2 * Copyright (c) 1992, 1993, 1994, 1995 Jan-Simon Pendry.
3 * Copyright (c) 1992, 1993, 1994, 1995
4 * The Regents of the University of California. All rights reserved.
6 * This code is derived from software contributed to Berkeley by
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10 * modification, are permitted provided that the following conditions
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13 * notice, this list of conditions and the following disclaimer.
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19 * This product includes software developed by the University of
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21 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
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34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * @(#)union_vnops.c 8.32 (Berkeley) 6/23/95
38 * $FreeBSD: src/sys/miscfs/union/union_vnops.c,v 1.72 1999/12/15 23:02:14 eivind Exp $
39 * $DragonFly: src/sys/vfs/union/union_vnops.c,v 1.12 2004/05/20 05:09:18 cpressey Exp $
42 #include <sys/param.h>
43 #include <sys/systm.h>
45 #include <sys/fcntl.h>
47 #include <sys/kernel.h>
48 #include <sys/vnode.h>
49 #include <sys/mount.h>
50 #include <sys/namei.h>
51 #include <sys/malloc.h>
54 #include <sys/sysctl.h>
58 #include <vm/vnode_pager.h>
60 #include <vm/vm_page.h>
61 #include <vm/vm_object.h>
66 SYSCTL_INT(_vfs, OID_AUTO, uniondebug, CTLFLAG_RW, &uniondebug, 0, "");
68 SYSCTL_INT(_vfs, OID_AUTO, uniondebug, CTLFLAG_RD, &uniondebug, 0, "");
71 static int union_access (struct vop_access_args *ap);
72 static int union_advlock (struct vop_advlock_args *ap);
73 static int union_bmap (struct vop_bmap_args *ap);
74 static int union_close (struct vop_close_args *ap);
75 static int union_create (struct vop_create_args *ap);
76 static int union_fsync (struct vop_fsync_args *ap);
77 static int union_getattr (struct vop_getattr_args *ap);
78 static int union_inactive (struct vop_inactive_args *ap);
79 static int union_ioctl (struct vop_ioctl_args *ap);
80 static int union_lease (struct vop_lease_args *ap);
81 static int union_link (struct vop_link_args *ap);
82 static int union_lock (struct vop_lock_args *ap);
83 static int union_lookup (struct vop_lookup_args *ap);
84 static int union_lookup1 (struct vnode *udvp, struct vnode **dvp,
86 struct componentname *cnp);
87 static int union_mkdir (struct vop_mkdir_args *ap);
88 static int union_mknod (struct vop_mknod_args *ap);
89 static int union_mmap (struct vop_mmap_args *ap);
90 static int union_open (struct vop_open_args *ap);
91 static int union_pathconf (struct vop_pathconf_args *ap);
92 static int union_print (struct vop_print_args *ap);
93 static int union_read (struct vop_read_args *ap);
94 static int union_readdir (struct vop_readdir_args *ap);
95 static int union_readlink (struct vop_readlink_args *ap);
96 static int union_reclaim (struct vop_reclaim_args *ap);
97 static int union_remove (struct vop_remove_args *ap);
98 static int union_rename (struct vop_rename_args *ap);
99 static int union_revoke (struct vop_revoke_args *ap);
100 static int union_rmdir (struct vop_rmdir_args *ap);
101 static int union_poll (struct vop_poll_args *ap);
102 static int union_setattr (struct vop_setattr_args *ap);
103 static int union_strategy (struct vop_strategy_args *ap);
104 static int union_getpages (struct vop_getpages_args *ap);
105 static int union_putpages (struct vop_putpages_args *ap);
106 static int union_symlink (struct vop_symlink_args *ap);
107 static int union_unlock (struct vop_unlock_args *ap);
108 static int union_whiteout (struct vop_whiteout_args *ap);
109 static int union_write (struct vop_read_args *ap);
113 union_lock_upper(struct union_node *un, struct thread *td)
115 struct vnode *uppervp;
117 if ((uppervp = un->un_uppervp) != NULL) {
119 vn_lock(uppervp, NULL, LK_EXCLUSIVE | LK_CANRECURSE | LK_RETRY, td);
121 KASSERT((uppervp == NULL || uppervp->v_usecount > 0), ("uppervp usecount is 0"));
127 union_unlock_upper(struct vnode *uppervp, struct thread *td)
134 union_lock_other(struct union_node *un, struct thread *td)
138 if (un->un_uppervp != NULL) {
139 vp = union_lock_upper(un, td);
140 } else if ((vp = un->un_lowervp) != NULL) {
142 vn_lock(vp, NULL, LK_EXCLUSIVE | LK_CANRECURSE | LK_RETRY, td);
149 union_unlock_other(struct vnode *vp, struct thread *td)
157 * udvp must be exclusively locked on call and will remain
158 * exclusively locked on return. This is the mount point
159 * for out filesystem.
161 * dvp Our base directory, locked and referenced.
162 * The passed dvp will be dereferenced and unlocked on return
163 * and a new dvp will be returned which is locked and
164 * referenced in the same variable.
166 * vpp is filled in with the result if no error occured,
169 * If an error is returned, *vpp is set to NULLVP. If no
170 * error occurs, *vpp is returned with a reference and an
175 union_lookup1(struct vnode *udvp, struct vnode **pdvp, struct vnode **vpp,
176 struct componentname *cnp)
179 struct thread *td = cnp->cn_td;
180 struct vnode *dvp = *pdvp;
185 * If stepping up the directory tree, check for going
186 * back across the mount point, in which case do what
187 * lookup would do by stepping back down the mount
190 if (cnp->cn_flags & CNP_ISDOTDOT) {
191 while ((dvp != udvp) && (dvp->v_flag & VROOT)) {
193 * Don't do the NOCROSSMOUNT check
194 * at this level. By definition,
195 * union fs deals with namespaces, not
199 dvp = dvp->v_mount->mnt_vnodecovered;
202 vn_lock(dvp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
207 * Set return dvp to be the upperdvp 'parent directory.
212 * If the VOP_LOOKUP call generates an error, tdvp is invalid and no
213 * changes will have been made to dvp, so we are set to return.
216 error = VOP_LOOKUP(dvp, NCPNULL, &tdvp, NCPPNULL, cnp);
218 UDEBUG(("dvp %p error %d flags %lx\n", dvp, error, cnp->cn_flags));
224 * The parent directory will have been unlocked, unless lookup
225 * found the last component or if dvp == tdvp (tdvp must be locked).
227 * We want our dvp to remain locked and ref'd. We also want tdvp
228 * to remain locked and ref'd.
230 UDEBUG(("parentdir %p result %p flag %lx\n", dvp, tdvp, cnp->cn_flags));
232 if (dvp != tdvp && (cnp->cn_flags & CNP_ISLASTCN) == 0)
233 vn_lock(dvp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
236 * Lastly check if the current node is a mount point in
237 * which case walk up the mount hierarchy making sure not to
238 * bump into the root of the mount tree (ie. dvp != udvp).
240 * We use dvp as a temporary variable here, it is no longer related
241 * to the dvp above. However, we have to ensure that both *pdvp and
242 * tdvp are locked on return.
248 (dvp->v_type == VDIR) &&
249 (mp = dvp->v_mountedhere)
253 if (vfs_busy(mp, 0, NULL, td))
260 error = VFS_ROOT(mp, &dvp);
265 vn_lock(*pdvp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
277 * union_lookup(struct vnodeop_desc *a_desc, struct vnode *a_dvp,
278 * struct vnode **a_vpp, struct componentname *a_cnp)
281 union_lookup(struct vop_lookup_args *ap)
285 struct vnode *uppervp, *lowervp;
286 struct vnode *upperdvp, *lowerdvp;
287 struct vnode *dvp = ap->a_dvp; /* starting dir */
288 struct union_node *dun = VTOUNION(dvp); /* associated union node */
289 struct componentname *cnp = ap->a_cnp;
290 struct thread *td = cnp->cn_td;
291 int lockparent = cnp->cn_flags & CNP_LOCKPARENT;
292 struct union_mount *um = MOUNTTOUNIONMOUNT(dvp->v_mount);
293 struct ucred *saved_cred = NULL;
300 * Disallow write attemps to the filesystem mounted read-only.
302 if ((cnp->cn_flags & CNP_ISLASTCN) &&
303 (dvp->v_mount->mnt_flag & MNT_RDONLY) &&
304 (cnp->cn_nameiop == NAMEI_DELETE || cnp->cn_nameiop == NAMEI_RENAME)) {
309 * For any lookup's we do, always return with the parent locked
311 cnp->cn_flags |= CNP_LOCKPARENT;
313 lowerdvp = dun->un_lowervp;
322 * Get a private lock on uppervp and a reference, effectively
323 * taking it out of the union_node's control.
325 * We must lock upperdvp while holding our lock on dvp
326 * to avoid a deadlock.
328 upperdvp = union_lock_upper(dun, td);
331 * do the lookup in the upper level.
332 * if that level comsumes additional pathnames,
333 * then assume that something special is going
334 * on and just return that vnode.
336 if (upperdvp != NULLVP) {
338 * We do not have to worry about the DOTDOT case, we've
339 * already unlocked dvp.
341 UDEBUG(("A %p\n", upperdvp));
344 * Do the lookup. We must supply a locked and referenced
345 * upperdvp to the function and will get a new locked and
346 * referenced upperdvp back with the old having been
349 * If an error is returned, uppervp will be NULLVP. If no
350 * error occurs, uppervp will be the locked and referenced
351 * return vnode or possibly NULL, depending on what is being
352 * requested. It is possible that the returned uppervp
353 * will be the same as upperdvp.
355 uerror = union_lookup1(um->um_uppervp, &upperdvp, &uppervp, cnp);
357 "uerror %d upperdvp %p %d/%d, uppervp %p ref=%d/lck=%d\n",
360 upperdvp->v_usecount,
361 VOP_ISLOCKED(upperdvp, NULL),
363 (uppervp ? uppervp->v_usecount : -99),
364 (uppervp ? VOP_ISLOCKED(uppervp, NULL) : -99)
368 * Disallow write attemps to the filesystem mounted read-only.
370 if (uerror == EJUSTRETURN && (cnp->cn_flags & CNP_ISLASTCN) &&
371 (dvp->v_mount->mnt_flag & MNT_RDONLY) &&
372 (cnp->cn_nameiop == NAMEI_CREATE || cnp->cn_nameiop == NAMEI_RENAME)) {
378 * Special case. If cn_consume != 0 skip out. The result
379 * of the lookup is transfered to our return variable. If
380 * an error occured we have to throw away the results.
383 if (cnp->cn_consume != 0) {
384 if ((error = uerror) == 0) {
385 *ap->a_vpp = uppervp;
392 * Calculate whiteout, fall through
395 if (uerror == ENOENT || uerror == EJUSTRETURN) {
396 if (cnp->cn_flags & CNP_ISWHITEOUT) {
398 } else if (lowerdvp != NULLVP) {
401 terror = VOP_GETATTR(upperdvp, &va, cnp->cn_td);
402 if (terror == 0 && (va.va_flags & OPAQUE))
409 * in a similar way to the upper layer, do the lookup
410 * in the lower layer. this time, if there is some
411 * component magic going on, then vput whatever we got
412 * back from the upper layer and return the lower vnode
416 if (lowerdvp != NULLVP && !iswhiteout) {
419 UDEBUG(("B %p\n", lowerdvp));
422 * Force only LOOKUPs on the lower node, since
423 * we won't be making changes to it anyway.
425 nameiop = cnp->cn_nameiop;
426 cnp->cn_nameiop = NAMEI_LOOKUP;
427 if (um->um_op == UNMNT_BELOW) {
428 saved_cred = cnp->cn_cred;
429 cnp->cn_cred = um->um_cred;
433 * We shouldn't have to worry about locking interactions
434 * between the lower layer and our union layer (w.r.t.
435 * `..' processing) because we don't futz with lowervp
436 * locks in the union-node instantiation code path.
438 * union_lookup1() requires lowervp to be locked on entry,
439 * and it will be unlocked on return. The ref count will
440 * not change. On return lowervp doesn't represent anything
441 * to us so we NULL it out.
444 vn_lock(lowerdvp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
445 lerror = union_lookup1(um->um_lowervp, &lowerdvp, &lowervp, cnp);
446 if (lowerdvp == lowervp)
450 lowerdvp = NULL; /* lowerdvp invalid after vput */
452 if (um->um_op == UNMNT_BELOW)
453 cnp->cn_cred = saved_cred;
454 cnp->cn_nameiop = nameiop;
456 if (cnp->cn_consume != 0 || lerror == EACCES) {
457 if ((error = lerror) == 0) {
458 *ap->a_vpp = lowervp;
464 UDEBUG(("C %p\n", lowerdvp));
465 if ((cnp->cn_flags & CNP_ISDOTDOT) && dun->un_pvp != NULLVP) {
466 if ((lowervp = LOWERVP(dun->un_pvp)) != NULL) {
468 vn_lock(lowervp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
475 * Ok. Now we have uerror, uppervp, upperdvp, lerror, and lowervp.
477 * 1. If both layers returned an error, select the upper layer.
479 * 2. If the upper layer faile and the bottom layer succeeded,
480 * two subcases occur:
482 * a. The bottom vnode is not a directory, in which case
483 * just return a new union vnode referencing an
484 * empty top layer and the existing bottom layer.
486 * b. The button vnode is a directory, in which case
487 * create a new directory in the top layer and
488 * and fall through to case 3.
490 * 3. If the top layer succeeded then return a new union
491 * vnode referencing whatever the new top layer and
492 * whatever the bottom layer returned.
496 if ((uerror != 0) && (lerror != 0)) {
502 if (uerror != 0 /* && (lerror == 0) */ ) {
503 if (lowervp->v_type == VDIR) { /* case 2b. */
504 KASSERT(uppervp == NULL, ("uppervp unexpectedly non-NULL"));
506 * oops, uppervp has a problem, we may have to shadow.
508 uerror = union_mkshadow(um, upperdvp, cnp, &uppervp);
517 * Must call union_allocvp with both the upper and lower vnodes
518 * referenced and the upper vnode locked. ap->a_vpp is returned
519 * referenced and locked. lowervp, uppervp, and upperdvp are
520 * absorbed by union_allocvp() whether it succeeds or fails.
522 * upperdvp is the parent directory of uppervp which may be
523 * different, depending on the path, from dvp->un_uppervp. That's
524 * why it is a separate argument. Note that it must be unlocked.
526 * dvp must be locked on entry to the call and will be locked on
530 if (uppervp && uppervp != upperdvp)
531 VOP_UNLOCK(uppervp, NULL, 0, td);
533 VOP_UNLOCK(lowervp, NULL, 0, td);
535 VOP_UNLOCK(upperdvp, NULL, 0, td);
537 error = union_allocvp(ap->a_vpp, dvp->v_mount, dvp, upperdvp, cnp,
538 uppervp, lowervp, 1);
540 UDEBUG(("Create %p = %p %p refs=%d\n", *ap->a_vpp, uppervp, lowervp, (*ap->a_vpp) ? ((*ap->a_vpp)->v_usecount) : -99));
549 * - put away any extra junk laying around. Note that lowervp
550 * (if not NULL) will never be the same as *ap->a_vp and
551 * neither will uppervp, because when we set that state we
552 * NULL-out lowervp or uppervp. On the otherhand, upperdvp
553 * may match uppervp or *ap->a_vpp.
555 * - relock/unlock dvp if appropriate.
560 if (upperdvp == uppervp || upperdvp == *ap->a_vpp)
573 * Restore LOCKPARENT state
577 cnp->cn_flags &= ~CNP_LOCKPARENT;
579 UDEBUG(("Out %d vpp %p/%d lower %p upper %p\n", error, *ap->a_vpp,
580 ((*ap->a_vpp) ? (*ap->a_vpp)->v_usecount : -99),
584 * dvp lock state, determine whether to relock dvp. dvp is expected
585 * to be locked on return if:
587 * - there was an error (except not EJUSTRETURN), or
588 * - we hit the last component and lockparent is true
590 * dvp_is_locked is the current state of the dvp lock, not counting
591 * the possibility that *ap->a_vpp == dvp (in which case it is locked
592 * anyway). Note that *ap->a_vpp == dvp only if no error occured.
595 if (*ap->a_vpp != dvp) {
596 if ((error == 0 || error == EJUSTRETURN) &&
597 (!lockparent || (cnp->cn_flags & CNP_ISLASTCN) == 0)) {
598 VOP_UNLOCK(dvp, NULL, 0, td);
607 if (cnp->cn_namelen == 1 &&
608 cnp->cn_nameptr[0] == '.' &&
610 panic("union_lookup returning . (%p) not same as startdir (%p)", ap->a_vpp, dvp);
620 * a_dvp is locked on entry and remains locked on return. a_vpp is returned
621 * locked if no error occurs, otherwise it is garbage.
623 * union_create(struct vnode *a_dvp, struct vnode **a_vpp,
624 * struct componentname *a_cnp, struct vattr *a_vap)
627 union_create(struct vop_create_args *ap)
629 struct union_node *dun = VTOUNION(ap->a_dvp);
630 struct componentname *cnp = ap->a_cnp;
631 struct thread *td = cnp->cn_td;
635 if ((dvp = union_lock_upper(dun, td)) != NULL) {
639 error = VOP_CREATE(dvp, NCPNULL, &vp, cnp, ap->a_vap);
641 mp = ap->a_dvp->v_mount;
642 VOP_UNLOCK(vp, NULL, 0, td);
643 UDEBUG(("ALLOCVP-1 FROM %p REFS %d\n", vp, vp->v_usecount));
644 error = union_allocvp(ap->a_vpp, mp, NULLVP, NULLVP,
646 UDEBUG(("ALLOCVP-2B FROM %p REFS %d\n", *ap->a_vpp, vp->v_usecount));
648 union_unlock_upper(dvp, td);
654 * union_whiteout(struct vnode *a_dvp, struct componentname *a_cnp,
658 union_whiteout(struct vop_whiteout_args *ap)
660 struct union_node *un = VTOUNION(ap->a_dvp);
661 struct componentname *cnp = ap->a_cnp;
662 struct vnode *uppervp;
663 int error = EOPNOTSUPP;
665 if ((uppervp = union_lock_upper(un, cnp->cn_td)) != NULLVP) {
666 error = VOP_WHITEOUT(un->un_uppervp, NCPNULL, cnp, ap->a_flags);
667 union_unlock_upper(uppervp, cnp->cn_td);
675 * a_dvp is locked on entry and should remain locked on return.
676 * a_vpp is garbagre whether an error occurs or not.
678 * union_mknod(struct vnode *a_dvp, struct vnode **a_vpp,
679 * struct componentname *a_cnp, struct vattr *a_vap)
682 union_mknod(struct vop_mknod_args *ap)
684 struct union_node *dun = VTOUNION(ap->a_dvp);
685 struct componentname *cnp = ap->a_cnp;
689 if ((dvp = union_lock_upper(dun, cnp->cn_td)) != NULL) {
690 error = VOP_MKNOD(dvp, NCPNULL, ap->a_vpp, cnp, ap->a_vap);
691 union_unlock_upper(dvp, cnp->cn_td);
699 * run open VOP. When opening the underlying vnode we have to mimic
700 * vn_open. What we *really* need to do to avoid screwups if the
701 * open semantics change is to call vn_open(). For example, ufs blows
702 * up if you open a file but do not vmio it prior to writing.
704 * union_open(struct vnodeop_desc *a_desc, struct vnode *a_vp, int a_mode,
705 * struct ucred *a_cred, struct thread *a_td)
708 union_open(struct vop_open_args *ap)
710 struct union_node *un = VTOUNION(ap->a_vp);
712 int mode = ap->a_mode;
713 struct ucred *cred = ap->a_cred;
714 struct thread *td = ap->a_td;
719 * If there is an existing upper vp then simply open that.
720 * The upper vp takes precedence over the lower vp. When opening
721 * a lower vp for writing copy it to the uppervp and then open the
724 * At the end of this section tvp will be left locked.
726 if ((tvp = union_lock_upper(un, td)) == NULLVP) {
728 * If the lower vnode is being opened for writing, then
729 * copy the file contents to the upper vnode and open that,
730 * otherwise can simply open the lower vnode.
732 tvp = un->un_lowervp;
733 if ((ap->a_mode & FWRITE) && (tvp->v_type == VREG)) {
734 int docopy = !(mode & O_TRUNC);
735 error = union_copyup(un, docopy, cred, td);
736 tvp = union_lock_upper(un, td);
740 vn_lock(tvp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
746 * We are holding the correct vnode, open it
750 error = VOP_OPEN(tvp, mode, cred, td);
753 * Absolutely necessary or UFS will blowup
755 if (error == 0 && vn_canvmio(tvp) == TRUE) {
756 error = vfs_object_create(tvp, td);
760 * Release any locks held
764 union_unlock_upper(tvp, td);
774 * It is unclear whether a_vp is passed locked or unlocked. Whatever
775 * the case we do not change it.
777 * union_close(struct vnode *a_vp, int a_fflag, struct ucred *a_cred,
778 * struct thread *a_td)
781 union_close(struct vop_close_args *ap)
783 struct union_node *un = VTOUNION(ap->a_vp);
786 if ((vp = un->un_uppervp) == NULLVP) {
787 #ifdef UNION_DIAGNOSTIC
788 if (un->un_openl <= 0)
789 panic("union: un_openl cnt");
795 return (VCALL(vp, VOFFSET(vop_close), ap));
799 * Check access permission on the union vnode.
800 * The access check being enforced is to check
801 * against both the underlying vnode, and any
802 * copied vnode. This ensures that no additional
803 * file permissions are given away simply because
804 * the user caused an implicit file copy.
806 * union_access(struct vnodeop_desc *a_desc, struct vnode *a_vp, int a_mode,
807 * struct ucred *a_cred, struct thread *a_td)
810 union_access(struct vop_access_args *ap)
812 struct union_node *un = VTOUNION(ap->a_vp);
813 struct thread *td = ap->a_td;
818 * Disallow write attempts on filesystems mounted read-only.
820 if ((ap->a_mode & VWRITE) &&
821 (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)) {
822 switch (ap->a_vp->v_type) {
832 if ((vp = union_lock_upper(un, td)) != NULLVP) {
834 error = VCALL(vp, VOFFSET(vop_access), ap);
835 union_unlock_upper(vp, td);
839 if ((vp = un->un_lowervp) != NULLVP) {
840 vn_lock(vp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
844 * Remove VWRITE from a_mode if our mount point is RW, because
845 * we want to allow writes and lowervp may be read-only.
847 if ((un->un_vnode->v_mount->mnt_flag & MNT_RDONLY) == 0)
848 ap->a_mode &= ~VWRITE;
850 error = VCALL(vp, VOFFSET(vop_access), ap);
852 struct union_mount *um;
854 um = MOUNTTOUNIONMOUNT(un->un_vnode->v_mount);
856 if (um->um_op == UNMNT_BELOW) {
857 ap->a_cred = um->um_cred;
858 error = VCALL(vp, VOFFSET(vop_access), ap);
861 VOP_UNLOCK(vp, NULL, 0, td);
867 * We handle getattr only to change the fsid and
870 * It's not clear whether VOP_GETATTR is to be
871 * called with the vnode locked or not. stat() calls
872 * it with (vp) locked, and fstat calls it with
875 * Because of this we cannot use our normal locking functions
876 * if we do not intend to lock the main a_vp node. At the moment
877 * we are running without any specific locking at all, but beware
878 * to any programmer that care must be taken if locking is added
881 * union_getattr(struct vnode *a_vp, struct vattr *a_vap,
882 * struct ucred *a_cred, struct thread *a_td)
885 union_getattr(struct vop_getattr_args *ap)
888 struct union_node *un = VTOUNION(ap->a_vp);
894 * Some programs walk the filesystem hierarchy by counting
895 * links to directories to avoid stat'ing all the time.
896 * This means the link count on directories needs to be "correct".
897 * The only way to do that is to call getattr on both layers
898 * and fix up the link count. The link count will not necessarily
899 * be accurate but will be large enough to defeat the tree walkers.
904 if ((vp = un->un_uppervp) != NULLVP) {
905 error = VOP_GETATTR(vp, vap, ap->a_td);
908 /* XXX isn't this dangerouso without a lock? */
909 union_newsize(ap->a_vp, vap->va_size, VNOVAL);
914 } else if (vp->v_type == VDIR && un->un_lowervp != NULLVP) {
922 error = VOP_GETATTR(vp, vap, ap->a_td);
925 /* XXX isn't this dangerous without a lock? */
926 union_newsize(ap->a_vp, VNOVAL, vap->va_size);
929 if ((vap != ap->a_vap) && (vap->va_type == VDIR))
930 ap->a_vap->va_nlink += vap->va_nlink;
935 * union_setattr(struct vnode *a_vp, struct vattr *a_vap,
936 * struct ucred *a_cred, struct thread *a_td)
939 union_setattr(struct vop_setattr_args *ap)
941 struct union_node *un = VTOUNION(ap->a_vp);
942 struct thread *td = ap->a_td;
943 struct vattr *vap = ap->a_vap;
944 struct vnode *uppervp;
948 * Disallow write attempts on filesystems mounted read-only.
950 if ((ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) &&
951 (vap->va_flags != VNOVAL || vap->va_uid != (uid_t)VNOVAL ||
952 vap->va_gid != (gid_t)VNOVAL || vap->va_atime.tv_sec != VNOVAL ||
953 vap->va_mtime.tv_sec != VNOVAL ||
954 vap->va_mode != (mode_t)VNOVAL)) {
959 * Handle case of truncating lower object to zero size,
960 * by creating a zero length upper object. This is to
961 * handle the case of open with O_TRUNC and O_CREAT.
963 if (un->un_uppervp == NULLVP && (un->un_lowervp->v_type == VREG)) {
964 error = union_copyup(un, (ap->a_vap->va_size != 0),
965 ap->a_cred, ap->a_td);
971 * Try to set attributes in upper layer,
972 * otherwise return read-only filesystem error.
975 if ((uppervp = union_lock_upper(un, td)) != NULLVP) {
976 error = VOP_SETATTR(un->un_uppervp, ap->a_vap,
977 ap->a_cred, ap->a_td);
978 if ((error == 0) && (ap->a_vap->va_size != VNOVAL))
979 union_newsize(ap->a_vp, ap->a_vap->va_size, VNOVAL);
980 union_unlock_upper(uppervp, td);
990 union_getpages(struct vop_getpages_args *ap)
994 r = vnode_pager_generic_getpages(ap->a_vp, ap->a_m,
995 ap->a_count, ap->a_reqpage);
1004 union_putpages(struct vop_putpages_args *ap)
1008 r = vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count,
1009 ap->a_sync, ap->a_rtvals);
1014 * union_read(struct vnode *a_vp, struct uio *a_uio, int a_ioflag,
1015 * struct ucred *a_cred)
1018 union_read(struct vop_read_args *ap)
1020 struct union_node *un = VTOUNION(ap->a_vp);
1021 struct thread *td = ap->a_uio->uio_td;
1025 uvp = union_lock_other(un, td);
1026 KASSERT(uvp != NULL, ("union_read: backing vnode missing!"));
1028 if (ap->a_vp->v_flag & VOBJBUF)
1029 union_vm_coherency(ap->a_vp, ap->a_uio, 0);
1031 error = VOP_READ(uvp, ap->a_uio, ap->a_ioflag, ap->a_cred);
1032 union_unlock_other(uvp, td);
1036 * perhaps the size of the underlying object has changed under
1037 * our feet. take advantage of the offset information present
1038 * in the uio structure.
1041 struct union_node *un = VTOUNION(ap->a_vp);
1042 off_t cur = ap->a_uio->uio_offset;
1044 if (uvp == un->un_uppervp) {
1045 if (cur > un->un_uppersz)
1046 union_newsize(ap->a_vp, cur, VNOVAL);
1048 if (cur > un->un_lowersz)
1049 union_newsize(ap->a_vp, VNOVAL, cur);
1056 * union_write(struct vnode *a_vp, struct uio *a_uio, int a_ioflag,
1057 * struct ucred *a_cred)
1060 union_write(struct vop_read_args *ap)
1062 struct union_node *un = VTOUNION(ap->a_vp);
1063 struct thread *td = ap->a_uio->uio_td;
1064 struct vnode *uppervp;
1067 if ((uppervp = union_lock_upper(un, td)) == NULLVP)
1068 panic("union: missing upper layer in write");
1071 * Since our VM pages are associated with our vnode rather then
1072 * the real vnode, and since we do not run our reads and writes
1073 * through our own VM cache, we have a VM/VFS coherency problem.
1074 * We solve them by invalidating or flushing the associated VM
1075 * pages prior to allowing a normal read or write to occur.
1077 * VM-backed writes (UIO_NOCOPY) have to be converted to normal
1078 * writes because we are not cache-coherent. Normal writes need
1079 * to be made coherent with our VM-backing store, which we do by
1080 * first flushing any dirty VM pages associated with the write
1081 * range, and then destroying any clean VM pages associated with
1085 if (ap->a_uio->uio_segflg == UIO_NOCOPY) {
1086 ap->a_uio->uio_segflg = UIO_SYSSPACE;
1087 } else if (ap->a_vp->v_flag & VOBJBUF) {
1088 union_vm_coherency(ap->a_vp, ap->a_uio, 1);
1091 error = VOP_WRITE(uppervp, ap->a_uio, ap->a_ioflag, ap->a_cred);
1094 * the size of the underlying object may be changed by the
1098 off_t cur = ap->a_uio->uio_offset;
1100 if (cur > un->un_uppersz)
1101 union_newsize(ap->a_vp, cur, VNOVAL);
1103 union_unlock_upper(uppervp, td);
1108 * union_lease(struct vnode *a_vp, struct thread *a_td, struct ucred *a_cred,
1112 union_lease(struct vop_lease_args *ap)
1114 struct vnode *ovp = OTHERVP(ap->a_vp);
1117 return (VCALL(ovp, VOFFSET(vop_lease), ap));
1121 * union_ioctl(struct vnode *a_vp, int a_command, caddr_t a_data, int a_fflag,
1122 * struct ucred *a_cred, struct thread *a_td)
1125 union_ioctl(struct vop_ioctl_args *ap)
1127 struct vnode *ovp = OTHERVP(ap->a_vp);
1130 return (VCALL(ovp, VOFFSET(vop_ioctl), ap));
1134 * union_poll(struct vnode *a_vp, int a_events, struct ucred *a_cred,
1135 * struct thread *a_td)
1138 union_poll(struct vop_poll_args *ap)
1140 struct vnode *ovp = OTHERVP(ap->a_vp);
1143 return (VCALL(ovp, VOFFSET(vop_poll), ap));
1147 * union_revoke(struct vnode *a_vp, int a_flags, struct thread *a_td)
1150 union_revoke(struct vop_revoke_args *ap)
1152 struct vnode *vp = ap->a_vp;
1155 VOP_REVOKE(UPPERVP(vp), ap->a_flags);
1157 VOP_REVOKE(LOWERVP(vp), ap->a_flags);
1163 * union_mmap(struct vnode *a_vp, int a_fflags, struct ucred *a_cred,
1164 * struct thread *a_td)
1167 union_mmap(struct vop_mmap_args *ap)
1169 struct vnode *ovp = OTHERVP(ap->a_vp);
1172 return (VCALL(ovp, VOFFSET(vop_mmap), ap));
1176 * union_fsync(struct vnode *a_vp, struct ucred *a_cred, int a_waitfor,
1177 * struct thread *a_td)
1180 union_fsync(struct vop_fsync_args *ap)
1183 struct thread *td = ap->a_td;
1184 struct vnode *targetvp;
1185 struct union_node *un = VTOUNION(ap->a_vp);
1187 if ((targetvp = union_lock_other(un, td)) != NULLVP) {
1188 error = VOP_FSYNC(targetvp, ap->a_waitfor, td);
1189 union_unlock_other(targetvp, td);
1198 * Remove the specified cnp. The dvp and vp are passed to us locked
1199 * and must remain locked on return.
1201 * union_remove(struct vnode *a_dvp, struct vnode *a_vp,
1202 * struct componentname *a_cnp)
1205 union_remove(struct vop_remove_args *ap)
1207 struct union_node *dun = VTOUNION(ap->a_dvp);
1208 struct union_node *un = VTOUNION(ap->a_vp);
1209 struct componentname *cnp = ap->a_cnp;
1210 struct thread *td = cnp->cn_td;
1211 struct vnode *uppervp;
1212 struct vnode *upperdvp;
1215 if ((upperdvp = union_lock_upper(dun, td)) == NULLVP)
1216 panic("union remove: null upper vnode");
1218 if ((uppervp = union_lock_upper(un, td)) != NULLVP) {
1219 if (union_dowhiteout(un, cnp->cn_cred, td))
1220 cnp->cn_flags |= CNP_DOWHITEOUT;
1221 error = VOP_REMOVE(upperdvp, NCPNULL, uppervp, cnp);
1225 union_removed_upper(un);
1227 union_unlock_upper(uppervp, td);
1229 error = union_mkwhiteout(
1230 MOUNTTOUNIONMOUNT(ap->a_dvp->v_mount),
1231 upperdvp, ap->a_cnp, un->un_path);
1233 union_unlock_upper(upperdvp, td);
1240 * tdvp will be locked on entry, vp will not be locked on entry.
1241 * tdvp should remain locked on return and vp should remain unlocked
1244 * union_link(struct vnode *a_tdvp, struct vnode *a_vp,
1245 * struct componentname *a_cnp)
1248 union_link(struct vop_link_args *ap)
1250 struct componentname *cnp = ap->a_cnp;
1251 struct thread *td = cnp->cn_td;
1252 struct union_node *dun = VTOUNION(ap->a_tdvp);
1257 if (ap->a_tdvp->v_op != ap->a_vp->v_op) {
1260 struct union_node *tun = VTOUNION(ap->a_vp);
1262 if (tun->un_uppervp == NULLVP) {
1263 vn_lock(ap->a_vp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
1265 if (dun->un_uppervp == tun->un_dirvp) {
1266 if (dun->un_flags & UN_ULOCK) {
1267 dun->un_flags &= ~UN_ULOCK;
1268 VOP_UNLOCK(dun->un_uppervp, NULL, 0, td);
1272 error = union_copyup(tun, 1, cnp->cn_cred, td);
1274 if (dun->un_uppervp == tun->un_dirvp) {
1275 vn_lock(dun->un_uppervp, NULL,
1276 LK_EXCLUSIVE | LK_RETRY, td);
1277 dun->un_flags |= UN_ULOCK;
1280 VOP_UNLOCK(ap->a_vp, NULL, 0, td);
1282 vp = tun->un_uppervp;
1289 * Make sure upper is locked, then unlock the union directory we were
1290 * called with to avoid a deadlock while we are calling VOP_LINK on
1291 * the upper (with tdvp locked and vp not locked). Our ap->a_tdvp
1292 * is expected to be locked on return.
1295 if ((tdvp = union_lock_upper(dun, td)) == NULLVP)
1298 VOP_UNLOCK(ap->a_tdvp, NULL, 0, td); /* unlock calling node */
1299 error = VOP_LINK(tdvp, NCPNULL, vp, cnp); /* call link on upper */
1302 * We have to unlock tdvp prior to relocking our calling node in
1303 * order to avoid a deadlock.
1305 union_unlock_upper(tdvp, td);
1306 vn_lock(ap->a_tdvp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
1311 * union_rename(struct vnode *a_fdvp, struct vnode *a_fvp,
1312 * struct componentname *a_fcnp, struct vnode *a_tdvp,
1313 * struct vnode *a_tvp, struct componentname *a_tcnp)
1316 union_rename(struct vop_rename_args *ap)
1319 struct vnode *fdvp = ap->a_fdvp;
1320 struct vnode *fvp = ap->a_fvp;
1321 struct vnode *tdvp = ap->a_tdvp;
1322 struct vnode *tvp = ap->a_tvp;
1325 * Figure out what fdvp to pass to our upper or lower vnode. If we
1326 * replace the fdvp, release the original one and ref the new one.
1329 if (fdvp->v_op == union_vnodeop_p) { /* always true */
1330 struct union_node *un = VTOUNION(fdvp);
1331 if (un->un_uppervp == NULLVP) {
1333 * this should never happen in normal
1334 * operation but might if there was
1335 * a problem creating the top-level shadow
1341 fdvp = un->un_uppervp;
1347 * Figure out what fvp to pass to our upper or lower vnode. If we
1348 * replace the fvp, release the original one and ref the new one.
1351 if (fvp->v_op == union_vnodeop_p) { /* always true */
1352 struct union_node *un = VTOUNION(fvp);
1354 struct union_mount *um = MOUNTTOUNIONMOUNT(fvp->v_mount);
1357 if (un->un_uppervp == NULLVP) {
1358 switch(fvp->v_type) {
1360 vn_lock(un->un_vnode, NULL, LK_EXCLUSIVE | LK_RETRY, ap->a_fcnp->cn_td);
1361 error = union_copyup(un, 1, ap->a_fcnp->cn_cred, ap->a_fcnp->cn_td);
1362 VOP_UNLOCK(un->un_vnode, NULL, 0, ap->a_fcnp->cn_td);
1370 * There is only one way to rename a directory
1371 * based in the lowervp, and that is to copy
1372 * the entire directory hierarchy. Otherwise
1373 * it would not last across a reboot.
1378 vn_lock(fdvp, NULL, LK_EXCLUSIVE | LK_RETRY, ap->a_fcnp->cn_td);
1379 error = union_mkshadow(um, fdvp,
1380 ap->a_fcnp, &un->un_uppervp);
1381 VOP_UNLOCK(fdvp, NULL, 0, ap->a_fcnp->cn_td);
1383 VOP_UNLOCK(un->un_uppervp, NULL, 0, ap->a_fcnp->cn_td);
1394 if (un->un_lowervp != NULLVP)
1395 ap->a_fcnp->cn_flags |= CNP_DOWHITEOUT;
1396 fvp = un->un_uppervp;
1402 * Figure out what tdvp (destination directory) to pass to the
1403 * lower level. If we replace it with uppervp, we need to vput the
1404 * old one. The exclusive lock is transfered to what we will pass
1405 * down in the VOP_RENAME and we replace uppervp with a simple
1409 if (tdvp->v_op == union_vnodeop_p) {
1410 struct union_node *un = VTOUNION(tdvp);
1412 if (un->un_uppervp == NULLVP) {
1414 * this should never happen in normal
1415 * operation but might if there was
1416 * a problem creating the top-level shadow
1424 * new tdvp is a lock and reference on uppervp, put away
1427 tdvp = union_lock_upper(un, ap->a_tcnp->cn_td);
1432 * Figure out what tvp (destination file) to pass to the
1435 * If the uppervp file does not exist put away the (wrong)
1436 * file and change tvp to NULL.
1439 if (tvp != NULLVP && tvp->v_op == union_vnodeop_p) {
1440 struct union_node *un = VTOUNION(tvp);
1442 tvp = union_lock_upper(un, ap->a_tcnp->cn_td);
1444 /* note: tvp may be NULL */
1448 * VOP_RENAME releases/vputs prior to returning, so we have no
1452 return (VOP_RENAME(fdvp, NCPNULL, fvp, ap->a_fcnp, tdvp, NCPNULL, tvp, ap->a_tcnp));
1455 * Error. We still have to release / vput the various elements.
1463 if (tvp != NULLVP) {
1473 * union_mkdir(struct vnode *a_dvp, struct vnode **a_vpp,
1474 * struct componentname *a_cnp, struct vattr *a_vap)
1477 union_mkdir(struct vop_mkdir_args *ap)
1479 struct union_node *dun = VTOUNION(ap->a_dvp);
1480 struct componentname *cnp = ap->a_cnp;
1481 struct thread *td = cnp->cn_td;
1482 struct vnode *upperdvp;
1485 if ((upperdvp = union_lock_upper(dun, td)) != NULLVP) {
1488 error = VOP_MKDIR(upperdvp, NCPNULL, &vp, cnp, ap->a_vap);
1489 union_unlock_upper(upperdvp, td);
1492 VOP_UNLOCK(vp, NULL, 0, td);
1493 UDEBUG(("ALLOCVP-2 FROM %p REFS %d\n", vp, vp->v_usecount));
1494 error = union_allocvp(ap->a_vpp, ap->a_dvp->v_mount,
1495 ap->a_dvp, NULLVP, cnp, vp, NULLVP, 1);
1496 UDEBUG(("ALLOCVP-2B FROM %p REFS %d\n", *ap->a_vpp, vp->v_usecount));
1503 * union_rmdir(struct vnode *a_dvp, struct vnode *a_vp,
1504 * struct componentname *a_cnp)
1507 union_rmdir(struct vop_rmdir_args *ap)
1509 struct union_node *dun = VTOUNION(ap->a_dvp);
1510 struct union_node *un = VTOUNION(ap->a_vp);
1511 struct componentname *cnp = ap->a_cnp;
1512 struct thread *td = cnp->cn_td;
1513 struct vnode *upperdvp;
1514 struct vnode *uppervp;
1517 if ((upperdvp = union_lock_upper(dun, td)) == NULLVP)
1518 panic("union rmdir: null upper vnode");
1520 if ((uppervp = union_lock_upper(un, td)) != NULLVP) {
1521 if (union_dowhiteout(un, cnp->cn_cred, td))
1522 cnp->cn_flags |= CNP_DOWHITEOUT;
1523 error = VOP_RMDIR(upperdvp, NCPNULL, uppervp, ap->a_cnp);
1524 union_unlock_upper(uppervp, td);
1526 error = union_mkwhiteout(
1527 MOUNTTOUNIONMOUNT(ap->a_dvp->v_mount),
1528 dun->un_uppervp, ap->a_cnp, un->un_path);
1530 union_unlock_upper(upperdvp, td);
1537 * dvp is locked on entry and remains locked on return. a_vpp is garbage
1540 * union_symlink(struct vnode *a_dvp, struct vnode **a_vpp,
1541 * struct componentname *a_cnp, struct vattr *a_vap,
1545 union_symlink(struct vop_symlink_args *ap)
1547 struct union_node *dun = VTOUNION(ap->a_dvp);
1548 struct componentname *cnp = ap->a_cnp;
1549 struct thread *td = cnp->cn_td;
1553 if ((dvp = union_lock_upper(dun, td)) != NULLVP) {
1554 error = VOP_SYMLINK(dvp, NCPNULL, ap->a_vpp, cnp, ap->a_vap,
1556 union_unlock_upper(dvp, td);
1562 * union_readdir works in concert with getdirentries and
1563 * readdir(3) to provide a list of entries in the unioned
1564 * directories. getdirentries is responsible for walking
1565 * down the union stack. readdir(3) is responsible for
1566 * eliminating duplicate names from the returned data stream.
1568 * union_readdir(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred,
1569 * int *a_eofflag, u_long *a_cookies, int a_ncookies)
1572 union_readdir(struct vop_readdir_args *ap)
1574 struct union_node *un = VTOUNION(ap->a_vp);
1575 struct thread *td = ap->a_uio->uio_td;
1579 if ((uvp = union_lock_upper(un, td)) != NULLVP) {
1581 error = VCALL(uvp, VOFFSET(vop_readdir), ap);
1582 union_unlock_upper(uvp, td);
1588 * union_readlink(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred)
1591 union_readlink(struct vop_readlink_args *ap)
1594 struct union_node *un = VTOUNION(ap->a_vp);
1595 struct uio *uio = ap->a_uio;
1596 struct thread *td = uio->uio_td;
1599 vp = union_lock_other(un, td);
1600 KASSERT(vp != NULL, ("union_readlink: backing vnode missing!"));
1603 error = VCALL(vp, VOFFSET(vop_readlink), ap);
1604 union_unlock_other(vp, td);
1612 * Called with the vnode locked. We are expected to unlock the vnode.
1614 * union_inactive(struct vnode *a_vp, struct thread *a_td)
1617 union_inactive(struct vop_inactive_args *ap)
1619 struct vnode *vp = ap->a_vp;
1620 struct thread *td = ap->a_td;
1621 struct union_node *un = VTOUNION(vp);
1625 * Do nothing (and _don't_ bypass).
1626 * Wait to vrele lowervp until reclaim,
1627 * so that until then our union_node is in the
1628 * cache and reusable.
1630 * NEEDSWORK: Someday, consider inactive'ing
1631 * the lowervp and then trying to reactivate it
1632 * with capabilities (v_id)
1633 * like they do in the name lookup cache code.
1634 * That's too much work for now.
1637 if (un->un_dircache != 0) {
1638 for (vpp = un->un_dircache; *vpp != NULLVP; vpp++)
1640 free (un->un_dircache, M_TEMP);
1641 un->un_dircache = 0;
1645 if ((un->un_flags & UN_ULOCK) && un->un_uppervp) {
1646 un->un_flags &= ~UN_ULOCK;
1647 VOP_UNLOCK(un->un_uppervp, NULL, 0, td);
1651 VOP_UNLOCK(vp, NULL, 0, td);
1653 if ((un->un_flags & UN_CACHED) == 0)
1660 * union_reclaim(struct vnode *a_vp)
1663 union_reclaim(struct vop_reclaim_args *ap)
1665 union_freevp(ap->a_vp);
1671 union_lock(struct vop_lock_args *ap)
1674 struct vnode *vp = ap->a_vp;
1675 struct thread *td = ap->a_td;
1676 int flags = ap->a_flags;
1677 struct union_node *un;
1681 error = vop_stdlock(ap);
1687 * Lock the upper if it exists and this is an exclusive lock
1690 if (un->un_uppervp != NULLVP &&
1691 (flags & LK_TYPE_MASK) == LK_EXCLUSIVE) {
1692 if ((un->un_flags & UN_ULOCK) == 0 && vp->v_usecount) {
1693 error = vn_lock(un->un_uppervp, ap->a_vlock,
1696 struct vop_unlock_args uap = { 0 };
1697 uap.a_vp = ap->a_vp;
1698 uap.a_vlock = ap->a_vlock;
1699 uap.a_flags = ap->a_flags;
1700 uap.a_td = ap->a_td;
1701 vop_stdunlock(&uap);
1704 un->un_flags |= UN_ULOCK;
1715 * Unlock our union node. This also unlocks uppervp.
1717 * union_unlock(struct vnode *a_vp, lwkt_tokref_t a_vlock, int a_flags,
1718 * struct thread *a_td)
1721 union_unlock(struct vop_unlock_args *ap)
1725 struct union_node *un = VTOUNION(ap->a_vp);
1727 KASSERT((un->un_uppervp == NULL || un->un_uppervp->v_usecount > 0), ("uppervp usecount is 0"));
1730 error = vop_stdunlock(ap);
1734 * If no exclusive locks remain and we are holding an uppervp lock,
1735 * remove the uppervp lock.
1738 if ((un->un_flags & UN_ULOCK) &&
1739 lockstatus(&un->un_lock, NULL) != LK_EXCLUSIVE) {
1740 un->un_flags &= ~UN_ULOCK;
1741 VOP_UNLOCK(un->un_uppervp, NULL, LK_EXCLUSIVE, td);
1750 * There isn't much we can do. We cannot push through to the real vnode
1751 * to get to the underlying device because this will bypass data
1752 * cached by the real vnode.
1754 * For some reason we cannot return the 'real' vnode either, it seems
1755 * to blow up memory maps.
1757 * union_bmap(struct vnode *a_vp, daddr_t a_bn, struct vnode **a_vpp,
1758 * daddr_t *a_bnp, int *a_runp, int *a_runb)
1761 union_bmap(struct vop_bmap_args *ap)
1767 * union_print(struct vnode *a_vp)
1770 union_print(struct vop_print_args *ap)
1772 struct vnode *vp = ap->a_vp;
1774 printf("\ttag VT_UNION, vp=%p, uppervp=%p, lowervp=%p\n",
1775 vp, UPPERVP(vp), LOWERVP(vp));
1776 if (UPPERVP(vp) != NULLVP)
1777 vprint("union: upper", UPPERVP(vp));
1778 if (LOWERVP(vp) != NULLVP)
1779 vprint("union: lower", LOWERVP(vp));
1785 * union_pathconf(struct vnode *a_vp, int a_name, int *a_retval)
1788 union_pathconf(struct vop_pathconf_args *ap)
1791 struct thread *td = curthread; /* XXX */
1792 struct union_node *un = VTOUNION(ap->a_vp);
1795 vp = union_lock_other(un, td);
1796 KASSERT(vp != NULL, ("union_pathconf: backing vnode missing!"));
1799 error = VCALL(vp, VOFFSET(vop_pathconf), ap);
1800 union_unlock_other(vp, td);
1806 * union_advlock(struct vnode *a_vp, caddr_t a_id, int a_op,
1807 * struct flock *a_fl, int a_flags)
1810 union_advlock(struct vop_advlock_args *ap)
1812 struct vnode *ovp = OTHERVP(ap->a_vp);
1815 return (VCALL(ovp, VOFFSET(vop_advlock), ap));
1820 * XXX - vop_strategy must be hand coded because it has no
1821 * YYY - and it is not coherent with anything
1823 * vnode in its arguments.
1824 * This goes away with a merged VM/buffer cache.
1826 * union_strategy(struct vnode *a_vp, struct buf *a_bp)
1829 union_strategy(struct vop_strategy_args *ap)
1831 struct buf *bp = ap->a_bp;
1832 struct vnode *othervp = OTHERVP(bp->b_vp);
1835 if (othervp == NULLVP)
1836 panic("union_strategy: nil vp");
1837 if (((bp->b_flags & B_READ) == 0) &&
1838 (othervp == LOWERVP(bp->b_vp)))
1839 panic("union_strategy: writing to lowervp");
1841 return (VOP_STRATEGY(othervp, bp));
1845 * Global vfs data structures
1847 vop_t **union_vnodeop_p;
1848 static struct vnodeopv_entry_desc union_vnodeop_entries[] = {
1849 { &vop_default_desc, (vop_t *) vop_defaultop },
1850 { &vop_access_desc, (vop_t *) union_access },
1851 { &vop_advlock_desc, (vop_t *) union_advlock },
1852 { &vop_bmap_desc, (vop_t *) union_bmap },
1853 { &vop_close_desc, (vop_t *) union_close },
1854 { &vop_create_desc, (vop_t *) union_create },
1855 { &vop_fsync_desc, (vop_t *) union_fsync },
1856 { &vop_getpages_desc, (vop_t *) union_getpages },
1857 { &vop_putpages_desc, (vop_t *) union_putpages },
1858 { &vop_getattr_desc, (vop_t *) union_getattr },
1859 { &vop_inactive_desc, (vop_t *) union_inactive },
1860 { &vop_ioctl_desc, (vop_t *) union_ioctl },
1861 { &vop_islocked_desc, (vop_t *) vop_stdislocked },
1862 { &vop_lease_desc, (vop_t *) union_lease },
1863 { &vop_link_desc, (vop_t *) union_link },
1864 { &vop_lock_desc, (vop_t *) union_lock },
1865 { &vop_lookup_desc, (vop_t *) union_lookup },
1866 { &vop_mkdir_desc, (vop_t *) union_mkdir },
1867 { &vop_mknod_desc, (vop_t *) union_mknod },
1868 { &vop_mmap_desc, (vop_t *) union_mmap },
1869 { &vop_open_desc, (vop_t *) union_open },
1870 { &vop_pathconf_desc, (vop_t *) union_pathconf },
1871 { &vop_poll_desc, (vop_t *) union_poll },
1872 { &vop_print_desc, (vop_t *) union_print },
1873 { &vop_read_desc, (vop_t *) union_read },
1874 { &vop_readdir_desc, (vop_t *) union_readdir },
1875 { &vop_readlink_desc, (vop_t *) union_readlink },
1876 { &vop_reclaim_desc, (vop_t *) union_reclaim },
1877 { &vop_remove_desc, (vop_t *) union_remove },
1878 { &vop_rename_desc, (vop_t *) union_rename },
1879 { &vop_revoke_desc, (vop_t *) union_revoke },
1880 { &vop_rmdir_desc, (vop_t *) union_rmdir },
1881 { &vop_setattr_desc, (vop_t *) union_setattr },
1882 { &vop_strategy_desc, (vop_t *) union_strategy },
1883 { &vop_symlink_desc, (vop_t *) union_symlink },
1884 { &vop_unlock_desc, (vop_t *) union_unlock },
1885 { &vop_whiteout_desc, (vop_t *) union_whiteout },
1886 { &vop_write_desc, (vop_t *) union_write },
1889 static struct vnodeopv_desc union_vnodeop_opv_desc =
1890 { &union_vnodeop_p, union_vnodeop_entries };
1892 VNODEOP_SET(union_vnodeop_opv_desc);