1/*-
2 * Copyright (c) 1994 Jan-Simon Pendry
3 * Copyright (c) 1994
4 * The Regents of the University of California. All rights reserved.
5 * Copyright (c) 2005, 2006 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc.
6 * Copyright (c) 2006 Daichi Goto <daichi@freebsd.org>
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry.
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 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * @(#)union_subr.c 8.20 (Berkeley) 5/20/95
36 * $FreeBSD: head/sys/fs/unionfs/union_subr.c 193511 2009-06-05 14:55:22Z rwatson $
37 */
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/kernel.h>
42#include <sys/lock.h>
43#include <sys/mutex.h>
44#include <sys/malloc.h>
45#include <sys/mount.h>
46#include <sys/namei.h>
47#include <sys/proc.h>
48#include <sys/vnode.h>
49#include <sys/dirent.h>
50#include <sys/fcntl.h>
51#include <sys/filedesc.h>
52#include <sys/stat.h>
53#include <sys/resourcevar.h>
54
55#include <security/mac/mac_framework.h>
56
57#include <vm/uma.h>
58
59#include <fs/unionfs/union.h>
60
61#define NUNIONFSNODECACHE 16
62
63static MALLOC_DEFINE(M_UNIONFSHASH, "UNIONFS hash", "UNIONFS hash table");
64MALLOC_DEFINE(M_UNIONFSNODE, "UNIONFS node", "UNIONFS vnode private part");
65MALLOC_DEFINE(M_UNIONFSPATH, "UNIONFS path", "UNIONFS path private part");
66
67/*
68 * Initialize
69 */
70int
71unionfs_init(struct vfsconf *vfsp)
72{
73 UNIONFSDEBUG("unionfs_init\n"); /* printed during system boot */
74 return (0);
75}
76
77/*
78 * Uninitialize
79 */
80int
81unionfs_uninit(struct vfsconf *vfsp)
82{
83 return (0);
84}
85
86static struct unionfs_node_hashhead *
87unionfs_get_hashhead(struct vnode *dvp, char *path)
88{
89 int count;
90 char hash;
91 struct unionfs_node *unp;
92
93 hash = 0;
94 unp = VTOUNIONFS(dvp);
95 if (path != NULL) {
96 for (count = 0; path[count]; count++)
97 hash += path[count];
98 }
99
100 return (&(unp->un_hashtbl[hash & (unp->un_hashmask)]));
101}
102
103/*
104 * Get the cached vnode.
105 */
106static struct vnode *
107unionfs_get_cached_vnode(struct vnode *uvp, struct vnode *lvp,
108 struct vnode *dvp, char *path)
109{
110 struct unionfs_node_hashhead *hd;
111 struct unionfs_node *unp;
112 struct vnode *vp;
113
114 KASSERT((uvp == NULLVP || uvp->v_type == VDIR),
115 ("unionfs_get_cached_vnode: v_type != VDIR"));
116 KASSERT((lvp == NULLVP || lvp->v_type == VDIR),
117 ("unionfs_get_cached_vnode: v_type != VDIR"));
118
119 VI_LOCK(dvp);
120 hd = unionfs_get_hashhead(dvp, path);
121 LIST_FOREACH(unp, hd, un_hash) {
122 if (!strcmp(unp->un_path, path)) {
123 vp = UNIONFSTOV(unp);
124 VI_LOCK_FLAGS(vp, MTX_DUPOK);
125 VI_UNLOCK(dvp);
126 vp->v_iflag &= ~VI_OWEINACT;
127 if ((vp->v_iflag & (VI_DOOMED | VI_DOINGINACT)) != 0) {
128 VI_UNLOCK(vp);
129 vp = NULLVP;
130 } else
131 VI_UNLOCK(vp);
132 return (vp);
133 }
134 }
135 VI_UNLOCK(dvp);
136
137 return (NULLVP);
138}
139
140/*
141 * Add the new vnode into cache.
142 */
143static struct vnode *
144unionfs_ins_cached_vnode(struct unionfs_node *uncp,
145 struct vnode *dvp, char *path)
146{
147 struct unionfs_node_hashhead *hd;
148 struct unionfs_node *unp;
149 struct vnode *vp;
150
151 KASSERT((uncp->un_uppervp==NULLVP || uncp->un_uppervp->v_type==VDIR),
152 ("unionfs_ins_cached_vnode: v_type != VDIR"));
153 KASSERT((uncp->un_lowervp==NULLVP || uncp->un_lowervp->v_type==VDIR),
154 ("unionfs_ins_cached_vnode: v_type != VDIR"));
155
156 VI_LOCK(dvp);
157 hd = unionfs_get_hashhead(dvp, path);
158 LIST_FOREACH(unp, hd, un_hash) {
159 if (!strcmp(unp->un_path, path)) {
160 vp = UNIONFSTOV(unp);
161 VI_LOCK_FLAGS(vp, MTX_DUPOK);
162 vp->v_iflag &= ~VI_OWEINACT;
163 if ((vp->v_iflag & (VI_DOOMED | VI_DOINGINACT)) != 0) {
164 LIST_INSERT_HEAD(hd, uncp, un_hash);
165 VI_UNLOCK(vp);
166 vp = NULLVP;
167 } else
168 VI_UNLOCK(vp);
169 VI_UNLOCK(dvp);
170 return (vp);
171 }
172 }
173
174 LIST_INSERT_HEAD(hd, uncp, un_hash);
175 VI_UNLOCK(dvp);
176
177 return (NULLVP);
178}
179
180/*
181 * Remove the vnode.
182 */
183static void
184unionfs_rem_cached_vnode(struct unionfs_node *unp, struct vnode *dvp)
185{
186 KASSERT((unp != NULL), ("unionfs_rem_cached_vnode: null node"));
187 KASSERT((dvp != NULLVP),
188 ("unionfs_rem_cached_vnode: null parent vnode"));
189 KASSERT((unp->un_hash.le_prev != NULL),
190 ("unionfs_rem_cached_vnode: null hash"));
191
192 VI_LOCK(dvp);
193 LIST_REMOVE(unp, un_hash);
194 unp->un_hash.le_next = NULL;
195 unp->un_hash.le_prev = NULL;
196 VI_UNLOCK(dvp);
197}
198
199/*
200 * Make a new or get existing unionfs node.
201 *
202 * uppervp and lowervp should be unlocked. Because if new unionfs vnode is
203 * locked, uppervp or lowervp is locked too. In order to prevent dead lock,
204 * you should not lock plurality simultaneously.
205 */
206int
207unionfs_nodeget(struct mount *mp, struct vnode *uppervp,
208 struct vnode *lowervp, struct vnode *dvp,
209 struct vnode **vpp, struct componentname *cnp,
210 struct thread *td)
211{
212 struct unionfs_mount *ump;
213 struct unionfs_node *unp;
214 struct vnode *vp;
215 int error;
216 int lkflags;
217 enum vtype vt;
218 char *path;
219
220 ump = MOUNTTOUNIONFSMOUNT(mp);
221 lkflags = (cnp ? cnp->cn_lkflags : 0);
222 path = (cnp ? cnp->cn_nameptr : NULL);
223 *vpp = NULLVP;
224
225 if (uppervp == NULLVP && lowervp == NULLVP)
226 panic("unionfs_nodeget: upper and lower is null");
227
228 vt = (uppervp != NULLVP ? uppervp->v_type : lowervp->v_type);
229
230 /* If it has no ISLASTCN flag, path check is skipped. */
231 if (cnp && !(cnp->cn_flags & ISLASTCN))
232 path = NULL;
233
234 /* check the cache */
235 if (path != NULL && dvp != NULLVP && vt == VDIR) {
236 vp = unionfs_get_cached_vnode(uppervp, lowervp, dvp, path);
237 if (vp != NULLVP) {
238 vref(vp);
239 *vpp = vp;
240 goto unionfs_nodeget_out;
241 }
242 }
243
244 if ((uppervp == NULLVP || ump->um_uppervp != uppervp) ||
245 (lowervp == NULLVP || ump->um_lowervp != lowervp)) {
246 /* dvp will be NULLVP only in case of root vnode. */
247 if (dvp == NULLVP)
248 return (EINVAL);
249 }
250
251 /*
252 * Do the MALLOC before the getnewvnode since doing so afterward
253 * might cause a bogus v_data pointer to get dereferenced elsewhere
254 * if MALLOC should block.
255 */
256 unp = malloc(sizeof(struct unionfs_node),
257 M_UNIONFSNODE, M_WAITOK | M_ZERO);
258
259 error = getnewvnode("unionfs", mp, &unionfs_vnodeops, &vp);
260 if (error != 0) {
261 free(unp, M_UNIONFSNODE);
262 return (error);
263 }
264 error = insmntque(vp, mp); /* XXX: Too early for mpsafe fs */
265 if (error != 0) {
266 free(unp, M_UNIONFSNODE);
267 return (error);
268 }
269 if (dvp != NULLVP)
270 vref(dvp);
271 if (uppervp != NULLVP)
272 vref(uppervp);
273 if (lowervp != NULLVP)
274 vref(lowervp);
275
276 if (vt == VDIR)
277 unp->un_hashtbl = hashinit(NUNIONFSNODECACHE, M_UNIONFSHASH,
278 &(unp->un_hashmask));
279
280 unp->un_vnode = vp;
281 unp->un_uppervp = uppervp;
282 unp->un_lowervp = lowervp;
283 unp->un_dvp = dvp;
284 if (uppervp != NULLVP)
285 vp->v_vnlock = uppervp->v_vnlock;
286 else
287 vp->v_vnlock = lowervp->v_vnlock;
288
289 if (path != NULL) {
290 unp->un_path = (char *)
291 malloc(cnp->cn_namelen +1, M_UNIONFSPATH, M_WAITOK|M_ZERO);
292 bcopy(cnp->cn_nameptr, unp->un_path, cnp->cn_namelen);
293 unp->un_path[cnp->cn_namelen] = '\0';
294 }
295 vp->v_type = vt;
296 vp->v_data = unp;
297
298 if ((uppervp != NULLVP && ump->um_uppervp == uppervp) &&
299 (lowervp != NULLVP && ump->um_lowervp == lowervp))
300 vp->v_vflag |= VV_ROOT;
301
302 if (path != NULL && dvp != NULLVP && vt == VDIR)
303 *vpp = unionfs_ins_cached_vnode(unp, dvp, path);
304 if ((*vpp) != NULLVP) {
305 if (dvp != NULLVP)
306 vrele(dvp);
307 if (uppervp != NULLVP)
308 vrele(uppervp);
309 if (lowervp != NULLVP)
310 vrele(lowervp);
311
312 unp->un_uppervp = NULLVP;
313 unp->un_lowervp = NULLVP;
314 unp->un_dvp = NULLVP;
315 vrele(vp);
316 vp = *vpp;
317 vref(vp);
318 } else
319 *vpp = vp;
320
321unionfs_nodeget_out:
322 if (lkflags & LK_TYPE_MASK)
323 vn_lock(vp, lkflags | LK_RETRY);
324
325 return (0);
326}
327
328/*
329 * Clean up the unionfs node.
330 */
331void
332unionfs_noderem(struct vnode *vp, struct thread *td)
333{
334 int vfslocked;
335 int count;
336 struct unionfs_node *unp, *unp_t1, *unp_t2;
337 struct unionfs_node_hashhead *hd;
338 struct unionfs_node_status *unsp, *unsp_tmp;
339 struct vnode *lvp;
340 struct vnode *uvp;
341 struct vnode *dvp;
342
343 /*
344 * Use the interlock to protect the clearing of v_data to
345 * prevent faults in unionfs_lock().
346 */
347 VI_LOCK(vp);
348 unp = VTOUNIONFS(vp);
349 lvp = unp->un_lowervp;
350 uvp = unp->un_uppervp;
351 dvp = unp->un_dvp;
352 unp->un_lowervp = unp->un_uppervp = NULLVP;
353
354 vp->v_vnlock = &(vp->v_lock);
355 vp->v_data = NULL;
356 lockmgr(vp->v_vnlock, LK_EXCLUSIVE | LK_INTERLOCK, VI_MTX(vp));
357 if (lvp != NULLVP)
358 VOP_UNLOCK(lvp, 0);
359 if (uvp != NULLVP)
360 VOP_UNLOCK(uvp, 0);
361 vp->v_object = NULL;
362
363 if (dvp != NULLVP && unp->un_hash.le_prev != NULL)
364 unionfs_rem_cached_vnode(unp, dvp);
365
366 if (lvp != NULLVP) {
367 vfslocked = VFS_LOCK_GIANT(lvp->v_mount);
368 vrele(lvp);
369 VFS_UNLOCK_GIANT(vfslocked);
370 }
371 if (uvp != NULLVP) {
372 vfslocked = VFS_LOCK_GIANT(uvp->v_mount);
373 vrele(uvp);
374 VFS_UNLOCK_GIANT(vfslocked);
375 }
376 if (dvp != NULLVP) {
377 vfslocked = VFS_LOCK_GIANT(dvp->v_mount);
378 vrele(dvp);
379 VFS_UNLOCK_GIANT(vfslocked);
380 unp->un_dvp = NULLVP;
381 }
382 if (unp->un_path != NULL) {
383 free(unp->un_path, M_UNIONFSPATH);
384 unp->un_path = NULL;
385 }
386
387 if (unp->un_hashtbl != NULL) {
388 for (count = 0; count <= unp->un_hashmask; count++) {
389 hd = unp->un_hashtbl + count;
390 LIST_FOREACH_SAFE(unp_t1, hd, un_hash, unp_t2) {
391 LIST_REMOVE(unp_t1, un_hash);
392 unp_t1->un_hash.le_next = NULL;
393 unp_t1->un_hash.le_prev = NULL;
394 }
395 }
396 hashdestroy(unp->un_hashtbl, M_UNIONFSHASH, unp->un_hashmask);
397 }
398
399 LIST_FOREACH_SAFE(unsp, &(unp->un_unshead), uns_list, unsp_tmp) {
400 LIST_REMOVE(unsp, uns_list);
401 free(unsp, M_TEMP);
402 }
403 free(unp, M_UNIONFSNODE);
404}
405
406/*
407 * Get the unionfs node status.
408 * You need exclusive lock this vnode.
409 */
410void
411unionfs_get_node_status(struct unionfs_node *unp, struct thread *td,
412 struct unionfs_node_status **unspp)
413{
414 struct unionfs_node_status *unsp;
415 pid_t pid = td->td_proc->p_pid;
416
417 KASSERT(NULL != unspp, ("null pointer"));
418 ASSERT_VOP_ELOCKED(UNIONFSTOV(unp), "unionfs_get_node_status");
419
420 LIST_FOREACH(unsp, &(unp->un_unshead), uns_list) {
421 if (unsp->uns_pid == pid) {
422 *unspp = unsp;
423 return;
424 }
425 }
426
427 /* create a new unionfs node status */
428 unsp = malloc(sizeof(struct unionfs_node_status),
429 M_TEMP, M_WAITOK | M_ZERO);
430
431 unsp->uns_pid = pid;
432 LIST_INSERT_HEAD(&(unp->un_unshead), unsp, uns_list);
433
434 *unspp = unsp;
435}
436
437/*
438 * Remove the unionfs node status, if you can.
439 * You need exclusive lock this vnode.
440 */
441void
442unionfs_tryrem_node_status(struct unionfs_node *unp,
443 struct unionfs_node_status *unsp)
444{
445 KASSERT(NULL != unsp, ("null pointer"));
446 ASSERT_VOP_ELOCKED(UNIONFSTOV(unp), "unionfs_get_node_status");
447
448 if (0 < unsp->uns_lower_opencnt || 0 < unsp->uns_upper_opencnt)
449 return;
450
451 LIST_REMOVE(unsp, uns_list);
452 free(unsp, M_TEMP);
453}
454
455/*
456 * Create upper node attr.
457 */
458void
459unionfs_create_uppervattr_core(struct unionfs_mount *ump,
460 struct vattr *lva,
461 struct vattr *uva,
462 struct thread *td)
463{
464 VATTR_NULL(uva);
465 uva->va_type = lva->va_type;
466 uva->va_atime = lva->va_atime;
467 uva->va_mtime = lva->va_mtime;
468 uva->va_ctime = lva->va_ctime;
469
470 switch (ump->um_copymode) {
471 case UNIONFS_TRANSPARENT:
472 uva->va_mode = lva->va_mode;
473 uva->va_uid = lva->va_uid;
474 uva->va_gid = lva->va_gid;
475 break;
476 case UNIONFS_MASQUERADE:
477 if (ump->um_uid == lva->va_uid) {
478 uva->va_mode = lva->va_mode & 077077;
479 uva->va_mode |= (lva->va_type == VDIR ? ump->um_udir : ump->um_ufile) & 0700;
480 uva->va_uid = lva->va_uid;
481 uva->va_gid = lva->va_gid;
482 } else {
483 uva->va_mode = (lva->va_type == VDIR ? ump->um_udir : ump->um_ufile);
484 uva->va_uid = ump->um_uid;
485 uva->va_gid = ump->um_gid;
486 }
487 break;
488 default: /* UNIONFS_TRADITIONAL */
489 FILEDESC_SLOCK(td->td_proc->p_fd);
490 uva->va_mode = 0777 & ~td->td_proc->p_fd->fd_cmask;
491 FILEDESC_SUNLOCK(td->td_proc->p_fd);
492 uva->va_uid = ump->um_uid;
493 uva->va_gid = ump->um_gid;
494 break;
495 }
496}
497
498/*
499 * Create upper node attr.
500 */
501int
502unionfs_create_uppervattr(struct unionfs_mount *ump,
503 struct vnode *lvp,
504 struct vattr *uva,
505 struct ucred *cred,
506 struct thread *td)
507{
508 int error;
509 struct vattr lva;
510
511 if ((error = VOP_GETATTR(lvp, &lva, cred)))
512 return (error);
513
514 unionfs_create_uppervattr_core(ump, &lva, uva, td);
515
516 return (error);
517}
518
519/*
520 * relookup
521 *
522 * dvp should be locked on entry and will be locked on return.
523 *
524 * If an error is returned, *vpp will be invalid, otherwise it will hold a
525 * locked, referenced vnode. If *vpp == dvp then remember that only one
526 * LK_EXCLUSIVE lock is held.
527 */
528int
529unionfs_relookup(struct vnode *dvp, struct vnode **vpp,
530 struct componentname *cnp, struct componentname *cn,
531 struct thread *td, char *path, int pathlen, u_long nameiop)
532{
533 int error;
534
535 cn->cn_namelen = pathlen;
536 cn->cn_pnbuf = uma_zalloc(namei_zone, M_WAITOK);
537 bcopy(path, cn->cn_pnbuf, pathlen);
538 cn->cn_pnbuf[pathlen] = '\0';
539
540 cn->cn_nameiop = nameiop;
541 cn->cn_flags = (LOCKPARENT | LOCKLEAF | HASBUF | SAVENAME | ISLASTCN);
542 cn->cn_lkflags = LK_EXCLUSIVE;
543 cn->cn_thread = td;
544 cn->cn_cred = cnp->cn_cred;
545
546 cn->cn_nameptr = cn->cn_pnbuf;
547 cn->cn_consume = cnp->cn_consume;
548
549 if (nameiop == DELETE)
550 cn->cn_flags |= (cnp->cn_flags & (DOWHITEOUT | SAVESTART));
551 else if (RENAME == nameiop)
552 cn->cn_flags |= (cnp->cn_flags & SAVESTART);
553
554 vref(dvp);
555 VOP_UNLOCK(dvp, 0);
556
557 if ((error = relookup(dvp, vpp, cn))) {
558 uma_zfree(namei_zone, cn->cn_pnbuf);
559 cn->cn_flags &= ~HASBUF;
560 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
561 } else
562 vrele(dvp);
563
564 return (error);
565}
566
567/*
568 * relookup for CREATE namei operation.
569 *
570 * dvp is unionfs vnode. dvp should be locked.
571 *
572 * If it called 'unionfs_copyfile' function by unionfs_link etc,
573 * VOP_LOOKUP information is broken.
574 * So it need relookup in order to create link etc.
575 */
576int
577unionfs_relookup_for_create(struct vnode *dvp, struct componentname *cnp,
578 struct thread *td)
579{
580 int error;
581 struct vnode *udvp;
582 struct vnode *vp;
583 struct componentname cn;
584
585 udvp = UNIONFSVPTOUPPERVP(dvp);
586 vp = NULLVP;
587
588 error = unionfs_relookup(udvp, &vp, cnp, &cn, td, cnp->cn_nameptr,
589 strlen(cnp->cn_nameptr), CREATE);
590 if (error)
591 return (error);
592
593 if (vp != NULLVP) {
594 if (udvp == vp)
595 vrele(vp);
596 else
597 vput(vp);
598
599 error = EEXIST;
600 }
601
602 if (cn.cn_flags & HASBUF) {
603 uma_zfree(namei_zone, cn.cn_pnbuf);
604 cn.cn_flags &= ~HASBUF;
605 }
606
607 if (!error) {
608 cn.cn_flags |= (cnp->cn_flags & HASBUF);
609 cnp->cn_flags = cn.cn_flags;
610 }
611
612 return (error);
613}
614
615/*
616 * relookup for DELETE namei operation.
617 *
618 * dvp is unionfs vnode. dvp should be locked.
619 */
620int
621unionfs_relookup_for_delete(struct vnode *dvp, struct componentname *cnp,
622 struct thread *td)
623{
624 int error;
625 struct vnode *udvp;
626 struct vnode *vp;
627 struct componentname cn;
628
629 udvp = UNIONFSVPTOUPPERVP(dvp);
630 vp = NULLVP;
631
632 error = unionfs_relookup(udvp, &vp, cnp, &cn, td, cnp->cn_nameptr,
633 strlen(cnp->cn_nameptr), DELETE);
634 if (error)
635 return (error);
636
637 if (vp == NULLVP)
638 error = ENOENT;
639 else {
640 if (udvp == vp)
641 vrele(vp);
642 else
643 vput(vp);
644 }
645
646 if (cn.cn_flags & HASBUF) {
647 uma_zfree(namei_zone, cn.cn_pnbuf);
648 cn.cn_flags &= ~HASBUF;
649 }
650
651 if (!error) {
652 cn.cn_flags |= (cnp->cn_flags & HASBUF);
653 cnp->cn_flags = cn.cn_flags;
654 }
655
656 return (error);
657}
658
659/*
660 * relookup for RENAME namei operation.
661 *
662 * dvp is unionfs vnode. dvp should be locked.
663 */
664int
665unionfs_relookup_for_rename(struct vnode *dvp, struct componentname *cnp,
666 struct thread *td)
667{
668 int error;
669 struct vnode *udvp;
670 struct vnode *vp;
671 struct componentname cn;
672
673 udvp = UNIONFSVPTOUPPERVP(dvp);
674 vp = NULLVP;
675
676 error = unionfs_relookup(udvp, &vp, cnp, &cn, td, cnp->cn_nameptr,
677 strlen(cnp->cn_nameptr), RENAME);
678 if (error)
679 return (error);
680
681 if (vp != NULLVP) {
682 if (udvp == vp)
683 vrele(vp);
684 else
685 vput(vp);
686 }
687
688 if (cn.cn_flags & HASBUF) {
689 uma_zfree(namei_zone, cn.cn_pnbuf);
690 cn.cn_flags &= ~HASBUF;
691 }
692
693 if (!error) {
694 cn.cn_flags |= (cnp->cn_flags & HASBUF);
695 cnp->cn_flags = cn.cn_flags;
696 }
697
698 return (error);
699
700}
701
702/*
703 * Update the unionfs_node.
704 *
705 * uvp is new locked upper vnode. unionfs vnode's lock will be exchanged to the
706 * uvp's lock and lower's lock will be unlocked.
707 */
708static void
709unionfs_node_update(struct unionfs_node *unp, struct vnode *uvp,
710 struct thread *td)
711{
712 unsigned count, lockrec;
713 struct vnode *vp;
714 struct vnode *lvp;
715 struct vnode *dvp;
716
717 vp = UNIONFSTOV(unp);
718 lvp = unp->un_lowervp;
719 ASSERT_VOP_ELOCKED(lvp, "unionfs_node_update");
720 dvp = unp->un_dvp;
721
722 /*
723 * lock update
724 */
725 VI_LOCK(vp);
726 unp->un_uppervp = uvp;
727 vp->v_vnlock = uvp->v_vnlock;
728 VI_UNLOCK(vp);
729 lockrec = lvp->v_vnlock->lk_recurse;
730 for (count = 0; count < lockrec; count++)
731 vn_lock(uvp, LK_EXCLUSIVE | LK_CANRECURSE | LK_RETRY);
732
733 /*
734 * cache update
735 */
736 if (unp->un_path != NULL && dvp != NULLVP && vp->v_type == VDIR) {
737 static struct unionfs_node_hashhead *hd;
738
739 VI_LOCK(dvp);
740 hd = unionfs_get_hashhead(dvp, unp->un_path);
741 LIST_REMOVE(unp, un_hash);
742 LIST_INSERT_HEAD(hd, unp, un_hash);
743 VI_UNLOCK(dvp);
744 }
745}
746
747/*
748 * Create a new shadow dir.
749 *
750 * udvp should be locked on entry and will be locked on return.
751 *
752 * If no error returned, unp will be updated.
753 */
754int
755unionfs_mkshadowdir(struct unionfs_mount *ump, struct vnode *udvp,
756 struct unionfs_node *unp, struct componentname *cnp,
757 struct thread *td)
758{
759 int error;
760 struct vnode *lvp;
761 struct vnode *uvp;
762 struct vattr va;
763 struct vattr lva;
764 struct componentname cn;
765 struct mount *mp;
766 struct ucred *cred;
767 struct ucred *credbk;
768 struct uidinfo *rootinfo;
769
770 if (unp->un_uppervp != NULLVP)
771 return (EEXIST);
772
773 lvp = unp->un_lowervp;
774 uvp = NULLVP;
775 credbk = cnp->cn_cred;
776
777 /* Authority change to root */
778 rootinfo = uifind((uid_t)0);
779 cred = crdup(cnp->cn_cred);
780 chgproccnt(cred->cr_ruidinfo, 1, 0);
781 change_euid(cred, rootinfo);
782 change_ruid(cred, rootinfo);
783 change_svuid(cred, (uid_t)0);
784 uifree(rootinfo);
785 cnp->cn_cred = cred;
786
787 memset(&cn, 0, sizeof(cn));
788
789 if ((error = VOP_GETATTR(lvp, &lva, cnp->cn_cred)))
790 goto unionfs_mkshadowdir_abort;
791
792 if ((error = unionfs_relookup(udvp, &uvp, cnp, &cn, td, cnp->cn_nameptr, cnp->cn_namelen, CREATE)))
793 goto unionfs_mkshadowdir_abort;
794 if (uvp != NULLVP) {
795 if (udvp == uvp)
796 vrele(uvp);
797 else
798 vput(uvp);
799
800 error = EEXIST;
801 goto unionfs_mkshadowdir_free_out;
802 }
803
804 if ((error = vn_start_write(udvp, &mp, V_WAIT | PCATCH)))
805 goto unionfs_mkshadowdir_free_out;
806 unionfs_create_uppervattr_core(ump, &lva, &va, td);
807
808 error = VOP_MKDIR(udvp, &uvp, &cn, &va);
809
810 if (!error) {
811 unionfs_node_update(unp, uvp, td);
812
813 /*
814 * XXX The bug which cannot set uid/gid was corrected.
815 * Ignore errors.
816 */
817 va.va_type = VNON;
818 VOP_SETATTR(uvp, &va, cn.cn_cred);
819 }
820 vn_finished_write(mp);
821
822unionfs_mkshadowdir_free_out:
823 if (cn.cn_flags & HASBUF) {
824 uma_zfree(namei_zone, cn.cn_pnbuf);
825 cn.cn_flags &= ~HASBUF;
826 }
827
828unionfs_mkshadowdir_abort:
829 cnp->cn_cred = credbk;
830 chgproccnt(cred->cr_ruidinfo, -1, 0);
831 crfree(cred);
832
833 return (error);
834}
835
836/*
837 * Create a new whiteout.
838 *
839 * dvp should be locked on entry and will be locked on return.
840 */
841int
842unionfs_mkwhiteout(struct vnode *dvp, struct componentname *cnp,
843 struct thread *td, char *path)
844{
845 int error;
846 struct vnode *wvp;
847 struct componentname cn;
848 struct mount *mp;
849
850 if (path == NULL)
851 path = cnp->cn_nameptr;
852
853 wvp = NULLVP;
854 if ((error = unionfs_relookup(dvp, &wvp, cnp, &cn, td, path, strlen(path), CREATE)))
855 return (error);
856 if (wvp != NULLVP) {
857 if (cn.cn_flags & HASBUF) {
858 uma_zfree(namei_zone, cn.cn_pnbuf);
859 cn.cn_flags &= ~HASBUF;
860 }
861 if (dvp == wvp)
862 vrele(wvp);
863 else
864 vput(wvp);
865
866 return (EEXIST);
867 }
868
869 if ((error = vn_start_write(dvp, &mp, V_WAIT | PCATCH)))
870 goto unionfs_mkwhiteout_free_out;
871 error = VOP_WHITEOUT(dvp, &cn, CREATE);
872
873 vn_finished_write(mp);
874
875unionfs_mkwhiteout_free_out:
876 if (cn.cn_flags & HASBUF) {
877 uma_zfree(namei_zone, cn.cn_pnbuf);
878 cn.cn_flags &= ~HASBUF;
879 }
880
881 return (error);
882}
883
884/*
885 * Create a new vnode for create a new shadow file.
886 *
887 * If an error is returned, *vpp will be invalid, otherwise it will hold a
888 * locked, referenced and opened vnode.
889 *
890 * unp is never updated.
891 */
892static int
893unionfs_vn_create_on_upper(struct vnode **vpp, struct vnode *udvp,
894 struct unionfs_node *unp, struct vattr *uvap,
895 struct thread *td)
896{
897 struct unionfs_mount *ump;
898 struct vnode *vp;
899 struct vnode *lvp;
900 struct ucred *cred;
901 struct vattr lva;
902 int fmode;
903 int error;
904 struct componentname cn;
905
906 ump = MOUNTTOUNIONFSMOUNT(UNIONFSTOV(unp)->v_mount);
907 vp = NULLVP;
908 lvp = unp->un_lowervp;
909 cred = td->td_ucred;
910 fmode = FFLAGS(O_WRONLY | O_CREAT | O_TRUNC | O_EXCL);
911 error = 0;
912
913 if ((error = VOP_GETATTR(lvp, &lva, cred)) != 0)
914 return (error);
915 unionfs_create_uppervattr_core(ump, &lva, uvap, td);
916
917 if (unp->un_path == NULL)
918 panic("unionfs: un_path is null");
919
920 cn.cn_namelen = strlen(unp->un_path);
921 cn.cn_pnbuf = uma_zalloc(namei_zone, M_WAITOK);
922 bcopy(unp->un_path, cn.cn_pnbuf, cn.cn_namelen + 1);
923 cn.cn_nameiop = CREATE;
924 cn.cn_flags = (LOCKPARENT | LOCKLEAF | HASBUF | SAVENAME | ISLASTCN);
925 cn.cn_lkflags = LK_EXCLUSIVE;
926 cn.cn_thread = td;
927 cn.cn_cred = cred;
928 cn.cn_nameptr = cn.cn_pnbuf;
929 cn.cn_consume = 0;
930
931 vref(udvp);
932 if ((error = relookup(udvp, &vp, &cn)) != 0)
933 goto unionfs_vn_create_on_upper_free_out2;
934 vrele(udvp);
935
936 if (vp != NULLVP) {
937 if (vp == udvp)
938 vrele(vp);
939 else
940 vput(vp);
941 error = EEXIST;
942 goto unionfs_vn_create_on_upper_free_out1;
943 }
944
945 if ((error = VOP_CREATE(udvp, &vp, &cn, uvap)) != 0)
946 goto unionfs_vn_create_on_upper_free_out1;
947
948 if ((error = VOP_OPEN(vp, fmode, cred, td, NULL)) != 0) {
949 vput(vp);
950 goto unionfs_vn_create_on_upper_free_out1;
951 }
952 vp->v_writecount++;
953 *vpp = vp;
954
955unionfs_vn_create_on_upper_free_out1:
956 VOP_UNLOCK(udvp, 0);
957
958unionfs_vn_create_on_upper_free_out2:
959 if (cn.cn_flags & HASBUF) {
960 uma_zfree(namei_zone, cn.cn_pnbuf);
961 cn.cn_flags &= ~HASBUF;
962 }
963
964 return (error);
965}
966
967/*
968 * Copy from lvp to uvp.
969 *
970 * lvp and uvp should be locked and opened on entry and will be locked and
971 * opened on return.
972 */
973static int
974unionfs_copyfile_core(struct vnode *lvp, struct vnode *uvp,
975 struct ucred *cred, struct thread *td)
976{
977 int error;
978 off_t offset;
979 int count;
980 int bufoffset;
981 char *buf;
982 struct uio uio;
983 struct iovec iov;
984
985 error = 0;
986 memset(&uio, 0, sizeof(uio));
987
988 uio.uio_td = td;
989 uio.uio_segflg = UIO_SYSSPACE;
990 uio.uio_offset = 0;
991
992 buf = malloc(MAXBSIZE, M_TEMP, M_WAITOK);
993
994 while (error == 0) {
995 offset = uio.uio_offset;
996
997 uio.uio_iov = &iov;
998 uio.uio_iovcnt = 1;
999 iov.iov_base = buf;
1000 iov.iov_len = MAXBSIZE;
1001 uio.uio_resid = iov.iov_len;
1002 uio.uio_rw = UIO_READ;
1003
1004 if ((error = VOP_READ(lvp, &uio, 0, cred)) != 0)
1005 break;
1006 if ((count = MAXBSIZE - uio.uio_resid) == 0)
1007 break;
1008
1009 bufoffset = 0;
1010 while (bufoffset < count) {
1011 uio.uio_iov = &iov;
1012 uio.uio_iovcnt = 1;
1013 iov.iov_base = buf + bufoffset;
1014 iov.iov_len = count - bufoffset;
1015 uio.uio_offset = offset + bufoffset;
1016 uio.uio_resid = iov.iov_len;
1017 uio.uio_rw = UIO_WRITE;
1018
1019 if ((error = VOP_WRITE(uvp, &uio, 0, cred)) != 0)
1020 break;
1021
1022 bufoffset += (count - bufoffset) - uio.uio_resid;
1023 }
1024
1025 uio.uio_offset = offset + bufoffset;
1026 }
1027
1028 free(buf, M_TEMP);
1029
1030 return (error);
1031}
1032
1033/*
1034 * Copy file from lower to upper.
1035 *
1036 * If you need copy of the contents, set 1 to docopy. Otherwise, set 0 to
1037 * docopy.
1038 *
1039 * If no error returned, unp will be updated.
1040 */
1041int
1042unionfs_copyfile(struct unionfs_node *unp, int docopy, struct ucred *cred,
1043 struct thread *td)
1044{
1045 int error;
1046 struct mount *mp;
1047 struct vnode *udvp;
1048 struct vnode *lvp;
1049 struct vnode *uvp;
1050 struct vattr uva;
1051
1052 lvp = unp->un_lowervp;
1053 uvp = NULLVP;
1054
1055 if ((UNIONFSTOV(unp)->v_mount->mnt_flag & MNT_RDONLY))
1056 return (EROFS);
1057 if (unp->un_dvp == NULLVP)
1058 return (EINVAL);
1059 if (unp->un_uppervp != NULLVP)
1060 return (EEXIST);
1061 udvp = VTOUNIONFS(unp->un_dvp)->un_uppervp;
1062 if (udvp == NULLVP)
1063 return (EROFS);
1064 if ((udvp->v_mount->mnt_flag & MNT_RDONLY))
1065 return (EROFS);
1066
1067 error = VOP_ACCESS(lvp, VREAD, cred, td);
1068 if (error != 0)
1069 return (error);
1070
1071 if ((error = vn_start_write(udvp, &mp, V_WAIT | PCATCH)) != 0)
1072 return (error);
1073 error = unionfs_vn_create_on_upper(&uvp, udvp, unp, &uva, td);
1074 if (error != 0) {
1075 vn_finished_write(mp);
1076 return (error);
1077 }
1078
1079 if (docopy != 0) {
1080 error = VOP_OPEN(lvp, FREAD, cred, td, NULL);
1081 if (error == 0) {
1082 error = unionfs_copyfile_core(lvp, uvp, cred, td);
1083 VOP_CLOSE(lvp, FREAD, cred, td);
1084 }
1085 }
1086 VOP_CLOSE(uvp, FWRITE, cred, td);
1087 uvp->v_writecount--;
1088
1089 vn_finished_write(mp);
1090
1091 if (error == 0) {
1092 /* Reset the attributes. Ignore errors. */
1093 uva.va_type = VNON;
1094 VOP_SETATTR(uvp, &uva, cred);
1095 }
1096
1097 unionfs_node_update(unp, uvp, td);
1098
1099 return (error);
1100}
1101
1102/*
1103 * It checks whether vp can rmdir. (check empty)
1104 *
1105 * vp is unionfs vnode.
1106 * vp should be locked.
1107 */
1108int
1109unionfs_check_rmdir(struct vnode *vp, struct ucred *cred, struct thread *td)
1110{
1111 int error;
1112 int eofflag;
1113 int lookuperr;
1114 struct vnode *uvp;
1115 struct vnode *lvp;
1116 struct vnode *tvp;
1117 struct vattr va;
1118 struct componentname cn;
1119 /*
1120 * The size of buf needs to be larger than DIRBLKSIZ.
1121 */
1122 char buf[256 * 6];
1123 struct dirent *dp;
1124 struct dirent *edp;
1125 struct uio uio;
1126 struct iovec iov;
1127
1128 ASSERT_VOP_ELOCKED(vp, "unionfs_check_rmdir");
1129
1130 eofflag = 0;
1131 uvp = UNIONFSVPTOUPPERVP(vp);
1132 lvp = UNIONFSVPTOLOWERVP(vp);
1133
1134 /* check opaque */
1135 if ((error = VOP_GETATTR(uvp, &va, cred)) != 0)
1136 return (error);
1137 if (va.va_flags & OPAQUE)
1138 return (0);
1139
1140 /* open vnode */
1141#ifdef MAC
1142 if ((error = mac_vnode_check_open(cred, vp, VEXEC|VREAD)) != 0)
1143 return (error);
1144#endif
1145 if ((error = VOP_ACCESS(vp, VEXEC|VREAD, cred, td)) != 0)
1146 return (error);
1147 if ((error = VOP_OPEN(vp, FREAD, cred, td, NULL)) != 0)
1148 return (error);
1149
1150 uio.uio_rw = UIO_READ;
1151 uio.uio_segflg = UIO_SYSSPACE;
1152 uio.uio_td = td;
1153 uio.uio_offset = 0;
1154
1155#ifdef MAC
1156 error = mac_vnode_check_readdir(td->td_ucred, lvp);
1157#endif
1158 while (!error && !eofflag) {
1159 iov.iov_base = buf;
1160 iov.iov_len = sizeof(buf);
1161 uio.uio_iov = &iov;
1162 uio.uio_iovcnt = 1;
1163 uio.uio_resid = iov.iov_len;
1164
1165 error = VOP_READDIR(lvp, &uio, cred, &eofflag, NULL, NULL);
1166 if (error != 0)
1167 break;
1168 if (eofflag == 0 && uio.uio_resid == sizeof(buf)) {
1169#ifdef DIAGNOSTIC
1170 panic("bad readdir response from lower FS.");
1171#endif
1172 break;
1173 }
1174
1175 edp = (struct dirent*)&buf[sizeof(buf) - uio.uio_resid];
1176 for (dp = (struct dirent*)buf; !error && dp < edp;
1177 dp = (struct dirent*)((caddr_t)dp + dp->d_reclen)) {
1178 if (dp->d_type == DT_WHT ||
1179 (dp->d_namlen == 1 && dp->d_name[0] == '.') ||
1180 (dp->d_namlen == 2 && !bcmp(dp->d_name, "..", 2)))
1181 continue;
1182
1183 cn.cn_namelen = dp->d_namlen;
1184 cn.cn_pnbuf = NULL;
1185 cn.cn_nameptr = dp->d_name;
1186 cn.cn_nameiop = LOOKUP;
1187 cn.cn_flags = (LOCKPARENT | LOCKLEAF | SAVENAME | RDONLY | ISLASTCN);
1188 cn.cn_lkflags = LK_EXCLUSIVE;
1189 cn.cn_thread = td;
1190 cn.cn_cred = cred;
1191 cn.cn_consume = 0;
1192
1193 /*
1194 * check entry in lower.
1195 * Sometimes, readdir function returns
1196 * wrong entry.
1197 */
1198 lookuperr = VOP_LOOKUP(lvp, &tvp, &cn);
1199
1200 if (!lookuperr)
1201 vput(tvp);
1202 else
1203 continue; /* skip entry */
1204
1205 /*
1206 * check entry
1207 * If it has no exist/whiteout entry in upper,
1208 * directory is not empty.
1209 */
1210 cn.cn_flags = (LOCKPARENT | LOCKLEAF | SAVENAME | RDONLY | ISLASTCN);
1211 lookuperr = VOP_LOOKUP(uvp, &tvp, &cn);
1212
1213 if (!lookuperr)
1214 vput(tvp);
1215
1216 /* ignore exist or whiteout entry */
1217 if (!lookuperr ||
1218 (lookuperr == ENOENT && (cn.cn_flags & ISWHITEOUT)))
1219 continue;
1220
1221 error = ENOTEMPTY;
1222 }
1223 }
1224
1225 /* close vnode */
1226 VOP_CLOSE(vp, FREAD, cred, td);
1227
1228 return (error);
1229}
1230
1231#ifdef DIAGNOSTIC
1232
1233struct vnode *
1234unionfs_checkuppervp(struct vnode *vp, char *fil, int lno)
1235{
1236 struct unionfs_node *unp;
1237
1238 unp = VTOUNIONFS(vp);
1239
1240#ifdef notyet
1241 if (vp->v_op != unionfs_vnodeop_p) {
1242 printf("unionfs_checkuppervp: on non-unionfs-node.\n");
1243#ifdef KDB
1244 kdb_enter(KDB_WHY_UNIONFS,
1245 "unionfs_checkuppervp: on non-unionfs-node.\n");
1246#endif
1247 panic("unionfs_checkuppervp");
1248 };
1249#endif
1250 return (unp->un_uppervp);
1251}
1252
1253struct vnode *
1254unionfs_checklowervp(struct vnode *vp, char *fil, int lno)
1255{
1256 struct unionfs_node *unp;
1257
1258 unp = VTOUNIONFS(vp);
1259
1260#ifdef notyet
1261 if (vp->v_op != unionfs_vnodeop_p) {
1262 printf("unionfs_checklowervp: on non-unionfs-node.\n");
1263#ifdef KDB
1264 kdb_enter(KDB_WHY_UNIONFS,
1265 "unionfs_checklowervp: on non-unionfs-node.\n");
1266#endif
1267 panic("unionfs_checklowervp");
1268 };
1269#endif
1270 return (unp->un_lowervp);
1271}
1272#endif
2 * Copyright (c) 1994 Jan-Simon Pendry
3 * Copyright (c) 1994
4 * The Regents of the University of California. All rights reserved.
5 * Copyright (c) 2005, 2006 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc.
6 * Copyright (c) 2006 Daichi Goto <daichi@freebsd.org>
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry.
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 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * @(#)union_subr.c 8.20 (Berkeley) 5/20/95
36 * $FreeBSD: head/sys/fs/unionfs/union_subr.c 193511 2009-06-05 14:55:22Z rwatson $
37 */
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/kernel.h>
42#include <sys/lock.h>
43#include <sys/mutex.h>
44#include <sys/malloc.h>
45#include <sys/mount.h>
46#include <sys/namei.h>
47#include <sys/proc.h>
48#include <sys/vnode.h>
49#include <sys/dirent.h>
50#include <sys/fcntl.h>
51#include <sys/filedesc.h>
52#include <sys/stat.h>
53#include <sys/resourcevar.h>
54
55#include <security/mac/mac_framework.h>
56
57#include <vm/uma.h>
58
59#include <fs/unionfs/union.h>
60
61#define NUNIONFSNODECACHE 16
62
63static MALLOC_DEFINE(M_UNIONFSHASH, "UNIONFS hash", "UNIONFS hash table");
64MALLOC_DEFINE(M_UNIONFSNODE, "UNIONFS node", "UNIONFS vnode private part");
65MALLOC_DEFINE(M_UNIONFSPATH, "UNIONFS path", "UNIONFS path private part");
66
67/*
68 * Initialize
69 */
70int
71unionfs_init(struct vfsconf *vfsp)
72{
73 UNIONFSDEBUG("unionfs_init\n"); /* printed during system boot */
74 return (0);
75}
76
77/*
78 * Uninitialize
79 */
80int
81unionfs_uninit(struct vfsconf *vfsp)
82{
83 return (0);
84}
85
86static struct unionfs_node_hashhead *
87unionfs_get_hashhead(struct vnode *dvp, char *path)
88{
89 int count;
90 char hash;
91 struct unionfs_node *unp;
92
93 hash = 0;
94 unp = VTOUNIONFS(dvp);
95 if (path != NULL) {
96 for (count = 0; path[count]; count++)
97 hash += path[count];
98 }
99
100 return (&(unp->un_hashtbl[hash & (unp->un_hashmask)]));
101}
102
103/*
104 * Get the cached vnode.
105 */
106static struct vnode *
107unionfs_get_cached_vnode(struct vnode *uvp, struct vnode *lvp,
108 struct vnode *dvp, char *path)
109{
110 struct unionfs_node_hashhead *hd;
111 struct unionfs_node *unp;
112 struct vnode *vp;
113
114 KASSERT((uvp == NULLVP || uvp->v_type == VDIR),
115 ("unionfs_get_cached_vnode: v_type != VDIR"));
116 KASSERT((lvp == NULLVP || lvp->v_type == VDIR),
117 ("unionfs_get_cached_vnode: v_type != VDIR"));
118
119 VI_LOCK(dvp);
120 hd = unionfs_get_hashhead(dvp, path);
121 LIST_FOREACH(unp, hd, un_hash) {
122 if (!strcmp(unp->un_path, path)) {
123 vp = UNIONFSTOV(unp);
124 VI_LOCK_FLAGS(vp, MTX_DUPOK);
125 VI_UNLOCK(dvp);
126 vp->v_iflag &= ~VI_OWEINACT;
127 if ((vp->v_iflag & (VI_DOOMED | VI_DOINGINACT)) != 0) {
128 VI_UNLOCK(vp);
129 vp = NULLVP;
130 } else
131 VI_UNLOCK(vp);
132 return (vp);
133 }
134 }
135 VI_UNLOCK(dvp);
136
137 return (NULLVP);
138}
139
140/*
141 * Add the new vnode into cache.
142 */
143static struct vnode *
144unionfs_ins_cached_vnode(struct unionfs_node *uncp,
145 struct vnode *dvp, char *path)
146{
147 struct unionfs_node_hashhead *hd;
148 struct unionfs_node *unp;
149 struct vnode *vp;
150
151 KASSERT((uncp->un_uppervp==NULLVP || uncp->un_uppervp->v_type==VDIR),
152 ("unionfs_ins_cached_vnode: v_type != VDIR"));
153 KASSERT((uncp->un_lowervp==NULLVP || uncp->un_lowervp->v_type==VDIR),
154 ("unionfs_ins_cached_vnode: v_type != VDIR"));
155
156 VI_LOCK(dvp);
157 hd = unionfs_get_hashhead(dvp, path);
158 LIST_FOREACH(unp, hd, un_hash) {
159 if (!strcmp(unp->un_path, path)) {
160 vp = UNIONFSTOV(unp);
161 VI_LOCK_FLAGS(vp, MTX_DUPOK);
162 vp->v_iflag &= ~VI_OWEINACT;
163 if ((vp->v_iflag & (VI_DOOMED | VI_DOINGINACT)) != 0) {
164 LIST_INSERT_HEAD(hd, uncp, un_hash);
165 VI_UNLOCK(vp);
166 vp = NULLVP;
167 } else
168 VI_UNLOCK(vp);
169 VI_UNLOCK(dvp);
170 return (vp);
171 }
172 }
173
174 LIST_INSERT_HEAD(hd, uncp, un_hash);
175 VI_UNLOCK(dvp);
176
177 return (NULLVP);
178}
179
180/*
181 * Remove the vnode.
182 */
183static void
184unionfs_rem_cached_vnode(struct unionfs_node *unp, struct vnode *dvp)
185{
186 KASSERT((unp != NULL), ("unionfs_rem_cached_vnode: null node"));
187 KASSERT((dvp != NULLVP),
188 ("unionfs_rem_cached_vnode: null parent vnode"));
189 KASSERT((unp->un_hash.le_prev != NULL),
190 ("unionfs_rem_cached_vnode: null hash"));
191
192 VI_LOCK(dvp);
193 LIST_REMOVE(unp, un_hash);
194 unp->un_hash.le_next = NULL;
195 unp->un_hash.le_prev = NULL;
196 VI_UNLOCK(dvp);
197}
198
199/*
200 * Make a new or get existing unionfs node.
201 *
202 * uppervp and lowervp should be unlocked. Because if new unionfs vnode is
203 * locked, uppervp or lowervp is locked too. In order to prevent dead lock,
204 * you should not lock plurality simultaneously.
205 */
206int
207unionfs_nodeget(struct mount *mp, struct vnode *uppervp,
208 struct vnode *lowervp, struct vnode *dvp,
209 struct vnode **vpp, struct componentname *cnp,
210 struct thread *td)
211{
212 struct unionfs_mount *ump;
213 struct unionfs_node *unp;
214 struct vnode *vp;
215 int error;
216 int lkflags;
217 enum vtype vt;
218 char *path;
219
220 ump = MOUNTTOUNIONFSMOUNT(mp);
221 lkflags = (cnp ? cnp->cn_lkflags : 0);
222 path = (cnp ? cnp->cn_nameptr : NULL);
223 *vpp = NULLVP;
224
225 if (uppervp == NULLVP && lowervp == NULLVP)
226 panic("unionfs_nodeget: upper and lower is null");
227
228 vt = (uppervp != NULLVP ? uppervp->v_type : lowervp->v_type);
229
230 /* If it has no ISLASTCN flag, path check is skipped. */
231 if (cnp && !(cnp->cn_flags & ISLASTCN))
232 path = NULL;
233
234 /* check the cache */
235 if (path != NULL && dvp != NULLVP && vt == VDIR) {
236 vp = unionfs_get_cached_vnode(uppervp, lowervp, dvp, path);
237 if (vp != NULLVP) {
238 vref(vp);
239 *vpp = vp;
240 goto unionfs_nodeget_out;
241 }
242 }
243
244 if ((uppervp == NULLVP || ump->um_uppervp != uppervp) ||
245 (lowervp == NULLVP || ump->um_lowervp != lowervp)) {
246 /* dvp will be NULLVP only in case of root vnode. */
247 if (dvp == NULLVP)
248 return (EINVAL);
249 }
250
251 /*
252 * Do the MALLOC before the getnewvnode since doing so afterward
253 * might cause a bogus v_data pointer to get dereferenced elsewhere
254 * if MALLOC should block.
255 */
256 unp = malloc(sizeof(struct unionfs_node),
257 M_UNIONFSNODE, M_WAITOK | M_ZERO);
258
259 error = getnewvnode("unionfs", mp, &unionfs_vnodeops, &vp);
260 if (error != 0) {
261 free(unp, M_UNIONFSNODE);
262 return (error);
263 }
264 error = insmntque(vp, mp); /* XXX: Too early for mpsafe fs */
265 if (error != 0) {
266 free(unp, M_UNIONFSNODE);
267 return (error);
268 }
269 if (dvp != NULLVP)
270 vref(dvp);
271 if (uppervp != NULLVP)
272 vref(uppervp);
273 if (lowervp != NULLVP)
274 vref(lowervp);
275
276 if (vt == VDIR)
277 unp->un_hashtbl = hashinit(NUNIONFSNODECACHE, M_UNIONFSHASH,
278 &(unp->un_hashmask));
279
280 unp->un_vnode = vp;
281 unp->un_uppervp = uppervp;
282 unp->un_lowervp = lowervp;
283 unp->un_dvp = dvp;
284 if (uppervp != NULLVP)
285 vp->v_vnlock = uppervp->v_vnlock;
286 else
287 vp->v_vnlock = lowervp->v_vnlock;
288
289 if (path != NULL) {
290 unp->un_path = (char *)
291 malloc(cnp->cn_namelen +1, M_UNIONFSPATH, M_WAITOK|M_ZERO);
292 bcopy(cnp->cn_nameptr, unp->un_path, cnp->cn_namelen);
293 unp->un_path[cnp->cn_namelen] = '\0';
294 }
295 vp->v_type = vt;
296 vp->v_data = unp;
297
298 if ((uppervp != NULLVP && ump->um_uppervp == uppervp) &&
299 (lowervp != NULLVP && ump->um_lowervp == lowervp))
300 vp->v_vflag |= VV_ROOT;
301
302 if (path != NULL && dvp != NULLVP && vt == VDIR)
303 *vpp = unionfs_ins_cached_vnode(unp, dvp, path);
304 if ((*vpp) != NULLVP) {
305 if (dvp != NULLVP)
306 vrele(dvp);
307 if (uppervp != NULLVP)
308 vrele(uppervp);
309 if (lowervp != NULLVP)
310 vrele(lowervp);
311
312 unp->un_uppervp = NULLVP;
313 unp->un_lowervp = NULLVP;
314 unp->un_dvp = NULLVP;
315 vrele(vp);
316 vp = *vpp;
317 vref(vp);
318 } else
319 *vpp = vp;
320
321unionfs_nodeget_out:
322 if (lkflags & LK_TYPE_MASK)
323 vn_lock(vp, lkflags | LK_RETRY);
324
325 return (0);
326}
327
328/*
329 * Clean up the unionfs node.
330 */
331void
332unionfs_noderem(struct vnode *vp, struct thread *td)
333{
334 int vfslocked;
335 int count;
336 struct unionfs_node *unp, *unp_t1, *unp_t2;
337 struct unionfs_node_hashhead *hd;
338 struct unionfs_node_status *unsp, *unsp_tmp;
339 struct vnode *lvp;
340 struct vnode *uvp;
341 struct vnode *dvp;
342
343 /*
344 * Use the interlock to protect the clearing of v_data to
345 * prevent faults in unionfs_lock().
346 */
347 VI_LOCK(vp);
348 unp = VTOUNIONFS(vp);
349 lvp = unp->un_lowervp;
350 uvp = unp->un_uppervp;
351 dvp = unp->un_dvp;
352 unp->un_lowervp = unp->un_uppervp = NULLVP;
353
354 vp->v_vnlock = &(vp->v_lock);
355 vp->v_data = NULL;
356 lockmgr(vp->v_vnlock, LK_EXCLUSIVE | LK_INTERLOCK, VI_MTX(vp));
357 if (lvp != NULLVP)
358 VOP_UNLOCK(lvp, 0);
359 if (uvp != NULLVP)
360 VOP_UNLOCK(uvp, 0);
361 vp->v_object = NULL;
362
363 if (dvp != NULLVP && unp->un_hash.le_prev != NULL)
364 unionfs_rem_cached_vnode(unp, dvp);
365
366 if (lvp != NULLVP) {
367 vfslocked = VFS_LOCK_GIANT(lvp->v_mount);
368 vrele(lvp);
369 VFS_UNLOCK_GIANT(vfslocked);
370 }
371 if (uvp != NULLVP) {
372 vfslocked = VFS_LOCK_GIANT(uvp->v_mount);
373 vrele(uvp);
374 VFS_UNLOCK_GIANT(vfslocked);
375 }
376 if (dvp != NULLVP) {
377 vfslocked = VFS_LOCK_GIANT(dvp->v_mount);
378 vrele(dvp);
379 VFS_UNLOCK_GIANT(vfslocked);
380 unp->un_dvp = NULLVP;
381 }
382 if (unp->un_path != NULL) {
383 free(unp->un_path, M_UNIONFSPATH);
384 unp->un_path = NULL;
385 }
386
387 if (unp->un_hashtbl != NULL) {
388 for (count = 0; count <= unp->un_hashmask; count++) {
389 hd = unp->un_hashtbl + count;
390 LIST_FOREACH_SAFE(unp_t1, hd, un_hash, unp_t2) {
391 LIST_REMOVE(unp_t1, un_hash);
392 unp_t1->un_hash.le_next = NULL;
393 unp_t1->un_hash.le_prev = NULL;
394 }
395 }
396 hashdestroy(unp->un_hashtbl, M_UNIONFSHASH, unp->un_hashmask);
397 }
398
399 LIST_FOREACH_SAFE(unsp, &(unp->un_unshead), uns_list, unsp_tmp) {
400 LIST_REMOVE(unsp, uns_list);
401 free(unsp, M_TEMP);
402 }
403 free(unp, M_UNIONFSNODE);
404}
405
406/*
407 * Get the unionfs node status.
408 * You need exclusive lock this vnode.
409 */
410void
411unionfs_get_node_status(struct unionfs_node *unp, struct thread *td,
412 struct unionfs_node_status **unspp)
413{
414 struct unionfs_node_status *unsp;
415 pid_t pid = td->td_proc->p_pid;
416
417 KASSERT(NULL != unspp, ("null pointer"));
418 ASSERT_VOP_ELOCKED(UNIONFSTOV(unp), "unionfs_get_node_status");
419
420 LIST_FOREACH(unsp, &(unp->un_unshead), uns_list) {
421 if (unsp->uns_pid == pid) {
422 *unspp = unsp;
423 return;
424 }
425 }
426
427 /* create a new unionfs node status */
428 unsp = malloc(sizeof(struct unionfs_node_status),
429 M_TEMP, M_WAITOK | M_ZERO);
430
431 unsp->uns_pid = pid;
432 LIST_INSERT_HEAD(&(unp->un_unshead), unsp, uns_list);
433
434 *unspp = unsp;
435}
436
437/*
438 * Remove the unionfs node status, if you can.
439 * You need exclusive lock this vnode.
440 */
441void
442unionfs_tryrem_node_status(struct unionfs_node *unp,
443 struct unionfs_node_status *unsp)
444{
445 KASSERT(NULL != unsp, ("null pointer"));
446 ASSERT_VOP_ELOCKED(UNIONFSTOV(unp), "unionfs_get_node_status");
447
448 if (0 < unsp->uns_lower_opencnt || 0 < unsp->uns_upper_opencnt)
449 return;
450
451 LIST_REMOVE(unsp, uns_list);
452 free(unsp, M_TEMP);
453}
454
455/*
456 * Create upper node attr.
457 */
458void
459unionfs_create_uppervattr_core(struct unionfs_mount *ump,
460 struct vattr *lva,
461 struct vattr *uva,
462 struct thread *td)
463{
464 VATTR_NULL(uva);
465 uva->va_type = lva->va_type;
466 uva->va_atime = lva->va_atime;
467 uva->va_mtime = lva->va_mtime;
468 uva->va_ctime = lva->va_ctime;
469
470 switch (ump->um_copymode) {
471 case UNIONFS_TRANSPARENT:
472 uva->va_mode = lva->va_mode;
473 uva->va_uid = lva->va_uid;
474 uva->va_gid = lva->va_gid;
475 break;
476 case UNIONFS_MASQUERADE:
477 if (ump->um_uid == lva->va_uid) {
478 uva->va_mode = lva->va_mode & 077077;
479 uva->va_mode |= (lva->va_type == VDIR ? ump->um_udir : ump->um_ufile) & 0700;
480 uva->va_uid = lva->va_uid;
481 uva->va_gid = lva->va_gid;
482 } else {
483 uva->va_mode = (lva->va_type == VDIR ? ump->um_udir : ump->um_ufile);
484 uva->va_uid = ump->um_uid;
485 uva->va_gid = ump->um_gid;
486 }
487 break;
488 default: /* UNIONFS_TRADITIONAL */
489 FILEDESC_SLOCK(td->td_proc->p_fd);
490 uva->va_mode = 0777 & ~td->td_proc->p_fd->fd_cmask;
491 FILEDESC_SUNLOCK(td->td_proc->p_fd);
492 uva->va_uid = ump->um_uid;
493 uva->va_gid = ump->um_gid;
494 break;
495 }
496}
497
498/*
499 * Create upper node attr.
500 */
501int
502unionfs_create_uppervattr(struct unionfs_mount *ump,
503 struct vnode *lvp,
504 struct vattr *uva,
505 struct ucred *cred,
506 struct thread *td)
507{
508 int error;
509 struct vattr lva;
510
511 if ((error = VOP_GETATTR(lvp, &lva, cred)))
512 return (error);
513
514 unionfs_create_uppervattr_core(ump, &lva, uva, td);
515
516 return (error);
517}
518
519/*
520 * relookup
521 *
522 * dvp should be locked on entry and will be locked on return.
523 *
524 * If an error is returned, *vpp will be invalid, otherwise it will hold a
525 * locked, referenced vnode. If *vpp == dvp then remember that only one
526 * LK_EXCLUSIVE lock is held.
527 */
528int
529unionfs_relookup(struct vnode *dvp, struct vnode **vpp,
530 struct componentname *cnp, struct componentname *cn,
531 struct thread *td, char *path, int pathlen, u_long nameiop)
532{
533 int error;
534
535 cn->cn_namelen = pathlen;
536 cn->cn_pnbuf = uma_zalloc(namei_zone, M_WAITOK);
537 bcopy(path, cn->cn_pnbuf, pathlen);
538 cn->cn_pnbuf[pathlen] = '\0';
539
540 cn->cn_nameiop = nameiop;
541 cn->cn_flags = (LOCKPARENT | LOCKLEAF | HASBUF | SAVENAME | ISLASTCN);
542 cn->cn_lkflags = LK_EXCLUSIVE;
543 cn->cn_thread = td;
544 cn->cn_cred = cnp->cn_cred;
545
546 cn->cn_nameptr = cn->cn_pnbuf;
547 cn->cn_consume = cnp->cn_consume;
548
549 if (nameiop == DELETE)
550 cn->cn_flags |= (cnp->cn_flags & (DOWHITEOUT | SAVESTART));
551 else if (RENAME == nameiop)
552 cn->cn_flags |= (cnp->cn_flags & SAVESTART);
553
554 vref(dvp);
555 VOP_UNLOCK(dvp, 0);
556
557 if ((error = relookup(dvp, vpp, cn))) {
558 uma_zfree(namei_zone, cn->cn_pnbuf);
559 cn->cn_flags &= ~HASBUF;
560 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
561 } else
562 vrele(dvp);
563
564 return (error);
565}
566
567/*
568 * relookup for CREATE namei operation.
569 *
570 * dvp is unionfs vnode. dvp should be locked.
571 *
572 * If it called 'unionfs_copyfile' function by unionfs_link etc,
573 * VOP_LOOKUP information is broken.
574 * So it need relookup in order to create link etc.
575 */
576int
577unionfs_relookup_for_create(struct vnode *dvp, struct componentname *cnp,
578 struct thread *td)
579{
580 int error;
581 struct vnode *udvp;
582 struct vnode *vp;
583 struct componentname cn;
584
585 udvp = UNIONFSVPTOUPPERVP(dvp);
586 vp = NULLVP;
587
588 error = unionfs_relookup(udvp, &vp, cnp, &cn, td, cnp->cn_nameptr,
589 strlen(cnp->cn_nameptr), CREATE);
590 if (error)
591 return (error);
592
593 if (vp != NULLVP) {
594 if (udvp == vp)
595 vrele(vp);
596 else
597 vput(vp);
598
599 error = EEXIST;
600 }
601
602 if (cn.cn_flags & HASBUF) {
603 uma_zfree(namei_zone, cn.cn_pnbuf);
604 cn.cn_flags &= ~HASBUF;
605 }
606
607 if (!error) {
608 cn.cn_flags |= (cnp->cn_flags & HASBUF);
609 cnp->cn_flags = cn.cn_flags;
610 }
611
612 return (error);
613}
614
615/*
616 * relookup for DELETE namei operation.
617 *
618 * dvp is unionfs vnode. dvp should be locked.
619 */
620int
621unionfs_relookup_for_delete(struct vnode *dvp, struct componentname *cnp,
622 struct thread *td)
623{
624 int error;
625 struct vnode *udvp;
626 struct vnode *vp;
627 struct componentname cn;
628
629 udvp = UNIONFSVPTOUPPERVP(dvp);
630 vp = NULLVP;
631
632 error = unionfs_relookup(udvp, &vp, cnp, &cn, td, cnp->cn_nameptr,
633 strlen(cnp->cn_nameptr), DELETE);
634 if (error)
635 return (error);
636
637 if (vp == NULLVP)
638 error = ENOENT;
639 else {
640 if (udvp == vp)
641 vrele(vp);
642 else
643 vput(vp);
644 }
645
646 if (cn.cn_flags & HASBUF) {
647 uma_zfree(namei_zone, cn.cn_pnbuf);
648 cn.cn_flags &= ~HASBUF;
649 }
650
651 if (!error) {
652 cn.cn_flags |= (cnp->cn_flags & HASBUF);
653 cnp->cn_flags = cn.cn_flags;
654 }
655
656 return (error);
657}
658
659/*
660 * relookup for RENAME namei operation.
661 *
662 * dvp is unionfs vnode. dvp should be locked.
663 */
664int
665unionfs_relookup_for_rename(struct vnode *dvp, struct componentname *cnp,
666 struct thread *td)
667{
668 int error;
669 struct vnode *udvp;
670 struct vnode *vp;
671 struct componentname cn;
672
673 udvp = UNIONFSVPTOUPPERVP(dvp);
674 vp = NULLVP;
675
676 error = unionfs_relookup(udvp, &vp, cnp, &cn, td, cnp->cn_nameptr,
677 strlen(cnp->cn_nameptr), RENAME);
678 if (error)
679 return (error);
680
681 if (vp != NULLVP) {
682 if (udvp == vp)
683 vrele(vp);
684 else
685 vput(vp);
686 }
687
688 if (cn.cn_flags & HASBUF) {
689 uma_zfree(namei_zone, cn.cn_pnbuf);
690 cn.cn_flags &= ~HASBUF;
691 }
692
693 if (!error) {
694 cn.cn_flags |= (cnp->cn_flags & HASBUF);
695 cnp->cn_flags = cn.cn_flags;
696 }
697
698 return (error);
699
700}
701
702/*
703 * Update the unionfs_node.
704 *
705 * uvp is new locked upper vnode. unionfs vnode's lock will be exchanged to the
706 * uvp's lock and lower's lock will be unlocked.
707 */
708static void
709unionfs_node_update(struct unionfs_node *unp, struct vnode *uvp,
710 struct thread *td)
711{
712 unsigned count, lockrec;
713 struct vnode *vp;
714 struct vnode *lvp;
715 struct vnode *dvp;
716
717 vp = UNIONFSTOV(unp);
718 lvp = unp->un_lowervp;
719 ASSERT_VOP_ELOCKED(lvp, "unionfs_node_update");
720 dvp = unp->un_dvp;
721
722 /*
723 * lock update
724 */
725 VI_LOCK(vp);
726 unp->un_uppervp = uvp;
727 vp->v_vnlock = uvp->v_vnlock;
728 VI_UNLOCK(vp);
729 lockrec = lvp->v_vnlock->lk_recurse;
730 for (count = 0; count < lockrec; count++)
731 vn_lock(uvp, LK_EXCLUSIVE | LK_CANRECURSE | LK_RETRY);
732
733 /*
734 * cache update
735 */
736 if (unp->un_path != NULL && dvp != NULLVP && vp->v_type == VDIR) {
737 static struct unionfs_node_hashhead *hd;
738
739 VI_LOCK(dvp);
740 hd = unionfs_get_hashhead(dvp, unp->un_path);
741 LIST_REMOVE(unp, un_hash);
742 LIST_INSERT_HEAD(hd, unp, un_hash);
743 VI_UNLOCK(dvp);
744 }
745}
746
747/*
748 * Create a new shadow dir.
749 *
750 * udvp should be locked on entry and will be locked on return.
751 *
752 * If no error returned, unp will be updated.
753 */
754int
755unionfs_mkshadowdir(struct unionfs_mount *ump, struct vnode *udvp,
756 struct unionfs_node *unp, struct componentname *cnp,
757 struct thread *td)
758{
759 int error;
760 struct vnode *lvp;
761 struct vnode *uvp;
762 struct vattr va;
763 struct vattr lva;
764 struct componentname cn;
765 struct mount *mp;
766 struct ucred *cred;
767 struct ucred *credbk;
768 struct uidinfo *rootinfo;
769
770 if (unp->un_uppervp != NULLVP)
771 return (EEXIST);
772
773 lvp = unp->un_lowervp;
774 uvp = NULLVP;
775 credbk = cnp->cn_cred;
776
777 /* Authority change to root */
778 rootinfo = uifind((uid_t)0);
779 cred = crdup(cnp->cn_cred);
780 chgproccnt(cred->cr_ruidinfo, 1, 0);
781 change_euid(cred, rootinfo);
782 change_ruid(cred, rootinfo);
783 change_svuid(cred, (uid_t)0);
784 uifree(rootinfo);
785 cnp->cn_cred = cred;
786
787 memset(&cn, 0, sizeof(cn));
788
789 if ((error = VOP_GETATTR(lvp, &lva, cnp->cn_cred)))
790 goto unionfs_mkshadowdir_abort;
791
792 if ((error = unionfs_relookup(udvp, &uvp, cnp, &cn, td, cnp->cn_nameptr, cnp->cn_namelen, CREATE)))
793 goto unionfs_mkshadowdir_abort;
794 if (uvp != NULLVP) {
795 if (udvp == uvp)
796 vrele(uvp);
797 else
798 vput(uvp);
799
800 error = EEXIST;
801 goto unionfs_mkshadowdir_free_out;
802 }
803
804 if ((error = vn_start_write(udvp, &mp, V_WAIT | PCATCH)))
805 goto unionfs_mkshadowdir_free_out;
806 unionfs_create_uppervattr_core(ump, &lva, &va, td);
807
808 error = VOP_MKDIR(udvp, &uvp, &cn, &va);
809
810 if (!error) {
811 unionfs_node_update(unp, uvp, td);
812
813 /*
814 * XXX The bug which cannot set uid/gid was corrected.
815 * Ignore errors.
816 */
817 va.va_type = VNON;
818 VOP_SETATTR(uvp, &va, cn.cn_cred);
819 }
820 vn_finished_write(mp);
821
822unionfs_mkshadowdir_free_out:
823 if (cn.cn_flags & HASBUF) {
824 uma_zfree(namei_zone, cn.cn_pnbuf);
825 cn.cn_flags &= ~HASBUF;
826 }
827
828unionfs_mkshadowdir_abort:
829 cnp->cn_cred = credbk;
830 chgproccnt(cred->cr_ruidinfo, -1, 0);
831 crfree(cred);
832
833 return (error);
834}
835
836/*
837 * Create a new whiteout.
838 *
839 * dvp should be locked on entry and will be locked on return.
840 */
841int
842unionfs_mkwhiteout(struct vnode *dvp, struct componentname *cnp,
843 struct thread *td, char *path)
844{
845 int error;
846 struct vnode *wvp;
847 struct componentname cn;
848 struct mount *mp;
849
850 if (path == NULL)
851 path = cnp->cn_nameptr;
852
853 wvp = NULLVP;
854 if ((error = unionfs_relookup(dvp, &wvp, cnp, &cn, td, path, strlen(path), CREATE)))
855 return (error);
856 if (wvp != NULLVP) {
857 if (cn.cn_flags & HASBUF) {
858 uma_zfree(namei_zone, cn.cn_pnbuf);
859 cn.cn_flags &= ~HASBUF;
860 }
861 if (dvp == wvp)
862 vrele(wvp);
863 else
864 vput(wvp);
865
866 return (EEXIST);
867 }
868
869 if ((error = vn_start_write(dvp, &mp, V_WAIT | PCATCH)))
870 goto unionfs_mkwhiteout_free_out;
871 error = VOP_WHITEOUT(dvp, &cn, CREATE);
872
873 vn_finished_write(mp);
874
875unionfs_mkwhiteout_free_out:
876 if (cn.cn_flags & HASBUF) {
877 uma_zfree(namei_zone, cn.cn_pnbuf);
878 cn.cn_flags &= ~HASBUF;
879 }
880
881 return (error);
882}
883
884/*
885 * Create a new vnode for create a new shadow file.
886 *
887 * If an error is returned, *vpp will be invalid, otherwise it will hold a
888 * locked, referenced and opened vnode.
889 *
890 * unp is never updated.
891 */
892static int
893unionfs_vn_create_on_upper(struct vnode **vpp, struct vnode *udvp,
894 struct unionfs_node *unp, struct vattr *uvap,
895 struct thread *td)
896{
897 struct unionfs_mount *ump;
898 struct vnode *vp;
899 struct vnode *lvp;
900 struct ucred *cred;
901 struct vattr lva;
902 int fmode;
903 int error;
904 struct componentname cn;
905
906 ump = MOUNTTOUNIONFSMOUNT(UNIONFSTOV(unp)->v_mount);
907 vp = NULLVP;
908 lvp = unp->un_lowervp;
909 cred = td->td_ucred;
910 fmode = FFLAGS(O_WRONLY | O_CREAT | O_TRUNC | O_EXCL);
911 error = 0;
912
913 if ((error = VOP_GETATTR(lvp, &lva, cred)) != 0)
914 return (error);
915 unionfs_create_uppervattr_core(ump, &lva, uvap, td);
916
917 if (unp->un_path == NULL)
918 panic("unionfs: un_path is null");
919
920 cn.cn_namelen = strlen(unp->un_path);
921 cn.cn_pnbuf = uma_zalloc(namei_zone, M_WAITOK);
922 bcopy(unp->un_path, cn.cn_pnbuf, cn.cn_namelen + 1);
923 cn.cn_nameiop = CREATE;
924 cn.cn_flags = (LOCKPARENT | LOCKLEAF | HASBUF | SAVENAME | ISLASTCN);
925 cn.cn_lkflags = LK_EXCLUSIVE;
926 cn.cn_thread = td;
927 cn.cn_cred = cred;
928 cn.cn_nameptr = cn.cn_pnbuf;
929 cn.cn_consume = 0;
930
931 vref(udvp);
932 if ((error = relookup(udvp, &vp, &cn)) != 0)
933 goto unionfs_vn_create_on_upper_free_out2;
934 vrele(udvp);
935
936 if (vp != NULLVP) {
937 if (vp == udvp)
938 vrele(vp);
939 else
940 vput(vp);
941 error = EEXIST;
942 goto unionfs_vn_create_on_upper_free_out1;
943 }
944
945 if ((error = VOP_CREATE(udvp, &vp, &cn, uvap)) != 0)
946 goto unionfs_vn_create_on_upper_free_out1;
947
948 if ((error = VOP_OPEN(vp, fmode, cred, td, NULL)) != 0) {
949 vput(vp);
950 goto unionfs_vn_create_on_upper_free_out1;
951 }
952 vp->v_writecount++;
953 *vpp = vp;
954
955unionfs_vn_create_on_upper_free_out1:
956 VOP_UNLOCK(udvp, 0);
957
958unionfs_vn_create_on_upper_free_out2:
959 if (cn.cn_flags & HASBUF) {
960 uma_zfree(namei_zone, cn.cn_pnbuf);
961 cn.cn_flags &= ~HASBUF;
962 }
963
964 return (error);
965}
966
967/*
968 * Copy from lvp to uvp.
969 *
970 * lvp and uvp should be locked and opened on entry and will be locked and
971 * opened on return.
972 */
973static int
974unionfs_copyfile_core(struct vnode *lvp, struct vnode *uvp,
975 struct ucred *cred, struct thread *td)
976{
977 int error;
978 off_t offset;
979 int count;
980 int bufoffset;
981 char *buf;
982 struct uio uio;
983 struct iovec iov;
984
985 error = 0;
986 memset(&uio, 0, sizeof(uio));
987
988 uio.uio_td = td;
989 uio.uio_segflg = UIO_SYSSPACE;
990 uio.uio_offset = 0;
991
992 buf = malloc(MAXBSIZE, M_TEMP, M_WAITOK);
993
994 while (error == 0) {
995 offset = uio.uio_offset;
996
997 uio.uio_iov = &iov;
998 uio.uio_iovcnt = 1;
999 iov.iov_base = buf;
1000 iov.iov_len = MAXBSIZE;
1001 uio.uio_resid = iov.iov_len;
1002 uio.uio_rw = UIO_READ;
1003
1004 if ((error = VOP_READ(lvp, &uio, 0, cred)) != 0)
1005 break;
1006 if ((count = MAXBSIZE - uio.uio_resid) == 0)
1007 break;
1008
1009 bufoffset = 0;
1010 while (bufoffset < count) {
1011 uio.uio_iov = &iov;
1012 uio.uio_iovcnt = 1;
1013 iov.iov_base = buf + bufoffset;
1014 iov.iov_len = count - bufoffset;
1015 uio.uio_offset = offset + bufoffset;
1016 uio.uio_resid = iov.iov_len;
1017 uio.uio_rw = UIO_WRITE;
1018
1019 if ((error = VOP_WRITE(uvp, &uio, 0, cred)) != 0)
1020 break;
1021
1022 bufoffset += (count - bufoffset) - uio.uio_resid;
1023 }
1024
1025 uio.uio_offset = offset + bufoffset;
1026 }
1027
1028 free(buf, M_TEMP);
1029
1030 return (error);
1031}
1032
1033/*
1034 * Copy file from lower to upper.
1035 *
1036 * If you need copy of the contents, set 1 to docopy. Otherwise, set 0 to
1037 * docopy.
1038 *
1039 * If no error returned, unp will be updated.
1040 */
1041int
1042unionfs_copyfile(struct unionfs_node *unp, int docopy, struct ucred *cred,
1043 struct thread *td)
1044{
1045 int error;
1046 struct mount *mp;
1047 struct vnode *udvp;
1048 struct vnode *lvp;
1049 struct vnode *uvp;
1050 struct vattr uva;
1051
1052 lvp = unp->un_lowervp;
1053 uvp = NULLVP;
1054
1055 if ((UNIONFSTOV(unp)->v_mount->mnt_flag & MNT_RDONLY))
1056 return (EROFS);
1057 if (unp->un_dvp == NULLVP)
1058 return (EINVAL);
1059 if (unp->un_uppervp != NULLVP)
1060 return (EEXIST);
1061 udvp = VTOUNIONFS(unp->un_dvp)->un_uppervp;
1062 if (udvp == NULLVP)
1063 return (EROFS);
1064 if ((udvp->v_mount->mnt_flag & MNT_RDONLY))
1065 return (EROFS);
1066
1067 error = VOP_ACCESS(lvp, VREAD, cred, td);
1068 if (error != 0)
1069 return (error);
1070
1071 if ((error = vn_start_write(udvp, &mp, V_WAIT | PCATCH)) != 0)
1072 return (error);
1073 error = unionfs_vn_create_on_upper(&uvp, udvp, unp, &uva, td);
1074 if (error != 0) {
1075 vn_finished_write(mp);
1076 return (error);
1077 }
1078
1079 if (docopy != 0) {
1080 error = VOP_OPEN(lvp, FREAD, cred, td, NULL);
1081 if (error == 0) {
1082 error = unionfs_copyfile_core(lvp, uvp, cred, td);
1083 VOP_CLOSE(lvp, FREAD, cred, td);
1084 }
1085 }
1086 VOP_CLOSE(uvp, FWRITE, cred, td);
1087 uvp->v_writecount--;
1088
1089 vn_finished_write(mp);
1090
1091 if (error == 0) {
1092 /* Reset the attributes. Ignore errors. */
1093 uva.va_type = VNON;
1094 VOP_SETATTR(uvp, &uva, cred);
1095 }
1096
1097 unionfs_node_update(unp, uvp, td);
1098
1099 return (error);
1100}
1101
1102/*
1103 * It checks whether vp can rmdir. (check empty)
1104 *
1105 * vp is unionfs vnode.
1106 * vp should be locked.
1107 */
1108int
1109unionfs_check_rmdir(struct vnode *vp, struct ucred *cred, struct thread *td)
1110{
1111 int error;
1112 int eofflag;
1113 int lookuperr;
1114 struct vnode *uvp;
1115 struct vnode *lvp;
1116 struct vnode *tvp;
1117 struct vattr va;
1118 struct componentname cn;
1119 /*
1120 * The size of buf needs to be larger than DIRBLKSIZ.
1121 */
1122 char buf[256 * 6];
1123 struct dirent *dp;
1124 struct dirent *edp;
1125 struct uio uio;
1126 struct iovec iov;
1127
1128 ASSERT_VOP_ELOCKED(vp, "unionfs_check_rmdir");
1129
1130 eofflag = 0;
1131 uvp = UNIONFSVPTOUPPERVP(vp);
1132 lvp = UNIONFSVPTOLOWERVP(vp);
1133
1134 /* check opaque */
1135 if ((error = VOP_GETATTR(uvp, &va, cred)) != 0)
1136 return (error);
1137 if (va.va_flags & OPAQUE)
1138 return (0);
1139
1140 /* open vnode */
1141#ifdef MAC
1142 if ((error = mac_vnode_check_open(cred, vp, VEXEC|VREAD)) != 0)
1143 return (error);
1144#endif
1145 if ((error = VOP_ACCESS(vp, VEXEC|VREAD, cred, td)) != 0)
1146 return (error);
1147 if ((error = VOP_OPEN(vp, FREAD, cred, td, NULL)) != 0)
1148 return (error);
1149
1150 uio.uio_rw = UIO_READ;
1151 uio.uio_segflg = UIO_SYSSPACE;
1152 uio.uio_td = td;
1153 uio.uio_offset = 0;
1154
1155#ifdef MAC
1156 error = mac_vnode_check_readdir(td->td_ucred, lvp);
1157#endif
1158 while (!error && !eofflag) {
1159 iov.iov_base = buf;
1160 iov.iov_len = sizeof(buf);
1161 uio.uio_iov = &iov;
1162 uio.uio_iovcnt = 1;
1163 uio.uio_resid = iov.iov_len;
1164
1165 error = VOP_READDIR(lvp, &uio, cred, &eofflag, NULL, NULL);
1166 if (error != 0)
1167 break;
1168 if (eofflag == 0 && uio.uio_resid == sizeof(buf)) {
1169#ifdef DIAGNOSTIC
1170 panic("bad readdir response from lower FS.");
1171#endif
1172 break;
1173 }
1174
1175 edp = (struct dirent*)&buf[sizeof(buf) - uio.uio_resid];
1176 for (dp = (struct dirent*)buf; !error && dp < edp;
1177 dp = (struct dirent*)((caddr_t)dp + dp->d_reclen)) {
1178 if (dp->d_type == DT_WHT ||
1179 (dp->d_namlen == 1 && dp->d_name[0] == '.') ||
1180 (dp->d_namlen == 2 && !bcmp(dp->d_name, "..", 2)))
1181 continue;
1182
1183 cn.cn_namelen = dp->d_namlen;
1184 cn.cn_pnbuf = NULL;
1185 cn.cn_nameptr = dp->d_name;
1186 cn.cn_nameiop = LOOKUP;
1187 cn.cn_flags = (LOCKPARENT | LOCKLEAF | SAVENAME | RDONLY | ISLASTCN);
1188 cn.cn_lkflags = LK_EXCLUSIVE;
1189 cn.cn_thread = td;
1190 cn.cn_cred = cred;
1191 cn.cn_consume = 0;
1192
1193 /*
1194 * check entry in lower.
1195 * Sometimes, readdir function returns
1196 * wrong entry.
1197 */
1198 lookuperr = VOP_LOOKUP(lvp, &tvp, &cn);
1199
1200 if (!lookuperr)
1201 vput(tvp);
1202 else
1203 continue; /* skip entry */
1204
1205 /*
1206 * check entry
1207 * If it has no exist/whiteout entry in upper,
1208 * directory is not empty.
1209 */
1210 cn.cn_flags = (LOCKPARENT | LOCKLEAF | SAVENAME | RDONLY | ISLASTCN);
1211 lookuperr = VOP_LOOKUP(uvp, &tvp, &cn);
1212
1213 if (!lookuperr)
1214 vput(tvp);
1215
1216 /* ignore exist or whiteout entry */
1217 if (!lookuperr ||
1218 (lookuperr == ENOENT && (cn.cn_flags & ISWHITEOUT)))
1219 continue;
1220
1221 error = ENOTEMPTY;
1222 }
1223 }
1224
1225 /* close vnode */
1226 VOP_CLOSE(vp, FREAD, cred, td);
1227
1228 return (error);
1229}
1230
1231#ifdef DIAGNOSTIC
1232
1233struct vnode *
1234unionfs_checkuppervp(struct vnode *vp, char *fil, int lno)
1235{
1236 struct unionfs_node *unp;
1237
1238 unp = VTOUNIONFS(vp);
1239
1240#ifdef notyet
1241 if (vp->v_op != unionfs_vnodeop_p) {
1242 printf("unionfs_checkuppervp: on non-unionfs-node.\n");
1243#ifdef KDB
1244 kdb_enter(KDB_WHY_UNIONFS,
1245 "unionfs_checkuppervp: on non-unionfs-node.\n");
1246#endif
1247 panic("unionfs_checkuppervp");
1248 };
1249#endif
1250 return (unp->un_uppervp);
1251}
1252
1253struct vnode *
1254unionfs_checklowervp(struct vnode *vp, char *fil, int lno)
1255{
1256 struct unionfs_node *unp;
1257
1258 unp = VTOUNIONFS(vp);
1259
1260#ifdef notyet
1261 if (vp->v_op != unionfs_vnodeop_p) {
1262 printf("unionfs_checklowervp: on non-unionfs-node.\n");
1263#ifdef KDB
1264 kdb_enter(KDB_WHY_UNIONFS,
1265 "unionfs_checklowervp: on non-unionfs-node.\n");
1266#endif
1267 panic("unionfs_checklowervp");
1268 };
1269#endif
1270 return (unp->un_lowervp);
1271}
1272#endif