1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2000-2004
5 *	Poul-Henning Kamp.  All rights reserved.
6 * Copyright (c) 1989, 1992-1993, 1995
7 *	The Regents of the University of California.  All rights reserved.
8 *
9 * This code is derived from software donated to Berkeley by
10 * Jan-Simon Pendry.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	@(#)kernfs_vnops.c	8.15 (Berkeley) 5/21/95
34 * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vnops.c 1.43
35 *
36 * $FreeBSD$
37 */
38
39/*
40 * TODO:
41 *	mkdir: want it ?
42 */
43
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/conf.h>
47#include <sys/dirent.h>
48#include <sys/eventhandler.h>
49#include <sys/fcntl.h>
50#include <sys/file.h>
51#include <sys/filedesc.h>
52#include <sys/filio.h>
53#include <sys/jail.h>
54#include <sys/kernel.h>
55#include <sys/limits.h>
56#include <sys/lock.h>
57#include <sys/malloc.h>
58#include <sys/mman.h>
59#include <sys/mount.h>
60#include <sys/namei.h>
61#include <sys/priv.h>
62#include <sys/proc.h>
63#include <sys/stat.h>
64#include <sys/sx.h>
65#include <sys/sysctl.h>
66#include <sys/time.h>
67#include <sys/ttycom.h>
68#include <sys/unistd.h>
69#include <sys/vnode.h>
70
71static struct vop_vector devfs_vnodeops;
72static struct vop_vector devfs_specops;
73static struct fileops devfs_ops_f;
74
75#include <fs/devfs/devfs.h>
76#include <fs/devfs/devfs_int.h>
77
78#include <security/mac/mac_framework.h>
79
80#include <vm/vm.h>
81#include <vm/vm_extern.h>
82#include <vm/vm_object.h>
83
84static MALLOC_DEFINE(M_CDEVPDATA, "DEVFSP", "Metainfo for cdev-fp data");
85
86struct mtx	devfs_de_interlock;
87MTX_SYSINIT(devfs_de_interlock, &devfs_de_interlock, "devfs interlock", MTX_DEF);
88struct sx	clone_drain_lock;
89SX_SYSINIT(clone_drain_lock, &clone_drain_lock, "clone events drain lock");
90struct mtx	cdevpriv_mtx;
91MTX_SYSINIT(cdevpriv_mtx, &cdevpriv_mtx, "cdevpriv lock", MTX_DEF);
92
93SYSCTL_DECL(_vfs_devfs);
94
95static int devfs_dotimes;
96SYSCTL_INT(_vfs_devfs, OID_AUTO, dotimes, CTLFLAG_RW,
97    &devfs_dotimes, 0, "Update timestamps on DEVFS with default precision");
98
99/*
100 * Update devfs node timestamp.  Note that updates are unlocked and
101 * stat(2) could see partially updated times.
102 */
103static void
104devfs_timestamp(struct timespec *tsp)
105{
106	time_t ts;
107
108	if (devfs_dotimes) {
109		vfs_timestamp(tsp);
110	} else {
111		ts = time_second;
112		if (tsp->tv_sec != ts) {
113			tsp->tv_sec = ts;
114			tsp->tv_nsec = 0;
115		}
116	}
117}
118
119static int
120devfs_fp_check(struct file *fp, struct cdev **devp, struct cdevsw **dswp,
121    int *ref)
122{
123
124	*dswp = devvn_refthread(fp->f_vnode, devp, ref);
125	if (*devp != fp->f_data) {
126		if (*dswp != NULL)
127			dev_relthread(*devp, *ref);
128		return (ENXIO);
129	}
130	KASSERT((*devp)->si_refcount > 0,
131	    ("devfs: un-referenced struct cdev *(%s)", devtoname(*devp)));
132	if (*dswp == NULL)
133		return (ENXIO);
134	curthread->td_fpop = fp;
135	return (0);
136}
137
138int
139devfs_get_cdevpriv(void **datap)
140{
141	struct file *fp;
142	struct cdev_privdata *p;
143	int error;
144
145	fp = curthread->td_fpop;
146	if (fp == NULL)
147		return (EBADF);
148	p = fp->f_cdevpriv;
149	if (p != NULL) {
150		error = 0;
151		*datap = p->cdpd_data;
152	} else
153		error = ENOENT;
154	return (error);
155}
156
157int
158devfs_set_cdevpriv(void *priv, d_priv_dtor_t *priv_dtr)
159{
160	struct file *fp;
161	struct cdev_priv *cdp;
162	struct cdev_privdata *p;
163	int error;
164
165	fp = curthread->td_fpop;
166	if (fp == NULL)
167		return (ENOENT);
168	cdp = cdev2priv((struct cdev *)fp->f_data);
169	p = malloc(sizeof(struct cdev_privdata), M_CDEVPDATA, M_WAITOK);
170	p->cdpd_data = priv;
171	p->cdpd_dtr = priv_dtr;
172	p->cdpd_fp = fp;
173	mtx_lock(&cdevpriv_mtx);
174	if (fp->f_cdevpriv == NULL) {
175		LIST_INSERT_HEAD(&cdp->cdp_fdpriv, p, cdpd_list);
176		fp->f_cdevpriv = p;
177		mtx_unlock(&cdevpriv_mtx);
178		error = 0;
179	} else {
180		mtx_unlock(&cdevpriv_mtx);
181		free(p, M_CDEVPDATA);
182		error = EBUSY;
183	}
184	return (error);
185}
186
187void
188devfs_destroy_cdevpriv(struct cdev_privdata *p)
189{
190
191	mtx_assert(&cdevpriv_mtx, MA_OWNED);
192	KASSERT(p->cdpd_fp->f_cdevpriv == p,
193	    ("devfs_destoy_cdevpriv %p != %p", p->cdpd_fp->f_cdevpriv, p));
194	p->cdpd_fp->f_cdevpriv = NULL;
195	LIST_REMOVE(p, cdpd_list);
196	mtx_unlock(&cdevpriv_mtx);
197	(p->cdpd_dtr)(p->cdpd_data);
198	free(p, M_CDEVPDATA);
199}
200
201static void
202devfs_fpdrop(struct file *fp)
203{
204	struct cdev_privdata *p;
205
206	mtx_lock(&cdevpriv_mtx);
207	if ((p = fp->f_cdevpriv) == NULL) {
208		mtx_unlock(&cdevpriv_mtx);
209		return;
210	}
211	devfs_destroy_cdevpriv(p);
212}
213
214void
215devfs_clear_cdevpriv(void)
216{
217	struct file *fp;
218
219	fp = curthread->td_fpop;
220	if (fp == NULL)
221		return;
222	devfs_fpdrop(fp);
223}
224
225static void
226devfs_usecount_add(struct vnode *vp)
227{
228	struct devfs_dirent *de;
229	struct cdev *dev;
230
231	mtx_lock(&devfs_de_interlock);
232	VI_LOCK(vp);
233	VNPASS(vp->v_type == VCHR || vp->v_type == VBAD, vp);
234	if (VN_IS_DOOMED(vp)) {
235		goto out_unlock;
236	}
237
238	de = vp->v_data;
239	dev = vp->v_rdev;
240	MPASS(de != NULL);
241	MPASS(dev != NULL);
242	dev->si_usecount++;
243	de->de_usecount++;
244out_unlock:
245	VI_UNLOCK(vp);
246	mtx_unlock(&devfs_de_interlock);
247}
248
249static void
250devfs_usecount_subl(struct vnode *vp)
251{
252	struct devfs_dirent *de;
253	struct cdev *dev;
254
255	mtx_assert(&devfs_de_interlock, MA_OWNED);
256	ASSERT_VI_LOCKED(vp, __func__);
257	VNPASS(vp->v_type == VCHR || vp->v_type == VBAD, vp);
258
259	de = vp->v_data;
260	dev = vp->v_rdev;
261	if (de == NULL)
262		return;
263	if (dev == NULL) {
264		MPASS(de->de_usecount == 0);
265		return;
266	}
267	if (dev->si_usecount < de->de_usecount)
268		panic("%s: si_usecount underflow for dev %p "
269		    "(has %ld, dirent has %d)\n",
270		    __func__, dev, dev->si_usecount, de->de_usecount);
271	if (VN_IS_DOOMED(vp)) {
272		dev->si_usecount -= de->de_usecount;
273		de->de_usecount = 0;
274	} else {
275		if (de->de_usecount == 0)
276			panic("%s: de_usecount underflow for dev %p\n",
277			    __func__, dev);
278		dev->si_usecount--;
279		de->de_usecount--;
280	}
281}
282
283static void
284devfs_usecount_sub(struct vnode *vp)
285{
286
287	mtx_lock(&devfs_de_interlock);
288	VI_LOCK(vp);
289	devfs_usecount_subl(vp);
290	VI_UNLOCK(vp);
291	mtx_unlock(&devfs_de_interlock);
292}
293
294static int
295devfs_usecountl(struct vnode *vp)
296{
297
298	VNPASS(vp->v_type == VCHR, vp);
299	mtx_assert(&devfs_de_interlock, MA_OWNED);
300	ASSERT_VI_LOCKED(vp, __func__);
301	return (vp->v_rdev->si_usecount);
302}
303
304int
305devfs_usecount(struct vnode *vp)
306{
307	int count;
308
309	VNPASS(vp->v_type == VCHR, vp);
310	mtx_lock(&devfs_de_interlock);
311	VI_LOCK(vp);
312	count = devfs_usecountl(vp);
313	VI_UNLOCK(vp);
314	mtx_unlock(&devfs_de_interlock);
315	return (count);
316}
317
318void
319devfs_ctty_ref(struct vnode *vp)
320{
321
322	vrefact(vp);
323	devfs_usecount_add(vp);
324}
325
326void
327devfs_ctty_unref(struct vnode *vp)
328{
329
330	devfs_usecount_sub(vp);
331	vrele(vp);
332}
333
334/*
335 * On success devfs_populate_vp() returns with dmp->dm_lock held.
336 */
337static int
338devfs_populate_vp(struct vnode *vp)
339{
340	struct devfs_dirent *de;
341	struct devfs_mount *dmp;
342	int locked;
343
344	ASSERT_VOP_LOCKED(vp, "devfs_populate_vp");
345
346	dmp = VFSTODEVFS(vp->v_mount);
347	if (!devfs_populate_needed(dmp)) {
348		sx_xlock(&dmp->dm_lock);
349		goto out_nopopulate;
350	}
351
352	locked = VOP_ISLOCKED(vp);
353
354	sx_xlock(&dmp->dm_lock);
355	DEVFS_DMP_HOLD(dmp);
356
357	/* Can't call devfs_populate() with the vnode lock held. */
358	VOP_UNLOCK(vp);
359	devfs_populate(dmp);
360
361	sx_xunlock(&dmp->dm_lock);
362	vn_lock(vp, locked | LK_RETRY);
363	sx_xlock(&dmp->dm_lock);
364	if (DEVFS_DMP_DROP(dmp)) {
365		sx_xunlock(&dmp->dm_lock);
366		devfs_unmount_final(dmp);
367		return (ERESTART);
368	}
369out_nopopulate:
370	if (VN_IS_DOOMED(vp)) {
371		sx_xunlock(&dmp->dm_lock);
372		return (ERESTART);
373	}
374	de = vp->v_data;
375	KASSERT(de != NULL,
376	    ("devfs_populate_vp: vp->v_data == NULL but vnode not doomed"));
377	if ((de->de_flags & DE_DOOMED) != 0) {
378		sx_xunlock(&dmp->dm_lock);
379		return (ERESTART);
380	}
381
382	return (0);
383}
384
385static int
386devfs_vptocnp(struct vop_vptocnp_args *ap)
387{
388	struct vnode *vp = ap->a_vp;
389	struct vnode **dvp = ap->a_vpp;
390	struct devfs_mount *dmp;
391	char *buf = ap->a_buf;
392	size_t *buflen = ap->a_buflen;
393	struct devfs_dirent *dd, *de;
394	int i, error;
395
396	dmp = VFSTODEVFS(vp->v_mount);
397
398	error = devfs_populate_vp(vp);
399	if (error != 0)
400		return (error);
401
402	if (vp->v_type != VCHR && vp->v_type != VDIR) {
403		error = ENOENT;
404		goto finished;
405	}
406
407	dd = vp->v_data;
408	if (vp->v_type == VDIR && dd == dmp->dm_rootdir) {
409		*dvp = vp;
410		vref(*dvp);
411		goto finished;
412	}
413
414	i = *buflen;
415	i -= dd->de_dirent->d_namlen;
416	if (i < 0) {
417		error = ENOMEM;
418		goto finished;
419	}
420	bcopy(dd->de_dirent->d_name, buf + i, dd->de_dirent->d_namlen);
421	*buflen = i;
422	de = devfs_parent_dirent(dd);
423	if (de == NULL) {
424		error = ENOENT;
425		goto finished;
426	}
427	mtx_lock(&devfs_de_interlock);
428	*dvp = de->de_vnode;
429	if (*dvp != NULL) {
430		VI_LOCK(*dvp);
431		mtx_unlock(&devfs_de_interlock);
432		vholdl(*dvp);
433		VI_UNLOCK(*dvp);
434		vref(*dvp);
435		vdrop(*dvp);
436	} else {
437		mtx_unlock(&devfs_de_interlock);
438		error = ENOENT;
439	}
440finished:
441	sx_xunlock(&dmp->dm_lock);
442	return (error);
443}
444
445/*
446 * Construct the fully qualified path name relative to the mountpoint.
447 * If a NULL cnp is provided, no '/' is appended to the resulting path.
448 */
449char *
450devfs_fqpn(char *buf, struct devfs_mount *dmp, struct devfs_dirent *dd,
451    struct componentname *cnp)
452{
453	int i;
454	struct devfs_dirent *de;
455
456	sx_assert(&dmp->dm_lock, SA_LOCKED);
457
458	i = SPECNAMELEN;
459	buf[i] = '\0';
460	if (cnp != NULL)
461		i -= cnp->cn_namelen;
462	if (i < 0)
463		 return (NULL);
464	if (cnp != NULL)
465		bcopy(cnp->cn_nameptr, buf + i, cnp->cn_namelen);
466	de = dd;
467	while (de != dmp->dm_rootdir) {
468		if (cnp != NULL || i < SPECNAMELEN) {
469			i--;
470			if (i < 0)
471				 return (NULL);
472			buf[i] = '/';
473		}
474		i -= de->de_dirent->d_namlen;
475		if (i < 0)
476			 return (NULL);
477		bcopy(de->de_dirent->d_name, buf + i,
478		    de->de_dirent->d_namlen);
479		de = devfs_parent_dirent(de);
480		if (de == NULL)
481			return (NULL);
482	}
483	return (buf + i);
484}
485
486static int
487devfs_allocv_drop_refs(int drop_dm_lock, struct devfs_mount *dmp,
488	struct devfs_dirent *de)
489{
490	int not_found;
491
492	not_found = 0;
493	if (de->de_flags & DE_DOOMED)
494		not_found = 1;
495	if (DEVFS_DE_DROP(de)) {
496		KASSERT(not_found == 1, ("DEVFS de dropped but not doomed"));
497		devfs_dirent_free(de);
498	}
499	if (DEVFS_DMP_DROP(dmp)) {
500		KASSERT(not_found == 1,
501			("DEVFS mount struct freed before dirent"));
502		not_found = 2;
503		sx_xunlock(&dmp->dm_lock);
504		devfs_unmount_final(dmp);
505	}
506	if (not_found == 1 || (drop_dm_lock && not_found != 2))
507		sx_unlock(&dmp->dm_lock);
508	return (not_found);
509}
510
511static void
512devfs_insmntque_dtr(struct vnode *vp, void *arg)
513{
514	struct devfs_dirent *de;
515
516	de = (struct devfs_dirent *)arg;
517	mtx_lock(&devfs_de_interlock);
518	vp->v_data = NULL;
519	de->de_vnode = NULL;
520	mtx_unlock(&devfs_de_interlock);
521	vgone(vp);
522	vput(vp);
523}
524
525/*
526 * devfs_allocv shall be entered with dmp->dm_lock held, and it drops
527 * it on return.
528 */
529int
530devfs_allocv(struct devfs_dirent *de, struct mount *mp, int lockmode,
531    struct vnode **vpp)
532{
533	int error;
534	struct vnode *vp;
535	struct cdev *dev;
536	struct devfs_mount *dmp;
537	struct cdevsw *dsw;
538	enum vgetstate vs;
539
540	dmp = VFSTODEVFS(mp);
541	if (de->de_flags & DE_DOOMED) {
542		sx_xunlock(&dmp->dm_lock);
543		return (ENOENT);
544	}
545loop:
546	DEVFS_DE_HOLD(de);
547	DEVFS_DMP_HOLD(dmp);
548	mtx_lock(&devfs_de_interlock);
549	vp = de->de_vnode;
550	if (vp != NULL) {
551		vs = vget_prep(vp);
552		mtx_unlock(&devfs_de_interlock);
553		sx_xunlock(&dmp->dm_lock);
554		vget_finish(vp, lockmode | LK_RETRY, vs);
555		sx_xlock(&dmp->dm_lock);
556		if (devfs_allocv_drop_refs(0, dmp, de)) {
557			vput(vp);
558			return (ENOENT);
559		}
560		else if (VN_IS_DOOMED(vp)) {
561			mtx_lock(&devfs_de_interlock);
562			if (de->de_vnode == vp) {
563				de->de_vnode = NULL;
564				vp->v_data = NULL;
565			}
566			mtx_unlock(&devfs_de_interlock);
567			vput(vp);
568			goto loop;
569		}
570		sx_xunlock(&dmp->dm_lock);
571		*vpp = vp;
572		return (0);
573	}
574	mtx_unlock(&devfs_de_interlock);
575	if (de->de_dirent->d_type == DT_CHR) {
576		if (!(de->de_cdp->cdp_flags & CDP_ACTIVE)) {
577			devfs_allocv_drop_refs(1, dmp, de);
578			return (ENOENT);
579		}
580		dev = &de->de_cdp->cdp_c;
581	} else {
582		dev = NULL;
583	}
584	error = getnewvnode("devfs", mp, &devfs_vnodeops, &vp);
585	if (error != 0) {
586		devfs_allocv_drop_refs(1, dmp, de);
587		printf("devfs_allocv: failed to allocate new vnode\n");
588		return (error);
589	}
590
591	if (de->de_dirent->d_type == DT_CHR) {
592		vp->v_type = VCHR;
593		VI_LOCK(vp);
594		dev_lock();
595		dev_refl(dev);
596		/* XXX: v_rdev should be protect by vnode lock */
597		vp->v_rdev = dev;
598		VNPASS(vp->v_usecount == 1, vp);
599		/* Special casing of ttys for deadfs.  Probably redundant. */
600		dsw = dev->si_devsw;
601		if (dsw != NULL && (dsw->d_flags & D_TTY) != 0)
602			vp->v_vflag |= VV_ISTTY;
603		dev_unlock();
604		VI_UNLOCK(vp);
605		if ((dev->si_flags & SI_ETERNAL) != 0)
606			vp->v_vflag |= VV_ETERNALDEV;
607		vp->v_op = &devfs_specops;
608	} else if (de->de_dirent->d_type == DT_DIR) {
609		vp->v_type = VDIR;
610	} else if (de->de_dirent->d_type == DT_LNK) {
611		vp->v_type = VLNK;
612	} else {
613		vp->v_type = VBAD;
614	}
615	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_NOWITNESS);
616	VN_LOCK_ASHARE(vp);
617	mtx_lock(&devfs_de_interlock);
618	vp->v_data = de;
619	de->de_vnode = vp;
620	mtx_unlock(&devfs_de_interlock);
621	error = insmntque1(vp, mp, devfs_insmntque_dtr, de);
622	if (error != 0) {
623		(void) devfs_allocv_drop_refs(1, dmp, de);
624		return (error);
625	}
626	if (devfs_allocv_drop_refs(0, dmp, de)) {
627		vput(vp);
628		return (ENOENT);
629	}
630#ifdef MAC
631	mac_devfs_vnode_associate(mp, de, vp);
632#endif
633	sx_xunlock(&dmp->dm_lock);
634	*vpp = vp;
635	return (0);
636}
637
638static int
639devfs_access(struct vop_access_args *ap)
640{
641	struct vnode *vp = ap->a_vp;
642	struct devfs_dirent *de;
643	struct proc *p;
644	int error;
645
646	de = vp->v_data;
647	if (vp->v_type == VDIR)
648		de = de->de_dir;
649
650	error = vaccess(vp->v_type, de->de_mode, de->de_uid, de->de_gid,
651	    ap->a_accmode, ap->a_cred);
652	if (error == 0)
653		return (0);
654	if (error != EACCES)
655		return (error);
656	p = ap->a_td->td_proc;
657	/* We do, however, allow access to the controlling terminal */
658	PROC_LOCK(p);
659	if (!(p->p_flag & P_CONTROLT)) {
660		PROC_UNLOCK(p);
661		return (error);
662	}
663	if (p->p_session->s_ttydp == de->de_cdp)
664		error = 0;
665	PROC_UNLOCK(p);
666	return (error);
667}
668
669_Static_assert(((FMASK | FCNTLFLAGS) & (FLASTCLOSE | FREVOKE)) == 0,
670    "devfs-only flag reuse failed");
671
672static int
673devfs_close(struct vop_close_args *ap)
674{
675	struct vnode *vp = ap->a_vp, *oldvp;
676	struct thread *td = ap->a_td;
677	struct proc *p;
678	struct cdev *dev = vp->v_rdev;
679	struct cdevsw *dsw;
680	struct devfs_dirent *de = vp->v_data;
681	int dflags, error, ref, vp_locked;
682
683	/*
684	 * XXX: Don't call d_close() if we were called because of
685	 * XXX: insmntque1() failure.
686	 */
687	if (vp->v_data == NULL)
688		return (0);
689
690	/*
691	 * Hack: a tty device that is a controlling terminal
692	 * has a reference from the session structure.
693	 * We cannot easily tell that a character device is
694	 * a controlling terminal, unless it is the closing
695	 * process' controlling terminal.  In that case,
696	 * if the reference count is 2 (this last descriptor
697	 * plus the session), release the reference from the session.
698	 */
699	if (de->de_usecount == 2 && td != NULL) {
700		p = td->td_proc;
701		PROC_LOCK(p);
702		if (vp == p->p_session->s_ttyvp) {
703			PROC_UNLOCK(p);
704			oldvp = NULL;
705			sx_xlock(&proctree_lock);
706			if (vp == p->p_session->s_ttyvp) {
707				SESS_LOCK(p->p_session);
708				mtx_lock(&devfs_de_interlock);
709				VI_LOCK(vp);
710				if (devfs_usecountl(vp) == 2 && !VN_IS_DOOMED(vp)) {
711					p->p_session->s_ttyvp = NULL;
712					p->p_session->s_ttydp = NULL;
713					oldvp = vp;
714				}
715				VI_UNLOCK(vp);
716				mtx_unlock(&devfs_de_interlock);
717				SESS_UNLOCK(p->p_session);
718			}
719			sx_xunlock(&proctree_lock);
720			if (oldvp != NULL)
721				devfs_ctty_unref(oldvp);
722		} else
723			PROC_UNLOCK(p);
724	}
725	/*
726	 * We do not want to really close the device if it
727	 * is still in use unless we are trying to close it
728	 * forcibly. Since every use (buffer, vnode, swap, cmap)
729	 * holds a reference to the vnode, and because we mark
730	 * any other vnodes that alias this device, when the
731	 * sum of the reference counts on all the aliased
732	 * vnodes descends to one, we are on last close.
733	 */
734	dsw = dev_refthread(dev, &ref);
735	if (dsw == NULL)
736		return (ENXIO);
737	dflags = 0;
738	mtx_lock(&devfs_de_interlock);
739	VI_LOCK(vp);
740	if (devfs_usecountl(vp) == 1)
741		dflags |= FLASTCLOSE;
742	devfs_usecount_subl(vp);
743	mtx_unlock(&devfs_de_interlock);
744	if (VN_IS_DOOMED(vp)) {
745		/* Forced close. */
746		dflags |= FREVOKE | FNONBLOCK;
747	} else if (dsw->d_flags & D_TRACKCLOSE) {
748		/* Keep device updated on status. */
749	} else if ((dflags & FLASTCLOSE) == 0) {
750		VI_UNLOCK(vp);
751		dev_relthread(dev, ref);
752		return (0);
753	}
754	vholdnz(vp);
755	VI_UNLOCK(vp);
756	vp_locked = VOP_ISLOCKED(vp);
757	VOP_UNLOCK(vp);
758	KASSERT(dev->si_refcount > 0,
759	    ("devfs_close() on un-referenced struct cdev *(%s)", devtoname(dev)));
760	error = dsw->d_close(dev, ap->a_fflag | dflags, S_IFCHR, td);
761	dev_relthread(dev, ref);
762	vn_lock(vp, vp_locked | LK_RETRY);
763	vdrop(vp);
764	return (error);
765}
766
767static int
768devfs_close_f(struct file *fp, struct thread *td)
769{
770	int error;
771	struct file *fpop;
772
773	/*
774	 * NB: td may be NULL if this descriptor is closed due to
775	 * garbage collection from a closed UNIX domain socket.
776	 */
777	fpop = curthread->td_fpop;
778	curthread->td_fpop = fp;
779	error = vnops.fo_close(fp, td);
780	curthread->td_fpop = fpop;
781
782	/*
783	 * The f_cdevpriv cannot be assigned non-NULL value while we
784	 * are destroying the file.
785	 */
786	if (fp->f_cdevpriv != NULL)
787		devfs_fpdrop(fp);
788	return (error);
789}
790
791static int
792devfs_getattr(struct vop_getattr_args *ap)
793{
794	struct vnode *vp = ap->a_vp;
795	struct vattr *vap = ap->a_vap;
796	struct devfs_dirent *de;
797	struct devfs_mount *dmp;
798	struct cdev *dev;
799	struct timeval boottime;
800	int error;
801
802	error = devfs_populate_vp(vp);
803	if (error != 0)
804		return (error);
805
806	dmp = VFSTODEVFS(vp->v_mount);
807	sx_xunlock(&dmp->dm_lock);
808
809	de = vp->v_data;
810	KASSERT(de != NULL, ("Null dirent in devfs_getattr vp=%p", vp));
811	if (vp->v_type == VDIR) {
812		de = de->de_dir;
813		KASSERT(de != NULL,
814		    ("Null dir dirent in devfs_getattr vp=%p", vp));
815	}
816	vap->va_uid = de->de_uid;
817	vap->va_gid = de->de_gid;
818	vap->va_mode = de->de_mode;
819	if (vp->v_type == VLNK)
820		vap->va_size = strlen(de->de_symlink);
821	else if (vp->v_type == VDIR)
822		vap->va_size = vap->va_bytes = DEV_BSIZE;
823	else
824		vap->va_size = 0;
825	if (vp->v_type != VDIR)
826		vap->va_bytes = 0;
827	vap->va_blocksize = DEV_BSIZE;
828	vap->va_type = vp->v_type;
829
830	getboottime(&boottime);
831#define fix(aa)							\
832	do {							\
833		if ((aa).tv_sec <= 3600) {			\
834			(aa).tv_sec = boottime.tv_sec;		\
835			(aa).tv_nsec = boottime.tv_usec * 1000; \
836		}						\
837	} while (0)
838
839	if (vp->v_type != VCHR)  {
840		fix(de->de_atime);
841		vap->va_atime = de->de_atime;
842		fix(de->de_mtime);
843		vap->va_mtime = de->de_mtime;
844		fix(de->de_ctime);
845		vap->va_ctime = de->de_ctime;
846	} else {
847		dev = vp->v_rdev;
848		fix(dev->si_atime);
849		vap->va_atime = dev->si_atime;
850		fix(dev->si_mtime);
851		vap->va_mtime = dev->si_mtime;
852		fix(dev->si_ctime);
853		vap->va_ctime = dev->si_ctime;
854
855		vap->va_rdev = cdev2priv(dev)->cdp_inode;
856	}
857	vap->va_gen = 0;
858	vap->va_flags = 0;
859	vap->va_filerev = 0;
860	vap->va_nlink = de->de_links;
861	vap->va_fileid = de->de_inode;
862
863	return (error);
864}
865
866/* ARGSUSED */
867static int
868devfs_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred, struct thread *td)
869{
870	struct file *fpop;
871	int error;
872
873	fpop = td->td_fpop;
874	td->td_fpop = fp;
875	error = vnops.fo_ioctl(fp, com, data, cred, td);
876	td->td_fpop = fpop;
877	return (error);
878}
879
880void *
881fiodgname_buf_get_ptr(void *fgnp, u_long com)
882{
883	union {
884		struct fiodgname_arg	fgn;
885#ifdef COMPAT_FREEBSD32
886		struct fiodgname_arg32	fgn32;
887#endif
888	} *fgnup;
889
890	fgnup = fgnp;
891	switch (com) {
892	case FIODGNAME:
893		return (fgnup->fgn.buf);
894#ifdef COMPAT_FREEBSD32
895	case FIODGNAME_32:
896		return ((void *)(uintptr_t)fgnup->fgn32.buf);
897#endif
898	default:
899		panic("Unhandled ioctl command %ld", com);
900	}
901}
902
903static int
904devfs_ioctl(struct vop_ioctl_args *ap)
905{
906	struct fiodgname_arg *fgn;
907	struct vnode *vpold, *vp;
908	struct cdevsw *dsw;
909	struct thread *td;
910	struct session *sess;
911	struct cdev *dev;
912	int error, ref, i;
913	const char *p;
914	u_long com;
915
916	vp = ap->a_vp;
917	com = ap->a_command;
918	td = ap->a_td;
919
920	dsw = devvn_refthread(vp, &dev, &ref);
921	if (dsw == NULL)
922		return (ENXIO);
923	KASSERT(dev->si_refcount > 0,
924	    ("devfs: un-referenced struct cdev *(%s)", devtoname(dev)));
925
926	switch (com) {
927	case FIODTYPE:
928		*(int *)ap->a_data = dsw->d_flags & D_TYPEMASK;
929		error = 0;
930		break;
931	case FIODGNAME:
932#ifdef	COMPAT_FREEBSD32
933	case FIODGNAME_32:
934#endif
935		fgn = ap->a_data;
936		p = devtoname(dev);
937		i = strlen(p) + 1;
938		if (i > fgn->len)
939			error = EINVAL;
940		else
941			error = copyout(p, fiodgname_buf_get_ptr(fgn, com), i);
942		break;
943	default:
944		error = dsw->d_ioctl(dev, com, ap->a_data, ap->a_fflag, td);
945	}
946
947	dev_relthread(dev, ref);
948	if (error == ENOIOCTL)
949		error = ENOTTY;
950
951	if (error == 0 && com == TIOCSCTTY) {
952		/*
953		 * Do nothing if reassigning same control tty, or if the
954		 * control tty has already disappeared.  If it disappeared,
955		 * it's because we were racing with TIOCNOTTY.  TIOCNOTTY
956		 * already took care of releasing the old vnode and we have
957		 * nothing left to do.
958		 */
959		sx_slock(&proctree_lock);
960		sess = td->td_proc->p_session;
961		if (sess->s_ttyvp == vp || sess->s_ttyp == NULL) {
962			sx_sunlock(&proctree_lock);
963			return (0);
964		}
965
966		devfs_ctty_ref(vp);
967		SESS_LOCK(sess);
968		vpold = sess->s_ttyvp;
969		sess->s_ttyvp = vp;
970		sess->s_ttydp = cdev2priv(dev);
971		SESS_UNLOCK(sess);
972
973		sx_sunlock(&proctree_lock);
974
975		/* Get rid of reference to old control tty */
976		if (vpold)
977			devfs_ctty_unref(vpold);
978	}
979	return (error);
980}
981
982/* ARGSUSED */
983static int
984devfs_kqfilter_f(struct file *fp, struct knote *kn)
985{
986	struct cdev *dev;
987	struct cdevsw *dsw;
988	int error, ref;
989	struct file *fpop;
990	struct thread *td;
991
992	td = curthread;
993	fpop = td->td_fpop;
994	error = devfs_fp_check(fp, &dev, &dsw, &ref);
995	if (error)
996		return (error);
997	error = dsw->d_kqfilter(dev, kn);
998	td->td_fpop = fpop;
999	dev_relthread(dev, ref);
1000	return (error);
1001}
1002
1003static inline int
1004devfs_prison_check(struct devfs_dirent *de, struct thread *td)
1005{
1006	struct cdev_priv *cdp;
1007	struct ucred *dcr;
1008	struct proc *p;
1009	int error;
1010
1011	cdp = de->de_cdp;
1012	if (cdp == NULL)
1013		return (0);
1014	dcr = cdp->cdp_c.si_cred;
1015	if (dcr == NULL)
1016		return (0);
1017
1018	error = prison_check(td->td_ucred, dcr);
1019	if (error == 0)
1020		return (0);
1021	/* We do, however, allow access to the controlling terminal */
1022	p = td->td_proc;
1023	PROC_LOCK(p);
1024	if (!(p->p_flag & P_CONTROLT)) {
1025		PROC_UNLOCK(p);
1026		return (error);
1027	}
1028	if (p->p_session->s_ttydp == cdp)
1029		error = 0;
1030	PROC_UNLOCK(p);
1031	return (error);
1032}
1033
1034static int
1035devfs_lookupx(struct vop_lookup_args *ap, int *dm_unlock)
1036{
1037	struct componentname *cnp;
1038	struct vnode *dvp, **vpp;
1039	struct thread *td;
1040	struct devfs_dirent *de, *dd;
1041	struct devfs_dirent **dde;
1042	struct devfs_mount *dmp;
1043	struct mount *mp;
1044	struct cdev *cdev;
1045	int error, flags, nameiop, dvplocked;
1046	char specname[SPECNAMELEN + 1], *pname;
1047
1048	cnp = ap->a_cnp;
1049	vpp = ap->a_vpp;
1050	dvp = ap->a_dvp;
1051	pname = cnp->cn_nameptr;
1052	td = cnp->cn_thread;
1053	flags = cnp->cn_flags;
1054	nameiop = cnp->cn_nameiop;
1055	mp = dvp->v_mount;
1056	dmp = VFSTODEVFS(mp);
1057	dd = dvp->v_data;
1058	*vpp = NULLVP;
1059
1060	if ((flags & ISLASTCN) && nameiop == RENAME)
1061		return (EOPNOTSUPP);
1062
1063	if (dvp->v_type != VDIR)
1064		return (ENOTDIR);
1065
1066	if ((flags & ISDOTDOT) && (dvp->v_vflag & VV_ROOT))
1067		return (EIO);
1068
1069	error = vn_dir_check_exec(dvp, cnp);
1070	if (error != 0)
1071		return (error);
1072
1073	if (cnp->cn_namelen == 1 && *pname == '.') {
1074		if ((flags & ISLASTCN) && nameiop != LOOKUP)
1075			return (EINVAL);
1076		*vpp = dvp;
1077		VREF(dvp);
1078		return (0);
1079	}
1080
1081	if (flags & ISDOTDOT) {
1082		if ((flags & ISLASTCN) && nameiop != LOOKUP)
1083			return (EINVAL);
1084		de = devfs_parent_dirent(dd);
1085		if (de == NULL)
1086			return (ENOENT);
1087		dvplocked = VOP_ISLOCKED(dvp);
1088		VOP_UNLOCK(dvp);
1089		error = devfs_allocv(de, mp, cnp->cn_lkflags & LK_TYPE_MASK,
1090		    vpp);
1091		*dm_unlock = 0;
1092		vn_lock(dvp, dvplocked | LK_RETRY);
1093		return (error);
1094	}
1095
1096	dd = dvp->v_data;
1097	de = devfs_find(dd, cnp->cn_nameptr, cnp->cn_namelen, 0);
1098	while (de == NULL) {	/* While(...) so we can use break */
1099
1100		if (nameiop == DELETE)
1101			return (ENOENT);
1102
1103		/*
1104		 * OK, we didn't have an entry for the name we were asked for
1105		 * so we try to see if anybody can create it on demand.
1106		 */
1107		pname = devfs_fqpn(specname, dmp, dd, cnp);
1108		if (pname == NULL)
1109			break;
1110
1111		cdev = NULL;
1112		DEVFS_DMP_HOLD(dmp);
1113		sx_xunlock(&dmp->dm_lock);
1114		sx_slock(&clone_drain_lock);
1115		EVENTHANDLER_INVOKE(dev_clone,
1116		    td->td_ucred, pname, strlen(pname), &cdev);
1117		sx_sunlock(&clone_drain_lock);
1118
1119		if (cdev == NULL)
1120			sx_xlock(&dmp->dm_lock);
1121		else if (devfs_populate_vp(dvp) != 0) {
1122			*dm_unlock = 0;
1123			sx_xlock(&dmp->dm_lock);
1124			if (DEVFS_DMP_DROP(dmp)) {
1125				sx_xunlock(&dmp->dm_lock);
1126				devfs_unmount_final(dmp);
1127			} else
1128				sx_xunlock(&dmp->dm_lock);
1129			dev_rel(cdev);
1130			return (ENOENT);
1131		}
1132		if (DEVFS_DMP_DROP(dmp)) {
1133			*dm_unlock = 0;
1134			sx_xunlock(&dmp->dm_lock);
1135			devfs_unmount_final(dmp);
1136			if (cdev != NULL)
1137				dev_rel(cdev);
1138			return (ENOENT);
1139		}
1140
1141		if (cdev == NULL)
1142			break;
1143
1144		dev_lock();
1145		dde = &cdev2priv(cdev)->cdp_dirents[dmp->dm_idx];
1146		if (dde != NULL && *dde != NULL)
1147			de = *dde;
1148		dev_unlock();
1149		dev_rel(cdev);
1150		break;
1151	}
1152
1153	if (de == NULL || de->de_flags & DE_WHITEOUT) {
1154		if ((nameiop == CREATE || nameiop == RENAME) &&
1155		    (flags & (LOCKPARENT | WANTPARENT)) && (flags & ISLASTCN)) {
1156			cnp->cn_flags |= SAVENAME;
1157			return (EJUSTRETURN);
1158		}
1159		return (ENOENT);
1160	}
1161
1162	if (devfs_prison_check(de, td))
1163		return (ENOENT);
1164
1165	if ((cnp->cn_nameiop == DELETE) && (flags & ISLASTCN)) {
1166		error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td);
1167		if (error)
1168			return (error);
1169		if (*vpp == dvp) {
1170			VREF(dvp);
1171			*vpp = dvp;
1172			return (0);
1173		}
1174	}
1175	error = devfs_allocv(de, mp, cnp->cn_lkflags & LK_TYPE_MASK, vpp);
1176	*dm_unlock = 0;
1177	return (error);
1178}
1179
1180static int
1181devfs_lookup(struct vop_lookup_args *ap)
1182{
1183	int j;
1184	struct devfs_mount *dmp;
1185	int dm_unlock;
1186
1187	if (devfs_populate_vp(ap->a_dvp) != 0)
1188		return (ENOTDIR);
1189
1190	dmp = VFSTODEVFS(ap->a_dvp->v_mount);
1191	dm_unlock = 1;
1192	j = devfs_lookupx(ap, &dm_unlock);
1193	if (dm_unlock == 1)
1194		sx_xunlock(&dmp->dm_lock);
1195	return (j);
1196}
1197
1198static int
1199devfs_mknod(struct vop_mknod_args *ap)
1200{
1201	struct componentname *cnp;
1202	struct vnode *dvp, **vpp;
1203	struct devfs_dirent *dd, *de;
1204	struct devfs_mount *dmp;
1205	int error;
1206
1207	/*
1208	 * The only type of node we should be creating here is a
1209	 * character device, for anything else return EOPNOTSUPP.
1210	 */
1211	if (ap->a_vap->va_type != VCHR)
1212		return (EOPNOTSUPP);
1213	dvp = ap->a_dvp;
1214	dmp = VFSTODEVFS(dvp->v_mount);
1215
1216	cnp = ap->a_cnp;
1217	vpp = ap->a_vpp;
1218	dd = dvp->v_data;
1219
1220	error = ENOENT;
1221	sx_xlock(&dmp->dm_lock);
1222	TAILQ_FOREACH(de, &dd->de_dlist, de_list) {
1223		if (cnp->cn_namelen != de->de_dirent->d_namlen)
1224			continue;
1225		if (de->de_dirent->d_type == DT_CHR &&
1226		    (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0)
1227			continue;
1228		if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name,
1229		    de->de_dirent->d_namlen) != 0)
1230			continue;
1231		if (de->de_flags & DE_WHITEOUT)
1232			break;
1233		goto notfound;
1234	}
1235	if (de == NULL)
1236		goto notfound;
1237	de->de_flags &= ~DE_WHITEOUT;
1238	error = devfs_allocv(de, dvp->v_mount, LK_EXCLUSIVE, vpp);
1239	return (error);
1240notfound:
1241	sx_xunlock(&dmp->dm_lock);
1242	return (error);
1243}
1244
1245/* ARGSUSED */
1246static int
1247devfs_open(struct vop_open_args *ap)
1248{
1249	struct thread *td = ap->a_td;
1250	struct vnode *vp = ap->a_vp;
1251	struct cdev *dev = vp->v_rdev;
1252	struct file *fp = ap->a_fp;
1253	int error, ref, vlocked;
1254	struct cdevsw *dsw;
1255	struct file *fpop;
1256
1257	if (vp->v_type == VBLK)
1258		return (ENXIO);
1259
1260	if (dev == NULL)
1261		return (ENXIO);
1262
1263	/* Make this field valid before any I/O in d_open. */
1264	if (dev->si_iosize_max == 0)
1265		dev->si_iosize_max = DFLTPHYS;
1266
1267	dsw = dev_refthread(dev, &ref);
1268	if (dsw == NULL)
1269		return (ENXIO);
1270	if (fp == NULL && dsw->d_fdopen != NULL) {
1271		dev_relthread(dev, ref);
1272		return (ENXIO);
1273	}
1274
1275	if (vp->v_type == VCHR)
1276		devfs_usecount_add(vp);
1277
1278	vlocked = VOP_ISLOCKED(vp);
1279	VOP_UNLOCK(vp);
1280
1281	fpop = td->td_fpop;
1282	td->td_fpop = fp;
1283	if (fp != NULL) {
1284		fp->f_data = dev;
1285		fp->f_vnode = vp;
1286	}
1287	if (dsw->d_fdopen != NULL)
1288		error = dsw->d_fdopen(dev, ap->a_mode, td, fp);
1289	else
1290		error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td);
1291	/* Clean up any cdevpriv upon error. */
1292	if (error != 0)
1293		devfs_clear_cdevpriv();
1294	td->td_fpop = fpop;
1295
1296	vn_lock(vp, vlocked | LK_RETRY);
1297	if (error != 0 && vp->v_type == VCHR)
1298		devfs_usecount_sub(vp);
1299
1300	dev_relthread(dev, ref);
1301	if (error != 0) {
1302		if (error == ERESTART)
1303			error = EINTR;
1304		return (error);
1305	}
1306
1307#if 0	/* /dev/console */
1308	KASSERT(fp != NULL, ("Could not vnode bypass device on NULL fp"));
1309#else
1310	if (fp == NULL)
1311		return (error);
1312#endif
1313	if (fp->f_ops == &badfileops)
1314		finit(fp, fp->f_flag, DTYPE_VNODE, dev, &devfs_ops_f);
1315	return (error);
1316}
1317
1318static int
1319devfs_pathconf(struct vop_pathconf_args *ap)
1320{
1321
1322	switch (ap->a_name) {
1323	case _PC_FILESIZEBITS:
1324		*ap->a_retval = 64;
1325		return (0);
1326	case _PC_NAME_MAX:
1327		*ap->a_retval = NAME_MAX;
1328		return (0);
1329	case _PC_LINK_MAX:
1330		*ap->a_retval = INT_MAX;
1331		return (0);
1332	case _PC_SYMLINK_MAX:
1333		*ap->a_retval = MAXPATHLEN;
1334		return (0);
1335	case _PC_MAX_CANON:
1336		if (ap->a_vp->v_vflag & VV_ISTTY) {
1337			*ap->a_retval = MAX_CANON;
1338			return (0);
1339		}
1340		return (EINVAL);
1341	case _PC_MAX_INPUT:
1342		if (ap->a_vp->v_vflag & VV_ISTTY) {
1343			*ap->a_retval = MAX_INPUT;
1344			return (0);
1345		}
1346		return (EINVAL);
1347	case _PC_VDISABLE:
1348		if (ap->a_vp->v_vflag & VV_ISTTY) {
1349			*ap->a_retval = _POSIX_VDISABLE;
1350			return (0);
1351		}
1352		return (EINVAL);
1353	case _PC_MAC_PRESENT:
1354#ifdef MAC
1355		/*
1356		 * If MAC is enabled, devfs automatically supports
1357		 * trivial non-persistant label storage.
1358		 */
1359		*ap->a_retval = 1;
1360#else
1361		*ap->a_retval = 0;
1362#endif
1363		return (0);
1364	case _PC_CHOWN_RESTRICTED:
1365		*ap->a_retval = 1;
1366		return (0);
1367	default:
1368		return (vop_stdpathconf(ap));
1369	}
1370	/* NOTREACHED */
1371}
1372
1373/* ARGSUSED */
1374static int
1375devfs_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td)
1376{
1377	struct cdev *dev;
1378	struct cdevsw *dsw;
1379	int error, ref;
1380	struct file *fpop;
1381
1382	fpop = td->td_fpop;
1383	error = devfs_fp_check(fp, &dev, &dsw, &ref);
1384	if (error != 0) {
1385		error = vnops.fo_poll(fp, events, cred, td);
1386		return (error);
1387	}
1388	error = dsw->d_poll(dev, events, td);
1389	td->td_fpop = fpop;
1390	dev_relthread(dev, ref);
1391	return(error);
1392}
1393
1394/*
1395 * Print out the contents of a special device vnode.
1396 */
1397static int
1398devfs_print(struct vop_print_args *ap)
1399{
1400
1401	printf("\tdev %s\n", devtoname(ap->a_vp->v_rdev));
1402	return (0);
1403}
1404
1405static int
1406devfs_read_f(struct file *fp, struct uio *uio, struct ucred *cred,
1407    int flags, struct thread *td)
1408{
1409	struct cdev *dev;
1410	int ioflag, error, ref;
1411	ssize_t resid;
1412	struct cdevsw *dsw;
1413	struct file *fpop;
1414
1415	if (uio->uio_resid > DEVFS_IOSIZE_MAX)
1416		return (EINVAL);
1417	fpop = td->td_fpop;
1418	error = devfs_fp_check(fp, &dev, &dsw, &ref);
1419	if (error != 0) {
1420		error = vnops.fo_read(fp, uio, cred, flags, td);
1421		return (error);
1422	}
1423	resid = uio->uio_resid;
1424	ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT);
1425	if (ioflag & O_DIRECT)
1426		ioflag |= IO_DIRECT;
1427
1428	foffset_lock_uio(fp, uio, flags | FOF_NOLOCK);
1429	error = dsw->d_read(dev, uio, ioflag);
1430	if (uio->uio_resid != resid || (error == 0 && resid != 0))
1431		devfs_timestamp(&dev->si_atime);
1432	td->td_fpop = fpop;
1433	dev_relthread(dev, ref);
1434
1435	foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF_R);
1436	return (error);
1437}
1438
1439static int
1440devfs_readdir(struct vop_readdir_args *ap)
1441{
1442	int error;
1443	struct uio *uio;
1444	struct dirent *dp;
1445	struct devfs_dirent *dd;
1446	struct devfs_dirent *de;
1447	struct devfs_mount *dmp;
1448	off_t off;
1449	int *tmp_ncookies = NULL;
1450
1451	if (ap->a_vp->v_type != VDIR)
1452		return (ENOTDIR);
1453
1454	uio = ap->a_uio;
1455	if (uio->uio_offset < 0)
1456		return (EINVAL);
1457
1458	/*
1459	 * XXX: This is a temporary hack to get around this filesystem not
1460	 * supporting cookies. We store the location of the ncookies pointer
1461	 * in a temporary variable before calling vfs_subr.c:vfs_read_dirent()
1462	 * and set the number of cookies to 0. We then set the pointer to
1463	 * NULL so that vfs_read_dirent doesn't try to call realloc() on
1464	 * ap->a_cookies. Later in this function, we restore the ap->a_ncookies
1465	 * pointer to its original location before returning to the caller.
1466	 */
1467	if (ap->a_ncookies != NULL) {
1468		tmp_ncookies = ap->a_ncookies;
1469		*ap->a_ncookies = 0;
1470		ap->a_ncookies = NULL;
1471	}
1472
1473	dmp = VFSTODEVFS(ap->a_vp->v_mount);
1474	if (devfs_populate_vp(ap->a_vp) != 0) {
1475		if (tmp_ncookies != NULL)
1476			ap->a_ncookies = tmp_ncookies;
1477		return (EIO);
1478	}
1479	error = 0;
1480	de = ap->a_vp->v_data;
1481	off = 0;
1482	TAILQ_FOREACH(dd, &de->de_dlist, de_list) {
1483		KASSERT(dd->de_cdp != (void *)0xdeadc0de, ("%s %d\n", __func__, __LINE__));
1484		if (dd->de_flags & (DE_COVERED | DE_WHITEOUT))
1485			continue;
1486		if (devfs_prison_check(dd, uio->uio_td))
1487			continue;
1488		if (dd->de_dirent->d_type == DT_DIR)
1489			de = dd->de_dir;
1490		else
1491			de = dd;
1492		dp = dd->de_dirent;
1493		MPASS(dp->d_reclen == GENERIC_DIRSIZ(dp));
1494		if (dp->d_reclen > uio->uio_resid)
1495			break;
1496		dp->d_fileno = de->de_inode;
1497		/* NOTE: d_off is the offset for the *next* entry. */
1498		dp->d_off = off + dp->d_reclen;
1499		if (off >= uio->uio_offset) {
1500			error = vfs_read_dirent(ap, dp, off);
1501			if (error)
1502				break;
1503		}
1504		off += dp->d_reclen;
1505	}
1506	sx_xunlock(&dmp->dm_lock);
1507	uio->uio_offset = off;
1508
1509	/*
1510	 * Restore ap->a_ncookies if it wasn't originally NULL in the first
1511	 * place.
1512	 */
1513	if (tmp_ncookies != NULL)
1514		ap->a_ncookies = tmp_ncookies;
1515
1516	return (error);
1517}
1518
1519static int
1520devfs_readlink(struct vop_readlink_args *ap)
1521{
1522	struct devfs_dirent *de;
1523
1524	de = ap->a_vp->v_data;
1525	return (uiomove(de->de_symlink, strlen(de->de_symlink), ap->a_uio));
1526}
1527
1528static void
1529devfs_reclaiml(struct vnode *vp)
1530{
1531	struct devfs_dirent *de;
1532
1533	mtx_assert(&devfs_de_interlock, MA_OWNED);
1534	de = vp->v_data;
1535	if (de != NULL) {
1536		MPASS(de->de_usecount == 0);
1537		de->de_vnode = NULL;
1538		vp->v_data = NULL;
1539	}
1540}
1541
1542static int
1543devfs_reclaim(struct vop_reclaim_args *ap)
1544{
1545	struct vnode *vp;
1546
1547	vp = ap->a_vp;
1548	mtx_lock(&devfs_de_interlock);
1549	devfs_reclaiml(vp);
1550	mtx_unlock(&devfs_de_interlock);
1551	return (0);
1552}
1553
1554static int
1555devfs_reclaim_vchr(struct vop_reclaim_args *ap)
1556{
1557	struct vnode *vp;
1558	struct cdev *dev;
1559
1560	vp = ap->a_vp;
1561	MPASS(vp->v_type == VCHR);
1562
1563	mtx_lock(&devfs_de_interlock);
1564	VI_LOCK(vp);
1565	devfs_usecount_subl(vp);
1566	devfs_reclaiml(vp);
1567	mtx_unlock(&devfs_de_interlock);
1568	dev_lock();
1569	dev = vp->v_rdev;
1570	vp->v_rdev = NULL;
1571	dev_unlock();
1572	VI_UNLOCK(vp);
1573	if (dev != NULL)
1574		dev_rel(dev);
1575	return (0);
1576}
1577
1578static int
1579devfs_remove(struct vop_remove_args *ap)
1580{
1581	struct vnode *dvp = ap->a_dvp;
1582	struct vnode *vp = ap->a_vp;
1583	struct devfs_dirent *dd;
1584	struct devfs_dirent *de, *de_covered;
1585	struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount);
1586
1587	ASSERT_VOP_ELOCKED(dvp, "devfs_remove");
1588	ASSERT_VOP_ELOCKED(vp, "devfs_remove");
1589
1590	sx_xlock(&dmp->dm_lock);
1591	dd = ap->a_dvp->v_data;
1592	de = vp->v_data;
1593	if (de->de_cdp == NULL) {
1594		TAILQ_REMOVE(&dd->de_dlist, de, de_list);
1595		if (de->de_dirent->d_type == DT_LNK) {
1596			de_covered = devfs_find(dd, de->de_dirent->d_name,
1597			    de->de_dirent->d_namlen, 0);
1598			if (de_covered != NULL)
1599				de_covered->de_flags &= ~DE_COVERED;
1600		}
1601		/* We need to unlock dvp because devfs_delete() may lock it. */
1602		VOP_UNLOCK(vp);
1603		if (dvp != vp)
1604			VOP_UNLOCK(dvp);
1605		devfs_delete(dmp, de, 0);
1606		sx_xunlock(&dmp->dm_lock);
1607		if (dvp != vp)
1608			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
1609		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1610	} else {
1611		de->de_flags |= DE_WHITEOUT;
1612		sx_xunlock(&dmp->dm_lock);
1613	}
1614	return (0);
1615}
1616
1617/*
1618 * Revoke is called on a tty when a terminal session ends.  The vnode
1619 * is orphaned by setting v_op to deadfs so we need to let go of it
1620 * as well so that we create a new one next time around.
1621 *
1622 */
1623static int
1624devfs_revoke(struct vop_revoke_args *ap)
1625{
1626	struct vnode *vp = ap->a_vp, *vp2;
1627	struct cdev *dev;
1628	struct cdev_priv *cdp;
1629	struct devfs_dirent *de;
1630	enum vgetstate vs;
1631	u_int i;
1632
1633	KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL"));
1634
1635	dev = vp->v_rdev;
1636	cdp = cdev2priv(dev);
1637
1638	dev_lock();
1639	cdp->cdp_inuse++;
1640	dev_unlock();
1641
1642	vhold(vp);
1643	vgone(vp);
1644	vdrop(vp);
1645
1646	VOP_UNLOCK(vp);
1647 loop:
1648	for (;;) {
1649		mtx_lock(&devfs_de_interlock);
1650		dev_lock();
1651		vp2 = NULL;
1652		for (i = 0; i <= cdp->cdp_maxdirent; i++) {
1653			de = cdp->cdp_dirents[i];
1654			if (de == NULL)
1655				continue;
1656
1657			vp2 = de->de_vnode;
1658			if (vp2 != NULL) {
1659				dev_unlock();
1660				vs = vget_prep(vp2);
1661				mtx_unlock(&devfs_de_interlock);
1662				if (vget_finish(vp2, LK_EXCLUSIVE, vs) != 0)
1663					goto loop;
1664				vhold(vp2);
1665				vgone(vp2);
1666				vdrop(vp2);
1667				vput(vp2);
1668				break;
1669			}
1670		}
1671		if (vp2 != NULL) {
1672			continue;
1673		}
1674		dev_unlock();
1675		mtx_unlock(&devfs_de_interlock);
1676		break;
1677	}
1678	dev_lock();
1679	cdp->cdp_inuse--;
1680	if (!(cdp->cdp_flags & CDP_ACTIVE) && cdp->cdp_inuse == 0) {
1681		TAILQ_REMOVE(&cdevp_list, cdp, cdp_list);
1682		dev_unlock();
1683		dev_rel(&cdp->cdp_c);
1684	} else
1685		dev_unlock();
1686
1687	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1688	return (0);
1689}
1690
1691static int
1692devfs_rioctl(struct vop_ioctl_args *ap)
1693{
1694	struct vnode *vp;
1695	struct devfs_mount *dmp;
1696	int error;
1697
1698	vp = ap->a_vp;
1699	vn_lock(vp, LK_SHARED | LK_RETRY);
1700	if (VN_IS_DOOMED(vp)) {
1701		VOP_UNLOCK(vp);
1702		return (EBADF);
1703	}
1704	dmp = VFSTODEVFS(vp->v_mount);
1705	sx_xlock(&dmp->dm_lock);
1706	VOP_UNLOCK(vp);
1707	DEVFS_DMP_HOLD(dmp);
1708	devfs_populate(dmp);
1709	if (DEVFS_DMP_DROP(dmp)) {
1710		sx_xunlock(&dmp->dm_lock);
1711		devfs_unmount_final(dmp);
1712		return (ENOENT);
1713	}
1714	error = devfs_rules_ioctl(dmp, ap->a_command, ap->a_data, ap->a_td);
1715	sx_xunlock(&dmp->dm_lock);
1716	return (error);
1717}
1718
1719static int
1720devfs_rread(struct vop_read_args *ap)
1721{
1722
1723	if (ap->a_vp->v_type != VDIR)
1724		return (EINVAL);
1725	return (VOP_READDIR(ap->a_vp, ap->a_uio, ap->a_cred, NULL, NULL, NULL));
1726}
1727
1728static int
1729devfs_setattr(struct vop_setattr_args *ap)
1730{
1731	struct devfs_dirent *de;
1732	struct vattr *vap;
1733	struct vnode *vp;
1734	struct thread *td;
1735	int c, error;
1736	uid_t uid;
1737	gid_t gid;
1738
1739	vap = ap->a_vap;
1740	vp = ap->a_vp;
1741	td = curthread;
1742	if ((vap->va_type != VNON) ||
1743	    (vap->va_nlink != VNOVAL) ||
1744	    (vap->va_fsid != VNOVAL) ||
1745	    (vap->va_fileid != VNOVAL) ||
1746	    (vap->va_blocksize != VNOVAL) ||
1747	    (vap->va_flags != VNOVAL && vap->va_flags != 0) ||
1748	    (vap->va_rdev != VNOVAL) ||
1749	    ((int)vap->va_bytes != VNOVAL) ||
1750	    (vap->va_gen != VNOVAL)) {
1751		return (EINVAL);
1752	}
1753
1754	error = devfs_populate_vp(vp);
1755	if (error != 0)
1756		return (error);
1757
1758	de = vp->v_data;
1759	if (vp->v_type == VDIR)
1760		de = de->de_dir;
1761
1762	c = 0;
1763	if (vap->va_uid == (uid_t)VNOVAL)
1764		uid = de->de_uid;
1765	else
1766		uid = vap->va_uid;
1767	if (vap->va_gid == (gid_t)VNOVAL)
1768		gid = de->de_gid;
1769	else
1770		gid = vap->va_gid;
1771	if (uid != de->de_uid || gid != de->de_gid) {
1772		if ((ap->a_cred->cr_uid != de->de_uid) || uid != de->de_uid ||
1773		    (gid != de->de_gid && !groupmember(gid, ap->a_cred))) {
1774			error = priv_check(td, PRIV_VFS_CHOWN);
1775			if (error != 0)
1776				goto ret;
1777		}
1778		de->de_uid = uid;
1779		de->de_gid = gid;
1780		c = 1;
1781	}
1782
1783	if (vap->va_mode != (mode_t)VNOVAL) {
1784		if (ap->a_cred->cr_uid != de->de_uid) {
1785			error = priv_check(td, PRIV_VFS_ADMIN);
1786			if (error != 0)
1787				goto ret;
1788		}
1789		de->de_mode = vap->va_mode;
1790		c = 1;
1791	}
1792
1793	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
1794		error = vn_utimes_perm(vp, vap, ap->a_cred, td);
1795		if (error != 0)
1796			goto ret;
1797		if (vap->va_atime.tv_sec != VNOVAL) {
1798			if (vp->v_type == VCHR)
1799				vp->v_rdev->si_atime = vap->va_atime;
1800			else
1801				de->de_atime = vap->va_atime;
1802		}
1803		if (vap->va_mtime.tv_sec != VNOVAL) {
1804			if (vp->v_type == VCHR)
1805				vp->v_rdev->si_mtime = vap->va_mtime;
1806			else
1807				de->de_mtime = vap->va_mtime;
1808		}
1809		c = 1;
1810	}
1811
1812	if (c) {
1813		if (vp->v_type == VCHR)
1814			vfs_timestamp(&vp->v_rdev->si_ctime);
1815		else
1816			vfs_timestamp(&de->de_mtime);
1817	}
1818
1819ret:
1820	sx_xunlock(&VFSTODEVFS(vp->v_mount)->dm_lock);
1821	return (error);
1822}
1823
1824#ifdef MAC
1825static int
1826devfs_setlabel(struct vop_setlabel_args *ap)
1827{
1828	struct vnode *vp;
1829	struct devfs_dirent *de;
1830
1831	vp = ap->a_vp;
1832	de = vp->v_data;
1833
1834	mac_vnode_relabel(ap->a_cred, vp, ap->a_label);
1835	mac_devfs_update(vp->v_mount, de, vp);
1836
1837	return (0);
1838}
1839#endif
1840
1841static int
1842devfs_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td)
1843{
1844
1845	return (vnops.fo_stat(fp, sb, cred, td));
1846}
1847
1848static int
1849devfs_symlink(struct vop_symlink_args *ap)
1850{
1851	int i, error;
1852	struct devfs_dirent *dd;
1853	struct devfs_dirent *de, *de_covered, *de_dotdot;
1854	struct devfs_mount *dmp;
1855
1856	error = priv_check(curthread, PRIV_DEVFS_SYMLINK);
1857	if (error)
1858		return(error);
1859	dmp = VFSTODEVFS(ap->a_dvp->v_mount);
1860	if (devfs_populate_vp(ap->a_dvp) != 0)
1861		return (ENOENT);
1862
1863	dd = ap->a_dvp->v_data;
1864	de = devfs_newdirent(ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen);
1865	de->de_flags = DE_USER;
1866	de->de_uid = 0;
1867	de->de_gid = 0;
1868	de->de_mode = 0755;
1869	de->de_inode = alloc_unr(devfs_inos);
1870	de->de_dir = dd;
1871	de->de_dirent->d_type = DT_LNK;
1872	i = strlen(ap->a_target) + 1;
1873	de->de_symlink = malloc(i, M_DEVFS, M_WAITOK);
1874	bcopy(ap->a_target, de->de_symlink, i);
1875#ifdef MAC
1876	mac_devfs_create_symlink(ap->a_cnp->cn_cred, dmp->dm_mount, dd, de);
1877#endif
1878	de_covered = devfs_find(dd, de->de_dirent->d_name,
1879	    de->de_dirent->d_namlen, 0);
1880	if (de_covered != NULL) {
1881		if ((de_covered->de_flags & DE_USER) != 0) {
1882			devfs_delete(dmp, de, DEVFS_DEL_NORECURSE);
1883			sx_xunlock(&dmp->dm_lock);
1884			return (EEXIST);
1885		}
1886		KASSERT((de_covered->de_flags & DE_COVERED) == 0,
1887		    ("devfs_symlink: entry %p already covered", de_covered));
1888		de_covered->de_flags |= DE_COVERED;
1889	}
1890
1891	de_dotdot = TAILQ_FIRST(&dd->de_dlist);		/* "." */
1892	de_dotdot = TAILQ_NEXT(de_dotdot, de_list);	/* ".." */
1893	TAILQ_INSERT_AFTER(&dd->de_dlist, de_dotdot, de, de_list);
1894	devfs_dir_ref_de(dmp, dd);
1895	devfs_rules_apply(dmp, de);
1896
1897	return (devfs_allocv(de, ap->a_dvp->v_mount, LK_EXCLUSIVE, ap->a_vpp));
1898}
1899
1900static int
1901devfs_truncate_f(struct file *fp, off_t length, struct ucred *cred, struct thread *td)
1902{
1903
1904	return (vnops.fo_truncate(fp, length, cred, td));
1905}
1906
1907static int
1908devfs_write_f(struct file *fp, struct uio *uio, struct ucred *cred,
1909    int flags, struct thread *td)
1910{
1911	struct cdev *dev;
1912	int error, ioflag, ref;
1913	ssize_t resid;
1914	struct cdevsw *dsw;
1915	struct file *fpop;
1916
1917	if (uio->uio_resid > DEVFS_IOSIZE_MAX)
1918		return (EINVAL);
1919	fpop = td->td_fpop;
1920	error = devfs_fp_check(fp, &dev, &dsw, &ref);
1921	if (error != 0) {
1922		error = vnops.fo_write(fp, uio, cred, flags, td);
1923		return (error);
1924	}
1925	KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td));
1926	ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC);
1927	if (ioflag & O_DIRECT)
1928		ioflag |= IO_DIRECT;
1929	foffset_lock_uio(fp, uio, flags | FOF_NOLOCK);
1930
1931	resid = uio->uio_resid;
1932
1933	error = dsw->d_write(dev, uio, ioflag);
1934	if (uio->uio_resid != resid || (error == 0 && resid != 0)) {
1935		devfs_timestamp(&dev->si_ctime);
1936		dev->si_mtime = dev->si_ctime;
1937	}
1938	td->td_fpop = fpop;
1939	dev_relthread(dev, ref);
1940
1941	foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF_W);
1942	return (error);
1943}
1944
1945static int
1946devfs_mmap_f(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
1947    vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
1948    struct thread *td)
1949{
1950	struct cdev *dev;
1951	struct cdevsw *dsw;
1952	struct mount *mp;
1953	struct vnode *vp;
1954	struct file *fpop;
1955	vm_object_t object;
1956	vm_prot_t maxprot;
1957	int error, ref;
1958
1959	vp = fp->f_vnode;
1960
1961	/*
1962	 * Ensure that file and memory protections are
1963	 * compatible.
1964	 */
1965	mp = vp->v_mount;
1966	if (mp != NULL && (mp->mnt_flag & MNT_NOEXEC) != 0) {
1967		maxprot = VM_PROT_NONE;
1968		if ((prot & VM_PROT_EXECUTE) != 0)
1969			return (EACCES);
1970	} else
1971		maxprot = VM_PROT_EXECUTE;
1972	if ((fp->f_flag & FREAD) != 0)
1973		maxprot |= VM_PROT_READ;
1974	else if ((prot & VM_PROT_READ) != 0)
1975		return (EACCES);
1976
1977	/*
1978	 * If we are sharing potential changes via MAP_SHARED and we
1979	 * are trying to get write permission although we opened it
1980	 * without asking for it, bail out.
1981	 *
1982	 * Note that most character devices always share mappings.
1983	 * The one exception is that D_MMAP_ANON devices
1984	 * (i.e. /dev/zero) permit private writable mappings.
1985	 *
1986	 * Rely on vm_mmap_cdev() to fail invalid MAP_PRIVATE requests
1987	 * as well as updating maxprot to permit writing for
1988	 * D_MMAP_ANON devices rather than doing that here.
1989	 */
1990	if ((flags & MAP_SHARED) != 0) {
1991		if ((fp->f_flag & FWRITE) != 0)
1992			maxprot |= VM_PROT_WRITE;
1993		else if ((prot & VM_PROT_WRITE) != 0)
1994			return (EACCES);
1995	}
1996	maxprot &= cap_maxprot;
1997
1998	fpop = td->td_fpop;
1999	error = devfs_fp_check(fp, &dev, &dsw, &ref);
2000	if (error != 0)
2001		return (error);
2002
2003	error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, dev, dsw, &foff,
2004	    &object);
2005	td->td_fpop = fpop;
2006	dev_relthread(dev, ref);
2007	if (error != 0)
2008		return (error);
2009
2010	error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object,
2011	    foff, FALSE, td);
2012	if (error != 0)
2013		vm_object_deallocate(object);
2014	return (error);
2015}
2016
2017dev_t
2018dev2udev(struct cdev *x)
2019{
2020	if (x == NULL)
2021		return (NODEV);
2022	return (cdev2priv(x)->cdp_inode);
2023}
2024
2025static struct fileops devfs_ops_f = {
2026	.fo_read =	devfs_read_f,
2027	.fo_write =	devfs_write_f,
2028	.fo_truncate =	devfs_truncate_f,
2029	.fo_ioctl =	devfs_ioctl_f,
2030	.fo_poll =	devfs_poll_f,
2031	.fo_kqfilter =	devfs_kqfilter_f,
2032	.fo_stat =	devfs_stat_f,
2033	.fo_close =	devfs_close_f,
2034	.fo_chmod =	vn_chmod,
2035	.fo_chown =	vn_chown,
2036	.fo_sendfile =	vn_sendfile,
2037	.fo_seek =	vn_seek,
2038	.fo_fill_kinfo = vn_fill_kinfo,
2039	.fo_mmap =	devfs_mmap_f,
2040	.fo_flags =	DFLAG_PASSABLE | DFLAG_SEEKABLE
2041};
2042
2043/* Vops for non-CHR vnodes in /dev. */
2044static struct vop_vector devfs_vnodeops = {
2045	.vop_default =		&default_vnodeops,
2046
2047	.vop_access =		devfs_access,
2048	.vop_getattr =		devfs_getattr,
2049	.vop_ioctl =		devfs_rioctl,
2050	.vop_lookup =		devfs_lookup,
2051	.vop_mknod =		devfs_mknod,
2052	.vop_pathconf =		devfs_pathconf,
2053	.vop_read =		devfs_rread,
2054	.vop_readdir =		devfs_readdir,
2055	.vop_readlink =		devfs_readlink,
2056	.vop_reclaim =		devfs_reclaim,
2057	.vop_remove =		devfs_remove,
2058	.vop_revoke =		devfs_revoke,
2059	.vop_setattr =		devfs_setattr,
2060#ifdef MAC
2061	.vop_setlabel =		devfs_setlabel,
2062#endif
2063	.vop_symlink =		devfs_symlink,
2064	.vop_vptocnp =		devfs_vptocnp,
2065	.vop_lock1 =		vop_lock,
2066	.vop_unlock =		vop_unlock,
2067	.vop_islocked =		vop_islocked,
2068};
2069VFS_VOP_VECTOR_REGISTER(devfs_vnodeops);
2070
2071/* Vops for VCHR vnodes in /dev. */
2072static struct vop_vector devfs_specops = {
2073	.vop_default =		&default_vnodeops,
2074
2075	.vop_access =		devfs_access,
2076	.vop_bmap =		VOP_PANIC,
2077	.vop_close =		devfs_close,
2078	.vop_create =		VOP_PANIC,
2079	.vop_fsync =		vop_stdfsync,
2080	.vop_getattr =		devfs_getattr,
2081	.vop_ioctl =		devfs_ioctl,
2082	.vop_link =		VOP_PANIC,
2083	.vop_mkdir =		VOP_PANIC,
2084	.vop_mknod =		VOP_PANIC,
2085	.vop_open =		devfs_open,
2086	.vop_pathconf =		devfs_pathconf,
2087	.vop_poll =		dead_poll,
2088	.vop_print =		devfs_print,
2089	.vop_read =		dead_read,
2090	.vop_readdir =		VOP_PANIC,
2091	.vop_readlink =		VOP_PANIC,
2092	.vop_reallocblks =	VOP_PANIC,
2093	.vop_reclaim =		devfs_reclaim_vchr,
2094	.vop_remove =		devfs_remove,
2095	.vop_rename =		VOP_PANIC,
2096	.vop_revoke =		devfs_revoke,
2097	.vop_rmdir =		VOP_PANIC,
2098	.vop_setattr =		devfs_setattr,
2099#ifdef MAC
2100	.vop_setlabel =		devfs_setlabel,
2101#endif
2102	.vop_strategy =		VOP_PANIC,
2103	.vop_symlink =		VOP_PANIC,
2104	.vop_vptocnp =		devfs_vptocnp,
2105	.vop_write =		dead_write,
2106	.vop_lock1 =		vop_lock,
2107	.vop_unlock =		vop_unlock,
2108	.vop_islocked =		vop_islocked,
2109};
2110VFS_VOP_VECTOR_REGISTER(devfs_specops);
2111
2112/*
2113 * Our calling convention to the device drivers used to be that we passed
2114 * vnode.h IO_* flags to read()/write(), but we're moving to fcntl.h O_
2115 * flags instead since that's what open(), close() and ioctl() takes and
2116 * we don't really want vnode.h in device drivers.
2117 * We solved the source compatibility by redefining some vnode flags to
2118 * be the same as the fcntl ones and by sending down the bitwise OR of
2119 * the respective fcntl/vnode flags.  These CTASSERTS make sure nobody
2120 * pulls the rug out under this.
2121 */
2122CTASSERT(O_NONBLOCK == IO_NDELAY);
2123CTASSERT(O_FSYNC == IO_SYNC);
2124