xref: /freebsd/sys/fs/tmpfs/tmpfs_vnops.c (revision db3cb3640f547c063293e9fdc4db69e9dc120951)
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) != 0)
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 	int error;
217 
218 	MPASS(vap->va_type == VREG || vap->va_type == VSOCK);
219 
220 	error = tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
221 	if (error == 0 && (cnp->cn_flags & MAKEENTRY) != 0)
222 		cache_enter(dvp, *vpp, cnp);
223 	return (error);
224 }
225 
226 static int
227 tmpfs_mknod(struct vop_mknod_args *v)
228 {
229 	struct vnode *dvp = v->a_dvp;
230 	struct vnode **vpp = v->a_vpp;
231 	struct componentname *cnp = v->a_cnp;
232 	struct vattr *vap = v->a_vap;
233 
234 	if (vap->va_type != VBLK && vap->va_type != VCHR &&
235 	    vap->va_type != VFIFO)
236 		return EINVAL;
237 
238 	return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
239 }
240 
241 static int
242 tmpfs_open(struct vop_open_args *v)
243 {
244 	struct vnode *vp = v->a_vp;
245 	int mode = v->a_mode;
246 
247 	int error;
248 	struct tmpfs_node *node;
249 
250 	MPASS(VOP_ISLOCKED(vp));
251 
252 	node = VP_TO_TMPFS_NODE(vp);
253 
254 	/* The file is still active but all its names have been removed
255 	 * (e.g. by a "rmdir $(pwd)").  It cannot be opened any more as
256 	 * it is about to die. */
257 	if (node->tn_links < 1)
258 		return (ENOENT);
259 
260 	/* If the file is marked append-only, deny write requests. */
261 	if (node->tn_flags & APPEND && (mode & (FWRITE | O_APPEND)) == FWRITE)
262 		error = EPERM;
263 	else {
264 		error = 0;
265 		/* For regular files, the call below is nop. */
266 		KASSERT(vp->v_type != VREG || (node->tn_reg.tn_aobj->flags &
267 		    OBJ_DEAD) == 0, ("dead object"));
268 		vnode_create_vobject(vp, node->tn_size, v->a_td);
269 	}
270 
271 	MPASS(VOP_ISLOCKED(vp));
272 	return error;
273 }
274 
275 static int
276 tmpfs_close(struct vop_close_args *v)
277 {
278 	struct vnode *vp = v->a_vp;
279 
280 	/* Update node times. */
281 	tmpfs_update(vp);
282 
283 	return (0);
284 }
285 
286 int
287 tmpfs_access(struct vop_access_args *v)
288 {
289 	struct vnode *vp = v->a_vp;
290 	accmode_t accmode = v->a_accmode;
291 	struct ucred *cred = v->a_cred;
292 
293 	int error;
294 	struct tmpfs_node *node;
295 
296 	MPASS(VOP_ISLOCKED(vp));
297 
298 	node = VP_TO_TMPFS_NODE(vp);
299 
300 	switch (vp->v_type) {
301 	case VDIR:
302 		/* FALLTHROUGH */
303 	case VLNK:
304 		/* FALLTHROUGH */
305 	case VREG:
306 		if (accmode & VWRITE && vp->v_mount->mnt_flag & MNT_RDONLY) {
307 			error = EROFS;
308 			goto out;
309 		}
310 		break;
311 
312 	case VBLK:
313 		/* FALLTHROUGH */
314 	case VCHR:
315 		/* FALLTHROUGH */
316 	case VSOCK:
317 		/* FALLTHROUGH */
318 	case VFIFO:
319 		break;
320 
321 	default:
322 		error = EINVAL;
323 		goto out;
324 	}
325 
326 	if (accmode & VWRITE && node->tn_flags & IMMUTABLE) {
327 		error = EPERM;
328 		goto out;
329 	}
330 
331 	error = vaccess(vp->v_type, node->tn_mode, node->tn_uid,
332 	    node->tn_gid, accmode, cred, NULL);
333 
334 out:
335 	MPASS(VOP_ISLOCKED(vp));
336 
337 	return error;
338 }
339 
340 int
341 tmpfs_getattr(struct vop_getattr_args *v)
342 {
343 	struct vnode *vp = v->a_vp;
344 	struct vattr *vap = v->a_vap;
345 
346 	struct tmpfs_node *node;
347 
348 	node = VP_TO_TMPFS_NODE(vp);
349 
350 	tmpfs_update(vp);
351 
352 	vap->va_type = vp->v_type;
353 	vap->va_mode = node->tn_mode;
354 	vap->va_nlink = node->tn_links;
355 	vap->va_uid = node->tn_uid;
356 	vap->va_gid = node->tn_gid;
357 	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
358 	vap->va_fileid = node->tn_id;
359 	vap->va_size = node->tn_size;
360 	vap->va_blocksize = PAGE_SIZE;
361 	vap->va_atime = node->tn_atime;
362 	vap->va_mtime = node->tn_mtime;
363 	vap->va_ctime = node->tn_ctime;
364 	vap->va_birthtime = node->tn_birthtime;
365 	vap->va_gen = node->tn_gen;
366 	vap->va_flags = node->tn_flags;
367 	vap->va_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ?
368 		node->tn_rdev : NODEV;
369 	vap->va_bytes = round_page(node->tn_size);
370 	vap->va_filerev = 0;
371 
372 	return 0;
373 }
374 
375 int
376 tmpfs_setattr(struct vop_setattr_args *v)
377 {
378 	struct vnode *vp = v->a_vp;
379 	struct vattr *vap = v->a_vap;
380 	struct ucred *cred = v->a_cred;
381 	struct thread *td = curthread;
382 
383 	int error;
384 
385 	MPASS(VOP_ISLOCKED(vp));
386 
387 	error = 0;
388 
389 	/* Abort if any unsettable attribute is given. */
390 	if (vap->va_type != VNON ||
391 	    vap->va_nlink != VNOVAL ||
392 	    vap->va_fsid != VNOVAL ||
393 	    vap->va_fileid != VNOVAL ||
394 	    vap->va_blocksize != VNOVAL ||
395 	    vap->va_gen != VNOVAL ||
396 	    vap->va_rdev != VNOVAL ||
397 	    vap->va_bytes != VNOVAL)
398 		error = EINVAL;
399 
400 	if (error == 0 && (vap->va_flags != VNOVAL))
401 		error = tmpfs_chflags(vp, vap->va_flags, cred, td);
402 
403 	if (error == 0 && (vap->va_size != VNOVAL))
404 		error = tmpfs_chsize(vp, vap->va_size, cred, td);
405 
406 	if (error == 0 && (vap->va_uid != VNOVAL || vap->va_gid != VNOVAL))
407 		error = tmpfs_chown(vp, vap->va_uid, vap->va_gid, cred, td);
408 
409 	if (error == 0 && (vap->va_mode != (mode_t)VNOVAL))
410 		error = tmpfs_chmod(vp, vap->va_mode, cred, td);
411 
412 	if (error == 0 && ((vap->va_atime.tv_sec != VNOVAL &&
413 	    vap->va_atime.tv_nsec != VNOVAL) ||
414 	    (vap->va_mtime.tv_sec != VNOVAL &&
415 	    vap->va_mtime.tv_nsec != VNOVAL) ||
416 	    (vap->va_birthtime.tv_sec != VNOVAL &&
417 	    vap->va_birthtime.tv_nsec != VNOVAL)))
418 		error = tmpfs_chtimes(vp, vap, cred, td);
419 
420 	/* Update the node times.  We give preference to the error codes
421 	 * generated by this function rather than the ones that may arise
422 	 * from tmpfs_update. */
423 	tmpfs_update(vp);
424 
425 	MPASS(VOP_ISLOCKED(vp));
426 
427 	return error;
428 }
429 
430 static int
431 tmpfs_read(struct vop_read_args *v)
432 {
433 	struct vnode *vp;
434 	struct uio *uio;
435 	struct tmpfs_node *node;
436 
437 	vp = v->a_vp;
438 	if (vp->v_type != VREG)
439 		return (EISDIR);
440 	uio = v->a_uio;
441 	if (uio->uio_offset < 0)
442 		return (EINVAL);
443 	node = VP_TO_TMPFS_NODE(vp);
444 	node->tn_status |= TMPFS_NODE_ACCESSED;
445 	return (uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio));
446 }
447 
448 static int
449 tmpfs_write(struct vop_write_args *v)
450 {
451 	struct vnode *vp;
452 	struct uio *uio;
453 	struct tmpfs_node *node;
454 	off_t oldsize;
455 	int error, ioflag;
456 	boolean_t extended;
457 
458 	vp = v->a_vp;
459 	uio = v->a_uio;
460 	ioflag = v->a_ioflag;
461 	error = 0;
462 	node = VP_TO_TMPFS_NODE(vp);
463 	oldsize = node->tn_size;
464 
465 	if (uio->uio_offset < 0 || vp->v_type != VREG)
466 		return (EINVAL);
467 	if (uio->uio_resid == 0)
468 		return (0);
469 	if (ioflag & IO_APPEND)
470 		uio->uio_offset = node->tn_size;
471 	if (uio->uio_offset + uio->uio_resid >
472 	  VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize)
473 		return (EFBIG);
474 	if (vn_rlimit_fsize(vp, uio, uio->uio_td))
475 		return (EFBIG);
476 	extended = uio->uio_offset + uio->uio_resid > node->tn_size;
477 	if (extended) {
478 		error = tmpfs_reg_resize(vp, uio->uio_offset + uio->uio_resid,
479 		    FALSE);
480 		if (error != 0)
481 			goto out;
482 	}
483 
484 	error = uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio);
485 	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED |
486 	    (extended ? TMPFS_NODE_CHANGED : 0);
487 	if (node->tn_mode & (S_ISUID | S_ISGID)) {
488 		if (priv_check_cred(v->a_cred, PRIV_VFS_RETAINSUGID, 0))
489 			node->tn_mode &= ~(S_ISUID | S_ISGID);
490 	}
491 	if (error != 0)
492 		(void)tmpfs_reg_resize(vp, oldsize, TRUE);
493 
494 out:
495 	MPASS(IMPLIES(error == 0, uio->uio_resid == 0));
496 	MPASS(IMPLIES(error != 0, oldsize == node->tn_size));
497 
498 	return (error);
499 }
500 
501 static int
502 tmpfs_fsync(struct vop_fsync_args *v)
503 {
504 	struct vnode *vp = v->a_vp;
505 
506 	MPASS(VOP_ISLOCKED(vp));
507 
508 	tmpfs_update(vp);
509 
510 	return 0;
511 }
512 
513 static int
514 tmpfs_remove(struct vop_remove_args *v)
515 {
516 	struct vnode *dvp = v->a_dvp;
517 	struct vnode *vp = v->a_vp;
518 
519 	int error;
520 	struct tmpfs_dirent *de;
521 	struct tmpfs_mount *tmp;
522 	struct tmpfs_node *dnode;
523 	struct tmpfs_node *node;
524 
525 	MPASS(VOP_ISLOCKED(dvp));
526 	MPASS(VOP_ISLOCKED(vp));
527 
528 	if (vp->v_type == VDIR) {
529 		error = EISDIR;
530 		goto out;
531 	}
532 
533 	dnode = VP_TO_TMPFS_DIR(dvp);
534 	node = VP_TO_TMPFS_NODE(vp);
535 	tmp = VFS_TO_TMPFS(vp->v_mount);
536 	de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
537 	MPASS(de != NULL);
538 
539 	/* Files marked as immutable or append-only cannot be deleted. */
540 	if ((node->tn_flags & (IMMUTABLE | APPEND | NOUNLINK)) ||
541 	    (dnode->tn_flags & APPEND)) {
542 		error = EPERM;
543 		goto out;
544 	}
545 
546 	/* Remove the entry from the directory; as it is a file, we do not
547 	 * have to change the number of hard links of the directory. */
548 	tmpfs_dir_detach(dvp, de);
549 	if (v->a_cnp->cn_flags & DOWHITEOUT)
550 		tmpfs_dir_whiteout_add(dvp, v->a_cnp);
551 
552 	/* Free the directory entry we just deleted.  Note that the node
553 	 * referred by it will not be removed until the vnode is really
554 	 * reclaimed. */
555 	tmpfs_free_dirent(tmp, de);
556 
557 	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED;
558 	error = 0;
559 
560 out:
561 
562 	return error;
563 }
564 
565 static int
566 tmpfs_link(struct vop_link_args *v)
567 {
568 	struct vnode *dvp = v->a_tdvp;
569 	struct vnode *vp = v->a_vp;
570 	struct componentname *cnp = v->a_cnp;
571 
572 	int error;
573 	struct tmpfs_dirent *de;
574 	struct tmpfs_node *node;
575 
576 	MPASS(VOP_ISLOCKED(dvp));
577 	MPASS(cnp->cn_flags & HASBUF);
578 	MPASS(dvp != vp); /* XXX When can this be false? */
579 	node = VP_TO_TMPFS_NODE(vp);
580 
581 	/* Ensure that we do not overflow the maximum number of links imposed
582 	 * by the system. */
583 	MPASS(node->tn_links <= LINK_MAX);
584 	if (node->tn_links == LINK_MAX) {
585 		error = EMLINK;
586 		goto out;
587 	}
588 
589 	/* We cannot create links of files marked immutable or append-only. */
590 	if (node->tn_flags & (IMMUTABLE | APPEND)) {
591 		error = EPERM;
592 		goto out;
593 	}
594 
595 	/* Allocate a new directory entry to represent the node. */
596 	error = tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount), node,
597 	    cnp->cn_nameptr, cnp->cn_namelen, &de);
598 	if (error != 0)
599 		goto out;
600 
601 	/* Insert the new directory entry into the appropriate directory. */
602 	if (cnp->cn_flags & ISWHITEOUT)
603 		tmpfs_dir_whiteout_remove(dvp, cnp);
604 	tmpfs_dir_attach(dvp, de);
605 
606 	/* vp link count has changed, so update node times. */
607 	node->tn_status |= TMPFS_NODE_CHANGED;
608 	tmpfs_update(vp);
609 
610 	error = 0;
611 
612 out:
613 	return error;
614 }
615 
616 /*
617  * We acquire all but fdvp locks using non-blocking acquisitions.  If we
618  * fail to acquire any lock in the path we will drop all held locks,
619  * acquire the new lock in a blocking fashion, and then release it and
620  * restart the rename.  This acquire/release step ensures that we do not
621  * spin on a lock waiting for release.  On error release all vnode locks
622  * and decrement references the way tmpfs_rename() would do.
623  */
624 static int
625 tmpfs_rename_relock(struct vnode *fdvp, struct vnode **fvpp,
626     struct vnode *tdvp, struct vnode **tvpp,
627     struct componentname *fcnp, struct componentname *tcnp)
628 {
629 	struct vnode *nvp;
630 	struct mount *mp;
631 	struct tmpfs_dirent *de;
632 	int error, restarts = 0;
633 
634 	VOP_UNLOCK(tdvp, 0);
635 	if (*tvpp != NULL && *tvpp != tdvp)
636 		VOP_UNLOCK(*tvpp, 0);
637 	mp = fdvp->v_mount;
638 
639 relock:
640 	restarts += 1;
641 	error = vn_lock(fdvp, LK_EXCLUSIVE);
642 	if (error)
643 		goto releout;
644 	if (vn_lock(tdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
645 		VOP_UNLOCK(fdvp, 0);
646 		error = vn_lock(tdvp, LK_EXCLUSIVE);
647 		if (error)
648 			goto releout;
649 		VOP_UNLOCK(tdvp, 0);
650 		goto relock;
651 	}
652 	/*
653 	 * Re-resolve fvp to be certain it still exists and fetch the
654 	 * correct vnode.
655 	 */
656 	de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(fdvp), NULL, fcnp);
657 	if (de == NULL) {
658 		VOP_UNLOCK(fdvp, 0);
659 		VOP_UNLOCK(tdvp, 0);
660 		if ((fcnp->cn_flags & ISDOTDOT) != 0 ||
661 		    (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.'))
662 			error = EINVAL;
663 		else
664 			error = ENOENT;
665 		goto releout;
666 	}
667 	error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp);
668 	if (error != 0) {
669 		VOP_UNLOCK(fdvp, 0);
670 		VOP_UNLOCK(tdvp, 0);
671 		if (error != EBUSY)
672 			goto releout;
673 		error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp);
674 		if (error != 0)
675 			goto releout;
676 		VOP_UNLOCK(nvp, 0);
677 		/*
678 		 * Concurrent rename race.
679 		 */
680 		if (nvp == tdvp) {
681 			vrele(nvp);
682 			error = EINVAL;
683 			goto releout;
684 		}
685 		vrele(*fvpp);
686 		*fvpp = nvp;
687 		goto relock;
688 	}
689 	vrele(*fvpp);
690 	*fvpp = nvp;
691 	VOP_UNLOCK(*fvpp, 0);
692 	/*
693 	 * Re-resolve tvp and acquire the vnode lock if present.
694 	 */
695 	de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(tdvp), NULL, tcnp);
696 	/*
697 	 * If tvp disappeared we just carry on.
698 	 */
699 	if (de == NULL && *tvpp != NULL) {
700 		vrele(*tvpp);
701 		*tvpp = NULL;
702 	}
703 	/*
704 	 * Get the tvp ino if the lookup succeeded.  We may have to restart
705 	 * if the non-blocking acquire fails.
706 	 */
707 	if (de != NULL) {
708 		nvp = NULL;
709 		error = tmpfs_alloc_vp(mp, de->td_node,
710 		    LK_EXCLUSIVE | LK_NOWAIT, &nvp);
711 		if (*tvpp != NULL)
712 			vrele(*tvpp);
713 		*tvpp = nvp;
714 		if (error != 0) {
715 			VOP_UNLOCK(fdvp, 0);
716 			VOP_UNLOCK(tdvp, 0);
717 			if (error != EBUSY)
718 				goto releout;
719 			error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE,
720 			    &nvp);
721 			if (error != 0)
722 				goto releout;
723 			VOP_UNLOCK(nvp, 0);
724 			/*
725 			 * fdvp contains fvp, thus tvp (=fdvp) is not empty.
726 			 */
727 			if (nvp == fdvp) {
728 				error = ENOTEMPTY;
729 				goto releout;
730 			}
731 			goto relock;
732 		}
733 	}
734 	tmpfs_rename_restarts += restarts;
735 
736 	return (0);
737 
738 releout:
739 	vrele(fdvp);
740 	vrele(*fvpp);
741 	vrele(tdvp);
742 	if (*tvpp != NULL)
743 		vrele(*tvpp);
744 	tmpfs_rename_restarts += restarts;
745 
746 	return (error);
747 }
748 
749 static int
750 tmpfs_rename(struct vop_rename_args *v)
751 {
752 	struct vnode *fdvp = v->a_fdvp;
753 	struct vnode *fvp = v->a_fvp;
754 	struct componentname *fcnp = v->a_fcnp;
755 	struct vnode *tdvp = v->a_tdvp;
756 	struct vnode *tvp = v->a_tvp;
757 	struct componentname *tcnp = v->a_tcnp;
758 	struct mount *mp = NULL;
759 
760 	char *newname;
761 	int error;
762 	struct tmpfs_dirent *de;
763 	struct tmpfs_mount *tmp;
764 	struct tmpfs_node *fdnode;
765 	struct tmpfs_node *fnode;
766 	struct tmpfs_node *tnode;
767 	struct tmpfs_node *tdnode;
768 
769 	MPASS(VOP_ISLOCKED(tdvp));
770 	MPASS(IMPLIES(tvp != NULL, VOP_ISLOCKED(tvp)));
771 	MPASS(fcnp->cn_flags & HASBUF);
772 	MPASS(tcnp->cn_flags & HASBUF);
773 
774 	/* Disallow cross-device renames.
775 	 * XXX Why isn't this done by the caller? */
776 	if (fvp->v_mount != tdvp->v_mount ||
777 	    (tvp != NULL && fvp->v_mount != tvp->v_mount)) {
778 		error = EXDEV;
779 		goto out;
780 	}
781 
782 	/* If source and target are the same file, there is nothing to do. */
783 	if (fvp == tvp) {
784 		error = 0;
785 		goto out;
786 	}
787 
788 	/* If we need to move the directory between entries, lock the
789 	 * source so that we can safely operate on it. */
790 	if (fdvp != tdvp && fdvp != tvp) {
791 		if (vn_lock(fdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
792 			mp = tdvp->v_mount;
793 			error = vfs_busy(mp, 0);
794 			if (error != 0) {
795 				mp = NULL;
796 				goto out;
797 			}
798 			error = tmpfs_rename_relock(fdvp, &fvp, tdvp, &tvp,
799 			    fcnp, tcnp);
800 			if (error != 0) {
801 				vfs_unbusy(mp);
802 				return (error);
803 			}
804 			ASSERT_VOP_ELOCKED(fdvp,
805 			    "tmpfs_rename: fdvp not locked");
806 			ASSERT_VOP_ELOCKED(tdvp,
807 			    "tmpfs_rename: tdvp not locked");
808 			if (tvp != NULL)
809 				ASSERT_VOP_ELOCKED(tvp,
810 				    "tmpfs_rename: tvp not locked");
811 			if (fvp == tvp) {
812 				error = 0;
813 				goto out_locked;
814 			}
815 		}
816 	}
817 
818 	tmp = VFS_TO_TMPFS(tdvp->v_mount);
819 	tdnode = VP_TO_TMPFS_DIR(tdvp);
820 	tnode = (tvp == NULL) ? NULL : VP_TO_TMPFS_NODE(tvp);
821 	fdnode = VP_TO_TMPFS_DIR(fdvp);
822 	fnode = VP_TO_TMPFS_NODE(fvp);
823 	de = tmpfs_dir_lookup(fdnode, fnode, fcnp);
824 
825 	/* Entry can disappear before we lock fdvp,
826 	 * also avoid manipulating '.' and '..' entries. */
827 	if (de == NULL) {
828 		if ((fcnp->cn_flags & ISDOTDOT) != 0 ||
829 		    (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.'))
830 			error = EINVAL;
831 		else
832 			error = ENOENT;
833 		goto out_locked;
834 	}
835 	MPASS(de->td_node == fnode);
836 
837 	/* If re-naming a directory to another preexisting directory
838 	 * ensure that the target directory is empty so that its
839 	 * removal causes no side effects.
840 	 * Kern_rename gurantees the destination to be a directory
841 	 * if the source is one. */
842 	if (tvp != NULL) {
843 		MPASS(tnode != NULL);
844 
845 		if ((tnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
846 		    (tdnode->tn_flags & (APPEND | IMMUTABLE))) {
847 			error = EPERM;
848 			goto out_locked;
849 		}
850 
851 		if (fnode->tn_type == VDIR && tnode->tn_type == VDIR) {
852 			if (tnode->tn_size > 0) {
853 				error = ENOTEMPTY;
854 				goto out_locked;
855 			}
856 		} else if (fnode->tn_type == VDIR && tnode->tn_type != VDIR) {
857 			error = ENOTDIR;
858 			goto out_locked;
859 		} else if (fnode->tn_type != VDIR && tnode->tn_type == VDIR) {
860 			error = EISDIR;
861 			goto out_locked;
862 		} else {
863 			MPASS(fnode->tn_type != VDIR &&
864 				tnode->tn_type != VDIR);
865 		}
866 	}
867 
868 	if ((fnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))
869 	    || (fdnode->tn_flags & (APPEND | IMMUTABLE))) {
870 		error = EPERM;
871 		goto out_locked;
872 	}
873 
874 	/* Ensure that we have enough memory to hold the new name, if it
875 	 * has to be changed. */
876 	if (fcnp->cn_namelen != tcnp->cn_namelen ||
877 	    bcmp(fcnp->cn_nameptr, tcnp->cn_nameptr, fcnp->cn_namelen) != 0) {
878 		newname = malloc(tcnp->cn_namelen, M_TMPFSNAME, M_WAITOK);
879 	} else
880 		newname = NULL;
881 
882 	/* If the node is being moved to another directory, we have to do
883 	 * the move. */
884 	if (fdnode != tdnode) {
885 		/* In case we are moving a directory, we have to adjust its
886 		 * parent to point to the new parent. */
887 		if (de->td_node->tn_type == VDIR) {
888 			struct tmpfs_node *n;
889 
890 			/* Ensure the target directory is not a child of the
891 			 * directory being moved.  Otherwise, we'd end up
892 			 * with stale nodes. */
893 			n = tdnode;
894 			/* TMPFS_LOCK garanties that no nodes are freed while
895 			 * traversing the list. Nodes can only be marked as
896 			 * removed: tn_parent == NULL. */
897 			TMPFS_LOCK(tmp);
898 			TMPFS_NODE_LOCK(n);
899 			while (n != n->tn_dir.tn_parent) {
900 				struct tmpfs_node *parent;
901 
902 				if (n == fnode) {
903 					TMPFS_NODE_UNLOCK(n);
904 					TMPFS_UNLOCK(tmp);
905 					error = EINVAL;
906 					if (newname != NULL)
907 						    free(newname, M_TMPFSNAME);
908 					goto out_locked;
909 				}
910 				parent = n->tn_dir.tn_parent;
911 				TMPFS_NODE_UNLOCK(n);
912 				if (parent == NULL) {
913 					n = NULL;
914 					break;
915 				}
916 				TMPFS_NODE_LOCK(parent);
917 				if (parent->tn_dir.tn_parent == NULL) {
918 					TMPFS_NODE_UNLOCK(parent);
919 					n = NULL;
920 					break;
921 				}
922 				n = parent;
923 			}
924 			TMPFS_UNLOCK(tmp);
925 			if (n == NULL) {
926 				error = EINVAL;
927 				if (newname != NULL)
928 					    free(newname, M_TMPFSNAME);
929 				goto out_locked;
930 			}
931 			TMPFS_NODE_UNLOCK(n);
932 
933 			/* Adjust the parent pointer. */
934 			TMPFS_VALIDATE_DIR(fnode);
935 			TMPFS_NODE_LOCK(de->td_node);
936 			de->td_node->tn_dir.tn_parent = tdnode;
937 			TMPFS_NODE_UNLOCK(de->td_node);
938 
939 			/* As a result of changing the target of the '..'
940 			 * entry, the link count of the source and target
941 			 * directories has to be adjusted. */
942 			TMPFS_NODE_LOCK(tdnode);
943 			TMPFS_ASSERT_LOCKED(tdnode);
944 			tdnode->tn_links++;
945 			TMPFS_NODE_UNLOCK(tdnode);
946 
947 			TMPFS_NODE_LOCK(fdnode);
948 			TMPFS_ASSERT_LOCKED(fdnode);
949 			fdnode->tn_links--;
950 			TMPFS_NODE_UNLOCK(fdnode);
951 		}
952 	}
953 
954 	/* Do the move: just remove the entry from the source directory
955 	 * and insert it into the target one. */
956 	tmpfs_dir_detach(fdvp, de);
957 
958 	if (fcnp->cn_flags & DOWHITEOUT)
959 		tmpfs_dir_whiteout_add(fdvp, fcnp);
960 	if (tcnp->cn_flags & ISWHITEOUT)
961 		tmpfs_dir_whiteout_remove(tdvp, tcnp);
962 
963 	/* If the name has changed, we need to make it effective by changing
964 	 * it in the directory entry. */
965 	if (newname != NULL) {
966 		MPASS(tcnp->cn_namelen <= MAXNAMLEN);
967 
968 		free(de->ud.td_name, M_TMPFSNAME);
969 		de->ud.td_name = newname;
970 		tmpfs_dirent_init(de, tcnp->cn_nameptr, tcnp->cn_namelen);
971 
972 		fnode->tn_status |= TMPFS_NODE_CHANGED;
973 		tdnode->tn_status |= TMPFS_NODE_MODIFIED;
974 	}
975 
976 	/* If we are overwriting an entry, we have to remove the old one
977 	 * from the target directory. */
978 	if (tvp != NULL) {
979 		struct tmpfs_dirent *tde;
980 
981 		/* Remove the old entry from the target directory. */
982 		tde = tmpfs_dir_lookup(tdnode, tnode, tcnp);
983 		tmpfs_dir_detach(tdvp, tde);
984 
985 		/* Free the directory entry we just deleted.  Note that the
986 		 * node referred by it will not be removed until the vnode is
987 		 * really reclaimed. */
988 		tmpfs_free_dirent(VFS_TO_TMPFS(tvp->v_mount), tde);
989 	}
990 
991 	tmpfs_dir_attach(tdvp, de);
992 
993 	cache_purge(fvp);
994 	if (tvp != NULL)
995 		cache_purge(tvp);
996 	cache_purge_negative(tdvp);
997 
998 	error = 0;
999 
1000 out_locked:
1001 	if (fdvp != tdvp && fdvp != tvp)
1002 		VOP_UNLOCK(fdvp, 0);
1003 
1004 out:
1005 	/* Release target nodes. */
1006 	/* XXX: I don't understand when tdvp can be the same as tvp, but
1007 	 * other code takes care of this... */
1008 	if (tdvp == tvp)
1009 		vrele(tdvp);
1010 	else
1011 		vput(tdvp);
1012 	if (tvp != NULL)
1013 		vput(tvp);
1014 
1015 	/* Release source nodes. */
1016 	vrele(fdvp);
1017 	vrele(fvp);
1018 
1019 	if (mp != NULL)
1020 		vfs_unbusy(mp);
1021 
1022 	return error;
1023 }
1024 
1025 static int
1026 tmpfs_mkdir(struct vop_mkdir_args *v)
1027 {
1028 	struct vnode *dvp = v->a_dvp;
1029 	struct vnode **vpp = v->a_vpp;
1030 	struct componentname *cnp = v->a_cnp;
1031 	struct vattr *vap = v->a_vap;
1032 
1033 	MPASS(vap->va_type == VDIR);
1034 
1035 	return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
1036 }
1037 
1038 static int
1039 tmpfs_rmdir(struct vop_rmdir_args *v)
1040 {
1041 	struct vnode *dvp = v->a_dvp;
1042 	struct vnode *vp = v->a_vp;
1043 
1044 	int error;
1045 	struct tmpfs_dirent *de;
1046 	struct tmpfs_mount *tmp;
1047 	struct tmpfs_node *dnode;
1048 	struct tmpfs_node *node;
1049 
1050 	MPASS(VOP_ISLOCKED(dvp));
1051 	MPASS(VOP_ISLOCKED(vp));
1052 
1053 	tmp = VFS_TO_TMPFS(dvp->v_mount);
1054 	dnode = VP_TO_TMPFS_DIR(dvp);
1055 	node = VP_TO_TMPFS_DIR(vp);
1056 
1057 	/* Directories with more than two entries ('.' and '..') cannot be
1058 	 * removed. */
1059 	 if (node->tn_size > 0) {
1060 		 error = ENOTEMPTY;
1061 		 goto out;
1062 	 }
1063 
1064 	if ((dnode->tn_flags & APPEND)
1065 	    || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
1066 		error = EPERM;
1067 		goto out;
1068 	}
1069 
1070 	/* This invariant holds only if we are not trying to remove "..".
1071 	  * We checked for that above so this is safe now. */
1072 	MPASS(node->tn_dir.tn_parent == dnode);
1073 
1074 	/* Get the directory entry associated with node (vp).  This was
1075 	 * filled by tmpfs_lookup while looking up the entry. */
1076 	de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
1077 	MPASS(TMPFS_DIRENT_MATCHES(de,
1078 	    v->a_cnp->cn_nameptr,
1079 	    v->a_cnp->cn_namelen));
1080 
1081 	/* Check flags to see if we are allowed to remove the directory. */
1082 	if (dnode->tn_flags & APPEND
1083 		|| node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) {
1084 		error = EPERM;
1085 		goto out;
1086 	}
1087 
1088 
1089 	/* Detach the directory entry from the directory (dnode). */
1090 	tmpfs_dir_detach(dvp, de);
1091 	if (v->a_cnp->cn_flags & DOWHITEOUT)
1092 		tmpfs_dir_whiteout_add(dvp, v->a_cnp);
1093 
1094 	/* No vnode should be allocated for this entry from this point */
1095 	TMPFS_NODE_LOCK(node);
1096 	TMPFS_ASSERT_ELOCKED(node);
1097 	node->tn_links--;
1098 	node->tn_dir.tn_parent = NULL;
1099 	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | \
1100 	    TMPFS_NODE_MODIFIED;
1101 
1102 	TMPFS_NODE_UNLOCK(node);
1103 
1104 	TMPFS_NODE_LOCK(dnode);
1105 	TMPFS_ASSERT_ELOCKED(dnode);
1106 	dnode->tn_links--;
1107 	dnode->tn_status |= TMPFS_NODE_ACCESSED | \
1108 	    TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED;
1109 	TMPFS_NODE_UNLOCK(dnode);
1110 
1111 	cache_purge(dvp);
1112 	cache_purge(vp);
1113 
1114 	/* Free the directory entry we just deleted.  Note that the node
1115 	 * referred by it will not be removed until the vnode is really
1116 	 * reclaimed. */
1117 	tmpfs_free_dirent(tmp, de);
1118 
1119 	/* Release the deleted vnode (will destroy the node, notify
1120 	 * interested parties and clean it from the cache). */
1121 
1122 	dnode->tn_status |= TMPFS_NODE_CHANGED;
1123 	tmpfs_update(dvp);
1124 
1125 	error = 0;
1126 
1127 out:
1128 	return error;
1129 }
1130 
1131 static int
1132 tmpfs_symlink(struct vop_symlink_args *v)
1133 {
1134 	struct vnode *dvp = v->a_dvp;
1135 	struct vnode **vpp = v->a_vpp;
1136 	struct componentname *cnp = v->a_cnp;
1137 	struct vattr *vap = v->a_vap;
1138 	char *target = v->a_target;
1139 
1140 #ifdef notyet /* XXX FreeBSD BUG: kern_symlink is not setting VLNK */
1141 	MPASS(vap->va_type == VLNK);
1142 #else
1143 	vap->va_type = VLNK;
1144 #endif
1145 
1146 	return tmpfs_alloc_file(dvp, vpp, vap, cnp, target);
1147 }
1148 
1149 static int
1150 tmpfs_readdir(struct vop_readdir_args *v)
1151 {
1152 	struct vnode *vp = v->a_vp;
1153 	struct uio *uio = v->a_uio;
1154 	int *eofflag = v->a_eofflag;
1155 	u_long **cookies = v->a_cookies;
1156 	int *ncookies = v->a_ncookies;
1157 
1158 	int error;
1159 	ssize_t startresid;
1160 	int maxcookies;
1161 	struct tmpfs_node *node;
1162 
1163 	/* This operation only makes sense on directory nodes. */
1164 	if (vp->v_type != VDIR)
1165 		return ENOTDIR;
1166 
1167 	maxcookies = 0;
1168 	node = VP_TO_TMPFS_DIR(vp);
1169 
1170 	startresid = uio->uio_resid;
1171 
1172 	/* Allocate cookies for NFS and compat modules. */
1173 	if (cookies != NULL && ncookies != NULL) {
1174 		maxcookies = howmany(node->tn_size,
1175 		    sizeof(struct tmpfs_dirent)) + 2;
1176 		*cookies = malloc(maxcookies * sizeof(**cookies), M_TEMP,
1177 		    M_WAITOK);
1178 		*ncookies = 0;
1179 	}
1180 
1181 	if (cookies == NULL)
1182 		error = tmpfs_dir_getdents(node, uio, 0, NULL, NULL);
1183 	else
1184 		error = tmpfs_dir_getdents(node, uio, maxcookies, *cookies,
1185 		    ncookies);
1186 
1187 	/* Buffer was filled without hitting EOF. */
1188 	if (error == EJUSTRETURN)
1189 		error = (uio->uio_resid != startresid) ? 0 : EINVAL;
1190 
1191 	if (error != 0 && cookies != NULL)
1192 		free(*cookies, M_TEMP);
1193 
1194 	if (eofflag != NULL)
1195 		*eofflag =
1196 		    (error == 0 && uio->uio_offset == TMPFS_DIRCOOKIE_EOF);
1197 
1198 	return error;
1199 }
1200 
1201 static int
1202 tmpfs_readlink(struct vop_readlink_args *v)
1203 {
1204 	struct vnode *vp = v->a_vp;
1205 	struct uio *uio = v->a_uio;
1206 
1207 	int error;
1208 	struct tmpfs_node *node;
1209 
1210 	MPASS(uio->uio_offset == 0);
1211 	MPASS(vp->v_type == VLNK);
1212 
1213 	node = VP_TO_TMPFS_NODE(vp);
1214 
1215 	error = uiomove(node->tn_link, MIN(node->tn_size, uio->uio_resid),
1216 	    uio);
1217 	node->tn_status |= TMPFS_NODE_ACCESSED;
1218 
1219 	return error;
1220 }
1221 
1222 static int
1223 tmpfs_inactive(struct vop_inactive_args *v)
1224 {
1225 	struct vnode *vp = v->a_vp;
1226 
1227 	struct tmpfs_node *node;
1228 
1229 	node = VP_TO_TMPFS_NODE(vp);
1230 
1231 	if (node->tn_links == 0)
1232 		vrecycle(vp);
1233 
1234 	return 0;
1235 }
1236 
1237 int
1238 tmpfs_reclaim(struct vop_reclaim_args *v)
1239 {
1240 	struct vnode *vp = v->a_vp;
1241 
1242 	struct tmpfs_mount *tmp;
1243 	struct tmpfs_node *node;
1244 
1245 	node = VP_TO_TMPFS_NODE(vp);
1246 	tmp = VFS_TO_TMPFS(vp->v_mount);
1247 
1248 	if (vp->v_type == VREG)
1249 		tmpfs_destroy_vobject(vp, node->tn_reg.tn_aobj);
1250 	else
1251 		vnode_destroy_vobject(vp);
1252 	vp->v_object = NULL;
1253 	cache_purge(vp);
1254 
1255 	TMPFS_NODE_LOCK(node);
1256 	TMPFS_ASSERT_ELOCKED(node);
1257 	tmpfs_free_vp(vp);
1258 
1259 	/* If the node referenced by this vnode was deleted by the user,
1260 	 * we must free its associated data structures (now that the vnode
1261 	 * is being reclaimed). */
1262 	if (node->tn_links == 0 &&
1263 	    (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) {
1264 		node->tn_vpstate = TMPFS_VNODE_DOOMED;
1265 		TMPFS_NODE_UNLOCK(node);
1266 		tmpfs_free_node(tmp, node);
1267 	} else
1268 		TMPFS_NODE_UNLOCK(node);
1269 
1270 	MPASS(vp->v_data == NULL);
1271 	return 0;
1272 }
1273 
1274 static int
1275 tmpfs_print(struct vop_print_args *v)
1276 {
1277 	struct vnode *vp = v->a_vp;
1278 
1279 	struct tmpfs_node *node;
1280 
1281 	node = VP_TO_TMPFS_NODE(vp);
1282 
1283 	printf("tag VT_TMPFS, tmpfs_node %p, flags 0x%lx, links %d\n",
1284 	    node, node->tn_flags, node->tn_links);
1285 	printf("\tmode 0%o, owner %d, group %d, size %jd, status 0x%x\n",
1286 	    node->tn_mode, node->tn_uid, node->tn_gid,
1287 	    (intmax_t)node->tn_size, node->tn_status);
1288 
1289 	if (vp->v_type == VFIFO)
1290 		fifo_printinfo(vp);
1291 
1292 	printf("\n");
1293 
1294 	return 0;
1295 }
1296 
1297 static int
1298 tmpfs_pathconf(struct vop_pathconf_args *v)
1299 {
1300 	int name = v->a_name;
1301 	register_t *retval = v->a_retval;
1302 
1303 	int error;
1304 
1305 	error = 0;
1306 
1307 	switch (name) {
1308 	case _PC_LINK_MAX:
1309 		*retval = LINK_MAX;
1310 		break;
1311 
1312 	case _PC_NAME_MAX:
1313 		*retval = NAME_MAX;
1314 		break;
1315 
1316 	case _PC_PATH_MAX:
1317 		*retval = PATH_MAX;
1318 		break;
1319 
1320 	case _PC_PIPE_BUF:
1321 		*retval = PIPE_BUF;
1322 		break;
1323 
1324 	case _PC_CHOWN_RESTRICTED:
1325 		*retval = 1;
1326 		break;
1327 
1328 	case _PC_NO_TRUNC:
1329 		*retval = 1;
1330 		break;
1331 
1332 	case _PC_SYNC_IO:
1333 		*retval = 1;
1334 		break;
1335 
1336 	case _PC_FILESIZEBITS:
1337 		*retval = 0; /* XXX Don't know which value should I return. */
1338 		break;
1339 
1340 	default:
1341 		error = EINVAL;
1342 	}
1343 
1344 	return error;
1345 }
1346 
1347 static int
1348 tmpfs_vptofh(struct vop_vptofh_args *ap)
1349 {
1350 	struct tmpfs_fid *tfhp;
1351 	struct tmpfs_node *node;
1352 
1353 	tfhp = (struct tmpfs_fid *)ap->a_fhp;
1354 	node = VP_TO_TMPFS_NODE(ap->a_vp);
1355 
1356 	tfhp->tf_len = sizeof(struct tmpfs_fid);
1357 	tfhp->tf_id = node->tn_id;
1358 	tfhp->tf_gen = node->tn_gen;
1359 
1360 	return (0);
1361 }
1362 
1363 static int
1364 tmpfs_whiteout(struct vop_whiteout_args *ap)
1365 {
1366 	struct vnode *dvp = ap->a_dvp;
1367 	struct componentname *cnp = ap->a_cnp;
1368 	struct tmpfs_dirent *de;
1369 
1370 	switch (ap->a_flags) {
1371 	case LOOKUP:
1372 		return (0);
1373 	case CREATE:
1374 		de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(dvp), NULL, cnp);
1375 		if (de != NULL)
1376 			return (de->td_node == NULL ? 0 : EEXIST);
1377 		return (tmpfs_dir_whiteout_add(dvp, cnp));
1378 	case DELETE:
1379 		tmpfs_dir_whiteout_remove(dvp, cnp);
1380 		return (0);
1381 	default:
1382 		panic("tmpfs_whiteout: unknown op");
1383 	}
1384 }
1385 
1386 /*
1387  * vnode operations vector used for files stored in a tmpfs file system.
1388  */
1389 struct vop_vector tmpfs_vnodeop_entries = {
1390 	.vop_default =			&default_vnodeops,
1391 	.vop_lookup =			vfs_cache_lookup,
1392 	.vop_cachedlookup =		tmpfs_lookup,
1393 	.vop_create =			tmpfs_create,
1394 	.vop_mknod =			tmpfs_mknod,
1395 	.vop_open =			tmpfs_open,
1396 	.vop_close =			tmpfs_close,
1397 	.vop_access =			tmpfs_access,
1398 	.vop_getattr =			tmpfs_getattr,
1399 	.vop_setattr =			tmpfs_setattr,
1400 	.vop_read =			tmpfs_read,
1401 	.vop_write =			tmpfs_write,
1402 	.vop_fsync =			tmpfs_fsync,
1403 	.vop_remove =			tmpfs_remove,
1404 	.vop_link =			tmpfs_link,
1405 	.vop_rename =			tmpfs_rename,
1406 	.vop_mkdir =			tmpfs_mkdir,
1407 	.vop_rmdir =			tmpfs_rmdir,
1408 	.vop_symlink =			tmpfs_symlink,
1409 	.vop_readdir =			tmpfs_readdir,
1410 	.vop_readlink =			tmpfs_readlink,
1411 	.vop_inactive =			tmpfs_inactive,
1412 	.vop_reclaim =			tmpfs_reclaim,
1413 	.vop_print =			tmpfs_print,
1414 	.vop_pathconf =			tmpfs_pathconf,
1415 	.vop_vptofh =			tmpfs_vptofh,
1416 	.vop_whiteout =			tmpfs_whiteout,
1417 	.vop_bmap =			VOP_EOPNOTSUPP,
1418 };
1419 
1420