp, cnp->cn_nameptr,
1337		    cnp->cn_namelen, &de);
1338		if (error)
1339			return error;
1340		tmpfs_dir_attach(dnode, de, TMPFS_NODE_WHITEOUT);
1341		break;
1342	case DELETE:
1343		cnp->cn_flags &= ~DOWHITEOUT; /* when in doubt, cargo cult */
1344		de = tmpfs_dir_lookup(dnode, cnp);
1345		if (de == NULL)
1346			return ENOENT;
1347		tmpfs_dir_detach(dnode, de);
1348		tmpfs_free_dirent(tmp, de);
1349		break;
1350	}
1351	tmpfs_update(dvp, TMPFS_UPDATE_MTIME | TMPFS_UPDATE_CTIME);
1352	return 0;
1353}
1354
1355int
1356tmpfs_print(void *v)
1357{
1358	struct vop_print_args /* {
1359		struct vnode	*a_vp;
1360	} */ *ap = v;
1361	vnode_t *vp = ap->a_vp;
1362	tmpfs_node_t *node = VP_TO_TMPFS_NODE(vp);
1363
1364	printf("tag VT_TMPFS, tmpfs_node %p, flags 0x%x, links %d\n"
1365	    "\tmode 0%o, owner %d, group %d, size %" PRIdMAX,
1366	    node, node->tn_flags, node->tn_links, node->tn_mode, node->tn_uid,
1367	    node->tn_gid, (uintmax_t)node->tn_size);
1368	if (vp->v_type == VFIFO) {
1369		VOCALL(fifo_vnodeop_p, VOFFSET(vop_print), v);
1370	}
1371	printf("\n");
1372	return 0;
1373}
1374