xref: /freebsd/sys/kern/vfs_default.c (revision bb15ca603fa442c72dde3f3cb8b46db6970e3950)
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("$FreeBSD$");
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_advise =		vop_stdadvise,
100 	.vop_advlock =		vop_stdadvlock,
101 	.vop_advlockasync =	vop_stdadvlockasync,
102 	.vop_advlockpurge =	vop_stdadvlockpurge,
103 	.vop_allocate =		vop_stdallocate,
104 	.vop_bmap =		vop_stdbmap,
105 	.vop_close =		VOP_NULL,
106 	.vop_fsync =		VOP_NULL,
107 	.vop_getpages =		vop_stdgetpages,
108 	.vop_getwritemount = 	vop_stdgetwritemount,
109 	.vop_inactive =		VOP_NULL,
110 	.vop_ioctl =		VOP_ENOTTY,
111 	.vop_kqfilter =		vop_stdkqfilter,
112 	.vop_islocked =		vop_stdislocked,
113 	.vop_lock1 =		vop_stdlock,
114 	.vop_lookup =		vop_nolookup,
115 	.vop_open =		VOP_NULL,
116 	.vop_pathconf =		VOP_EINVAL,
117 	.vop_poll =		vop_nopoll,
118 	.vop_putpages =		vop_stdputpages,
119 	.vop_readlink =		VOP_EINVAL,
120 	.vop_rename =		vop_norename,
121 	.vop_revoke =		VOP_PANIC,
122 	.vop_strategy =		vop_nostrategy,
123 	.vop_unlock =		vop_stdunlock,
124 	.vop_vptocnp =		vop_stdvptocnp,
125 	.vop_vptofh =		vop_stdvptofh,
126 };
127 
128 /*
129  * Series of placeholder functions for various error returns for
130  * VOPs.
131  */
132 
133 int
134 vop_eopnotsupp(struct vop_generic_args *ap)
135 {
136 	/*
137 	printf("vop_notsupp[%s]\n", ap->a_desc->vdesc_name);
138 	*/
139 
140 	return (EOPNOTSUPP);
141 }
142 
143 int
144 vop_ebadf(struct vop_generic_args *ap)
145 {
146 
147 	return (EBADF);
148 }
149 
150 int
151 vop_enotty(struct vop_generic_args *ap)
152 {
153 
154 	return (ENOTTY);
155 }
156 
157 int
158 vop_einval(struct vop_generic_args *ap)
159 {
160 
161 	return (EINVAL);
162 }
163 
164 int
165 vop_enoent(struct vop_generic_args *ap)
166 {
167 
168 	return (ENOENT);
169 }
170 
171 int
172 vop_null(struct vop_generic_args *ap)
173 {
174 
175 	return (0);
176 }
177 
178 /*
179  * Helper function to panic on some bad VOPs in some filesystems.
180  */
181 int
182 vop_panic(struct vop_generic_args *ap)
183 {
184 
185 	panic("filesystem goof: vop_panic[%s]", ap->a_desc->vdesc_name);
186 }
187 
188 /*
189  * vop_std<something> and vop_no<something> are default functions for use by
190  * filesystems that need the "default reasonable" implementation for a
191  * particular operation.
192  *
193  * The documentation for the operations they implement exists (if it exists)
194  * in the VOP_<SOMETHING>(9) manpage (all uppercase).
195  */
196 
197 /*
198  * Default vop for filesystems that do not support name lookup
199  */
200 static int
201 vop_nolookup(ap)
202 	struct vop_lookup_args /* {
203 		struct vnode *a_dvp;
204 		struct vnode **a_vpp;
205 		struct componentname *a_cnp;
206 	} */ *ap;
207 {
208 
209 	*ap->a_vpp = NULL;
210 	return (ENOTDIR);
211 }
212 
213 /*
214  * vop_norename:
215  *
216  * Handle unlock and reference counting for arguments of vop_rename
217  * for filesystems that do not implement rename operation.
218  */
219 static int
220 vop_norename(struct vop_rename_args *ap)
221 {
222 
223 	vop_rename_fail(ap);
224 	return (EOPNOTSUPP);
225 }
226 
227 /*
228  *	vop_nostrategy:
229  *
230  *	Strategy routine for VFS devices that have none.
231  *
232  *	BIO_ERROR and B_INVAL must be cleared prior to calling any strategy
233  *	routine.  Typically this is done for a BIO_READ strategy call.
234  *	Typically B_INVAL is assumed to already be clear prior to a write
235  *	and should not be cleared manually unless you just made the buffer
236  *	invalid.  BIO_ERROR should be cleared either way.
237  */
238 
239 static int
240 vop_nostrategy (struct vop_strategy_args *ap)
241 {
242 	printf("No strategy for buffer at %p\n", ap->a_bp);
243 	vprint("vnode", ap->a_vp);
244 	ap->a_bp->b_ioflags |= BIO_ERROR;
245 	ap->a_bp->b_error = EOPNOTSUPP;
246 	bufdone(ap->a_bp);
247 	return (EOPNOTSUPP);
248 }
249 
250 static int
251 get_next_dirent(struct vnode *vp, struct dirent **dpp, char *dirbuf,
252 		int dirbuflen, off_t *off, char **cpos, int *len,
253 		int *eofflag, struct thread *td)
254 {
255 	int error, reclen;
256 	struct uio uio;
257 	struct iovec iov;
258 	struct dirent *dp;
259 
260 	KASSERT(VOP_ISLOCKED(vp), ("vp %p is not locked", vp));
261 	KASSERT(vp->v_type == VDIR, ("vp %p is not a directory", vp));
262 
263 	if (*len == 0) {
264 		iov.iov_base = dirbuf;
265 		iov.iov_len = dirbuflen;
266 
267 		uio.uio_iov = &iov;
268 		uio.uio_iovcnt = 1;
269 		uio.uio_offset = *off;
270 		uio.uio_resid = dirbuflen;
271 		uio.uio_segflg = UIO_SYSSPACE;
272 		uio.uio_rw = UIO_READ;
273 		uio.uio_td = td;
274 
275 		*eofflag = 0;
276 
277 #ifdef MAC
278 		error = mac_vnode_check_readdir(td->td_ucred, vp);
279 		if (error == 0)
280 #endif
281 			error = VOP_READDIR(vp, &uio, td->td_ucred, eofflag,
282 		    		NULL, NULL);
283 		if (error)
284 			return (error);
285 
286 		*off = uio.uio_offset;
287 
288 		*cpos = dirbuf;
289 		*len = (dirbuflen - uio.uio_resid);
290 
291 		if (*len == 0)
292 			return (ENOENT);
293 	}
294 
295 	dp = (struct dirent *)(*cpos);
296 	reclen = dp->d_reclen;
297 	*dpp = dp;
298 
299 	/* check for malformed directory.. */
300 	if (reclen < DIRENT_MINSIZE)
301 		return (EINVAL);
302 
303 	*cpos += reclen;
304 	*len -= reclen;
305 
306 	return (0);
307 }
308 
309 /*
310  * Check if a named file exists in a given directory vnode.
311  */
312 static int
313 dirent_exists(struct vnode *vp, const char *dirname, struct thread *td)
314 {
315 	char *dirbuf, *cpos;
316 	int error, eofflag, dirbuflen, len, found;
317 	off_t off;
318 	struct dirent *dp;
319 	struct vattr va;
320 
321 	KASSERT(VOP_ISLOCKED(vp), ("vp %p is not locked", vp));
322 	KASSERT(vp->v_type == VDIR, ("vp %p is not a directory", vp));
323 
324 	found = 0;
325 
326 	error = VOP_GETATTR(vp, &va, td->td_ucred);
327 	if (error)
328 		return (found);
329 
330 	dirbuflen = DEV_BSIZE;
331 	if (dirbuflen < va.va_blocksize)
332 		dirbuflen = va.va_blocksize;
333 	dirbuf = (char *)malloc(dirbuflen, M_TEMP, M_WAITOK);
334 
335 	off = 0;
336 	len = 0;
337 	do {
338 		error = get_next_dirent(vp, &dp, dirbuf, dirbuflen, &off,
339 					&cpos, &len, &eofflag, td);
340 		if (error)
341 			goto out;
342 
343 		if ((dp->d_type != DT_WHT) &&
344 		    !strcmp(dp->d_name, dirname)) {
345 			found = 1;
346 			goto out;
347 		}
348 	} while (len > 0 || !eofflag);
349 
350 out:
351 	free(dirbuf, M_TEMP);
352 	return (found);
353 }
354 
355 int
356 vop_stdaccess(struct vop_access_args *ap)
357 {
358 
359 	KASSERT((ap->a_accmode & ~(VEXEC | VWRITE | VREAD | VADMIN |
360 	    VAPPEND)) == 0, ("invalid bit in accmode"));
361 
362 	return (VOP_ACCESSX(ap->a_vp, ap->a_accmode, ap->a_cred, ap->a_td));
363 }
364 
365 int
366 vop_stdaccessx(struct vop_accessx_args *ap)
367 {
368 	int error;
369 	accmode_t accmode = ap->a_accmode;
370 
371 	error = vfs_unixify_accmode(&accmode);
372 	if (error != 0)
373 		return (error);
374 
375 	if (accmode == 0)
376 		return (0);
377 
378 	return (VOP_ACCESS(ap->a_vp, accmode, ap->a_cred, ap->a_td));
379 }
380 
381 /*
382  * Advisory record locking support
383  */
384 int
385 vop_stdadvlock(struct vop_advlock_args *ap)
386 {
387 	struct vnode *vp;
388 	struct ucred *cred;
389 	struct vattr vattr;
390 	int error;
391 
392 	vp = ap->a_vp;
393 	cred = curthread->td_ucred;
394 	vn_lock(vp, LK_SHARED | LK_RETRY);
395 	error = VOP_GETATTR(vp, &vattr, cred);
396 	VOP_UNLOCK(vp, 0);
397 	if (error)
398 		return (error);
399 
400 	return (lf_advlock(ap, &(vp->v_lockf), vattr.va_size));
401 }
402 
403 int
404 vop_stdadvlockasync(struct vop_advlockasync_args *ap)
405 {
406 	struct vnode *vp;
407 	struct ucred *cred;
408 	struct vattr vattr;
409 	int error;
410 
411 	vp = ap->a_vp;
412 	cred = curthread->td_ucred;
413 	vn_lock(vp, LK_SHARED | LK_RETRY);
414 	error = VOP_GETATTR(vp, &vattr, cred);
415 	VOP_UNLOCK(vp, 0);
416 	if (error)
417 		return (error);
418 
419 	return (lf_advlockasync(ap, &(vp->v_lockf), vattr.va_size));
420 }
421 
422 int
423 vop_stdadvlockpurge(struct vop_advlockpurge_args *ap)
424 {
425 	struct vnode *vp;
426 
427 	vp = ap->a_vp;
428 	lf_purgelocks(vp, &vp->v_lockf);
429 	return (0);
430 }
431 
432 /*
433  * vop_stdpathconf:
434  *
435  * Standard implementation of POSIX pathconf, to get information about limits
436  * for a filesystem.
437  * Override per filesystem for the case where the filesystem has smaller
438  * limits.
439  */
440 int
441 vop_stdpathconf(ap)
442 	struct vop_pathconf_args /* {
443 	struct vnode *a_vp;
444 	int a_name;
445 	int *a_retval;
446 	} */ *ap;
447 {
448 
449 	switch (ap->a_name) {
450 		case _PC_NAME_MAX:
451 			*ap->a_retval = NAME_MAX;
452 			return (0);
453 		case _PC_PATH_MAX:
454 			*ap->a_retval = PATH_MAX;
455 			return (0);
456 		case _PC_LINK_MAX:
457 			*ap->a_retval = LINK_MAX;
458 			return (0);
459 		case _PC_MAX_CANON:
460 			*ap->a_retval = MAX_CANON;
461 			return (0);
462 		case _PC_MAX_INPUT:
463 			*ap->a_retval = MAX_INPUT;
464 			return (0);
465 		case _PC_PIPE_BUF:
466 			*ap->a_retval = PIPE_BUF;
467 			return (0);
468 		case _PC_CHOWN_RESTRICTED:
469 			*ap->a_retval = 1;
470 			return (0);
471 		case _PC_VDISABLE:
472 			*ap->a_retval = _POSIX_VDISABLE;
473 			return (0);
474 		default:
475 			return (EINVAL);
476 	}
477 	/* NOTREACHED */
478 }
479 
480 /*
481  * Standard lock, unlock and islocked functions.
482  */
483 int
484 vop_stdlock(ap)
485 	struct vop_lock1_args /* {
486 		struct vnode *a_vp;
487 		int a_flags;
488 		char *file;
489 		int line;
490 	} */ *ap;
491 {
492 	struct vnode *vp = ap->a_vp;
493 
494 	return (_lockmgr_args(vp->v_vnlock, ap->a_flags, VI_MTX(vp),
495 	    LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, ap->a_file,
496 	    ap->a_line));
497 }
498 
499 /* See above. */
500 int
501 vop_stdunlock(ap)
502 	struct vop_unlock_args /* {
503 		struct vnode *a_vp;
504 		int a_flags;
505 	} */ *ap;
506 {
507 	struct vnode *vp = ap->a_vp;
508 
509 	return (lockmgr(vp->v_vnlock, ap->a_flags | LK_RELEASE, VI_MTX(vp)));
510 }
511 
512 /* See above. */
513 int
514 vop_stdislocked(ap)
515 	struct vop_islocked_args /* {
516 		struct vnode *a_vp;
517 	} */ *ap;
518 {
519 
520 	return (lockstatus(ap->a_vp->v_vnlock));
521 }
522 
523 /*
524  * Return true for select/poll.
525  */
526 int
527 vop_nopoll(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 
536 	return (poll_no_poll(ap->a_events));
537 }
538 
539 /*
540  * Implement poll for local filesystems that support it.
541  */
542 int
543 vop_stdpoll(ap)
544 	struct vop_poll_args /* {
545 		struct vnode *a_vp;
546 		int  a_events;
547 		struct ucred *a_cred;
548 		struct thread *a_td;
549 	} */ *ap;
550 {
551 	if (ap->a_events & ~POLLSTANDARD)
552 		return (vn_pollrecord(ap->a_vp, ap->a_td, ap->a_events));
553 	return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
554 }
555 
556 /*
557  * Return our mount point, as we will take charge of the writes.
558  */
559 int
560 vop_stdgetwritemount(ap)
561 	struct vop_getwritemount_args /* {
562 		struct vnode *a_vp;
563 		struct mount **a_mpp;
564 	} */ *ap;
565 {
566 	struct mount *mp;
567 
568 	/*
569 	 * XXX Since this is called unlocked we may be recycled while
570 	 * attempting to ref the mount.  If this is the case or mountpoint
571 	 * will be set to NULL.  We only have to prevent this call from
572 	 * returning with a ref to an incorrect mountpoint.  It is not
573 	 * harmful to return with a ref to our previous mountpoint.
574 	 */
575 	mp = ap->a_vp->v_mount;
576 	if (mp != NULL) {
577 		vfs_ref(mp);
578 		if (mp != ap->a_vp->v_mount) {
579 			vfs_rel(mp);
580 			mp = NULL;
581 		}
582 	}
583 	*(ap->a_mpp) = mp;
584 	return (0);
585 }
586 
587 /* XXX Needs good comment and VOP_BMAP(9) manpage */
588 int
589 vop_stdbmap(ap)
590 	struct vop_bmap_args /* {
591 		struct vnode *a_vp;
592 		daddr_t  a_bn;
593 		struct bufobj **a_bop;
594 		daddr_t *a_bnp;
595 		int *a_runp;
596 		int *a_runb;
597 	} */ *ap;
598 {
599 
600 	if (ap->a_bop != NULL)
601 		*ap->a_bop = &ap->a_vp->v_bufobj;
602 	if (ap->a_bnp != NULL)
603 		*ap->a_bnp = ap->a_bn * btodb(ap->a_vp->v_mount->mnt_stat.f_iosize);
604 	if (ap->a_runp != NULL)
605 		*ap->a_runp = 0;
606 	if (ap->a_runb != NULL)
607 		*ap->a_runb = 0;
608 	return (0);
609 }
610 
611 int
612 vop_stdfsync(ap)
613 	struct vop_fsync_args /* {
614 		struct vnode *a_vp;
615 		struct ucred *a_cred;
616 		int a_waitfor;
617 		struct thread *a_td;
618 	} */ *ap;
619 {
620 	struct vnode *vp = ap->a_vp;
621 	struct buf *bp;
622 	struct bufobj *bo;
623 	struct buf *nbp;
624 	int error = 0;
625 	int maxretry = 1000;     /* large, arbitrarily chosen */
626 
627 	bo = &vp->v_bufobj;
628 	BO_LOCK(bo);
629 loop1:
630 	/*
631 	 * MARK/SCAN initialization to avoid infinite loops.
632 	 */
633         TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs) {
634                 bp->b_vflags &= ~BV_SCANNED;
635 		bp->b_error = 0;
636 	}
637 
638 	/*
639 	 * Flush all dirty buffers associated with a vnode.
640 	 */
641 loop2:
642 	TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
643 		if ((bp->b_vflags & BV_SCANNED) != 0)
644 			continue;
645 		bp->b_vflags |= BV_SCANNED;
646 		if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL))
647 			continue;
648 		BO_UNLOCK(bo);
649 		KASSERT(bp->b_bufobj == bo,
650 		    ("bp %p wrong b_bufobj %p should be %p",
651 		    bp, bp->b_bufobj, bo));
652 		if ((bp->b_flags & B_DELWRI) == 0)
653 			panic("fsync: not dirty");
654 		if ((vp->v_object != NULL) && (bp->b_flags & B_CLUSTEROK)) {
655 			vfs_bio_awrite(bp);
656 		} else {
657 			bremfree(bp);
658 			bawrite(bp);
659 		}
660 		BO_LOCK(bo);
661 		goto loop2;
662 	}
663 
664 	/*
665 	 * If synchronous the caller expects us to completely resolve all
666 	 * dirty buffers in the system.  Wait for in-progress I/O to
667 	 * complete (which could include background bitmap writes), then
668 	 * retry if dirty blocks still exist.
669 	 */
670 	if (ap->a_waitfor == MNT_WAIT) {
671 		bufobj_wwait(bo, 0, 0);
672 		if (bo->bo_dirty.bv_cnt > 0) {
673 			/*
674 			 * If we are unable to write any of these buffers
675 			 * then we fail now rather than trying endlessly
676 			 * to write them out.
677 			 */
678 			TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs)
679 				if ((error = bp->b_error) == 0)
680 					continue;
681 			if (error == 0 && --maxretry >= 0)
682 				goto loop1;
683 			error = EAGAIN;
684 		}
685 	}
686 	BO_UNLOCK(bo);
687 	if (error == EAGAIN)
688 		vprint("fsync: giving up on dirty", vp);
689 
690 	return (error);
691 }
692 
693 /* XXX Needs good comment and more info in the manpage (VOP_GETPAGES(9)). */
694 int
695 vop_stdgetpages(ap)
696 	struct vop_getpages_args /* {
697 		struct vnode *a_vp;
698 		vm_page_t *a_m;
699 		int a_count;
700 		int a_reqpage;
701 		vm_ooffset_t a_offset;
702 	} */ *ap;
703 {
704 
705 	return vnode_pager_generic_getpages(ap->a_vp, ap->a_m,
706 	    ap->a_count, ap->a_reqpage);
707 }
708 
709 int
710 vop_stdkqfilter(struct vop_kqfilter_args *ap)
711 {
712 	return vfs_kqfilter(ap);
713 }
714 
715 /* XXX Needs good comment and more info in the manpage (VOP_PUTPAGES(9)). */
716 int
717 vop_stdputpages(ap)
718 	struct vop_putpages_args /* {
719 		struct vnode *a_vp;
720 		vm_page_t *a_m;
721 		int a_count;
722 		int a_sync;
723 		int *a_rtvals;
724 		vm_ooffset_t a_offset;
725 	} */ *ap;
726 {
727 
728 	return vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count,
729 	     ap->a_sync, ap->a_rtvals);
730 }
731 
732 int
733 vop_stdvptofh(struct vop_vptofh_args *ap)
734 {
735 	return (EOPNOTSUPP);
736 }
737 
738 int
739 vop_stdvptocnp(struct vop_vptocnp_args *ap)
740 {
741 	struct vnode *vp = ap->a_vp;
742 	struct vnode **dvp = ap->a_vpp;
743 	struct ucred *cred = ap->a_cred;
744 	char *buf = ap->a_buf;
745 	int *buflen = ap->a_buflen;
746 	char *dirbuf, *cpos;
747 	int i, error, eofflag, dirbuflen, flags, locked, len, covered;
748 	off_t off;
749 	ino_t fileno;
750 	struct vattr va;
751 	struct nameidata nd;
752 	struct thread *td;
753 	struct dirent *dp;
754 	struct vnode *mvp;
755 
756 	i = *buflen;
757 	error = 0;
758 	covered = 0;
759 	td = curthread;
760 
761 	if (vp->v_type != VDIR)
762 		return (ENOENT);
763 
764 	error = VOP_GETATTR(vp, &va, cred);
765 	if (error)
766 		return (error);
767 
768 	VREF(vp);
769 	locked = VOP_ISLOCKED(vp);
770 	VOP_UNLOCK(vp, 0);
771 	NDINIT_ATVP(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
772 	    "..", vp, td);
773 	flags = FREAD;
774 	error = vn_open_cred(&nd, &flags, 0, VN_OPEN_NOAUDIT, cred, NULL);
775 	if (error) {
776 		vn_lock(vp, locked | LK_RETRY);
777 		return (error);
778 	}
779 	NDFREE(&nd, NDF_ONLY_PNBUF);
780 
781 	mvp = *dvp = nd.ni_vp;
782 
783 	if (vp->v_mount != (*dvp)->v_mount &&
784 	    ((*dvp)->v_vflag & VV_ROOT) &&
785 	    ((*dvp)->v_mount->mnt_flag & MNT_UNION)) {
786 		*dvp = (*dvp)->v_mount->mnt_vnodecovered;
787 		VREF(mvp);
788 		VOP_UNLOCK(mvp, 0);
789 		vn_close(mvp, FREAD, cred, td);
790 		VREF(*dvp);
791 		vn_lock(*dvp, LK_EXCLUSIVE | LK_RETRY);
792 		covered = 1;
793 	}
794 
795 	fileno = va.va_fileid;
796 
797 	dirbuflen = DEV_BSIZE;
798 	if (dirbuflen < va.va_blocksize)
799 		dirbuflen = va.va_blocksize;
800 	dirbuf = (char *)malloc(dirbuflen, M_TEMP, M_WAITOK);
801 
802 	if ((*dvp)->v_type != VDIR) {
803 		error = ENOENT;
804 		goto out;
805 	}
806 
807 	off = 0;
808 	len = 0;
809 	do {
810 		/* call VOP_READDIR of parent */
811 		error = get_next_dirent(*dvp, &dp, dirbuf, dirbuflen, &off,
812 					&cpos, &len, &eofflag, td);
813 		if (error)
814 			goto out;
815 
816 		if ((dp->d_type != DT_WHT) &&
817 		    (dp->d_fileno == fileno)) {
818 			if (covered) {
819 				VOP_UNLOCK(*dvp, 0);
820 				vn_lock(mvp, LK_EXCLUSIVE | LK_RETRY);
821 				if (dirent_exists(mvp, dp->d_name, td)) {
822 					error = ENOENT;
823 					VOP_UNLOCK(mvp, 0);
824 					vn_lock(*dvp, LK_EXCLUSIVE | LK_RETRY);
825 					goto out;
826 				}
827 				VOP_UNLOCK(mvp, 0);
828 				vn_lock(*dvp, LK_EXCLUSIVE | LK_RETRY);
829 			}
830 			i -= dp->d_namlen;
831 
832 			if (i < 0) {
833 				error = ENOMEM;
834 				goto out;
835 			}
836 			bcopy(dp->d_name, buf + i, dp->d_namlen);
837 			error = 0;
838 			goto out;
839 		}
840 	} while (len > 0 || !eofflag);
841 	error = ENOENT;
842 
843 out:
844 	free(dirbuf, M_TEMP);
845 	if (!error) {
846 		*buflen = i;
847 		vref(*dvp);
848 	}
849 	if (covered) {
850 		vput(*dvp);
851 		vrele(mvp);
852 	} else {
853 		VOP_UNLOCK(mvp, 0);
854 		vn_close(mvp, FREAD, cred, td);
855 	}
856 	vn_lock(vp, locked | LK_RETRY);
857 	return (error);
858 }
859 
860 int
861 vop_stdallocate(struct vop_allocate_args *ap)
862 {
863 #ifdef __notyet__
864 	struct statfs sfs;
865 #endif
866 	struct iovec aiov;
867 	struct vattr vattr, *vap;
868 	struct uio auio;
869 	off_t fsize, len, cur, offset;
870 	uint8_t *buf;
871 	struct thread *td;
872 	struct vnode *vp;
873 	size_t iosize;
874 	int error;
875 
876 	buf = NULL;
877 	error = 0;
878 	td = curthread;
879 	vap = &vattr;
880 	vp = ap->a_vp;
881 	len = *ap->a_len;
882 	offset = *ap->a_offset;
883 
884 	error = VOP_GETATTR(vp, vap, td->td_ucred);
885 	if (error != 0)
886 		goto out;
887 	fsize = vap->va_size;
888 	iosize = vap->va_blocksize;
889 	if (iosize == 0)
890 		iosize = BLKDEV_IOSIZE;
891 	if (iosize > MAXPHYS)
892 		iosize = MAXPHYS;
893 	buf = malloc(iosize, M_TEMP, M_WAITOK);
894 
895 #ifdef __notyet__
896 	/*
897 	 * Check if the filesystem sets f_maxfilesize; if not use
898 	 * VOP_SETATTR to perform the check.
899 	 */
900 	error = VFS_STATFS(vp->v_mount, &sfs, td);
901 	if (error != 0)
902 		goto out;
903 	if (sfs.f_maxfilesize) {
904 		if (offset > sfs.f_maxfilesize || len > sfs.f_maxfilesize ||
905 		    offset + len > sfs.f_maxfilesize) {
906 			error = EFBIG;
907 			goto out;
908 		}
909 	} else
910 #endif
911 	if (offset + len > vap->va_size) {
912 		/*
913 		 * Test offset + len against the filesystem's maxfilesize.
914 		 */
915 		VATTR_NULL(vap);
916 		vap->va_size = offset + len;
917 		error = VOP_SETATTR(vp, vap, td->td_ucred);
918 		if (error != 0)
919 			goto out;
920 		VATTR_NULL(vap);
921 		vap->va_size = fsize;
922 		error = VOP_SETATTR(vp, vap, td->td_ucred);
923 		if (error != 0)
924 			goto out;
925 	}
926 
927 	for (;;) {
928 		/*
929 		 * Read and write back anything below the nominal file
930 		 * size.  There's currently no way outside the filesystem
931 		 * to know whether this area is sparse or not.
932 		 */
933 		cur = iosize;
934 		if ((offset % iosize) != 0)
935 			cur -= (offset % iosize);
936 		if (cur > len)
937 			cur = len;
938 		if (offset < fsize) {
939 			aiov.iov_base = buf;
940 			aiov.iov_len = cur;
941 			auio.uio_iov = &aiov;
942 			auio.uio_iovcnt = 1;
943 			auio.uio_offset = offset;
944 			auio.uio_resid = cur;
945 			auio.uio_segflg = UIO_SYSSPACE;
946 			auio.uio_rw = UIO_READ;
947 			auio.uio_td = td;
948 			error = VOP_READ(vp, &auio, 0, td->td_ucred);
949 			if (error != 0)
950 				break;
951 			if (auio.uio_resid > 0) {
952 				bzero(buf + cur - auio.uio_resid,
953 				    auio.uio_resid);
954 			}
955 		} else {
956 			bzero(buf, cur);
957 		}
958 
959 		aiov.iov_base = buf;
960 		aiov.iov_len = cur;
961 		auio.uio_iov = &aiov;
962 		auio.uio_iovcnt = 1;
963 		auio.uio_offset = offset;
964 		auio.uio_resid = cur;
965 		auio.uio_segflg = UIO_SYSSPACE;
966 		auio.uio_rw = UIO_WRITE;
967 		auio.uio_td = td;
968 
969 		error = VOP_WRITE(vp, &auio, 0, td->td_ucred);
970 		if (error != 0)
971 			break;
972 
973 		len -= cur;
974 		offset += cur;
975 		if (len == 0)
976 			break;
977 		if (should_yield())
978 			break;
979 	}
980 
981  out:
982 	*ap->a_len = len;
983 	*ap->a_offset = offset;
984 	free(buf, M_TEMP);
985 	return (error);
986 }
987 
988 int
989 vop_stdadvise(struct vop_advise_args *ap)
990 {
991 	struct vnode *vp;
992 	off_t start, end;
993 	int error, vfslocked;
994 
995 	vp = ap->a_vp;
996 	switch (ap->a_advice) {
997 	case POSIX_FADV_WILLNEED:
998 		/*
999 		 * Do nothing for now.  Filesystems should provide a
1000 		 * custom method which starts an asynchronous read of
1001 		 * the requested region.
1002 		 */
1003 		error = 0;
1004 		break;
1005 	case POSIX_FADV_DONTNEED:
1006 		/*
1007 		 * Flush any open FS buffers and then remove pages
1008 		 * from the backing VM object.  Using vinvalbuf() here
1009 		 * is a bit heavy-handed as it flushes all buffers for
1010 		 * the given vnode, not just the buffers covering the
1011 		 * requested range.
1012 		 */
1013 		error = 0;
1014 		vfslocked = VFS_LOCK_GIANT(vp->v_mount);
1015 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1016 		if (vp->v_iflag & VI_DOOMED) {
1017 			VOP_UNLOCK(vp, 0);
1018 			VFS_UNLOCK_GIANT(vfslocked);
1019 			break;
1020 		}
1021 		vinvalbuf(vp, V_CLEANONLY, 0, 0);
1022 		if (vp->v_object != NULL) {
1023 			start = trunc_page(ap->a_start);
1024 			end = round_page(ap->a_end);
1025 			VM_OBJECT_LOCK(vp->v_object);
1026 			vm_object_page_cache(vp->v_object, OFF_TO_IDX(start),
1027 			    OFF_TO_IDX(end));
1028 			VM_OBJECT_UNLOCK(vp->v_object);
1029 		}
1030 		VOP_UNLOCK(vp, 0);
1031 		VFS_UNLOCK_GIANT(vfslocked);
1032 		break;
1033 	default:
1034 		error = EINVAL;
1035 		break;
1036 	}
1037 	return (error);
1038 }
1039 
1040 /*
1041  * vfs default ops
1042  * used to fill the vfs function table to get reasonable default return values.
1043  */
1044 int
1045 vfs_stdroot (mp, flags, vpp)
1046 	struct mount *mp;
1047 	int flags;
1048 	struct vnode **vpp;
1049 {
1050 
1051 	return (EOPNOTSUPP);
1052 }
1053 
1054 int
1055 vfs_stdstatfs (mp, sbp)
1056 	struct mount *mp;
1057 	struct statfs *sbp;
1058 {
1059 
1060 	return (EOPNOTSUPP);
1061 }
1062 
1063 int
1064 vfs_stdquotactl (mp, cmds, uid, arg)
1065 	struct mount *mp;
1066 	int cmds;
1067 	uid_t uid;
1068 	void *arg;
1069 {
1070 
1071 	return (EOPNOTSUPP);
1072 }
1073 
1074 int
1075 vfs_stdsync(mp, waitfor)
1076 	struct mount *mp;
1077 	int waitfor;
1078 {
1079 	struct vnode *vp, *mvp;
1080 	struct thread *td;
1081 	int error, lockreq, allerror = 0;
1082 
1083 	td = curthread;
1084 	lockreq = LK_EXCLUSIVE | LK_INTERLOCK;
1085 	if (waitfor != MNT_WAIT)
1086 		lockreq |= LK_NOWAIT;
1087 	/*
1088 	 * Force stale buffer cache information to be flushed.
1089 	 */
1090 	MNT_ILOCK(mp);
1091 loop:
1092 	MNT_VNODE_FOREACH(vp, mp, mvp) {
1093 		/* bv_cnt is an acceptable race here. */
1094 		if (vp->v_bufobj.bo_dirty.bv_cnt == 0)
1095 			continue;
1096 		VI_LOCK(vp);
1097 		MNT_IUNLOCK(mp);
1098 		if ((error = vget(vp, lockreq, td)) != 0) {
1099 			MNT_ILOCK(mp);
1100 			if (error == ENOENT) {
1101 				MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp);
1102 				goto loop;
1103 			}
1104 			continue;
1105 		}
1106 		error = VOP_FSYNC(vp, waitfor, td);
1107 		if (error)
1108 			allerror = error;
1109 		vput(vp);
1110 		MNT_ILOCK(mp);
1111 	}
1112 	MNT_IUNLOCK(mp);
1113 	return (allerror);
1114 }
1115 
1116 int
1117 vfs_stdnosync (mp, waitfor)
1118 	struct mount *mp;
1119 	int waitfor;
1120 {
1121 
1122 	return (0);
1123 }
1124 
1125 int
1126 vfs_stdvget (mp, ino, flags, vpp)
1127 	struct mount *mp;
1128 	ino_t ino;
1129 	int flags;
1130 	struct vnode **vpp;
1131 {
1132 
1133 	return (EOPNOTSUPP);
1134 }
1135 
1136 int
1137 vfs_stdfhtovp (mp, fhp, flags, vpp)
1138 	struct mount *mp;
1139 	struct fid *fhp;
1140 	int flags;
1141 	struct vnode **vpp;
1142 {
1143 
1144 	return (EOPNOTSUPP);
1145 }
1146 
1147 int
1148 vfs_stdinit (vfsp)
1149 	struct vfsconf *vfsp;
1150 {
1151 
1152 	return (0);
1153 }
1154 
1155 int
1156 vfs_stduninit (vfsp)
1157 	struct vfsconf *vfsp;
1158 {
1159 
1160 	return(0);
1161 }
1162 
1163 int
1164 vfs_stdextattrctl(mp, cmd, filename_vp, attrnamespace, attrname)
1165 	struct mount *mp;
1166 	int cmd;
1167 	struct vnode *filename_vp;
1168 	int attrnamespace;
1169 	const char *attrname;
1170 {
1171 
1172 	if (filename_vp != NULL)
1173 		VOP_UNLOCK(filename_vp, 0);
1174 	return (EOPNOTSUPP);
1175 }
1176 
1177 int
1178 vfs_stdsysctl(mp, op, req)
1179 	struct mount *mp;
1180 	fsctlop_t op;
1181 	struct sysctl_req *req;
1182 {
1183 
1184 	return (EOPNOTSUPP);
1185 }
1186 
1187 /* end of vfs default ops */
1188