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: stable/11/sys/kern/vfs_default.c 350126 2019-07-19 14:24:33Z asomers $");
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/namei.h>
51#include <sys/rwlock.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
69static int	vop_nolookup(struct vop_lookup_args *);
70static int	vop_norename(struct vop_rename_args *);
71static int	vop_nostrategy(struct vop_strategy_args *);
72static 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);
76static 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
81static int vop_stdis_text(struct vop_is_text_args *ap);
82static int vop_stdset_text(struct vop_set_text_args *ap);
83static int vop_stdunset_text(struct vop_unset_text_args *ap);
84static int vop_stdget_writecount(struct vop_get_writecount_args *ap);
85static int vop_stdadd_writecount(struct vop_add_writecount_args *ap);
86static int vop_stdfdatasync(struct vop_fdatasync_args *ap);
87static int vop_stdgetpages_async(struct vop_getpages_async_args *ap);
88
89/*
90 * This vnode table stores what we want to do if the filesystem doesn't
91 * implement a particular VOP.
92 *
93 * If there is no specific entry here, we will return EOPNOTSUPP.
94 *
95 * Note that every filesystem has to implement either vop_access
96 * or vop_accessx; failing to do so will result in immediate crash
97 * due to stack overflow, as vop_stdaccess() calls vop_stdaccessx(),
98 * which calls vop_stdaccess() etc.
99 */
100
101struct vop_vector default_vnodeops = {
102	.vop_default =		NULL,
103	.vop_bypass =		VOP_EOPNOTSUPP,
104
105	.vop_access =		vop_stdaccess,
106	.vop_accessx =		vop_stdaccessx,
107	.vop_advise =		vop_stdadvise,
108	.vop_advlock =		vop_stdadvlock,
109	.vop_advlockasync =	vop_stdadvlockasync,
110	.vop_advlockpurge =	vop_stdadvlockpurge,
111	.vop_allocate =		vop_stdallocate,
112	.vop_bmap =		vop_stdbmap,
113	.vop_close =		VOP_NULL,
114	.vop_fsync =		VOP_NULL,
115	.vop_fdatasync =	vop_stdfdatasync,
116	.vop_getpages =		vop_stdgetpages,
117	.vop_getpages_async =	vop_stdgetpages_async,
118	.vop_getwritemount = 	vop_stdgetwritemount,
119	.vop_inactive =		VOP_NULL,
120	.vop_ioctl =		VOP_ENOTTY,
121	.vop_kqfilter =		vop_stdkqfilter,
122	.vop_islocked =		vop_stdislocked,
123	.vop_lock1 =		vop_stdlock,
124	.vop_lookup =		vop_nolookup,
125	.vop_open =		VOP_NULL,
126	.vop_pathconf =		VOP_EINVAL,
127	.vop_poll =		vop_nopoll,
128	.vop_putpages =		vop_stdputpages,
129	.vop_readlink =		VOP_EINVAL,
130	.vop_rename =		vop_norename,
131	.vop_revoke =		VOP_PANIC,
132	.vop_strategy =		vop_nostrategy,
133	.vop_unlock =		vop_stdunlock,
134	.vop_vptocnp =		vop_stdvptocnp,
135	.vop_vptofh =		vop_stdvptofh,
136	.vop_unp_bind =		vop_stdunp_bind,
137	.vop_unp_connect =	vop_stdunp_connect,
138	.vop_unp_detach =	vop_stdunp_detach,
139	.vop_is_text =		vop_stdis_text,
140	.vop_set_text =		vop_stdset_text,
141	.vop_unset_text =	vop_stdunset_text,
142	.vop_get_writecount =	vop_stdget_writecount,
143	.vop_add_writecount =	vop_stdadd_writecount,
144};
145
146/*
147 * Series of placeholder functions for various error returns for
148 * VOPs.
149 */
150
151int
152vop_eopnotsupp(struct vop_generic_args *ap)
153{
154	/*
155	printf("vop_notsupp[%s]\n", ap->a_desc->vdesc_name);
156	*/
157
158	return (EOPNOTSUPP);
159}
160
161int
162vop_ebadf(struct vop_generic_args *ap)
163{
164
165	return (EBADF);
166}
167
168int
169vop_enotty(struct vop_generic_args *ap)
170{
171
172	return (ENOTTY);
173}
174
175int
176vop_einval(struct vop_generic_args *ap)
177{
178
179	return (EINVAL);
180}
181
182int
183vop_enoent(struct vop_generic_args *ap)
184{
185
186	return (ENOENT);
187}
188
189int
190vop_null(struct vop_generic_args *ap)
191{
192
193	return (0);
194}
195
196/*
197 * Helper function to panic on some bad VOPs in some filesystems.
198 */
199int
200vop_panic(struct vop_generic_args *ap)
201{
202
203	panic("filesystem goof: vop_panic[%s]", ap->a_desc->vdesc_name);
204}
205
206/*
207 * vop_std<something> and vop_no<something> are default functions for use by
208 * filesystems that need the "default reasonable" implementation for a
209 * particular operation.
210 *
211 * The documentation for the operations they implement exists (if it exists)
212 * in the VOP_<SOMETHING>(9) manpage (all uppercase).
213 */
214
215/*
216 * Default vop for filesystems that do not support name lookup
217 */
218static int
219vop_nolookup(ap)
220	struct vop_lookup_args /* {
221		struct vnode *a_dvp;
222		struct vnode **a_vpp;
223		struct componentname *a_cnp;
224	} */ *ap;
225{
226
227	*ap->a_vpp = NULL;
228	return (ENOTDIR);
229}
230
231/*
232 * vop_norename:
233 *
234 * Handle unlock and reference counting for arguments of vop_rename
235 * for filesystems that do not implement rename operation.
236 */
237static int
238vop_norename(struct vop_rename_args *ap)
239{
240
241	vop_rename_fail(ap);
242	return (EOPNOTSUPP);
243}
244
245/*
246 *	vop_nostrategy:
247 *
248 *	Strategy routine for VFS devices that have none.
249 *
250 *	BIO_ERROR and B_INVAL must be cleared prior to calling any strategy
251 *	routine.  Typically this is done for a BIO_READ strategy call.
252 *	Typically B_INVAL is assumed to already be clear prior to a write
253 *	and should not be cleared manually unless you just made the buffer
254 *	invalid.  BIO_ERROR should be cleared either way.
255 */
256
257static int
258vop_nostrategy (struct vop_strategy_args *ap)
259{
260	printf("No strategy for buffer at %p\n", ap->a_bp);
261	vn_printf(ap->a_vp, "vnode ");
262	ap->a_bp->b_ioflags |= BIO_ERROR;
263	ap->a_bp->b_error = EOPNOTSUPP;
264	bufdone(ap->a_bp);
265	return (EOPNOTSUPP);
266}
267
268static int
269get_next_dirent(struct vnode *vp, struct dirent **dpp, char *dirbuf,
270		int dirbuflen, off_t *off, char **cpos, int *len,
271		int *eofflag, struct thread *td)
272{
273	int error, reclen;
274	struct uio uio;
275	struct iovec iov;
276	struct dirent *dp;
277
278	KASSERT(VOP_ISLOCKED(vp), ("vp %p is not locked", vp));
279	KASSERT(vp->v_type == VDIR, ("vp %p is not a directory", vp));
280
281	if (*len == 0) {
282		iov.iov_base = dirbuf;
283		iov.iov_len = dirbuflen;
284
285		uio.uio_iov = &iov;
286		uio.uio_iovcnt = 1;
287		uio.uio_offset = *off;
288		uio.uio_resid = dirbuflen;
289		uio.uio_segflg = UIO_SYSSPACE;
290		uio.uio_rw = UIO_READ;
291		uio.uio_td = td;
292
293		*eofflag = 0;
294
295#ifdef MAC
296		error = mac_vnode_check_readdir(td->td_ucred, vp);
297		if (error == 0)
298#endif
299			error = VOP_READDIR(vp, &uio, td->td_ucred, eofflag,
300		    		NULL, NULL);
301		if (error)
302			return (error);
303
304		*off = uio.uio_offset;
305
306		*cpos = dirbuf;
307		*len = (dirbuflen - uio.uio_resid);
308
309		if (*len == 0)
310			return (ENOENT);
311	}
312
313	dp = (struct dirent *)(*cpos);
314	reclen = dp->d_reclen;
315	*dpp = dp;
316
317	/* check for malformed directory.. */
318	if (reclen < DIRENT_MINSIZE)
319		return (EINVAL);
320
321	*cpos += reclen;
322	*len -= reclen;
323
324	return (0);
325}
326
327/*
328 * Check if a named file exists in a given directory vnode.
329 */
330static int
331dirent_exists(struct vnode *vp, const char *dirname, struct thread *td)
332{
333	char *dirbuf, *cpos;
334	int error, eofflag, dirbuflen, len, found;
335	off_t off;
336	struct dirent *dp;
337	struct vattr va;
338
339	KASSERT(VOP_ISLOCKED(vp), ("vp %p is not locked", vp));
340	KASSERT(vp->v_type == VDIR, ("vp %p is not a directory", vp));
341
342	found = 0;
343
344	error = VOP_GETATTR(vp, &va, td->td_ucred);
345	if (error)
346		return (found);
347
348	dirbuflen = DEV_BSIZE;
349	if (dirbuflen < va.va_blocksize)
350		dirbuflen = va.va_blocksize;
351	dirbuf = (char *)malloc(dirbuflen, M_TEMP, M_WAITOK);
352
353	off = 0;
354	len = 0;
355	do {
356		error = get_next_dirent(vp, &dp, dirbuf, dirbuflen, &off,
357					&cpos, &len, &eofflag, td);
358		if (error)
359			goto out;
360
361		if (dp->d_type != DT_WHT && dp->d_fileno != 0 &&
362		    strcmp(dp->d_name, dirname) == 0) {
363			found = 1;
364			goto out;
365		}
366	} while (len > 0 || !eofflag);
367
368out:
369	free(dirbuf, M_TEMP);
370	return (found);
371}
372
373int
374vop_stdaccess(struct vop_access_args *ap)
375{
376
377	KASSERT((ap->a_accmode & ~(VEXEC | VWRITE | VREAD | VADMIN |
378	    VAPPEND)) == 0, ("invalid bit in accmode"));
379
380	return (VOP_ACCESSX(ap->a_vp, ap->a_accmode, ap->a_cred, ap->a_td));
381}
382
383int
384vop_stdaccessx(struct vop_accessx_args *ap)
385{
386	int error;
387	accmode_t accmode = ap->a_accmode;
388
389	error = vfs_unixify_accmode(&accmode);
390	if (error != 0)
391		return (error);
392
393	if (accmode == 0)
394		return (0);
395
396	return (VOP_ACCESS(ap->a_vp, accmode, ap->a_cred, ap->a_td));
397}
398
399/*
400 * Advisory record locking support
401 */
402int
403vop_stdadvlock(struct vop_advlock_args *ap)
404{
405	struct vnode *vp;
406	struct vattr vattr;
407	int error;
408
409	vp = ap->a_vp;
410	if (ap->a_fl->l_whence == SEEK_END) {
411		/*
412		 * The NFSv4 server must avoid doing a vn_lock() here, since it
413		 * can deadlock the nfsd threads, due to a LOR.  Fortunately
414		 * the NFSv4 server always uses SEEK_SET and this code is
415		 * only required for the SEEK_END case.
416		 */
417		vn_lock(vp, LK_SHARED | LK_RETRY);
418		error = VOP_GETATTR(vp, &vattr, curthread->td_ucred);
419		VOP_UNLOCK(vp, 0);
420		if (error)
421			return (error);
422	} else
423		vattr.va_size = 0;
424
425	return (lf_advlock(ap, &(vp->v_lockf), vattr.va_size));
426}
427
428int
429vop_stdadvlockasync(struct vop_advlockasync_args *ap)
430{
431	struct vnode *vp;
432	struct vattr vattr;
433	int error;
434
435	vp = ap->a_vp;
436	if (ap->a_fl->l_whence == SEEK_END) {
437		/* The size argument is only needed for SEEK_END. */
438		vn_lock(vp, LK_SHARED | LK_RETRY);
439		error = VOP_GETATTR(vp, &vattr, curthread->td_ucred);
440		VOP_UNLOCK(vp, 0);
441		if (error)
442			return (error);
443	} else
444		vattr.va_size = 0;
445
446	return (lf_advlockasync(ap, &(vp->v_lockf), vattr.va_size));
447}
448
449int
450vop_stdadvlockpurge(struct vop_advlockpurge_args *ap)
451{
452	struct vnode *vp;
453
454	vp = ap->a_vp;
455	lf_purgelocks(vp, &vp->v_lockf);
456	return (0);
457}
458
459/*
460 * vop_stdpathconf:
461 *
462 * Standard implementation of POSIX pathconf, to get information about limits
463 * for a filesystem.
464 * Override per filesystem for the case where the filesystem has smaller
465 * limits.
466 */
467int
468vop_stdpathconf(ap)
469	struct vop_pathconf_args /* {
470	struct vnode *a_vp;
471	int a_name;
472	int *a_retval;
473	} */ *ap;
474{
475
476	switch (ap->a_name) {
477		case _PC_ASYNC_IO:
478			*ap->a_retval = _POSIX_ASYNCHRONOUS_IO;
479			return (0);
480		case _PC_PATH_MAX:
481			*ap->a_retval = PATH_MAX;
482			return (0);
483		case _PC_ACL_EXTENDED:
484		case _PC_ACL_NFS4:
485		case _PC_CAP_PRESENT:
486		case _PC_INF_PRESENT:
487		case _PC_MAC_PRESENT:
488			*ap->a_retval = 0;
489			return (0);
490		default:
491			return (EINVAL);
492	}
493	/* NOTREACHED */
494}
495
496/*
497 * Standard lock, unlock and islocked functions.
498 */
499int
500vop_stdlock(ap)
501	struct vop_lock1_args /* {
502		struct vnode *a_vp;
503		int a_flags;
504		char *file;
505		int line;
506	} */ *ap;
507{
508	struct vnode *vp = ap->a_vp;
509	struct mtx *ilk;
510
511	ilk = VI_MTX(vp);
512	return (lockmgr_lock_fast_path(vp->v_vnlock, ap->a_flags,
513	    (ilk != NULL) ? &ilk->lock_object : NULL, ap->a_file, ap->a_line));
514}
515
516/* See above. */
517int
518vop_stdunlock(ap)
519	struct vop_unlock_args /* {
520		struct vnode *a_vp;
521		int a_flags;
522	} */ *ap;
523{
524	struct vnode *vp = ap->a_vp;
525	struct mtx *ilk;
526
527	ilk = VI_MTX(vp);
528	return (lockmgr_unlock_fast_path(vp->v_vnlock, ap->a_flags,
529	    (ilk != NULL) ? &ilk->lock_object : NULL));
530}
531
532/* See above. */
533int
534vop_stdislocked(ap)
535	struct vop_islocked_args /* {
536		struct vnode *a_vp;
537	} */ *ap;
538{
539
540	return (lockstatus(ap->a_vp->v_vnlock));
541}
542
543/*
544 * Return true for select/poll.
545 */
546int
547vop_nopoll(ap)
548	struct vop_poll_args /* {
549		struct vnode *a_vp;
550		int  a_events;
551		struct ucred *a_cred;
552		struct thread *a_td;
553	} */ *ap;
554{
555
556	return (poll_no_poll(ap->a_events));
557}
558
559/*
560 * Implement poll for local filesystems that support it.
561 */
562int
563vop_stdpoll(ap)
564	struct vop_poll_args /* {
565		struct vnode *a_vp;
566		int  a_events;
567		struct ucred *a_cred;
568		struct thread *a_td;
569	} */ *ap;
570{
571	if (ap->a_events & ~POLLSTANDARD)
572		return (vn_pollrecord(ap->a_vp, ap->a_td, ap->a_events));
573	return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
574}
575
576/*
577 * Return our mount point, as we will take charge of the writes.
578 */
579int
580vop_stdgetwritemount(ap)
581	struct vop_getwritemount_args /* {
582		struct vnode *a_vp;
583		struct mount **a_mpp;
584	} */ *ap;
585{
586	struct mount *mp;
587
588	/*
589	 * XXX Since this is called unlocked we may be recycled while
590	 * attempting to ref the mount.  If this is the case or mountpoint
591	 * will be set to NULL.  We only have to prevent this call from
592	 * returning with a ref to an incorrect mountpoint.  It is not
593	 * harmful to return with a ref to our previous mountpoint.
594	 */
595	mp = ap->a_vp->v_mount;
596	if (mp != NULL) {
597		vfs_ref(mp);
598		if (mp != ap->a_vp->v_mount) {
599			vfs_rel(mp);
600			mp = NULL;
601		}
602	}
603	*(ap->a_mpp) = mp;
604	return (0);
605}
606
607/*
608 * If the file system doesn't implement VOP_BMAP, then return sensible defaults:
609 * - Return the vnode's bufobj instead of any underlying device's bufobj
610 * - Calculate the physical block number as if there were equal size
611 *   consecutive blocks, but
612 * - Report no contiguous runs of blocks.
613 */
614int
615vop_stdbmap(ap)
616	struct vop_bmap_args /* {
617		struct vnode *a_vp;
618		daddr_t  a_bn;
619		struct bufobj **a_bop;
620		daddr_t *a_bnp;
621		int *a_runp;
622		int *a_runb;
623	} */ *ap;
624{
625
626	if (ap->a_bop != NULL)
627		*ap->a_bop = &ap->a_vp->v_bufobj;
628	if (ap->a_bnp != NULL)
629		*ap->a_bnp = ap->a_bn * btodb(ap->a_vp->v_mount->mnt_stat.f_iosize);
630	if (ap->a_runp != NULL)
631		*ap->a_runp = 0;
632	if (ap->a_runb != NULL)
633		*ap->a_runb = 0;
634	return (0);
635}
636
637int
638vop_stdfsync(ap)
639	struct vop_fsync_args /* {
640		struct vnode *a_vp;
641		int a_waitfor;
642		struct thread *a_td;
643	} */ *ap;
644{
645	struct vnode *vp;
646	struct buf *bp, *nbp;
647	struct bufobj *bo;
648	struct mount *mp;
649	int error, maxretry;
650
651	error = 0;
652	maxretry = 10000;     /* large, arbitrarily chosen */
653	vp = ap->a_vp;
654	mp = NULL;
655	if (vp->v_type == VCHR) {
656		VI_LOCK(vp);
657		mp = vp->v_rdev->si_mountpt;
658		VI_UNLOCK(vp);
659	}
660	bo = &vp->v_bufobj;
661	BO_LOCK(bo);
662loop1:
663	/*
664	 * MARK/SCAN initialization to avoid infinite loops.
665	 */
666        TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs) {
667                bp->b_vflags &= ~BV_SCANNED;
668		bp->b_error = 0;
669	}
670
671	/*
672	 * Flush all dirty buffers associated with a vnode.
673	 */
674loop2:
675	TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
676		if ((bp->b_vflags & BV_SCANNED) != 0)
677			continue;
678		bp->b_vflags |= BV_SCANNED;
679		if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
680			if (ap->a_waitfor != MNT_WAIT)
681				continue;
682			if (BUF_LOCK(bp,
683			    LK_EXCLUSIVE | LK_INTERLOCK | LK_SLEEPFAIL,
684			    BO_LOCKPTR(bo)) != 0) {
685				BO_LOCK(bo);
686				goto loop1;
687			}
688			BO_LOCK(bo);
689		}
690		BO_UNLOCK(bo);
691		KASSERT(bp->b_bufobj == bo,
692		    ("bp %p wrong b_bufobj %p should be %p",
693		    bp, bp->b_bufobj, bo));
694		if ((bp->b_flags & B_DELWRI) == 0)
695			panic("fsync: not dirty");
696		if ((vp->v_object != NULL) && (bp->b_flags & B_CLUSTEROK)) {
697			vfs_bio_awrite(bp);
698		} else {
699			bremfree(bp);
700			bawrite(bp);
701		}
702		if (maxretry < 1000)
703			pause("dirty", hz < 1000 ? 1 : hz / 1000);
704		BO_LOCK(bo);
705		goto loop2;
706	}
707
708	/*
709	 * If synchronous the caller expects us to completely resolve all
710	 * dirty buffers in the system.  Wait for in-progress I/O to
711	 * complete (which could include background bitmap writes), then
712	 * retry if dirty blocks still exist.
713	 */
714	if (ap->a_waitfor == MNT_WAIT) {
715		bufobj_wwait(bo, 0, 0);
716		if (bo->bo_dirty.bv_cnt > 0) {
717			/*
718			 * If we are unable to write any of these buffers
719			 * then we fail now rather than trying endlessly
720			 * to write them out.
721			 */
722			TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs)
723				if ((error = bp->b_error) == 0)
724					continue;
725			if ((mp != NULL && mp->mnt_secondary_writes > 0) ||
726			    (error == 0 && --maxretry >= 0))
727				goto loop1;
728			if (error == 0)
729				error = EAGAIN;
730		}
731	}
732	BO_UNLOCK(bo);
733	if (error != 0)
734		vn_printf(vp, "fsync: giving up on dirty (error = %d) ", error);
735
736	return (error);
737}
738
739static int
740vop_stdfdatasync(struct vop_fdatasync_args *ap)
741{
742
743	return (VOP_FSYNC(ap->a_vp, MNT_WAIT, ap->a_td));
744}
745
746int
747vop_stdfdatasync_buf(struct vop_fdatasync_args *ap)
748{
749	struct vop_fsync_args apf;
750
751	apf.a_vp = ap->a_vp;
752	apf.a_waitfor = MNT_WAIT;
753	apf.a_td = ap->a_td;
754	return (vop_stdfsync(&apf));
755}
756
757/* XXX Needs good comment and more info in the manpage (VOP_GETPAGES(9)). */
758int
759vop_stdgetpages(ap)
760	struct vop_getpages_args /* {
761		struct vnode *a_vp;
762		vm_page_t *a_m;
763		int a_count;
764		int *a_rbehind;
765		int *a_rahead;
766	} */ *ap;
767{
768
769	return vnode_pager_generic_getpages(ap->a_vp, ap->a_m,
770	    ap->a_count, ap->a_rbehind, ap->a_rahead, NULL, NULL);
771}
772
773static int
774vop_stdgetpages_async(struct vop_getpages_async_args *ap)
775{
776	int error;
777
778	error = VOP_GETPAGES(ap->a_vp, ap->a_m, ap->a_count, ap->a_rbehind,
779	    ap->a_rahead);
780	ap->a_iodone(ap->a_arg, ap->a_m, ap->a_count, error);
781	return (error);
782}
783
784int
785vop_stdkqfilter(struct vop_kqfilter_args *ap)
786{
787	return vfs_kqfilter(ap);
788}
789
790/* XXX Needs good comment and more info in the manpage (VOP_PUTPAGES(9)). */
791int
792vop_stdputpages(ap)
793	struct vop_putpages_args /* {
794		struct vnode *a_vp;
795		vm_page_t *a_m;
796		int a_count;
797		int a_sync;
798		int *a_rtvals;
799	} */ *ap;
800{
801
802	return vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count,
803	     ap->a_sync, ap->a_rtvals);
804}
805
806int
807vop_stdvptofh(struct vop_vptofh_args *ap)
808{
809	return (EOPNOTSUPP);
810}
811
812int
813vop_stdvptocnp(struct vop_vptocnp_args *ap)
814{
815	struct vnode *vp = ap->a_vp;
816	struct vnode **dvp = ap->a_vpp;
817	struct ucred *cred = ap->a_cred;
818	char *buf = ap->a_buf;
819	int *buflen = ap->a_buflen;
820	char *dirbuf, *cpos;
821	int i, error, eofflag, dirbuflen, flags, locked, len, covered;
822	off_t off;
823	ino_t fileno;
824	struct vattr va;
825	struct nameidata nd;
826	struct thread *td;
827	struct dirent *dp;
828	struct vnode *mvp;
829
830	i = *buflen;
831	error = 0;
832	covered = 0;
833	td = curthread;
834
835	if (vp->v_type != VDIR)
836		return (ENOENT);
837
838	error = VOP_GETATTR(vp, &va, cred);
839	if (error)
840		return (error);
841
842	VREF(vp);
843	locked = VOP_ISLOCKED(vp);
844	VOP_UNLOCK(vp, 0);
845	NDINIT_ATVP(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF, UIO_SYSSPACE,
846	    "..", vp, td);
847	flags = FREAD;
848	error = vn_open_cred(&nd, &flags, 0, VN_OPEN_NOAUDIT, cred, NULL);
849	if (error) {
850		vn_lock(vp, locked | LK_RETRY);
851		return (error);
852	}
853	NDFREE(&nd, NDF_ONLY_PNBUF);
854
855	mvp = *dvp = nd.ni_vp;
856
857	if (vp->v_mount != (*dvp)->v_mount &&
858	    ((*dvp)->v_vflag & VV_ROOT) &&
859	    ((*dvp)->v_mount->mnt_flag & MNT_UNION)) {
860		*dvp = (*dvp)->v_mount->mnt_vnodecovered;
861		VREF(mvp);
862		VOP_UNLOCK(mvp, 0);
863		vn_close(mvp, FREAD, cred, td);
864		VREF(*dvp);
865		vn_lock(*dvp, LK_SHARED | LK_RETRY);
866		covered = 1;
867	}
868
869	fileno = va.va_fileid;
870
871	dirbuflen = DEV_BSIZE;
872	if (dirbuflen < va.va_blocksize)
873		dirbuflen = va.va_blocksize;
874	dirbuf = (char *)malloc(dirbuflen, M_TEMP, M_WAITOK);
875
876	if ((*dvp)->v_type != VDIR) {
877		error = ENOENT;
878		goto out;
879	}
880
881	off = 0;
882	len = 0;
883	do {
884		/* call VOP_READDIR of parent */
885		error = get_next_dirent(*dvp, &dp, dirbuf, dirbuflen, &off,
886					&cpos, &len, &eofflag, td);
887		if (error)
888			goto out;
889
890		if ((dp->d_type != DT_WHT) &&
891		    (dp->d_fileno == fileno)) {
892			if (covered) {
893				VOP_UNLOCK(*dvp, 0);
894				vn_lock(mvp, LK_SHARED | LK_RETRY);
895				if (dirent_exists(mvp, dp->d_name, td)) {
896					error = ENOENT;
897					VOP_UNLOCK(mvp, 0);
898					vn_lock(*dvp, LK_SHARED | LK_RETRY);
899					goto out;
900				}
901				VOP_UNLOCK(mvp, 0);
902				vn_lock(*dvp, LK_SHARED | LK_RETRY);
903			}
904			i -= dp->d_namlen;
905
906			if (i < 0) {
907				error = ENOMEM;
908				goto out;
909			}
910			if (dp->d_namlen == 1 && dp->d_name[0] == '.') {
911				error = ENOENT;
912			} else {
913				bcopy(dp->d_name, buf + i, dp->d_namlen);
914				error = 0;
915			}
916			goto out;
917		}
918	} while (len > 0 || !eofflag);
919	error = ENOENT;
920
921out:
922	free(dirbuf, M_TEMP);
923	if (!error) {
924		*buflen = i;
925		vref(*dvp);
926	}
927	if (covered) {
928		vput(*dvp);
929		vrele(mvp);
930	} else {
931		VOP_UNLOCK(mvp, 0);
932		vn_close(mvp, FREAD, cred, td);
933	}
934	vn_lock(vp, locked | LK_RETRY);
935	return (error);
936}
937
938int
939vop_stdallocate(struct vop_allocate_args *ap)
940{
941#ifdef __notyet__
942	struct statfs *sfs;
943	off_t maxfilesize = 0;
944#endif
945	struct iovec aiov;
946	struct vattr vattr, *vap;
947	struct uio auio;
948	off_t fsize, len, cur, offset;
949	uint8_t *buf;
950	struct thread *td;
951	struct vnode *vp;
952	size_t iosize;
953	int error;
954
955	buf = NULL;
956	error = 0;
957	td = curthread;
958	vap = &vattr;
959	vp = ap->a_vp;
960	len = *ap->a_len;
961	offset = *ap->a_offset;
962
963	error = VOP_GETATTR(vp, vap, td->td_ucred);
964	if (error != 0)
965		goto out;
966	fsize = vap->va_size;
967	iosize = vap->va_blocksize;
968	if (iosize == 0)
969		iosize = BLKDEV_IOSIZE;
970	if (iosize > MAXPHYS)
971		iosize = MAXPHYS;
972	buf = malloc(iosize, M_TEMP, M_WAITOK);
973
974#ifdef __notyet__
975	/*
976	 * Check if the filesystem sets f_maxfilesize; if not use
977	 * VOP_SETATTR to perform the check.
978	 */
979	sfs = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
980	error = VFS_STATFS(vp->v_mount, sfs, td);
981	if (error == 0)
982		maxfilesize = sfs->f_maxfilesize;
983	free(sfs, M_STATFS);
984	if (error != 0)
985		goto out;
986	if (maxfilesize) {
987		if (offset > maxfilesize || len > maxfilesize ||
988		    offset + len > maxfilesize) {
989			error = EFBIG;
990			goto out;
991		}
992	} else
993#endif
994	if (offset + len > vap->va_size) {
995		/*
996		 * Test offset + len against the filesystem's maxfilesize.
997		 */
998		VATTR_NULL(vap);
999		vap->va_size = offset + len;
1000		error = VOP_SETATTR(vp, vap, td->td_ucred);
1001		if (error != 0)
1002			goto out;
1003		VATTR_NULL(vap);
1004		vap->va_size = fsize;
1005		error = VOP_SETATTR(vp, vap, td->td_ucred);
1006		if (error != 0)
1007			goto out;
1008	}
1009
1010	for (;;) {
1011		/*
1012		 * Read and write back anything below the nominal file
1013		 * size.  There's currently no way outside the filesystem
1014		 * to know whether this area is sparse or not.
1015		 */
1016		cur = iosize;
1017		if ((offset % iosize) != 0)
1018			cur -= (offset % iosize);
1019		if (cur > len)
1020			cur = len;
1021		if (offset < fsize) {
1022			aiov.iov_base = buf;
1023			aiov.iov_len = cur;
1024			auio.uio_iov = &aiov;
1025			auio.uio_iovcnt = 1;
1026			auio.uio_offset = offset;
1027			auio.uio_resid = cur;
1028			auio.uio_segflg = UIO_SYSSPACE;
1029			auio.uio_rw = UIO_READ;
1030			auio.uio_td = td;
1031			error = VOP_READ(vp, &auio, 0, td->td_ucred);
1032			if (error != 0)
1033				break;
1034			if (auio.uio_resid > 0) {
1035				bzero(buf + cur - auio.uio_resid,
1036				    auio.uio_resid);
1037			}
1038		} else {
1039			bzero(buf, cur);
1040		}
1041
1042		aiov.iov_base = buf;
1043		aiov.iov_len = cur;
1044		auio.uio_iov = &aiov;
1045		auio.uio_iovcnt = 1;
1046		auio.uio_offset = offset;
1047		auio.uio_resid = cur;
1048		auio.uio_segflg = UIO_SYSSPACE;
1049		auio.uio_rw = UIO_WRITE;
1050		auio.uio_td = td;
1051
1052		error = VOP_WRITE(vp, &auio, 0, td->td_ucred);
1053		if (error != 0)
1054			break;
1055
1056		len -= cur;
1057		offset += cur;
1058		if (len == 0)
1059			break;
1060		if (should_yield())
1061			break;
1062	}
1063
1064 out:
1065	*ap->a_len = len;
1066	*ap->a_offset = offset;
1067	free(buf, M_TEMP);
1068	return (error);
1069}
1070
1071int
1072vop_stdadvise(struct vop_advise_args *ap)
1073{
1074	struct vnode *vp;
1075	struct bufobj *bo;
1076	daddr_t startn, endn;
1077	off_t start, end;
1078	int bsize, error;
1079
1080	vp = ap->a_vp;
1081	switch (ap->a_advice) {
1082	case POSIX_FADV_WILLNEED:
1083		/*
1084		 * Do nothing for now.  Filesystems should provide a
1085		 * custom method which starts an asynchronous read of
1086		 * the requested region.
1087		 */
1088		error = 0;
1089		break;
1090	case POSIX_FADV_DONTNEED:
1091		error = 0;
1092		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1093		if (vp->v_iflag & VI_DOOMED) {
1094			VOP_UNLOCK(vp, 0);
1095			break;
1096		}
1097
1098		/*
1099		 * Deactivate pages in the specified range from the backing VM
1100		 * object.  Pages that are resident in the buffer cache will
1101		 * remain wired until their corresponding buffers are released
1102		 * below.
1103		 */
1104		if (vp->v_object != NULL) {
1105			start = trunc_page(ap->a_start);
1106			end = round_page(ap->a_end);
1107			VM_OBJECT_RLOCK(vp->v_object);
1108			vm_object_page_noreuse(vp->v_object, OFF_TO_IDX(start),
1109			    OFF_TO_IDX(end));
1110			VM_OBJECT_RUNLOCK(vp->v_object);
1111		}
1112
1113		bo = &vp->v_bufobj;
1114		BO_RLOCK(bo);
1115		bsize = vp->v_bufobj.bo_bsize;
1116		startn = ap->a_start / bsize;
1117		endn = ap->a_end / bsize;
1118		error = bnoreuselist(&bo->bo_clean, bo, startn, endn);
1119		if (error == 0)
1120			error = bnoreuselist(&bo->bo_dirty, bo, startn, endn);
1121		BO_RUNLOCK(bo);
1122		VOP_UNLOCK(vp, 0);
1123		break;
1124	default:
1125		error = EINVAL;
1126		break;
1127	}
1128	return (error);
1129}
1130
1131int
1132vop_stdunp_bind(struct vop_unp_bind_args *ap)
1133{
1134
1135	ap->a_vp->v_socket = ap->a_socket;
1136	return (0);
1137}
1138
1139int
1140vop_stdunp_connect(struct vop_unp_connect_args *ap)
1141{
1142
1143	*ap->a_socket = ap->a_vp->v_socket;
1144	return (0);
1145}
1146
1147int
1148vop_stdunp_detach(struct vop_unp_detach_args *ap)
1149{
1150
1151	ap->a_vp->v_socket = NULL;
1152	return (0);
1153}
1154
1155static int
1156vop_stdis_text(struct vop_is_text_args *ap)
1157{
1158
1159	return ((ap->a_vp->v_vflag & VV_TEXT) != 0);
1160}
1161
1162static int
1163vop_stdset_text(struct vop_set_text_args *ap)
1164{
1165
1166	ap->a_vp->v_vflag |= VV_TEXT;
1167	return (0);
1168}
1169
1170static int
1171vop_stdunset_text(struct vop_unset_text_args *ap)
1172{
1173
1174	ap->a_vp->v_vflag &= ~VV_TEXT;
1175	return (0);
1176}
1177
1178static int
1179vop_stdget_writecount(struct vop_get_writecount_args *ap)
1180{
1181
1182	*ap->a_writecount = ap->a_vp->v_writecount;
1183	return (0);
1184}
1185
1186static int
1187vop_stdadd_writecount(struct vop_add_writecount_args *ap)
1188{
1189
1190	ap->a_vp->v_writecount += ap->a_inc;
1191	return (0);
1192}
1193
1194/*
1195 * vfs default ops
1196 * used to fill the vfs function table to get reasonable default return values.
1197 */
1198int
1199vfs_stdroot (mp, flags, vpp)
1200	struct mount *mp;
1201	int flags;
1202	struct vnode **vpp;
1203{
1204
1205	return (EOPNOTSUPP);
1206}
1207
1208int
1209vfs_stdstatfs (mp, sbp)
1210	struct mount *mp;
1211	struct statfs *sbp;
1212{
1213
1214	return (EOPNOTSUPP);
1215}
1216
1217int
1218vfs_stdquotactl (mp, cmds, uid, arg)
1219	struct mount *mp;
1220	int cmds;
1221	uid_t uid;
1222	void *arg;
1223{
1224
1225	return (EOPNOTSUPP);
1226}
1227
1228int
1229vfs_stdsync(mp, waitfor)
1230	struct mount *mp;
1231	int waitfor;
1232{
1233	struct vnode *vp, *mvp;
1234	struct thread *td;
1235	int error, lockreq, allerror = 0;
1236
1237	td = curthread;
1238	lockreq = LK_EXCLUSIVE | LK_INTERLOCK;
1239	if (waitfor != MNT_WAIT)
1240		lockreq |= LK_NOWAIT;
1241	/*
1242	 * Force stale buffer cache information to be flushed.
1243	 */
1244loop:
1245	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
1246		if (vp->v_bufobj.bo_dirty.bv_cnt == 0) {
1247			VI_UNLOCK(vp);
1248			continue;
1249		}
1250		if ((error = vget(vp, lockreq, td)) != 0) {
1251			if (error == ENOENT) {
1252				MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
1253				goto loop;
1254			}
1255			continue;
1256		}
1257		error = VOP_FSYNC(vp, waitfor, td);
1258		if (error)
1259			allerror = error;
1260		vput(vp);
1261	}
1262	return (allerror);
1263}
1264
1265int
1266vfs_stdnosync (mp, waitfor)
1267	struct mount *mp;
1268	int waitfor;
1269{
1270
1271	return (0);
1272}
1273
1274int
1275vfs_stdvget (mp, ino, flags, vpp)
1276	struct mount *mp;
1277	ino_t ino;
1278	int flags;
1279	struct vnode **vpp;
1280{
1281
1282	return (EOPNOTSUPP);
1283}
1284
1285int
1286vfs_stdfhtovp (mp, fhp, flags, vpp)
1287	struct mount *mp;
1288	struct fid *fhp;
1289	int flags;
1290	struct vnode **vpp;
1291{
1292
1293	return (EOPNOTSUPP);
1294}
1295
1296int
1297vfs_stdinit (vfsp)
1298	struct vfsconf *vfsp;
1299{
1300
1301	return (0);
1302}
1303
1304int
1305vfs_stduninit (vfsp)
1306	struct vfsconf *vfsp;
1307{
1308
1309	return(0);
1310}
1311
1312int
1313vfs_stdextattrctl(mp, cmd, filename_vp, attrnamespace, attrname)
1314	struct mount *mp;
1315	int cmd;
1316	struct vnode *filename_vp;
1317	int attrnamespace;
1318	const char *attrname;
1319{
1320
1321	if (filename_vp != NULL)
1322		VOP_UNLOCK(filename_vp, 0);
1323	return (EOPNOTSUPP);
1324}
1325
1326int
1327vfs_stdsysctl(mp, op, req)
1328	struct mount *mp;
1329	fsctlop_t op;
1330	struct sysctl_req *req;
1331{
1332
1333	return (EOPNOTSUPP);
1334}
1335
1336/* end of vfs default ops */
1337