1/*	$NetBSD: tmpfs_vnops.c,v 1.39 2007/07/23 15:41:01 jmmv Exp $	*/
2
3/*-
4 * SPDX-License-Identifier: BSD-2-Clause-NetBSD
5 *
6 * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc.
7 * All rights reserved.
8 *
9 * This code is derived from software contributed to The NetBSD Foundation
10 * by Julio M. Merino Vidal, developed as part of Google's Summer of Code
11 * 2005 program.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32 * POSSIBILITY OF SUCH DAMAGE.
33 */
34
35/*
36 * tmpfs vnode interface.
37 */
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD$");
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/dirent.h>
44#include <sys/fcntl.h>
45#include <sys/limits.h>
46#include <sys/lockf.h>
47#include <sys/lock.h>
48#include <sys/mount.h>
49#include <sys/namei.h>
50#include <sys/priv.h>
51#include <sys/proc.h>
52#include <sys/rwlock.h>
53#include <sys/sched.h>
54#include <sys/stat.h>
55#include <sys/sysctl.h>
56#include <sys/unistd.h>
57#include <sys/vnode.h>
58
59#include <vm/vm.h>
60#include <vm/vm_param.h>
61#include <vm/vm_object.h>
62
63#include <fs/tmpfs/tmpfs_vnops.h>
64#include <fs/tmpfs/tmpfs.h>
65
66SYSCTL_DECL(_vfs_tmpfs);
67
68static volatile int tmpfs_rename_restarts;
69SYSCTL_INT(_vfs_tmpfs, OID_AUTO, rename_restarts, CTLFLAG_RD,
70    __DEVOLATILE(int *, &tmpfs_rename_restarts), 0,
71    "Times rename had to restart due to lock contention");
72
73static int
74tmpfs_vn_get_ino_alloc(struct mount *mp, void *arg, int lkflags,
75    struct vnode **rvp)
76{
77
78	return (tmpfs_alloc_vp(mp, arg, lkflags, rvp));
79}
80
81static int
82tmpfs_lookup1(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
83{
84	struct tmpfs_dirent *de;
85	struct tmpfs_node *dnode, *pnode;
86	struct tmpfs_mount *tm;
87	int error;
88
89	/* Caller assumes responsibility for ensuring access (VEXEC). */
90	dnode = VP_TO_TMPFS_DIR(dvp);
91	*vpp = NULLVP;
92
93	/* We cannot be requesting the parent directory of the root node. */
94	MPASS(IMPLIES(dnode->tn_type == VDIR &&
95	    dnode->tn_dir.tn_parent == dnode,
96	    !(cnp->cn_flags & ISDOTDOT)));
97
98	TMPFS_ASSERT_LOCKED(dnode);
99	if (dnode->tn_dir.tn_parent == NULL) {
100		error = ENOENT;
101		goto out;
102	}
103	if (cnp->cn_flags & ISDOTDOT) {
104		tm = VFS_TO_TMPFS(dvp->v_mount);
105		pnode = dnode->tn_dir.tn_parent;
106		tmpfs_ref_node(pnode);
107		error = vn_vget_ino_gen(dvp, tmpfs_vn_get_ino_alloc,
108		    pnode, cnp->cn_lkflags, vpp);
109		tmpfs_free_node(tm, pnode);
110		if (error != 0)
111			goto out;
112	} else if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
113		VREF(dvp);
114		*vpp = dvp;
115		error = 0;
116	} else {
117		de = tmpfs_dir_lookup(dnode, NULL, cnp);
118		if (de != NULL && de->td_node == NULL)
119			cnp->cn_flags |= ISWHITEOUT;
120		if (de == NULL || de->td_node == NULL) {
121			/*
122			 * The entry was not found in the directory.
123			 * This is OK if we are creating or renaming an
124			 * entry and are working on the last component of
125			 * the path name.
126			 */
127			if ((cnp->cn_flags & ISLASTCN) &&
128			    (cnp->cn_nameiop == CREATE || \
129			    cnp->cn_nameiop == RENAME ||
130			    (cnp->cn_nameiop == DELETE &&
131			    cnp->cn_flags & DOWHITEOUT &&
132			    cnp->cn_flags & ISWHITEOUT))) {
133				error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred,
134				    cnp->cn_thread);
135				if (error != 0)
136					goto out;
137
138				/*
139				 * Keep the component name in the buffer for
140				 * future uses.
141				 */
142				cnp->cn_flags |= SAVENAME;
143
144				error = EJUSTRETURN;
145			} else
146				error = ENOENT;
147		} else {
148			struct tmpfs_node *tnode;
149
150			/*
151			 * The entry was found, so get its associated
152			 * tmpfs_node.
153			 */
154			tnode = de->td_node;
155
156			/*
157			 * If we are not at the last path component and
158			 * found a non-directory or non-link entry (which
159			 * may itself be pointing to a directory), raise
160			 * an error.
161			 */
162			if ((tnode->tn_type != VDIR &&
163			    tnode->tn_type != VLNK) &&
164			    !(cnp->cn_flags & ISLASTCN)) {
165				error = ENOTDIR;
166				goto out;
167			}
168
169			/*
170			 * If we are deleting or renaming the entry, keep
171			 * track of its tmpfs_dirent so that it can be
172			 * easily deleted later.
173			 */
174			if ((cnp->cn_flags & ISLASTCN) &&
175			    (cnp->cn_nameiop == DELETE ||
176			    cnp->cn_nameiop == RENAME)) {
177				error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred,
178				    cnp->cn_thread);
179				if (error != 0)
180					goto out;
181
182				/* Allocate a new vnode on the matching entry. */
183				error = tmpfs_alloc_vp(dvp->v_mount, tnode,
184				    cnp->cn_lkflags, vpp);
185				if (error != 0)
186					goto out;
187
188				if ((dnode->tn_mode & S_ISTXT) &&
189				  VOP_ACCESS(dvp, VADMIN, cnp->cn_cred,
190				  cnp->cn_thread) && VOP_ACCESS(*vpp, VADMIN,
191				  cnp->cn_cred, cnp->cn_thread)) {
192					error = EPERM;
193					vput(*vpp);
194					*vpp = NULL;
195					goto out;
196				}
197				cnp->cn_flags |= SAVENAME;
198			} else {
199				error = tmpfs_alloc_vp(dvp->v_mount, tnode,
200				    cnp->cn_lkflags, vpp);
201				if (error != 0)
202					goto out;
203			}
204		}
205	}
206
207	/*
208	 * Store the result of this lookup in the cache.  Avoid this if the
209	 * request was for creation, as it does not improve timings on
210	 * emprical tests.
211	 */
212	if ((cnp->cn_flags & MAKEENTRY) != 0 && tmpfs_use_nc(dvp))
213		cache_enter(dvp, *vpp, cnp);
214
215out:
216	/*
217	 * If there were no errors, *vpp cannot be null and it must be
218	 * locked.
219	 */
220	MPASS(IFF(error == 0, *vpp != NULLVP && VOP_ISLOCKED(*vpp)));
221
222	return (error);
223}
224
225static int
226tmpfs_cached_lookup(struct vop_cachedlookup_args *v)
227{
228
229	return (tmpfs_lookup1(v->a_dvp, v->a_vpp, v->a_cnp));
230}
231
232static int
233tmpfs_lookup(struct vop_lookup_args *v)
234{
235	struct vnode *dvp = v->a_dvp;
236	struct vnode **vpp = v->a_vpp;
237	struct componentname *cnp = v->a_cnp;
238	int error;
239
240	/* Check accessibility of requested node as a first step. */
241	error = vn_dir_check_exec(dvp, cnp);
242	if (error != 0)
243		return (error);
244
245	return (tmpfs_lookup1(dvp, vpp, cnp));
246}
247
248static int
249tmpfs_create(struct vop_create_args *v)
250{
251	struct vnode *dvp = v->a_dvp;
252	struct vnode **vpp = v->a_vpp;
253	struct componentname *cnp = v->a_cnp;
254	struct vattr *vap = v->a_vap;
255	int error;
256
257	MPASS(vap->va_type == VREG || vap->va_type == VSOCK);
258
259	error = tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
260	if (error == 0 && (cnp->cn_flags & MAKEENTRY) != 0 && tmpfs_use_nc(dvp))
261		cache_enter(dvp, *vpp, cnp);
262	return (error);
263}
264
265static int
266tmpfs_mknod(struct vop_mknod_args *v)
267{
268	struct vnode *dvp = v->a_dvp;
269	struct vnode **vpp = v->a_vpp;
270	struct componentname *cnp = v->a_cnp;
271	struct vattr *vap = v->a_vap;
272
273	if (vap->va_type != VBLK && vap->va_type != VCHR &&
274	    vap->va_type != VFIFO)
275		return EINVAL;
276
277	return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
278}
279
280static int
281tmpfs_open(struct vop_open_args *v)
282{
283	struct vnode *vp = v->a_vp;
284	int mode = v->a_mode;
285
286	int error;
287	struct tmpfs_node *node;
288
289	MPASS(VOP_ISLOCKED(vp));
290
291	node = VP_TO_TMPFS_NODE(vp);
292
293	/* The file is still active but all its names have been removed
294	 * (e.g. by a "rmdir $(pwd)").  It cannot be opened any more as
295	 * it is about to die. */
296	if (node->tn_links < 1)
297		return (ENOENT);
298
299	/* If the file is marked append-only, deny write requests. */
300	if (node->tn_flags & APPEND && (mode & (FWRITE | O_APPEND)) == FWRITE)
301		error = EPERM;
302	else {
303		error = 0;
304		/* For regular files, the call below is nop. */
305		KASSERT(vp->v_type != VREG || (node->tn_reg.tn_aobj->flags &
306		    OBJ_DEAD) == 0, ("dead object"));
307		vnode_create_vobject(vp, node->tn_size, v->a_td);
308	}
309
310	MPASS(VOP_ISLOCKED(vp));
311	return error;
312}
313
314static int
315tmpfs_close(struct vop_close_args *v)
316{
317	struct vnode *vp = v->a_vp;
318
319	/* Update node times. */
320	tmpfs_update(vp);
321
322	return (0);
323}
324
325int
326tmpfs_access(struct vop_access_args *v)
327{
328	struct vnode *vp = v->a_vp;
329	accmode_t accmode = v->a_accmode;
330	struct ucred *cred = v->a_cred;
331
332	int error;
333	struct tmpfs_node *node;
334
335	MPASS(VOP_ISLOCKED(vp));
336
337	node = VP_TO_TMPFS_NODE(vp);
338
339	switch (vp->v_type) {
340	case VDIR:
341		/* FALLTHROUGH */
342	case VLNK:
343		/* FALLTHROUGH */
344	case VREG:
345		if (accmode & VWRITE && vp->v_mount->mnt_flag & MNT_RDONLY) {
346			error = EROFS;
347			goto out;
348		}
349		break;
350
351	case VBLK:
352		/* FALLTHROUGH */
353	case VCHR:
354		/* FALLTHROUGH */
355	case VSOCK:
356		/* FALLTHROUGH */
357	case VFIFO:
358		break;
359
360	default:
361		error = EINVAL;
362		goto out;
363	}
364
365	if (accmode & VWRITE && node->tn_flags & IMMUTABLE) {
366		error = EPERM;
367		goto out;
368	}
369
370	error = vaccess(vp->v_type, node->tn_mode, node->tn_uid,
371	    node->tn_gid, accmode, cred, NULL);
372
373out:
374	MPASS(VOP_ISLOCKED(vp));
375
376	return (error);
377}
378
379int
380tmpfs_getattr(struct vop_getattr_args *v)
381{
382	struct vnode *vp = v->a_vp;
383	struct vattr *vap = v->a_vap;
384	vm_object_t obj;
385	struct tmpfs_node *node;
386
387	node = VP_TO_TMPFS_NODE(vp);
388
389	tmpfs_update(vp);
390
391	vap->va_type = vp->v_type;
392	vap->va_mode = node->tn_mode;
393	vap->va_nlink = node->tn_links;
394	vap->va_uid = node->tn_uid;
395	vap->va_gid = node->tn_gid;
396	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
397	vap->va_fileid = node->tn_id;
398	vap->va_size = node->tn_size;
399	vap->va_blocksize = PAGE_SIZE;
400	vap->va_atime = node->tn_atime;
401	vap->va_mtime = node->tn_mtime;
402	vap->va_ctime = node->tn_ctime;
403	vap->va_birthtime = node->tn_birthtime;
404	vap->va_gen = node->tn_gen;
405	vap->va_flags = node->tn_flags;
406	vap->va_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ?
407		node->tn_rdev : NODEV;
408	if (vp->v_type == VREG) {
409		obj = node->tn_reg.tn_aobj;
410		vap->va_bytes = (u_quad_t)obj->resident_page_count * PAGE_SIZE;
411	} else
412		vap->va_bytes = node->tn_size;
413	vap->va_filerev = 0;
414
415	return 0;
416}
417
418int
419tmpfs_setattr(struct vop_setattr_args *v)
420{
421	struct vnode *vp = v->a_vp;
422	struct vattr *vap = v->a_vap;
423	struct ucred *cred = v->a_cred;
424	struct thread *td = curthread;
425
426	int error;
427
428	MPASS(VOP_ISLOCKED(vp));
429
430	error = 0;
431
432	/* Abort if any unsettable attribute is given. */
433	if (vap->va_type != VNON ||
434	    vap->va_nlink != VNOVAL ||
435	    vap->va_fsid != VNOVAL ||
436	    vap->va_fileid != VNOVAL ||
437	    vap->va_blocksize != VNOVAL ||
438	    vap->va_gen != VNOVAL ||
439	    vap->va_rdev != VNOVAL ||
440	    vap->va_bytes != VNOVAL)
441		error = EINVAL;
442
443	if (error == 0 && (vap->va_flags != VNOVAL))
444		error = tmpfs_chflags(vp, vap->va_flags, cred, td);
445
446	if (error == 0 && (vap->va_size != VNOVAL))
447		error = tmpfs_chsize(vp, vap->va_size, cred, td);
448
449	if (error == 0 && (vap->va_uid != VNOVAL || vap->va_gid != VNOVAL))
450		error = tmpfs_chown(vp, vap->va_uid, vap->va_gid, cred, td);
451
452	if (error == 0 && (vap->va_mode != (mode_t)VNOVAL))
453		error = tmpfs_chmod(vp, vap->va_mode, cred, td);
454
455	if (error == 0 && ((vap->va_atime.tv_sec != VNOVAL &&
456	    vap->va_atime.tv_nsec != VNOVAL) ||
457	    (vap->va_mtime.tv_sec != VNOVAL &&
458	    vap->va_mtime.tv_nsec != VNOVAL) ||
459	    (vap->va_birthtime.tv_sec != VNOVAL &&
460	    vap->va_birthtime.tv_nsec != VNOVAL)))
461		error = tmpfs_chtimes(vp, vap, cred, td);
462
463	/*
464	 * Update the node times.  We give preference to the error codes
465	 * generated by this function rather than the ones that may arise
466	 * from tmpfs_update.
467	 */
468	tmpfs_update(vp);
469
470	MPASS(VOP_ISLOCKED(vp));
471
472	return error;
473}
474
475static int
476tmpfs_read(struct vop_read_args *v)
477{
478	struct vnode *vp;
479	struct uio *uio;
480	struct tmpfs_node *node;
481
482	vp = v->a_vp;
483	if (vp->v_type != VREG)
484		return (EISDIR);
485	uio = v->a_uio;
486	if (uio->uio_offset < 0)
487		return (EINVAL);
488	node = VP_TO_TMPFS_NODE(vp);
489	tmpfs_set_status(VFS_TO_TMPFS(vp->v_mount), node, TMPFS_NODE_ACCESSED);
490	return (uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio));
491}
492
493static int
494tmpfs_write(struct vop_write_args *v)
495{
496	struct vnode *vp;
497	struct uio *uio;
498	struct tmpfs_node *node;
499	off_t oldsize;
500	int error, ioflag;
501
502	vp = v->a_vp;
503	uio = v->a_uio;
504	ioflag = v->a_ioflag;
505	error = 0;
506	node = VP_TO_TMPFS_NODE(vp);
507	oldsize = node->tn_size;
508
509	if (uio->uio_offset < 0 || vp->v_type != VREG)
510		return (EINVAL);
511	if (uio->uio_resid == 0)
512		return (0);
513	if (ioflag & IO_APPEND)
514		uio->uio_offset = node->tn_size;
515	if (uio->uio_offset + uio->uio_resid >
516	  VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize)
517		return (EFBIG);
518	if (vn_rlimit_fsize(vp, uio, uio->uio_td))
519		return (EFBIG);
520	if (uio->uio_offset + uio->uio_resid > node->tn_size) {
521		error = tmpfs_reg_resize(vp, uio->uio_offset + uio->uio_resid,
522		    FALSE);
523		if (error != 0)
524			goto out;
525	}
526
527	error = uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio);
528	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED |
529	    TMPFS_NODE_CHANGED;
530	if (node->tn_mode & (S_ISUID | S_ISGID)) {
531		if (priv_check_cred(v->a_cred, PRIV_VFS_RETAINSUGID, 0))
532			node->tn_mode &= ~(S_ISUID | S_ISGID);
533	}
534	if (error != 0)
535		(void)tmpfs_reg_resize(vp, oldsize, TRUE);
536
537out:
538	MPASS(IMPLIES(error == 0, uio->uio_resid == 0));
539	MPASS(IMPLIES(error != 0, oldsize == node->tn_size));
540
541	return (error);
542}
543
544static int
545tmpfs_fsync(struct vop_fsync_args *v)
546{
547	struct vnode *vp = v->a_vp;
548
549	MPASS(VOP_ISLOCKED(vp));
550
551	tmpfs_check_mtime(vp);
552	tmpfs_update(vp);
553
554	return 0;
555}
556
557static int
558tmpfs_remove(struct vop_remove_args *v)
559{
560	struct vnode *dvp = v->a_dvp;
561	struct vnode *vp = v->a_vp;
562
563	int error;
564	struct tmpfs_dirent *de;
565	struct tmpfs_mount *tmp;
566	struct tmpfs_node *dnode;
567	struct tmpfs_node *node;
568
569	MPASS(VOP_ISLOCKED(dvp));
570	MPASS(VOP_ISLOCKED(vp));
571
572	if (vp->v_type == VDIR) {
573		error = EISDIR;
574		goto out;
575	}
576
577	dnode = VP_TO_TMPFS_DIR(dvp);
578	node = VP_TO_TMPFS_NODE(vp);
579	tmp = VFS_TO_TMPFS(vp->v_mount);
580	de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
581	MPASS(de != NULL);
582
583	/* Files marked as immutable or append-only cannot be deleted. */
584	if ((node->tn_flags & (IMMUTABLE | APPEND | NOUNLINK)) ||
585	    (dnode->tn_flags & APPEND)) {
586		error = EPERM;
587		goto out;
588	}
589
590	/* Remove the entry from the directory; as it is a file, we do not
591	 * have to change the number of hard links of the directory. */
592	tmpfs_dir_detach(dvp, de);
593	if (v->a_cnp->cn_flags & DOWHITEOUT)
594		tmpfs_dir_whiteout_add(dvp, v->a_cnp);
595
596	/* Free the directory entry we just deleted.  Note that the node
597	 * referred by it will not be removed until the vnode is really
598	 * reclaimed. */
599	tmpfs_free_dirent(tmp, de);
600
601	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED;
602	error = 0;
603
604out:
605	return (error);
606}
607
608static int
609tmpfs_link(struct vop_link_args *v)
610{
611	struct vnode *dvp = v->a_tdvp;
612	struct vnode *vp = v->a_vp;
613	struct componentname *cnp = v->a_cnp;
614
615	int error;
616	struct tmpfs_dirent *de;
617	struct tmpfs_node *node;
618
619	MPASS(VOP_ISLOCKED(dvp));
620	MPASS(cnp->cn_flags & HASBUF);
621	MPASS(dvp != vp); /* XXX When can this be false? */
622	node = VP_TO_TMPFS_NODE(vp);
623
624	/* Ensure that we do not overflow the maximum number of links imposed
625	 * by the system. */
626	MPASS(node->tn_links <= TMPFS_LINK_MAX);
627	if (node->tn_links == TMPFS_LINK_MAX) {
628		error = EMLINK;
629		goto out;
630	}
631
632	/* We cannot create links of files marked immutable or append-only. */
633	if (node->tn_flags & (IMMUTABLE | APPEND)) {
634		error = EPERM;
635		goto out;
636	}
637
638	/* Allocate a new directory entry to represent the node. */
639	error = tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount), node,
640	    cnp->cn_nameptr, cnp->cn_namelen, &de);
641	if (error != 0)
642		goto out;
643
644	/* Insert the new directory entry into the appropriate directory. */
645	if (cnp->cn_flags & ISWHITEOUT)
646		tmpfs_dir_whiteout_remove(dvp, cnp);
647	tmpfs_dir_attach(dvp, de);
648
649	/* vp link count has changed, so update node times. */
650	node->tn_status |= TMPFS_NODE_CHANGED;
651	tmpfs_update(vp);
652
653	error = 0;
654
655out:
656	return error;
657}
658
659/*
660 * We acquire all but fdvp locks using non-blocking acquisitions.  If we
661 * fail to acquire any lock in the path we will drop all held locks,
662 * acquire the new lock in a blocking fashion, and then release it and
663 * restart the rename.  This acquire/release step ensures that we do not
664 * spin on a lock waiting for release.  On error release all vnode locks
665 * and decrement references the way tmpfs_rename() would do.
666 */
667static int
668tmpfs_rename_relock(struct vnode *fdvp, struct vnode **fvpp,
669    struct vnode *tdvp, struct vnode **tvpp,
670    struct componentname *fcnp, struct componentname *tcnp)
671{
672	struct vnode *nvp;
673	struct mount *mp;
674	struct tmpfs_dirent *de;
675	int error, restarts = 0;
676
677	VOP_UNLOCK(tdvp, 0);
678	if (*tvpp != NULL && *tvpp != tdvp)
679		VOP_UNLOCK(*tvpp, 0);
680	mp = fdvp->v_mount;
681
682relock:
683	restarts += 1;
684	error = vn_lock(fdvp, LK_EXCLUSIVE);
685	if (error)
686		goto releout;
687	if (vn_lock(tdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
688		VOP_UNLOCK(fdvp, 0);
689		error = vn_lock(tdvp, LK_EXCLUSIVE);
690		if (error)
691			goto releout;
692		VOP_UNLOCK(tdvp, 0);
693		goto relock;
694	}
695	/*
696	 * Re-resolve fvp to be certain it still exists and fetch the
697	 * correct vnode.
698	 */
699	de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(fdvp), NULL, fcnp);
700	if (de == NULL) {
701		VOP_UNLOCK(fdvp, 0);
702		VOP_UNLOCK(tdvp, 0);
703		if ((fcnp->cn_flags & ISDOTDOT) != 0 ||
704		    (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.'))
705			error = EINVAL;
706		else
707			error = ENOENT;
708		goto releout;
709	}
710	error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp);
711	if (error != 0) {
712		VOP_UNLOCK(fdvp, 0);
713		VOP_UNLOCK(tdvp, 0);
714		if (error != EBUSY)
715			goto releout;
716		error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp);
717		if (error != 0)
718			goto releout;
719		VOP_UNLOCK(nvp, 0);
720		/*
721		 * Concurrent rename race.
722		 */
723		if (nvp == tdvp) {
724			vrele(nvp);
725			error = EINVAL;
726			goto releout;
727		}
728		vrele(*fvpp);
729		*fvpp = nvp;
730		goto relock;
731	}
732	vrele(*fvpp);
733	*fvpp = nvp;
734	VOP_UNLOCK(*fvpp, 0);
735	/*
736	 * Re-resolve tvp and acquire the vnode lock if present.
737	 */
738	de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(tdvp), NULL, tcnp);
739	/*
740	 * If tvp disappeared we just carry on.
741	 */
742	if (de == NULL && *tvpp != NULL) {
743		vrele(*tvpp);
744		*tvpp = NULL;
745	}
746	/*
747	 * Get the tvp ino if the lookup succeeded.  We may have to restart
748	 * if the non-blocking acquire fails.
749	 */
750	if (de != NULL) {
751		nvp = NULL;
752		error = tmpfs_alloc_vp(mp, de->td_node,
753		    LK_EXCLUSIVE | LK_NOWAIT, &nvp);
754		if (*tvpp != NULL)
755			vrele(*tvpp);
756		*tvpp = nvp;
757		if (error != 0) {
758			VOP_UNLOCK(fdvp, 0);
759			VOP_UNLOCK(tdvp, 0);
760			if (error != EBUSY)
761				goto releout;
762			error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE,
763			    &nvp);
764			if (error != 0)
765				goto releout;
766			VOP_UNLOCK(nvp, 0);
767			/*
768			 * fdvp contains fvp, thus tvp (=fdvp) is not empty.
769			 */
770			if (nvp == fdvp) {
771				error = ENOTEMPTY;
772				goto releout;
773			}
774			goto relock;
775		}
776	}
777	tmpfs_rename_restarts += restarts;
778
779	return (0);
780
781releout:
782	vrele(fdvp);
783	vrele(*fvpp);
784	vrele(tdvp);
785	if (*tvpp != NULL)
786		vrele(*tvpp);
787	tmpfs_rename_restarts += restarts;
788
789	return (error);
790}
791
792static int
793tmpfs_rename(struct vop_rename_args *v)
794{
795	struct vnode *fdvp = v->a_fdvp;
796	struct vnode *fvp = v->a_fvp;
797	struct componentname *fcnp = v->a_fcnp;
798	struct vnode *tdvp = v->a_tdvp;
799	struct vnode *tvp = v->a_tvp;
800	struct componentname *tcnp = v->a_tcnp;
801	char *newname;
802	struct tmpfs_dirent *de;
803	struct tmpfs_mount *tmp;
804	struct tmpfs_node *fdnode;
805	struct tmpfs_node *fnode;
806	struct tmpfs_node *tnode;
807	struct tmpfs_node *tdnode;
808	int error;
809
810	MPASS(VOP_ISLOCKED(tdvp));
811	MPASS(IMPLIES(tvp != NULL, VOP_ISLOCKED(tvp)));
812	MPASS(fcnp->cn_flags & HASBUF);
813	MPASS(tcnp->cn_flags & HASBUF);
814
815	/*
816	 * Disallow cross-device renames.
817	 * XXX Why isn't this done by the caller?
818	 */
819	if (fvp->v_mount != tdvp->v_mount ||
820	    (tvp != NULL && fvp->v_mount != tvp->v_mount)) {
821		error = EXDEV;
822		goto out;
823	}
824
825	/* If source and target are the same file, there is nothing to do. */
826	if (fvp == tvp) {
827		error = 0;
828		goto out;
829	}
830
831	/*
832	 * If we need to move the directory between entries, lock the
833	 * source so that we can safely operate on it.
834	 */
835	if (fdvp != tdvp && fdvp != tvp) {
836		if (vn_lock(fdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
837			error = tmpfs_rename_relock(fdvp, &fvp, tdvp, &tvp,
838			    fcnp, tcnp);
839			if (error != 0)
840				return (error);
841			ASSERT_VOP_ELOCKED(fdvp,
842			    "tmpfs_rename: fdvp not locked");
843			ASSERT_VOP_ELOCKED(tdvp,
844			    "tmpfs_rename: tdvp not locked");
845			if (tvp != NULL)
846				ASSERT_VOP_ELOCKED(tvp,
847				    "tmpfs_rename: tvp not locked");
848			if (fvp == tvp) {
849				error = 0;
850				goto out_locked;
851			}
852		}
853	}
854
855	tmp = VFS_TO_TMPFS(tdvp->v_mount);
856	tdnode = VP_TO_TMPFS_DIR(tdvp);
857	tnode = (tvp == NULL) ? NULL : VP_TO_TMPFS_NODE(tvp);
858	fdnode = VP_TO_TMPFS_DIR(fdvp);
859	fnode = VP_TO_TMPFS_NODE(fvp);
860	de = tmpfs_dir_lookup(fdnode, fnode, fcnp);
861
862	/*
863	 * Entry can disappear before we lock fdvp,
864	 * also avoid manipulating '.' and '..' entries.
865	 */
866	if (de == NULL) {
867		if ((fcnp->cn_flags & ISDOTDOT) != 0 ||
868		    (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.'))
869			error = EINVAL;
870		else
871			error = ENOENT;
872		goto out_locked;
873	}
874	MPASS(de->td_node == fnode);
875
876	/*
877	 * If re-naming a directory to another preexisting directory
878	 * ensure that the target directory is empty so that its
879	 * removal causes no side effects.
880	 * Kern_rename guarantees the destination to be a directory
881	 * if the source is one.
882	 */
883	if (tvp != NULL) {
884		MPASS(tnode != NULL);
885
886		if ((tnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
887		    (tdnode->tn_flags & (APPEND | IMMUTABLE))) {
888			error = EPERM;
889			goto out_locked;
890		}
891
892		if (fnode->tn_type == VDIR && tnode->tn_type == VDIR) {
893			if (tnode->tn_size > 0) {
894				error = ENOTEMPTY;
895				goto out_locked;
896			}
897		} else if (fnode->tn_type == VDIR && tnode->tn_type != VDIR) {
898			error = ENOTDIR;
899			goto out_locked;
900		} else if (fnode->tn_type != VDIR && tnode->tn_type == VDIR) {
901			error = EISDIR;
902			goto out_locked;
903		} else {
904			MPASS(fnode->tn_type != VDIR &&
905				tnode->tn_type != VDIR);
906		}
907	}
908
909	if ((fnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))
910	    || (fdnode->tn_flags & (APPEND | IMMUTABLE))) {
911		error = EPERM;
912		goto out_locked;
913	}
914
915	/*
916	 * Ensure that we have enough memory to hold the new name, if it
917	 * has to be changed.
918	 */
919	if (fcnp->cn_namelen != tcnp->cn_namelen ||
920	    bcmp(fcnp->cn_nameptr, tcnp->cn_nameptr, fcnp->cn_namelen) != 0) {
921		newname = malloc(tcnp->cn_namelen, M_TMPFSNAME, M_WAITOK);
922	} else
923		newname = NULL;
924
925	/*
926	 * If the node is being moved to another directory, we have to do
927	 * the move.
928	 */
929	if (fdnode != tdnode) {
930		/*
931		 * In case we are moving a directory, we have to adjust its
932		 * parent to point to the new parent.
933		 */
934		if (de->td_node->tn_type == VDIR) {
935			struct tmpfs_node *n;
936
937			/*
938			 * Ensure the target directory is not a child of the
939			 * directory being moved.  Otherwise, we'd end up
940			 * with stale nodes.
941			 */
942			n = tdnode;
943			/*
944			 * TMPFS_LOCK guaranties that no nodes are freed while
945			 * traversing the list. Nodes can only be marked as
946			 * removed: tn_parent == NULL.
947			 */
948			TMPFS_LOCK(tmp);
949			TMPFS_NODE_LOCK(n);
950			while (n != n->tn_dir.tn_parent) {
951				struct tmpfs_node *parent;
952
953				if (n == fnode) {
954					TMPFS_NODE_UNLOCK(n);
955					TMPFS_UNLOCK(tmp);
956					error = EINVAL;
957					if (newname != NULL)
958						    free(newname, M_TMPFSNAME);
959					goto out_locked;
960				}
961				parent = n->tn_dir.tn_parent;
962				TMPFS_NODE_UNLOCK(n);
963				if (parent == NULL) {
964					n = NULL;
965					break;
966				}
967				TMPFS_NODE_LOCK(parent);
968				if (parent->tn_dir.tn_parent == NULL) {
969					TMPFS_NODE_UNLOCK(parent);
970					n = NULL;
971					break;
972				}
973				n = parent;
974			}
975			TMPFS_UNLOCK(tmp);
976			if (n == NULL) {
977				error = EINVAL;
978				if (newname != NULL)
979					    free(newname, M_TMPFSNAME);
980				goto out_locked;
981			}
982			TMPFS_NODE_UNLOCK(n);
983
984			/* Adjust the parent pointer. */
985			TMPFS_VALIDATE_DIR(fnode);
986			TMPFS_NODE_LOCK(de->td_node);
987			de->td_node->tn_dir.tn_parent = tdnode;
988			TMPFS_NODE_UNLOCK(de->td_node);
989
990			/*
991			 * As a result of changing the target of the '..'
992			 * entry, the link count of the source and target
993			 * directories has to be adjusted.
994			 */
995			TMPFS_NODE_LOCK(tdnode);
996			TMPFS_ASSERT_LOCKED(tdnode);
997			tdnode->tn_links++;
998			TMPFS_NODE_UNLOCK(tdnode);
999
1000			TMPFS_NODE_LOCK(fdnode);
1001			TMPFS_ASSERT_LOCKED(fdnode);
1002			fdnode->tn_links--;
1003			TMPFS_NODE_UNLOCK(fdnode);
1004		}
1005	}
1006
1007	/*
1008	 * Do the move: just remove the entry from the source directory
1009	 * and insert it into the target one.
1010	 */
1011	tmpfs_dir_detach(fdvp, de);
1012
1013	if (fcnp->cn_flags & DOWHITEOUT)
1014		tmpfs_dir_whiteout_add(fdvp, fcnp);
1015	if (tcnp->cn_flags & ISWHITEOUT)
1016		tmpfs_dir_whiteout_remove(tdvp, tcnp);
1017
1018	/*
1019	 * If the name has changed, we need to make it effective by changing
1020	 * it in the directory entry.
1021	 */
1022	if (newname != NULL) {
1023		MPASS(tcnp->cn_namelen <= MAXNAMLEN);
1024
1025		free(de->ud.td_name, M_TMPFSNAME);
1026		de->ud.td_name = newname;
1027		tmpfs_dirent_init(de, tcnp->cn_nameptr, tcnp->cn_namelen);
1028
1029		fnode->tn_status |= TMPFS_NODE_CHANGED;
1030		tdnode->tn_status |= TMPFS_NODE_MODIFIED;
1031	}
1032
1033	/*
1034	 * If we are overwriting an entry, we have to remove the old one
1035	 * from the target directory.
1036	 */
1037	if (tvp != NULL) {
1038		struct tmpfs_dirent *tde;
1039
1040		/* Remove the old entry from the target directory. */
1041		tde = tmpfs_dir_lookup(tdnode, tnode, tcnp);
1042		tmpfs_dir_detach(tdvp, tde);
1043
1044		/*
1045		 * Free the directory entry we just deleted.  Note that the
1046		 * node referred by it will not be removed until the vnode is
1047		 * really reclaimed.
1048		 */
1049		tmpfs_free_dirent(VFS_TO_TMPFS(tvp->v_mount), tde);
1050	}
1051
1052	tmpfs_dir_attach(tdvp, de);
1053
1054	if (tmpfs_use_nc(fvp)) {
1055		cache_purge(fvp);
1056		if (tvp != NULL)
1057			cache_purge(tvp);
1058		cache_purge_negative(tdvp);
1059	}
1060
1061	error = 0;
1062
1063out_locked:
1064	if (fdvp != tdvp && fdvp != tvp)
1065		VOP_UNLOCK(fdvp, 0);
1066
1067out:
1068	/*
1069	 * Release target nodes.
1070	 * XXX: I don't understand when tdvp can be the same as tvp, but
1071	 * other code takes care of this...
1072	 */
1073	if (tdvp == tvp)
1074		vrele(tdvp);
1075	else
1076		vput(tdvp);
1077	if (tvp != NULL)
1078		vput(tvp);
1079
1080	/* Release source nodes. */
1081	vrele(fdvp);
1082	vrele(fvp);
1083
1084	return (error);
1085}
1086
1087static int
1088tmpfs_mkdir(struct vop_mkdir_args *v)
1089{
1090	struct vnode *dvp = v->a_dvp;
1091	struct vnode **vpp = v->a_vpp;
1092	struct componentname *cnp = v->a_cnp;
1093	struct vattr *vap = v->a_vap;
1094
1095	MPASS(vap->va_type == VDIR);
1096
1097	return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
1098}
1099
1100static int
1101tmpfs_rmdir(struct vop_rmdir_args *v)
1102{
1103	struct vnode *dvp = v->a_dvp;
1104	struct vnode *vp = v->a_vp;
1105
1106	int error;
1107	struct tmpfs_dirent *de;
1108	struct tmpfs_mount *tmp;
1109	struct tmpfs_node *dnode;
1110	struct tmpfs_node *node;
1111
1112	MPASS(VOP_ISLOCKED(dvp));
1113	MPASS(VOP_ISLOCKED(vp));
1114
1115	tmp = VFS_TO_TMPFS(dvp->v_mount);
1116	dnode = VP_TO_TMPFS_DIR(dvp);
1117	node = VP_TO_TMPFS_DIR(vp);
1118
1119	/* Directories with more than two entries ('.' and '..') cannot be
1120	 * removed. */
1121	 if (node->tn_size > 0) {
1122		 error = ENOTEMPTY;
1123		 goto out;
1124	 }
1125
1126	if ((dnode->tn_flags & APPEND)
1127	    || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
1128		error = EPERM;
1129		goto out;
1130	}
1131
1132	/* This invariant holds only if we are not trying to remove "..".
1133	  * We checked for that above so this is safe now. */
1134	MPASS(node->tn_dir.tn_parent == dnode);
1135
1136	/* Get the directory entry associated with node (vp).  This was
1137	 * filled by tmpfs_lookup while looking up the entry. */
1138	de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
1139	MPASS(TMPFS_DIRENT_MATCHES(de,
1140	    v->a_cnp->cn_nameptr,
1141	    v->a_cnp->cn_namelen));
1142
1143	/* Check flags to see if we are allowed to remove the directory. */
1144	if ((dnode->tn_flags & APPEND) != 0 ||
1145	    (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) != 0) {
1146		error = EPERM;
1147		goto out;
1148	}
1149
1150
1151	/* Detach the directory entry from the directory (dnode). */
1152	tmpfs_dir_detach(dvp, de);
1153	if (v->a_cnp->cn_flags & DOWHITEOUT)
1154		tmpfs_dir_whiteout_add(dvp, v->a_cnp);
1155
1156	/* No vnode should be allocated for this entry from this point */
1157	TMPFS_NODE_LOCK(node);
1158	node->tn_links--;
1159	node->tn_dir.tn_parent = NULL;
1160	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
1161	    TMPFS_NODE_MODIFIED;
1162
1163	TMPFS_NODE_UNLOCK(node);
1164
1165	TMPFS_NODE_LOCK(dnode);
1166	dnode->tn_links--;
1167	dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
1168	    TMPFS_NODE_MODIFIED;
1169	TMPFS_NODE_UNLOCK(dnode);
1170
1171	if (tmpfs_use_nc(dvp)) {
1172		cache_purge(dvp);
1173		cache_purge(vp);
1174	}
1175
1176	/* Free the directory entry we just deleted.  Note that the node
1177	 * referred by it will not be removed until the vnode is really
1178	 * reclaimed. */
1179	tmpfs_free_dirent(tmp, de);
1180
1181	/* Release the deleted vnode (will destroy the node, notify
1182	 * interested parties and clean it from the cache). */
1183
1184	dnode->tn_status |= TMPFS_NODE_CHANGED;
1185	tmpfs_update(dvp);
1186
1187	error = 0;
1188
1189out:
1190	return error;
1191}
1192
1193static int
1194tmpfs_symlink(struct vop_symlink_args *v)
1195{
1196	struct vnode *dvp = v->a_dvp;
1197	struct vnode **vpp = v->a_vpp;
1198	struct componentname *cnp = v->a_cnp;
1199	struct vattr *vap = v->a_vap;
1200	char *target = v->a_target;
1201
1202#ifdef notyet /* XXX FreeBSD BUG: kern_symlink is not setting VLNK */
1203	MPASS(vap->va_type == VLNK);
1204#else
1205	vap->va_type = VLNK;
1206#endif
1207
1208	return tmpfs_alloc_file(dvp, vpp, vap, cnp, target);
1209}
1210
1211static int
1212tmpfs_readdir(struct vop_readdir_args *va)
1213{
1214	struct vnode *vp;
1215	struct uio *uio;
1216	struct tmpfs_mount *tm;
1217	struct tmpfs_node *node;
1218	u_long **cookies;
1219	int *eofflag, *ncookies;
1220	ssize_t startresid;
1221	int error, maxcookies;
1222
1223	vp = va->a_vp;
1224	uio = va->a_uio;
1225	eofflag = va->a_eofflag;
1226	cookies = va->a_cookies;
1227	ncookies = va->a_ncookies;
1228
1229	/* This operation only makes sense on directory nodes. */
1230	if (vp->v_type != VDIR)
1231		return ENOTDIR;
1232
1233	maxcookies = 0;
1234	node = VP_TO_TMPFS_DIR(vp);
1235	tm = VFS_TO_TMPFS(vp->v_mount);
1236
1237	startresid = uio->uio_resid;
1238
1239	/* Allocate cookies for NFS and compat modules. */
1240	if (cookies != NULL && ncookies != NULL) {
1241		maxcookies = howmany(node->tn_size,
1242		    sizeof(struct tmpfs_dirent)) + 2;
1243		*cookies = malloc(maxcookies * sizeof(**cookies), M_TEMP,
1244		    M_WAITOK);
1245		*ncookies = 0;
1246	}
1247
1248	if (cookies == NULL)
1249		error = tmpfs_dir_getdents(tm, node, uio, 0, NULL, NULL);
1250	else
1251		error = tmpfs_dir_getdents(tm, node, uio, maxcookies, *cookies,
1252		    ncookies);
1253
1254	/* Buffer was filled without hitting EOF. */
1255	if (error == EJUSTRETURN)
1256		error = (uio->uio_resid != startresid) ? 0 : EINVAL;
1257
1258	if (error != 0 && cookies != NULL && ncookies != NULL) {
1259		free(*cookies, M_TEMP);
1260		*cookies = NULL;
1261		*ncookies = 0;
1262	}
1263
1264	if (eofflag != NULL)
1265		*eofflag =
1266		    (error == 0 && uio->uio_offset == TMPFS_DIRCOOKIE_EOF);
1267
1268	return error;
1269}
1270
1271static int
1272tmpfs_readlink(struct vop_readlink_args *v)
1273{
1274	struct vnode *vp = v->a_vp;
1275	struct uio *uio = v->a_uio;
1276
1277	int error;
1278	struct tmpfs_node *node;
1279
1280	MPASS(uio->uio_offset == 0);
1281	MPASS(vp->v_type == VLNK);
1282
1283	node = VP_TO_TMPFS_NODE(vp);
1284
1285	error = uiomove(node->tn_link, MIN(node->tn_size, uio->uio_resid),
1286	    uio);
1287	tmpfs_set_status(VFS_TO_TMPFS(vp->v_mount), node, TMPFS_NODE_ACCESSED);
1288
1289	return (error);
1290}
1291
1292static int
1293tmpfs_inactive(struct vop_inactive_args *v)
1294{
1295	struct vnode *vp;
1296	struct tmpfs_node *node;
1297
1298	vp = v->a_vp;
1299	node = VP_TO_TMPFS_NODE(vp);
1300	if (node->tn_links == 0)
1301		vrecycle(vp);
1302	else
1303		tmpfs_check_mtime(vp);
1304	return (0);
1305}
1306
1307int
1308tmpfs_reclaim(struct vop_reclaim_args *v)
1309{
1310	struct vnode *vp;
1311	struct tmpfs_mount *tmp;
1312	struct tmpfs_node *node;
1313	bool unlock, tm_locked;
1314
1315	vp = v->a_vp;
1316	node = VP_TO_TMPFS_NODE(vp);
1317	tmp = VFS_TO_TMPFS(vp->v_mount);
1318	tm_locked = false;
1319
1320	if (vp->v_type == VREG)
1321		tmpfs_destroy_vobject(vp, node->tn_reg.tn_aobj);
1322	else
1323		vnode_destroy_vobject(vp);
1324	vp->v_object = NULL;
1325	if (tmpfs_use_nc(vp))
1326		cache_purge(vp);
1327
1328relock:
1329	TMPFS_NODE_LOCK(node);
1330	if (!tm_locked && node->tn_links == 0 &&
1331	    (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) {
1332		TMPFS_NODE_UNLOCK(node);
1333		TMPFS_LOCK(tmp);
1334		tm_locked = true;
1335		goto relock;
1336	}
1337	tmpfs_free_vp(vp);
1338
1339	/*
1340	 * If the node referenced by this vnode was deleted by the user,
1341	 * we must free its associated data structures (now that the vnode
1342	 * is being reclaimed).
1343	 */
1344	if (node->tn_links == 0 &&
1345	    (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) {
1346		MPASS(tm_locked);
1347		node->tn_vpstate = TMPFS_VNODE_DOOMED;
1348		unlock = !tmpfs_free_node_locked(tmp, node, true);
1349	} else {
1350		unlock = true;
1351	}
1352
1353	if (unlock) {
1354		TMPFS_NODE_UNLOCK(node);
1355		if (tm_locked)
1356			TMPFS_UNLOCK(tmp);
1357	}
1358
1359	MPASS(vp->v_data == NULL);
1360	return (0);
1361}
1362
1363int
1364tmpfs_print(struct vop_print_args *v)
1365{
1366	struct vnode *vp = v->a_vp;
1367
1368	struct tmpfs_node *node;
1369
1370	node = VP_TO_TMPFS_NODE(vp);
1371
1372	printf("tag VT_TMPFS, tmpfs_node %p, flags 0x%lx, links %jd\n",
1373	    node, node->tn_flags, (uintmax_t)node->tn_links);
1374	printf("\tmode 0%o, owner %d, group %d, size %jd, status 0x%x\n",
1375	    node->tn_mode, node->tn_uid, node->tn_gid,
1376	    (intmax_t)node->tn_size, node->tn_status);
1377
1378	if (vp->v_type == VFIFO)
1379		fifo_printinfo(vp);
1380
1381	printf("\n");
1382
1383	return 0;
1384}
1385
1386int
1387tmpfs_pathconf(struct vop_pathconf_args *v)
1388{
1389	struct vnode *vp = v->a_vp;
1390	int name = v->a_name;
1391	long *retval = v->a_retval;
1392
1393	int error;
1394
1395	error = 0;
1396
1397	switch (name) {
1398	case _PC_LINK_MAX:
1399		*retval = TMPFS_LINK_MAX;
1400		break;
1401
1402	case _PC_NAME_MAX:
1403		*retval = NAME_MAX;
1404		break;
1405
1406	case _PC_PIPE_BUF:
1407		if (vp->v_type == VDIR || vp->v_type == VFIFO)
1408			*retval = PIPE_BUF;
1409		else
1410			error = EINVAL;
1411		break;
1412
1413	case _PC_CHOWN_RESTRICTED:
1414		*retval = 1;
1415		break;
1416
1417	case _PC_NO_TRUNC:
1418		*retval = 1;
1419		break;
1420
1421	case _PC_SYNC_IO:
1422		*retval = 1;
1423		break;
1424
1425	case _PC_FILESIZEBITS:
1426		*retval = 64;
1427		break;
1428
1429	default:
1430		error = vop_stdpathconf(v);
1431	}
1432
1433	return error;
1434}
1435
1436static int
1437tmpfs_vptofh(struct vop_vptofh_args *ap)
1438/*
1439vop_vptofh {
1440	IN struct vnode *a_vp;
1441	IN struct fid *a_fhp;
1442};
1443*/
1444{
1445	struct tmpfs_fid_data tfd;
1446	struct tmpfs_node *node;
1447	struct fid *fhp;
1448
1449	node = VP_TO_TMPFS_NODE(ap->a_vp);
1450	fhp = ap->a_fhp;
1451	fhp->fid_len = sizeof(tfd);
1452
1453	/*
1454	 * Copy into fid_data from the stack to avoid unaligned pointer use.
1455	 * See the comment in sys/mount.h on struct fid for details.
1456	 */
1457	tfd.tfd_id = node->tn_id;
1458	tfd.tfd_gen = node->tn_gen;
1459	memcpy(fhp->fid_data, &tfd, fhp->fid_len);
1460
1461	return (0);
1462}
1463
1464static int
1465tmpfs_whiteout(struct vop_whiteout_args *ap)
1466{
1467	struct vnode *dvp = ap->a_dvp;
1468	struct componentname *cnp = ap->a_cnp;
1469	struct tmpfs_dirent *de;
1470
1471	switch (ap->a_flags) {
1472	case LOOKUP:
1473		return (0);
1474	case CREATE:
1475		de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(dvp), NULL, cnp);
1476		if (de != NULL)
1477			return (de->td_node == NULL ? 0 : EEXIST);
1478		return (tmpfs_dir_whiteout_add(dvp, cnp));
1479	case DELETE:
1480		tmpfs_dir_whiteout_remove(dvp, cnp);
1481		return (0);
1482	default:
1483		panic("tmpfs_whiteout: unknown op");
1484	}
1485}
1486
1487static int
1488tmpfs_vptocnp_dir(struct tmpfs_node *tn, struct tmpfs_node *tnp,
1489    struct tmpfs_dirent **pde)
1490{
1491	struct tmpfs_dir_cursor dc;
1492	struct tmpfs_dirent *de;
1493
1494	for (de = tmpfs_dir_first(tnp, &dc); de != NULL;
1495	     de = tmpfs_dir_next(tnp, &dc)) {
1496		if (de->td_node == tn) {
1497			*pde = de;
1498			return (0);
1499		}
1500	}
1501	return (ENOENT);
1502}
1503
1504static int
1505tmpfs_vptocnp_fill(struct vnode *vp, struct tmpfs_node *tn,
1506    struct tmpfs_node *tnp, char *buf, int *buflen, struct vnode **dvp)
1507{
1508	struct tmpfs_dirent *de;
1509	int error, i;
1510
1511	error = vn_vget_ino_gen(vp, tmpfs_vn_get_ino_alloc, tnp, LK_SHARED,
1512	    dvp);
1513	if (error != 0)
1514		return (error);
1515	error = tmpfs_vptocnp_dir(tn, tnp, &de);
1516	if (error == 0) {
1517		i = *buflen;
1518		i -= de->td_namelen;
1519		if (i < 0) {
1520			error = ENOMEM;
1521		} else {
1522			bcopy(de->ud.td_name, buf + i, de->td_namelen);
1523			*buflen = i;
1524		}
1525	}
1526	if (error == 0) {
1527		if (vp != *dvp)
1528			VOP_UNLOCK(*dvp, 0);
1529	} else {
1530		if (vp != *dvp)
1531			vput(*dvp);
1532		else
1533			vrele(vp);
1534	}
1535	return (error);
1536}
1537
1538static int
1539tmpfs_vptocnp(struct vop_vptocnp_args *ap)
1540{
1541	struct vnode *vp, **dvp;
1542	struct tmpfs_node *tn, *tnp, *tnp1;
1543	struct tmpfs_dirent *de;
1544	struct tmpfs_mount *tm;
1545	char *buf;
1546	int *buflen;
1547	int error;
1548
1549	vp = ap->a_vp;
1550	dvp = ap->a_vpp;
1551	buf = ap->a_buf;
1552	buflen = ap->a_buflen;
1553
1554	tm = VFS_TO_TMPFS(vp->v_mount);
1555	tn = VP_TO_TMPFS_NODE(vp);
1556	if (tn->tn_type == VDIR) {
1557		tnp = tn->tn_dir.tn_parent;
1558		if (tnp == NULL)
1559			return (ENOENT);
1560		tmpfs_ref_node(tnp);
1561		error = tmpfs_vptocnp_fill(vp, tn, tn->tn_dir.tn_parent, buf,
1562		    buflen, dvp);
1563		tmpfs_free_node(tm, tnp);
1564		return (error);
1565	}
1566restart:
1567	TMPFS_LOCK(tm);
1568restart_locked:
1569	LIST_FOREACH_SAFE(tnp, &tm->tm_nodes_used, tn_entries, tnp1) {
1570		if (tnp->tn_type != VDIR)
1571			continue;
1572		TMPFS_NODE_LOCK(tnp);
1573		tmpfs_ref_node_locked(tnp);
1574
1575		/*
1576		 * tn_vnode cannot be instantiated while we hold the
1577		 * node lock, so the directory cannot be changed while
1578		 * we iterate over it.  Do this to avoid instantiating
1579		 * vnode for directories which cannot point to our
1580		 * node.
1581		 */
1582		error = tnp->tn_vnode == NULL ? tmpfs_vptocnp_dir(tn, tnp,
1583		    &de) : 0;
1584
1585		if (error == 0) {
1586			TMPFS_NODE_UNLOCK(tnp);
1587			TMPFS_UNLOCK(tm);
1588			error = tmpfs_vptocnp_fill(vp, tn, tnp, buf, buflen,
1589			    dvp);
1590			if (error == 0) {
1591				tmpfs_free_node(tm, tnp);
1592				return (0);
1593			}
1594			if ((vp->v_iflag & VI_DOOMED) != 0) {
1595				tmpfs_free_node(tm, tnp);
1596				return (ENOENT);
1597			}
1598			TMPFS_LOCK(tm);
1599			TMPFS_NODE_LOCK(tnp);
1600		}
1601		if (tmpfs_free_node_locked(tm, tnp, false)) {
1602			goto restart;
1603		} else {
1604			KASSERT(tnp->tn_refcount > 0,
1605			    ("node %p refcount zero", tnp));
1606			if (tnp->tn_attached) {
1607				tnp1 = LIST_NEXT(tnp, tn_entries);
1608				TMPFS_NODE_UNLOCK(tnp);
1609			} else {
1610				TMPFS_NODE_UNLOCK(tnp);
1611				goto restart_locked;
1612			}
1613		}
1614	}
1615	TMPFS_UNLOCK(tm);
1616	return (ENOENT);
1617}
1618
1619/*
1620 * Vnode operations vector used for files stored in a tmpfs file system.
1621 */
1622struct vop_vector tmpfs_vnodeop_entries = {
1623	.vop_default =			&default_vnodeops,
1624	.vop_lookup =			vfs_cache_lookup,
1625	.vop_cachedlookup =		tmpfs_cached_lookup,
1626	.vop_create =			tmpfs_create,
1627	.vop_mknod =			tmpfs_mknod,
1628	.vop_open =			tmpfs_open,
1629	.vop_close =			tmpfs_close,
1630	.vop_access =			tmpfs_access,
1631	.vop_getattr =			tmpfs_getattr,
1632	.vop_setattr =			tmpfs_setattr,
1633	.vop_read =			tmpfs_read,
1634	.vop_write =			tmpfs_write,
1635	.vop_fsync =			tmpfs_fsync,
1636	.vop_remove =			tmpfs_remove,
1637	.vop_link =			tmpfs_link,
1638	.vop_rename =			tmpfs_rename,
1639	.vop_mkdir =			tmpfs_mkdir,
1640	.vop_rmdir =			tmpfs_rmdir,
1641	.vop_symlink =			tmpfs_symlink,
1642	.vop_readdir =			tmpfs_readdir,
1643	.vop_readlink =			tmpfs_readlink,
1644	.vop_inactive =			tmpfs_inactive,
1645	.vop_reclaim =			tmpfs_reclaim,
1646	.vop_print =			tmpfs_print,
1647	.vop_pathconf =			tmpfs_pathconf,
1648	.vop_vptofh =			tmpfs_vptofh,
1649	.vop_whiteout =			tmpfs_whiteout,
1650	.vop_bmap =			VOP_EOPNOTSUPP,
1651	.vop_vptocnp =			tmpfs_vptocnp,
1652};
1653
1654/*
1655 * Same vector for mounts which do not use namecache.
1656 */
1657struct vop_vector tmpfs_vnodeop_nonc_entries = {
1658	.vop_default =			&tmpfs_vnodeop_entries,
1659	.vop_lookup =			tmpfs_lookup,
1660};
1661