1 /*-
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed
6 * to Berkeley by John Heidemann of the UCLA Ficus project.
7 *
8 * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD: releng/8.1/sys/kern/vfs_default.c 206414 2010-04-09 08:45:30Z kib $");
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/bio.h>
41 #include <sys/buf.h>
42 #include <sys/conf.h>
43 #include <sys/event.h>
44 #include <sys/kernel.h>
45 #include <sys/limits.h>
46 #include <sys/lock.h>
47 #include <sys/lockf.h>
48 #include <sys/malloc.h>
49 #include <sys/mount.h>
50 #include <sys/mutex.h>
51 #include <sys/namei.h>
52 #include <sys/fcntl.h>
53 #include <sys/unistd.h>
54 #include <sys/vnode.h>
55 #include <sys/dirent.h>
56 #include <sys/poll.h>
57
58 #include <security/mac/mac_framework.h>
59
60 #include <vm/vm.h>
61 #include <vm/vm_object.h>
62 #include <vm/vm_extern.h>
63 #include <vm/pmap.h>
64 #include <vm/vm_map.h>
65 #include <vm/vm_page.h>
66 #include <vm/vm_pager.h>
67 #include <vm/vnode_pager.h>
68
69 static int vop_nolookup(struct vop_lookup_args *);
70 static int vop_norename(struct vop_rename_args *);
71 static int vop_nostrategy(struct vop_strategy_args *);
72 static int get_next_dirent(struct vnode *vp, struct dirent **dpp,
73 char *dirbuf, int dirbuflen, off_t *off,
74 char **cpos, int *len, int *eofflag,
75 struct thread *td);
76 static int dirent_exists(struct vnode *vp, const char *dirname,
77 struct thread *td);
78
79 #define DIRENT_MINSIZE (sizeof(struct dirent) - (MAXNAMLEN+1) + 4)
80
81 /*
82 * This vnode table stores what we want to do if the filesystem doesn't
83 * implement a particular VOP.
84 *
85 * If there is no specific entry here, we will return EOPNOTSUPP.
86 *
87 * Note that every filesystem has to implement either vop_access
88 * or vop_accessx; failing to do so will result in immediate crash
89 * due to stack overflow, as vop_stdaccess() calls vop_stdaccessx(),
90 * which calls vop_stdaccess() etc.
91 */
92
93 struct vop_vector default_vnodeops = {
94 .vop_default = NULL,
95 .vop_bypass = VOP_EOPNOTSUPP,
96
97 .vop_access = vop_stdaccess,
98 .vop_accessx = vop_stdaccessx,
99 .vop_advlock = vop_stdadvlock,
100 .vop_advlockasync = vop_stdadvlockasync,
101 .vop_bmap = vop_stdbmap,
102 .vop_close = VOP_NULL,
103 .vop_fsync = VOP_NULL,
104 .vop_getpages = vop_stdgetpages,
105 .vop_getwritemount = vop_stdgetwritemount,
106 .vop_inactive = VOP_NULL,
107 .vop_ioctl = VOP_ENOTTY,
108 .vop_kqfilter = vop_stdkqfilter,
109 .vop_islocked = vop_stdislocked,
110 .vop_lock1 = vop_stdlock,
111 .vop_lookup = vop_nolookup,
112 .vop_open = VOP_NULL,
113 .vop_pathconf = VOP_EINVAL,
114 .vop_poll = vop_nopoll,
115 .vop_putpages = vop_stdputpages,
116 .vop_readlink = VOP_EINVAL,
117 .vop_rename = vop_norename,
118 .vop_revoke = VOP_PANIC,
119 .vop_strategy = vop_nostrategy,
120 .vop_unlock = vop_stdunlock,
121 .vop_vptocnp = vop_stdvptocnp,
122 .vop_vptofh = vop_stdvptofh,
123 };
124
125 /*
126 * Series of placeholder functions for various error returns for
127 * VOPs.
128 */
129
130 int
131 vop_eopnotsupp(struct vop_generic_args *ap)
132 {
133 /*
134 printf("vop_notsupp[%s]\n", ap->a_desc->vdesc_name);
135 */
136
137 return (EOPNOTSUPP);
138 }
139
140 int
141 vop_ebadf(struct vop_generic_args *ap)
142 {
143
144 return (EBADF);
145 }
146
147 int
148 vop_enotty(struct vop_generic_args *ap)
149 {
150
151 return (ENOTTY);
152 }
153
154 int
155 vop_einval(struct vop_generic_args *ap)
156 {
157
158 return (EINVAL);
159 }
160
161 int
162 vop_enoent(struct vop_generic_args *ap)
163 {
164
165 return (ENOENT);
166 }
167
168 int
169 vop_null(struct vop_generic_args *ap)
170 {
171
172 return (0);
173 }
174
175 /*
176 * Helper function to panic on some bad VOPs in some filesystems.
177 */
178 int
179 vop_panic(struct vop_generic_args *ap)
180 {
181
182 panic("filesystem goof: vop_panic[%s]", ap->a_desc->vdesc_name);
183 }
184
185 /*
186 * vop_std<something> and vop_no<something> are default functions for use by
187 * filesystems that need the "default reasonable" implementation for a
188 * particular operation.
189 *
190 * The documentation for the operations they implement exists (if it exists)
191 * in the VOP_<SOMETHING>(9) manpage (all uppercase).
192 */
193
194 /*
195 * Default vop for filesystems that do not support name lookup
196 */
197 static int
198 vop_nolookup(ap)
199 struct vop_lookup_args /* {
200 struct vnode *a_dvp;
201 struct vnode **a_vpp;
202 struct componentname *a_cnp;
203 } */ *ap;
204 {
205
206 *ap->a_vpp = NULL;
207 return (ENOTDIR);
208 }
209
210 /*
211 * vop_norename:
212 *
213 * Handle unlock and reference counting for arguments of vop_rename
214 * for filesystems that do not implement rename operation.
215 */
216 static int
217 vop_norename(struct vop_rename_args *ap)
218 {
219
220 vop_rename_fail(ap);
221 return (EOPNOTSUPP);
222 }
223
224 /*
225 * vop_nostrategy:
226 *
227 * Strategy routine for VFS devices that have none.
228 *
229 * BIO_ERROR and B_INVAL must be cleared prior to calling any strategy
230 * routine. Typically this is done for a BIO_READ strategy call.
231 * Typically B_INVAL is assumed to already be clear prior to a write
232 * and should not be cleared manually unless you just made the buffer
233 * invalid. BIO_ERROR should be cleared either way.
234 */
235
236 static int
237 vop_nostrategy (struct vop_strategy_args *ap)
238 {
239 printf("No strategy for buffer at %p\n", ap->a_bp);
240 vprint("vnode", ap->a_vp);
241 ap->a_bp->b_ioflags |= BIO_ERROR;
242 ap->a_bp->b_error = EOPNOTSUPP;
243 bufdone(ap->a_bp);
244 return (EOPNOTSUPP);
245 }
246
247 static int
248 get_next_dirent(struct vnode *vp, struct dirent **dpp, char *dirbuf,
249 int dirbuflen, off_t *off, char **cpos, int *len,
250 int *eofflag, struct thread *td)
251 {
252 int error, reclen;
253 struct uio uio;
254 struct iovec iov;
255 struct dirent *dp;
256
257 KASSERT(VOP_ISLOCKED(vp), ("vp %p is not locked", vp));
258 KASSERT(vp->v_type == VDIR, ("vp %p is not a directory", vp));
259
260 if (*len == 0) {
261 iov.iov_base = dirbuf;
262 iov.iov_len = dirbuflen;
263
264 uio.uio_iov = &iov;
265 uio.uio_iovcnt = 1;
266 uio.uio_offset = *off;
267 uio.uio_resid = dirbuflen;
268 uio.uio_segflg = UIO_SYSSPACE;
269 uio.uio_rw = UIO_READ;
270 uio.uio_td = td;
271
272 *eofflag = 0;
273
274 #ifdef MAC
275 error = mac_vnode_check_readdir(td->td_ucred, vp);
276 if (error == 0)
277 #endif
278 error = VOP_READDIR(vp, &uio, td->td_ucred, eofflag,
279 NULL, NULL);
280 if (error)
281 return (error);
282
283 *off = uio.uio_offset;
284
285 *cpos = dirbuf;
286 *len = (dirbuflen - uio.uio_resid);
287 }
288
289 dp = (struct dirent *)(*cpos);
290 reclen = dp->d_reclen;
291 *dpp = dp;
292
293 /* check for malformed directory.. */
294 if (reclen < DIRENT_MINSIZE)
295 return (EINVAL);
296
297 *cpos += reclen;
298 *len -= reclen;
299
300 return (0);
301 }
302
303 /*
304 * Check if a named file exists in a given directory vnode.
305 */
306 static int
307 dirent_exists(struct vnode *vp, const char *dirname, struct thread *td)
308 {
309 char *dirbuf, *cpos;
310 int error, eofflag, dirbuflen, len, found;
311 off_t off;
312 struct dirent *dp;
313 struct vattr va;
314
315 KASSERT(VOP_ISLOCKED(vp), ("vp %p is not locked", vp));
316 KASSERT(vp->v_type == VDIR, ("vp %p is not a directory", vp));
317
318 found = 0;
319
320 error = VOP_GETATTR(vp, &va, td->td_ucred);
321 if (error)
322 return (found);
323
324 dirbuflen = DEV_BSIZE;
325 if (dirbuflen < va.va_blocksize)
326 dirbuflen = va.va_blocksize;
327 dirbuf = (char *)malloc(dirbuflen, M_TEMP, M_WAITOK);
328
329 off = 0;
330 len = 0;
331 do {
332 error = get_next_dirent(vp, &dp, dirbuf, dirbuflen, &off,
333 &cpos, &len, &eofflag, td);
334 if (error)
335 goto out;
336
337 if ((dp->d_type != DT_WHT) &&
338 !strcmp(dp->d_name, dirname)) {
339 found = 1;
340 goto out;
341 }
342 } while (len > 0 || !eofflag);
343
344 out:
345 free(dirbuf, M_TEMP);
346 return (found);
347 }
348
349 int
350 vop_stdaccess(struct vop_access_args *ap)
351 {
352
353 KASSERT((ap->a_accmode & ~(VEXEC | VWRITE | VREAD | VADMIN |
354 VAPPEND)) == 0, ("invalid bit in accmode"));
355
356 return (VOP_ACCESSX(ap->a_vp, ap->a_accmode, ap->a_cred, ap->a_td));
357 }
358
359 int
360 vop_stdaccessx(struct vop_accessx_args *ap)
361 {
362 int error;
363 accmode_t accmode = ap->a_accmode;
364
365 error = vfs_unixify_accmode(&accmode);
366 if (error != 0)
367 return (error);
368
369 if (accmode == 0)
370 return (0);
371
372 return (VOP_ACCESS(ap->a_vp, accmode, ap->a_cred, ap->a_td));
373 }
374
375 /*
376 * Advisory record locking support
377 */
378 int
379 vop_stdadvlock(struct vop_advlock_args *ap)
380 {
381 struct vnode *vp;
382 struct ucred *cred;
383 struct vattr vattr;
384 int error;
385
386 vp = ap->a_vp;
387 cred = curthread->td_ucred;
388 vn_lock(vp, LK_SHARED | LK_RETRY);
389 error = VOP_GETATTR(vp, &vattr, cred);
390 VOP_UNLOCK(vp, 0);
391 if (error)
392 return (error);
393
394 return (lf_advlock(ap, &(vp->v_lockf), vattr.va_size));
395 }
396
397 int
398 vop_stdadvlockasync(struct vop_advlockasync_args *ap)
399 {
400 struct vnode *vp;
401 struct ucred *cred;
402 struct vattr vattr;
403 int error;
404
405 vp = ap->a_vp;
406 cred = curthread->td_ucred;
407 vn_lock(vp, LK_SHARED | LK_RETRY);
408 error = VOP_GETATTR(vp, &vattr, cred);
409 VOP_UNLOCK(vp, 0);
410 if (error)
411 return (error);
412
413 return (lf_advlockasync(ap, &(vp->v_lockf), vattr.va_size));
414 }
415
416 /*
417 * vop_stdpathconf:
418 *
419 * Standard implementation of POSIX pathconf, to get information about limits
420 * for a filesystem.
421 * Override per filesystem for the case where the filesystem has smaller
422 * limits.
423 */
424 int
425 vop_stdpathconf(ap)
426 struct vop_pathconf_args /* {
427 struct vnode *a_vp;
428 int a_name;
429 int *a_retval;
430 } */ *ap;
431 {
432
433 switch (ap->a_name) {
434 case _PC_NAME_MAX:
435 *ap->a_retval = NAME_MAX;
436 return (0);
437 case _PC_PATH_MAX:
438 *ap->a_retval = PATH_MAX;
439 return (0);
440 case _PC_LINK_MAX:
441 *ap->a_retval = LINK_MAX;
442 return (0);
443 case _PC_MAX_CANON:
444 *ap->a_retval = MAX_CANON;
445 return (0);
446 case _PC_MAX_INPUT:
447 *ap->a_retval = MAX_INPUT;
448 return (0);
449 case _PC_PIPE_BUF:
450 *ap->a_retval = PIPE_BUF;
451 return (0);
452 case _PC_CHOWN_RESTRICTED:
453 *ap->a_retval = 1;
454 return (0);
455 case _PC_VDISABLE:
456 *ap->a_retval = _POSIX_VDISABLE;
457 return (0);
458 default:
459 return (EINVAL);
460 }
461 /* NOTREACHED */
462 }
463
464 /*
465 * Standard lock, unlock and islocked functions.
466 */
467 int
468 vop_stdlock(ap)
469 struct vop_lock1_args /* {
470 struct vnode *a_vp;
471 int a_flags;
472 char *file;
473 int line;
474 } */ *ap;
475 {
476 struct vnode *vp = ap->a_vp;
477
478 return (_lockmgr_args(vp->v_vnlock, ap->a_flags, VI_MTX(vp),
479 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, ap->a_file,
480 ap->a_line));
481 }
482
483 /* See above. */
484 int
485 vop_stdunlock(ap)
486 struct vop_unlock_args /* {
487 struct vnode *a_vp;
488 int a_flags;
489 } */ *ap;
490 {
491 struct vnode *vp = ap->a_vp;
492
493 return (lockmgr(vp->v_vnlock, ap->a_flags | LK_RELEASE, VI_MTX(vp)));
494 }
495
496 /* See above. */
497 int
498 vop_stdislocked(ap)
499 struct vop_islocked_args /* {
500 struct vnode *a_vp;
501 } */ *ap;
502 {
503
504 return (lockstatus(ap->a_vp->v_vnlock));
505 }
506
507 /*
508 * Return true for select/poll.
509 */
510 int
511 vop_nopoll(ap)
512 struct vop_poll_args /* {
513 struct vnode *a_vp;
514 int a_events;
515 struct ucred *a_cred;
516 struct thread *a_td;
517 } */ *ap;
518 {
519
520 return (poll_no_poll(ap->a_events));
521 }
522
523 /*
524 * Implement poll for local filesystems that support it.
525 */
526 int
527 vop_stdpoll(ap)
528 struct vop_poll_args /* {
529 struct vnode *a_vp;
530 int a_events;
531 struct ucred *a_cred;
532 struct thread *a_td;
533 } */ *ap;
534 {
535 if (ap->a_events & ~POLLSTANDARD)
536 return (vn_pollrecord(ap->a_vp, ap->a_td, ap->a_events));
537 return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
538 }
539
540 /*
541 * Return our mount point, as we will take charge of the writes.
542 */
543 int
544 vop_stdgetwritemount(ap)
545 struct vop_getwritemount_args /* {
546 struct vnode *a_vp;
547 struct mount **a_mpp;
548 } */ *ap;
549 {
550 struct mount *mp;
551
552 /*
553 * XXX Since this is called unlocked we may be recycled while
554 * attempting to ref the mount. If this is the case or mountpoint
555 * will be set to NULL. We only have to prevent this call from
556 * returning with a ref to an incorrect mountpoint. It is not
557 * harmful to return with a ref to our previous mountpoint.
558 */
559 mp = ap->a_vp->v_mount;
560 if (mp != NULL) {
561 vfs_ref(mp);
562 if (mp != ap->a_vp->v_mount) {
563 vfs_rel(mp);
564 mp = NULL;
565 }
566 }
567 *(ap->a_mpp) = mp;
568 return (0);
569 }
570
571 /* XXX Needs good comment and VOP_BMAP(9) manpage */
572 int
573 vop_stdbmap(ap)
574 struct vop_bmap_args /* {
575 struct vnode *a_vp;
576 daddr_t a_bn;
577 struct bufobj **a_bop;
578 daddr_t *a_bnp;
579 int *a_runp;
580 int *a_runb;
581 } */ *ap;
582 {
583
584 if (ap->a_bop != NULL)
585 *ap->a_bop = &ap->a_vp->v_bufobj;
586 if (ap->a_bnp != NULL)
587 *ap->a_bnp = ap->a_bn * btodb(ap->a_vp->v_mount->mnt_stat.f_iosize);
588 if (ap->a_runp != NULL)
589 *ap->a_runp = 0;
590 if (ap->a_runb != NULL)
591 *ap->a_runb = 0;
592 return (0);
593 }
594
595 int
596 vop_stdfsync(ap)
597 struct vop_fsync_args /* {
598 struct vnode *a_vp;
599 struct ucred *a_cred;
600 int a_waitfor;
601 struct thread *a_td;
602 } */ *ap;
603 {
604 struct vnode *vp = ap->a_vp;
605 struct buf *bp;
606 struct bufobj *bo;
607 struct buf *nbp;
608 int error = 0;
609 int maxretry = 1000; /* large, arbitrarily chosen */
610
611 bo = &vp->v_bufobj;
612 BO_LOCK(bo);
613 loop1:
614 /*
615 * MARK/SCAN initialization to avoid infinite loops.
616 */
617 TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs) {
618 bp->b_vflags &= ~BV_SCANNED;
619 bp->b_error = 0;
620 }
621
622 /*
623 * Flush all dirty buffers associated with a vnode.
624 */
625 loop2:
626 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
627 if ((bp->b_vflags & BV_SCANNED) != 0)
628 continue;
629 bp->b_vflags |= BV_SCANNED;
630 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL))
631 continue;
632 BO_UNLOCK(bo);
633 KASSERT(bp->b_bufobj == bo,
634 ("bp %p wrong b_bufobj %p should be %p",
635 bp, bp->b_bufobj, bo));
636 if ((bp->b_flags & B_DELWRI) == 0)
637 panic("fsync: not dirty");
638 if ((vp->v_object != NULL) && (bp->b_flags & B_CLUSTEROK)) {
639 vfs_bio_awrite(bp);
640 } else {
641 bremfree(bp);
642 bawrite(bp);
643 }
644 BO_LOCK(bo);
645 goto loop2;
646 }
647
648 /*
649 * If synchronous the caller expects us to completely resolve all
650 * dirty buffers in the system. Wait for in-progress I/O to
651 * complete (which could include background bitmap writes), then
652 * retry if dirty blocks still exist.
653 */
654 if (ap->a_waitfor == MNT_WAIT) {
655 bufobj_wwait(bo, 0, 0);
656 if (bo->bo_dirty.bv_cnt > 0) {
657 /*
658 * If we are unable to write any of these buffers
659 * then we fail now rather than trying endlessly
660 * to write them out.
661 */
662 TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs)
663 if ((error = bp->b_error) == 0)
664 continue;
665 if (error == 0 && --maxretry >= 0)
666 goto loop1;
667 error = EAGAIN;
668 }
669 }
670 BO_UNLOCK(bo);
671 if (error == EAGAIN)
672 vprint("fsync: giving up on dirty", vp);
673
674 return (error);
675 }
676
677 /* XXX Needs good comment and more info in the manpage (VOP_GETPAGES(9)). */
678 int
679 vop_stdgetpages(ap)
680 struct vop_getpages_args /* {
681 struct vnode *a_vp;
682 vm_page_t *a_m;
683 int a_count;
684 int a_reqpage;
685 vm_ooffset_t a_offset;
686 } */ *ap;
687 {
688
689 return vnode_pager_generic_getpages(ap->a_vp, ap->a_m,
690 ap->a_count, ap->a_reqpage);
691 }
692
693 int
694 vop_stdkqfilter(struct vop_kqfilter_args *ap)
695 {
696 return vfs_kqfilter(ap);
697 }
698
699 /* XXX Needs good comment and more info in the manpage (VOP_PUTPAGES(9)). */
700 int
701 vop_stdputpages(ap)
702 struct vop_putpages_args /* {
703 struct vnode *a_vp;
704 vm_page_t *a_m;
705 int a_count;
706 int a_sync;
707 int *a_rtvals;
708 vm_ooffset_t a_offset;
709 } */ *ap;
710 {
711
712 return vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count,
713 ap->a_sync, ap->a_rtvals);
714 }
715
716 int
717 vop_stdvptofh(struct vop_vptofh_args *ap)
718 {
719 return (EOPNOTSUPP);
720 }
721
722 int
723 vop_stdvptocnp(struct vop_vptocnp_args *ap)
724 {
725 struct vnode *vp = ap->a_vp;
726 struct vnode **dvp = ap->a_vpp;
727 struct ucred *cred = ap->a_cred;
728 char *buf = ap->a_buf;
729 int *buflen = ap->a_buflen;
730 char *dirbuf, *cpos;
731 int i, error, eofflag, dirbuflen, flags, locked, len, covered;
732 off_t off;
733 ino_t fileno;
734 struct vattr va;
735 struct nameidata nd;
736 struct thread *td;
737 struct dirent *dp;
738 struct vnode *mvp;
739
740 i = *buflen;
741 error = 0;
742 covered = 0;
743 td = curthread;
744
745 if (vp->v_type != VDIR)
746 return (ENOENT);
747
748 error = VOP_GETATTR(vp, &va, cred);
749 if (error)
750 return (error);
751
752 VREF(vp);
753 locked = VOP_ISLOCKED(vp);
754 VOP_UNLOCK(vp, 0);
755 NDINIT_ATVP(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
756 "..", vp, td);
757 flags = FREAD;
758 error = vn_open_cred(&nd, &flags, 0, VN_OPEN_NOAUDIT, cred, NULL);
759 if (error) {
760 vn_lock(vp, locked | LK_RETRY);
761 return (error);
762 }
763 NDFREE(&nd, NDF_ONLY_PNBUF);
764
765 mvp = *dvp = nd.ni_vp;
766
767 if (vp->v_mount != (*dvp)->v_mount &&
768 ((*dvp)->v_vflag & VV_ROOT) &&
769 ((*dvp)->v_mount->mnt_flag & MNT_UNION)) {
770 *dvp = (*dvp)->v_mount->mnt_vnodecovered;
771 VREF(mvp);
772 VOP_UNLOCK(mvp, 0);
773 vn_close(mvp, FREAD, cred, td);
774 VREF(*dvp);
775 vn_lock(*dvp, LK_EXCLUSIVE | LK_RETRY);
776 covered = 1;
777 }
778
779 fileno = va.va_fileid;
780
781 dirbuflen = DEV_BSIZE;
782 if (dirbuflen < va.va_blocksize)
783 dirbuflen = va.va_blocksize;
784 dirbuf = (char *)malloc(dirbuflen, M_TEMP, M_WAITOK);
785
786 if ((*dvp)->v_type != VDIR) {
787 error = ENOENT;
788 goto out;
789 }
790
791 off = 0;
792 len = 0;
793 do {
794 /* call VOP_READDIR of parent */
795 error = get_next_dirent(*dvp, &dp, dirbuf, dirbuflen, &off,
796 &cpos, &len, &eofflag, td);
797 if (error)
798 goto out;
799
800 if ((dp->d_type != DT_WHT) &&
801 (dp->d_fileno == fileno)) {
802 if (covered) {
803 VOP_UNLOCK(*dvp, 0);
804 vn_lock(mvp, LK_EXCLUSIVE | LK_RETRY);
805 if (dirent_exists(mvp, dp->d_name, td)) {
806 error = ENOENT;
807 VOP_UNLOCK(mvp, 0);
808 vn_lock(*dvp, LK_EXCLUSIVE | LK_RETRY);
809 goto out;
810 }
811 VOP_UNLOCK(mvp, 0);
812 vn_lock(*dvp, LK_EXCLUSIVE | LK_RETRY);
813 }
814 i -= dp->d_namlen;
815
816 if (i < 0) {
817 error = ENOMEM;
818 goto out;
819 }
820 bcopy(dp->d_name, buf + i, dp->d_namlen);
821 error = 0;
822 goto out;
823 }
824 } while (len > 0 || !eofflag);
825 error = ENOENT;
826
827 out:
828 free(dirbuf, M_TEMP);
829 if (!error) {
830 *buflen = i;
831 vhold(*dvp);
832 }
833 if (covered) {
834 vput(*dvp);
835 vrele(mvp);
836 } else {
837 VOP_UNLOCK(mvp, 0);
838 vn_close(mvp, FREAD, cred, td);
839 }
840 vn_lock(vp, locked | LK_RETRY);
841 return (error);
842 }
843
844 /*
845 * vfs default ops
846 * used to fill the vfs function table to get reasonable default return values.
847 */
848 int
849 vfs_stdroot (mp, flags, vpp)
850 struct mount *mp;
851 int flags;
852 struct vnode **vpp;
853 {
854
855 return (EOPNOTSUPP);
856 }
857
858 int
859 vfs_stdstatfs (mp, sbp)
860 struct mount *mp;
861 struct statfs *sbp;
862 {
863
864 return (EOPNOTSUPP);
865 }
866
867 int
868 vfs_stdquotactl (mp, cmds, uid, arg)
869 struct mount *mp;
870 int cmds;
871 uid_t uid;
872 void *arg;
873 {
874
875 return (EOPNOTSUPP);
876 }
877
878 int
879 vfs_stdsync(mp, waitfor)
880 struct mount *mp;
881 int waitfor;
882 {
883 struct vnode *vp, *mvp;
884 struct thread *td;
885 int error, lockreq, allerror = 0;
886
887 td = curthread;
888 lockreq = LK_EXCLUSIVE | LK_INTERLOCK;
889 if (waitfor != MNT_WAIT)
890 lockreq |= LK_NOWAIT;
891 /*
892 * Force stale buffer cache information to be flushed.
893 */
894 MNT_ILOCK(mp);
895 loop:
896 MNT_VNODE_FOREACH(vp, mp, mvp) {
897 /* bv_cnt is an acceptable race here. */
898 if (vp->v_bufobj.bo_dirty.bv_cnt == 0)
899 continue;
900 VI_LOCK(vp);
901 MNT_IUNLOCK(mp);
902 if ((error = vget(vp, lockreq, td)) != 0) {
903 MNT_ILOCK(mp);
904 if (error == ENOENT) {
905 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp);
906 goto loop;
907 }
908 continue;
909 }
910 error = VOP_FSYNC(vp, waitfor, td);
911 if (error)
912 allerror = error;
913
914 /* Do not turn this into vput. td is not always curthread. */
915 VOP_UNLOCK(vp, 0);
916 vrele(vp);
917 MNT_ILOCK(mp);
918 }
919 MNT_IUNLOCK(mp);
920 return (allerror);
921 }
922
923 int
924 vfs_stdnosync (mp, waitfor)
925 struct mount *mp;
926 int waitfor;
927 {
928
929 return (0);
930 }
931
932 int
933 vfs_stdvget (mp, ino, flags, vpp)
934 struct mount *mp;
935 ino_t ino;
936 int flags;
937 struct vnode **vpp;
938 {
939
940 return (EOPNOTSUPP);
941 }
942
943 int
944 vfs_stdfhtovp (mp, fhp, vpp)
945 struct mount *mp;
946 struct fid *fhp;
947 struct vnode **vpp;
948 {
949
950 return (EOPNOTSUPP);
951 }
952
953 int
954 vfs_stdinit (vfsp)
955 struct vfsconf *vfsp;
956 {
957
958 return (0);
959 }
960
961 int
962 vfs_stduninit (vfsp)
963 struct vfsconf *vfsp;
964 {
965
966 return(0);
967 }
968
969 int
970 vfs_stdextattrctl(mp, cmd, filename_vp, attrnamespace, attrname)
971 struct mount *mp;
972 int cmd;
973 struct vnode *filename_vp;
974 int attrnamespace;
975 const char *attrname;
976 {
977
978 if (filename_vp != NULL)
979 VOP_UNLOCK(filename_vp, 0);
980 return (EOPNOTSUPP);
981 }
982
983 int
984 vfs_stdsysctl(mp, op, req)
985 struct mount *mp;
986 fsctlop_t op;
987 struct sysctl_req *req;
988 {
989
990 return (EOPNOTSUPP);
991 }
992
993 /* end of vfs default ops */
Cache object: 59ae36adea4f3ce81f559fbce7065b41
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