1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
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 * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vnops.c 1.43
33 */
34
35/*
36 * TODO:
37 *	mkdir: want it ?
38 */
39
40#include <sys/param.h>
41#include <sys/systm.h>
42#include <sys/conf.h>
43#include <sys/dirent.h>
44#include <sys/eventhandler.h>
45#include <sys/fcntl.h>
46#include <sys/file.h>
47#include <sys/filedesc.h>
48#include <sys/filio.h>
49#include <sys/jail.h>
50#include <sys/kernel.h>
51#include <sys/limits.h>
52#include <sys/lock.h>
53#include <sys/malloc.h>
54#include <sys/mman.h>
55#include <sys/mount.h>
56#include <sys/namei.h>
57#include <sys/priv.h>
58#include <sys/proc.h>
59#include <sys/stat.h>
60#include <sys/sx.h>
61#include <sys/sysctl.h>
62#include <sys/time.h>
63#include <sys/ttycom.h>
64#include <sys/unistd.h>
65#include <sys/vnode.h>
66
67static struct vop_vector devfs_vnodeops;
68static struct vop_vector devfs_specops;
69static struct fileops devfs_ops_f;
70
71#include <fs/devfs/devfs.h>
72#include <fs/devfs/devfs_int.h>
73
74#include <security/mac/mac_framework.h>
75
76#include <vm/vm.h>
77#include <vm/vm_extern.h>
78#include <vm/vm_object.h>
79
80static MALLOC_DEFINE(M_CDEVPDATA, "DEVFSP", "Metainfo for cdev-fp data");
81
82struct mtx	devfs_de_interlock;
83MTX_SYSINIT(devfs_de_interlock, &devfs_de_interlock, "devfs interlock", MTX_DEF);
84struct mtx	cdevpriv_mtx;
85MTX_SYSINIT(cdevpriv_mtx, &cdevpriv_mtx, "cdevpriv lock", MTX_DEF);
86
87SYSCTL_DECL(_vfs_devfs);
88
89static int devfs_dotimes;
90SYSCTL_INT(_vfs_devfs, OID_AUTO, dotimes, CTLFLAG_RW,
91    &devfs_dotimes, 0, "Update timestamps on DEVFS with default precision");
92
93/*
94 * Update devfs node timestamp.  Note that updates are unlocked and
95 * stat(2) could see partially updated times.
96 */
97static void
98devfs_timestamp(struct timespec *tsp)
99{
100	time_t ts;
101
102	if (devfs_dotimes) {
103		vfs_timestamp(tsp);
104	} else {
105		ts = time_second;
106		if (tsp->tv_sec != ts) {
107			tsp->tv_sec = ts;
108			tsp->tv_nsec = 0;
109		}
110	}
111}
112
113static int
114devfs_fp_check(struct file *fp, struct cdev **devp, struct cdevsw **dswp,
115    int *ref)
116{
117	*dswp = devvn_refthread(fp->f_vnode, devp, ref);
118	if (*dswp == NULL || *devp != fp->f_data) {
119		if (*dswp != NULL)
120			dev_relthread(*devp, *ref);
121		return (ENXIO);
122	}
123	KASSERT((*devp)->si_refcount > 0,
124	    ("devfs: un-referenced struct cdev *(%s)", devtoname(*devp)));
125	if (*dswp == NULL)
126		return (ENXIO);
127	curthread->td_fpop = fp;
128	return (0);
129}
130
131int
132devfs_get_cdevpriv(void **datap)
133{
134	struct file *fp;
135	struct cdev_privdata *p;
136	int error;
137
138	fp = curthread->td_fpop;
139	if (fp == NULL)
140		return (EBADF);
141	p = fp->f_cdevpriv;
142	if (p != NULL) {
143		error = 0;
144		*datap = p->cdpd_data;
145	} else
146		error = ENOENT;
147	return (error);
148}
149
150int
151devfs_set_cdevpriv(void *priv, d_priv_dtor_t *priv_dtr)
152{
153	struct file *fp;
154	struct cdev_priv *cdp;
155	struct cdev_privdata *p;
156	int error;
157
158	fp = curthread->td_fpop;
159	if (fp == NULL)
160		return (ENOENT);
161	cdp = cdev2priv((struct cdev *)fp->f_data);
162	p = malloc(sizeof(struct cdev_privdata), M_CDEVPDATA, M_WAITOK);
163	p->cdpd_data = priv;
164	p->cdpd_dtr = priv_dtr;
165	p->cdpd_fp = fp;
166	mtx_lock(&cdevpriv_mtx);
167	if (fp->f_cdevpriv == NULL) {
168		LIST_INSERT_HEAD(&cdp->cdp_fdpriv, p, cdpd_list);
169		fp->f_cdevpriv = p;
170		mtx_unlock(&cdevpriv_mtx);
171		error = 0;
172	} else {
173		mtx_unlock(&cdevpriv_mtx);
174		free(p, M_CDEVPDATA);
175		error = EBUSY;
176	}
177	return (error);
178}
179
180int
181devfs_foreach_cdevpriv(struct cdev *dev, int (*cb)(void *data, void *arg),
182    void *arg)
183{
184	struct cdev_priv *cdp;
185	struct cdev_privdata *p;
186	int error;
187
188	cdp = cdev2priv(dev);
189	error = 0;
190	mtx_lock(&cdevpriv_mtx);
191	LIST_FOREACH(p, &cdp->cdp_fdpriv, cdpd_list) {
192		error = cb(p->cdpd_data, arg);
193		if (error != 0)
194			break;
195	}
196	mtx_unlock(&cdevpriv_mtx);
197	return (error);
198}
199
200void
201devfs_destroy_cdevpriv(struct cdev_privdata *p)
202{
203
204	mtx_assert(&cdevpriv_mtx, MA_OWNED);
205	KASSERT(p->cdpd_fp->f_cdevpriv == p,
206	    ("devfs_destoy_cdevpriv %p != %p", p->cdpd_fp->f_cdevpriv, p));
207	p->cdpd_fp->f_cdevpriv = NULL;
208	LIST_REMOVE(p, cdpd_list);
209	mtx_unlock(&cdevpriv_mtx);
210	(p->cdpd_dtr)(p->cdpd_data);
211	free(p, M_CDEVPDATA);
212}
213
214static void
215devfs_fpdrop(struct file *fp)
216{
217	struct cdev_privdata *p;
218
219	mtx_lock(&cdevpriv_mtx);
220	if ((p = fp->f_cdevpriv) == NULL) {
221		mtx_unlock(&cdevpriv_mtx);
222		return;
223	}
224	devfs_destroy_cdevpriv(p);
225}
226
227void
228devfs_clear_cdevpriv(void)
229{
230	struct file *fp;
231
232	fp = curthread->td_fpop;
233	if (fp == NULL)
234		return;
235	devfs_fpdrop(fp);
236}
237
238static void
239devfs_usecount_add(struct vnode *vp)
240{
241	struct devfs_dirent *de;
242	struct cdev *dev;
243
244	mtx_lock(&devfs_de_interlock);
245	VI_LOCK(vp);
246	VNPASS(vp->v_type == VCHR || vp->v_type == VBAD, vp);
247	if (VN_IS_DOOMED(vp)) {
248		goto out_unlock;
249	}
250
251	de = vp->v_data;
252	dev = vp->v_rdev;
253	MPASS(de != NULL);
254	MPASS(dev != NULL);
255	dev->si_usecount++;
256	de->de_usecount++;
257out_unlock:
258	VI_UNLOCK(vp);
259	mtx_unlock(&devfs_de_interlock);
260}
261
262static void
263devfs_usecount_subl(struct vnode *vp)
264{
265	struct devfs_dirent *de;
266	struct cdev *dev;
267
268	mtx_assert(&devfs_de_interlock, MA_OWNED);
269	ASSERT_VI_LOCKED(vp, __func__);
270	VNPASS(vp->v_type == VCHR || vp->v_type == VBAD, vp);
271
272	de = vp->v_data;
273	dev = vp->v_rdev;
274	if (de == NULL)
275		return;
276	if (dev == NULL) {
277		MPASS(de->de_usecount == 0);
278		return;
279	}
280	if (dev->si_usecount < de->de_usecount)
281		panic("%s: si_usecount underflow for dev %p "
282		    "(has %ld, dirent has %d)\n",
283		    __func__, dev, dev->si_usecount, de->de_usecount);
284	if (VN_IS_DOOMED(vp)) {
285		dev->si_usecount -= de->de_usecount;
286		de->de_usecount = 0;
287	} else {
288		if (de->de_usecount == 0)
289			panic("%s: de_usecount underflow for dev %p\n",
290			    __func__, dev);
291		dev->si_usecount--;
292		de->de_usecount--;
293	}
294}
295
296static void
297devfs_usecount_sub(struct vnode *vp)
298{
299
300	mtx_lock(&devfs_de_interlock);
301	VI_LOCK(vp);
302	devfs_usecount_subl(vp);
303	VI_UNLOCK(vp);
304	mtx_unlock(&devfs_de_interlock);
305}
306
307static int
308devfs_usecountl(struct vnode *vp)
309{
310
311	VNPASS(vp->v_type == VCHR, vp);
312	mtx_assert(&devfs_de_interlock, MA_OWNED);
313	ASSERT_VI_LOCKED(vp, __func__);
314	return (vp->v_rdev->si_usecount);
315}
316
317int
318devfs_usecount(struct vnode *vp)
319{
320	int count;
321
322	VNPASS(vp->v_type == VCHR, vp);
323	mtx_lock(&devfs_de_interlock);
324	VI_LOCK(vp);
325	count = devfs_usecountl(vp);
326	VI_UNLOCK(vp);
327	mtx_unlock(&devfs_de_interlock);
328	return (count);
329}
330
331void
332devfs_ctty_ref(struct vnode *vp)
333{
334
335	vrefact(vp);
336	devfs_usecount_add(vp);
337}
338
339void
340devfs_ctty_unref(struct vnode *vp)
341{
342
343	devfs_usecount_sub(vp);
344	vrele(vp);
345}
346
347/*
348 * On success devfs_populate_vp() returns with dmp->dm_lock held.
349 */
350static int
351devfs_populate_vp(struct vnode *vp)
352{
353	struct devfs_dirent *de;
354	struct devfs_mount *dmp;
355	int locked;
356
357	ASSERT_VOP_LOCKED(vp, "devfs_populate_vp");
358
359	dmp = VFSTODEVFS(vp->v_mount);
360	if (!devfs_populate_needed(dmp)) {
361		sx_xlock(&dmp->dm_lock);
362		goto out_nopopulate;
363	}
364
365	locked = VOP_ISLOCKED(vp);
366
367	sx_xlock(&dmp->dm_lock);
368	DEVFS_DMP_HOLD(dmp);
369
370	/* Can't call devfs_populate() with the vnode lock held. */
371	VOP_UNLOCK(vp);
372	devfs_populate(dmp);
373
374	sx_xunlock(&dmp->dm_lock);
375	vn_lock(vp, locked | LK_RETRY);
376	sx_xlock(&dmp->dm_lock);
377	if (DEVFS_DMP_DROP(dmp)) {
378		sx_xunlock(&dmp->dm_lock);
379		devfs_unmount_final(dmp);
380		return (ERESTART);
381	}
382out_nopopulate:
383	if (VN_IS_DOOMED(vp)) {
384		sx_xunlock(&dmp->dm_lock);
385		return (ERESTART);
386	}
387	de = vp->v_data;
388	KASSERT(de != NULL,
389	    ("devfs_populate_vp: vp->v_data == NULL but vnode not doomed"));
390	if ((de->de_flags & DE_DOOMED) != 0) {
391		sx_xunlock(&dmp->dm_lock);
392		return (ERESTART);
393	}
394
395	return (0);
396}
397
398static int
399devfs_vptocnp(struct vop_vptocnp_args *ap)
400{
401	struct vnode *vp = ap->a_vp;
402	struct vnode **dvp = ap->a_vpp;
403	struct devfs_mount *dmp;
404	char *buf = ap->a_buf;
405	size_t *buflen = ap->a_buflen;
406	struct devfs_dirent *dd, *de;
407	int i, error;
408
409	dmp = VFSTODEVFS(vp->v_mount);
410
411	error = devfs_populate_vp(vp);
412	if (error != 0)
413		return (error);
414
415	if (vp->v_type != VCHR && vp->v_type != VDIR) {
416		error = ENOENT;
417		goto finished;
418	}
419
420	dd = vp->v_data;
421	if (vp->v_type == VDIR && dd == dmp->dm_rootdir) {
422		*dvp = vp;
423		vref(*dvp);
424		goto finished;
425	}
426
427	i = *buflen;
428	i -= dd->de_dirent->d_namlen;
429	if (i < 0) {
430		error = ENOMEM;
431		goto finished;
432	}
433	bcopy(dd->de_dirent->d_name, buf + i, dd->de_dirent->d_namlen);
434	*buflen = i;
435	de = devfs_parent_dirent(dd);
436	if (de == NULL) {
437		error = ENOENT;
438		goto finished;
439	}
440	mtx_lock(&devfs_de_interlock);
441	*dvp = de->de_vnode;
442	if (*dvp != NULL) {
443		VI_LOCK(*dvp);
444		mtx_unlock(&devfs_de_interlock);
445		vholdl(*dvp);
446		VI_UNLOCK(*dvp);
447		vref(*dvp);
448		vdrop(*dvp);
449	} else {
450		mtx_unlock(&devfs_de_interlock);
451		error = ENOENT;
452	}
453finished:
454	sx_xunlock(&dmp->dm_lock);
455	return (error);
456}
457
458/*
459 * Construct the fully qualified path name relative to the mountpoint.
460 * If a NULL cnp is provided, no '/' is appended to the resulting path.
461 */
462char *
463devfs_fqpn(char *buf, struct devfs_mount *dmp, struct devfs_dirent *dd,
464    struct componentname *cnp)
465{
466	int i;
467	struct devfs_dirent *de;
468
469	sx_assert(&dmp->dm_lock, SA_LOCKED);
470
471	i = SPECNAMELEN;
472	buf[i] = '\0';
473	if (cnp != NULL)
474		i -= cnp->cn_namelen;
475	if (i < 0)
476		 return (NULL);
477	if (cnp != NULL)
478		bcopy(cnp->cn_nameptr, buf + i, cnp->cn_namelen);
479	de = dd;
480	while (de != dmp->dm_rootdir) {
481		if (cnp != NULL || i < SPECNAMELEN) {
482			i--;
483			if (i < 0)
484				 return (NULL);
485			buf[i] = '/';
486		}
487		i -= de->de_dirent->d_namlen;
488		if (i < 0)
489			 return (NULL);
490		bcopy(de->de_dirent->d_name, buf + i,
491		    de->de_dirent->d_namlen);
492		de = devfs_parent_dirent(de);
493		if (de == NULL)
494			return (NULL);
495	}
496	return (buf + i);
497}
498
499static int
500devfs_allocv_drop_refs(int drop_dm_lock, struct devfs_mount *dmp,
501	struct devfs_dirent *de)
502{
503	int not_found;
504
505	not_found = 0;
506	if (de->de_flags & DE_DOOMED)
507		not_found = 1;
508	if (DEVFS_DE_DROP(de)) {
509		KASSERT(not_found == 1, ("DEVFS de dropped but not doomed"));
510		devfs_dirent_free(de);
511	}
512	if (DEVFS_DMP_DROP(dmp)) {
513		KASSERT(not_found == 1,
514			("DEVFS mount struct freed before dirent"));
515		not_found = 2;
516		sx_xunlock(&dmp->dm_lock);
517		devfs_unmount_final(dmp);
518	}
519	if (not_found == 1 || (drop_dm_lock && not_found != 2))
520		sx_unlock(&dmp->dm_lock);
521	return (not_found);
522}
523
524/*
525 * devfs_allocv shall be entered with dmp->dm_lock held, and it drops
526 * it on return.
527 */
528int
529devfs_allocv(struct devfs_dirent *de, struct mount *mp, int lockmode,
530    struct vnode **vpp)
531{
532	int error;
533	struct vnode *vp;
534	struct cdev *dev;
535	struct devfs_mount *dmp;
536	struct cdevsw *dsw;
537	enum vgetstate vs;
538
539	dmp = VFSTODEVFS(mp);
540	if (de->de_flags & DE_DOOMED) {
541		sx_xunlock(&dmp->dm_lock);
542		return (ENOENT);
543	}
544loop:
545	DEVFS_DE_HOLD(de);
546	DEVFS_DMP_HOLD(dmp);
547	mtx_lock(&devfs_de_interlock);
548	vp = de->de_vnode;
549	if (vp != NULL) {
550		vs = vget_prep(vp);
551		mtx_unlock(&devfs_de_interlock);
552		sx_xunlock(&dmp->dm_lock);
553		vget_finish(vp, lockmode | LK_RETRY, vs);
554		sx_xlock(&dmp->dm_lock);
555		if (devfs_allocv_drop_refs(0, dmp, de)) {
556			vput(vp);
557			return (ENOENT);
558		} else if (VN_IS_DOOMED(vp)) {
559			mtx_lock(&devfs_de_interlock);
560			if (de->de_vnode == vp) {
561				de->de_vnode = NULL;
562				vp->v_data = NULL;
563			}
564			mtx_unlock(&devfs_de_interlock);
565			vput(vp);
566			goto loop;
567		}
568		sx_xunlock(&dmp->dm_lock);
569		*vpp = vp;
570		return (0);
571	}
572	mtx_unlock(&devfs_de_interlock);
573	if (de->de_dirent->d_type == DT_CHR) {
574		if (!(de->de_cdp->cdp_flags & CDP_ACTIVE)) {
575			devfs_allocv_drop_refs(1, dmp, de);
576			return (ENOENT);
577		}
578		dev = &de->de_cdp->cdp_c;
579	} else {
580		dev = NULL;
581	}
582	error = getnewvnode("devfs", mp, &devfs_vnodeops, &vp);
583	if (error != 0) {
584		devfs_allocv_drop_refs(1, dmp, de);
585		printf("devfs_allocv: failed to allocate new vnode\n");
586		return (error);
587	}
588
589	if (de->de_dirent->d_type == DT_CHR) {
590		vp->v_type = VCHR;
591		VI_LOCK(vp);
592		dev_lock();
593		dev_refl(dev);
594		/* XXX: v_rdev should be protect by vnode lock */
595		vp->v_rdev = dev;
596		VNPASS(vp->v_usecount == 1, vp);
597		/* Special casing of ttys for deadfs.  Probably redundant. */
598		dsw = dev->si_devsw;
599		if (dsw != NULL && (dsw->d_flags & D_TTY) != 0)
600			vp->v_vflag |= VV_ISTTY;
601		dev_unlock();
602		VI_UNLOCK(vp);
603		if ((dev->si_flags & SI_ETERNAL) != 0)
604			vp->v_vflag |= VV_ETERNALDEV;
605		vp->v_op = &devfs_specops;
606	} else if (de->de_dirent->d_type == DT_DIR) {
607		vp->v_type = VDIR;
608	} else if (de->de_dirent->d_type == DT_LNK) {
609		vp->v_type = VLNK;
610	} else {
611		vp->v_type = VBAD;
612	}
613	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_NOWITNESS);
614	VN_LOCK_ASHARE(vp);
615	mtx_lock(&devfs_de_interlock);
616	vp->v_data = de;
617	de->de_vnode = vp;
618	mtx_unlock(&devfs_de_interlock);
619	error = insmntque1(vp, mp);
620	if (error != 0) {
621		mtx_lock(&devfs_de_interlock);
622		vp->v_data = NULL;
623		de->de_vnode = NULL;
624		mtx_unlock(&devfs_de_interlock);
625		vgone(vp);
626		vput(vp);
627		(void) devfs_allocv_drop_refs(1, dmp, de);
628		return (error);
629	}
630	if (devfs_allocv_drop_refs(0, dmp, de)) {
631		vgone(vp);
632		vput(vp);
633		return (ENOENT);
634	}
635#ifdef MAC
636	mac_devfs_vnode_associate(mp, de, vp);
637#endif
638	sx_xunlock(&dmp->dm_lock);
639	vn_set_state(vp, VSTATE_CONSTRUCTED);
640	*vpp = vp;
641	return (0);
642}
643
644static int
645devfs_access(struct vop_access_args *ap)
646{
647	struct vnode *vp = ap->a_vp;
648	struct devfs_dirent *de;
649	struct proc *p;
650	int error;
651
652	de = vp->v_data;
653	if (vp->v_type == VDIR)
654		de = de->de_dir;
655
656	error = vaccess(vp->v_type, de->de_mode, de->de_uid, de->de_gid,
657	    ap->a_accmode, ap->a_cred);
658	if (error == 0)
659		return (0);
660	if (error != EACCES)
661		return (error);
662	p = ap->a_td->td_proc;
663	/* We do, however, allow access to the controlling terminal */
664	PROC_LOCK(p);
665	if (!(p->p_flag & P_CONTROLT)) {
666		PROC_UNLOCK(p);
667		return (error);
668	}
669	if (p->p_session->s_ttydp == de->de_cdp)
670		error = 0;
671	PROC_UNLOCK(p);
672	return (error);
673}
674
675_Static_assert(((FMASK | FCNTLFLAGS) & (FLASTCLOSE | FREVOKE)) == 0,
676    "devfs-only flag reuse failed");
677
678static int
679devfs_close(struct vop_close_args *ap)
680{
681	struct vnode *vp = ap->a_vp, *oldvp;
682	struct thread *td = ap->a_td;
683	struct proc *p;
684	struct cdev *dev = vp->v_rdev;
685	struct cdevsw *dsw;
686	struct devfs_dirent *de = vp->v_data;
687	int dflags, error, ref, vp_locked;
688
689	/*
690	 * XXX: Don't call d_close() if we were called because of
691	 * XXX: insmntque() failure.
692	 */
693	if (vp->v_data == NULL)
694		return (0);
695
696	/*
697	 * Hack: a tty device that is a controlling terminal
698	 * has a reference from the session structure.
699	 * We cannot easily tell that a character device is
700	 * a controlling terminal, unless it is the closing
701	 * process' controlling terminal.  In that case,
702	 * if the reference count is 2 (this last descriptor
703	 * plus the session), release the reference from the session.
704	 */
705	if (de->de_usecount == 2 && td != NULL) {
706		p = td->td_proc;
707		PROC_LOCK(p);
708		if (vp == p->p_session->s_ttyvp) {
709			PROC_UNLOCK(p);
710			oldvp = NULL;
711			sx_xlock(&proctree_lock);
712			if (vp == p->p_session->s_ttyvp) {
713				SESS_LOCK(p->p_session);
714				mtx_lock(&devfs_de_interlock);
715				VI_LOCK(vp);
716				if (devfs_usecountl(vp) == 2 && !VN_IS_DOOMED(vp)) {
717					p->p_session->s_ttyvp = NULL;
718					p->p_session->s_ttydp = NULL;
719					oldvp = vp;
720				}
721				VI_UNLOCK(vp);
722				mtx_unlock(&devfs_de_interlock);
723				SESS_UNLOCK(p->p_session);
724			}
725			sx_xunlock(&proctree_lock);
726			if (oldvp != NULL)
727				devfs_ctty_unref(oldvp);
728		} else
729			PROC_UNLOCK(p);
730	}
731	/*
732	 * We do not want to really close the device if it
733	 * is still in use unless we are trying to close it
734	 * forcibly. Since every use (buffer, vnode, swap, cmap)
735	 * holds a reference to the vnode, and because we mark
736	 * any other vnodes that alias this device, when the
737	 * sum of the reference counts on all the aliased
738	 * vnodes descends to one, we are on last close.
739	 */
740	dsw = dev_refthread(dev, &ref);
741	if (dsw == NULL)
742		return (ENXIO);
743	dflags = 0;
744	mtx_lock(&devfs_de_interlock);
745	VI_LOCK(vp);
746	if (devfs_usecountl(vp) == 1)
747		dflags |= FLASTCLOSE;
748	devfs_usecount_subl(vp);
749	mtx_unlock(&devfs_de_interlock);
750	if (VN_IS_DOOMED(vp)) {
751		/* Forced close. */
752		dflags |= FREVOKE | FNONBLOCK;
753	} else if (dsw->d_flags & D_TRACKCLOSE) {
754		/* Keep device updated on status. */
755	} else if ((dflags & FLASTCLOSE) == 0) {
756		VI_UNLOCK(vp);
757		dev_relthread(dev, ref);
758		return (0);
759	}
760	vholdnz(vp);
761	VI_UNLOCK(vp);
762	vp_locked = VOP_ISLOCKED(vp);
763	VOP_UNLOCK(vp);
764	KASSERT(dev->si_refcount > 0,
765	    ("devfs_close() on un-referenced struct cdev *(%s)", devtoname(dev)));
766	error = dsw->d_close(dev, ap->a_fflag | dflags, S_IFCHR, td);
767	dev_relthread(dev, ref);
768	vn_lock(vp, vp_locked | LK_RETRY);
769	vdrop(vp);
770	return (error);
771}
772
773static int
774devfs_close_f(struct file *fp, struct thread *td)
775{
776	int error;
777	struct file *fpop;
778
779	/*
780	 * NB: td may be NULL if this descriptor is closed due to
781	 * garbage collection from a closed UNIX domain socket.
782	 */
783	fpop = curthread->td_fpop;
784	curthread->td_fpop = fp;
785	error = vnops.fo_close(fp, td);
786	curthread->td_fpop = fpop;
787
788	/*
789	 * The f_cdevpriv cannot be assigned non-NULL value while we
790	 * are destroying the file.
791	 */
792	if (fp->f_cdevpriv != NULL)
793		devfs_fpdrop(fp);
794	return (error);
795}
796
797static int
798devfs_getattr(struct vop_getattr_args *ap)
799{
800	struct vnode *vp = ap->a_vp;
801	struct vattr *vap = ap->a_vap;
802	struct devfs_dirent *de;
803	struct devfs_mount *dmp;
804	struct cdev *dev;
805	struct timeval boottime;
806	int error;
807
808	error = devfs_populate_vp(vp);
809	if (error != 0)
810		return (error);
811
812	dmp = VFSTODEVFS(vp->v_mount);
813	sx_xunlock(&dmp->dm_lock);
814
815	de = vp->v_data;
816	KASSERT(de != NULL, ("Null dirent in devfs_getattr vp=%p", vp));
817	if (vp->v_type == VDIR) {
818		de = de->de_dir;
819		KASSERT(de != NULL,
820		    ("Null dir dirent in devfs_getattr vp=%p", vp));
821	}
822	vap->va_uid = de->de_uid;
823	vap->va_gid = de->de_gid;
824	vap->va_mode = de->de_mode;
825	if (vp->v_type == VLNK)
826		vap->va_size = strlen(de->de_symlink);
827	else if (vp->v_type == VDIR)
828		vap->va_size = vap->va_bytes = DEV_BSIZE;
829	else
830		vap->va_size = 0;
831	if (vp->v_type != VDIR)
832		vap->va_bytes = 0;
833	vap->va_blocksize = DEV_BSIZE;
834	vap->va_type = vp->v_type;
835
836	getboottime(&boottime);
837#define fix(aa)							\
838	do {							\
839		if ((aa).tv_sec <= 3600) {			\
840			(aa).tv_sec = boottime.tv_sec;		\
841			(aa).tv_nsec = boottime.tv_usec * 1000; \
842		}						\
843	} while (0)
844
845	if (vp->v_type != VCHR)  {
846		fix(de->de_atime);
847		vap->va_atime = de->de_atime;
848		fix(de->de_mtime);
849		vap->va_mtime = de->de_mtime;
850		fix(de->de_ctime);
851		vap->va_ctime = de->de_ctime;
852	} else {
853		dev = vp->v_rdev;
854		fix(dev->si_atime);
855		vap->va_atime = dev->si_atime;
856		fix(dev->si_mtime);
857		vap->va_mtime = dev->si_mtime;
858		fix(dev->si_ctime);
859		vap->va_ctime = dev->si_ctime;
860
861		vap->va_rdev = cdev2priv(dev)->cdp_inode;
862	}
863	vap->va_gen = 0;
864	vap->va_flags = 0;
865	vap->va_filerev = 0;
866	vap->va_nlink = de->de_links;
867	vap->va_fileid = de->de_inode;
868
869	return (error);
870}
871
872/* ARGSUSED */
873static int
874devfs_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred, struct thread *td)
875{
876	struct file *fpop;
877	int error;
878
879	fpop = td->td_fpop;
880	td->td_fpop = fp;
881	error = vnops.fo_ioctl(fp, com, data, cred, td);
882	td->td_fpop = fpop;
883	return (error);
884}
885
886void *
887fiodgname_buf_get_ptr(void *fgnp, u_long com)
888{
889	union {
890		struct fiodgname_arg	fgn;
891#ifdef COMPAT_FREEBSD32
892		struct fiodgname_arg32	fgn32;
893#endif
894	} *fgnup;
895
896	fgnup = fgnp;
897	switch (com) {
898	case FIODGNAME:
899		return (fgnup->fgn.buf);
900#ifdef COMPAT_FREEBSD32
901	case FIODGNAME_32:
902		return ((void *)(uintptr_t)fgnup->fgn32.buf);
903#endif
904	default:
905		panic("Unhandled ioctl command %ld", com);
906	}
907}
908
909static int
910devfs_ioctl(struct vop_ioctl_args *ap)
911{
912	struct fiodgname_arg *fgn;
913	struct vnode *vpold, *vp;
914	struct cdevsw *dsw;
915	struct thread *td;
916	struct session *sess;
917	struct cdev *dev;
918	int error, ref, i;
919	const char *p;
920	u_long com;
921
922	vp = ap->a_vp;
923	com = ap->a_command;
924	td = ap->a_td;
925
926	dsw = devvn_refthread(vp, &dev, &ref);
927	if (dsw == NULL)
928		return (ENXIO);
929	KASSERT(dev->si_refcount > 0,
930	    ("devfs: un-referenced struct cdev *(%s)", devtoname(dev)));
931
932	switch (com) {
933	case FIODTYPE:
934		*(int *)ap->a_data = dsw->d_flags & D_TYPEMASK;
935		error = 0;
936		break;
937	case FIODGNAME:
938#ifdef	COMPAT_FREEBSD32
939	case FIODGNAME_32:
940#endif
941		fgn = ap->a_data;
942		p = devtoname(dev);
943		i = strlen(p) + 1;
944		if (i > fgn->len)
945			error = EINVAL;
946		else
947			error = copyout(p, fiodgname_buf_get_ptr(fgn, com), i);
948		break;
949	default:
950		error = dsw->d_ioctl(dev, com, ap->a_data, ap->a_fflag, td);
951	}
952
953	dev_relthread(dev, ref);
954	if (error == ENOIOCTL)
955		error = ENOTTY;
956
957	if (error == 0 && com == TIOCSCTTY) {
958		/*
959		 * Do nothing if reassigning same control tty, or if the
960		 * control tty has already disappeared.  If it disappeared,
961		 * it's because we were racing with TIOCNOTTY.  TIOCNOTTY
962		 * already took care of releasing the old vnode and we have
963		 * nothing left to do.
964		 */
965		sx_slock(&proctree_lock);
966		sess = td->td_proc->p_session;
967		if (sess->s_ttyvp == vp || sess->s_ttyp == NULL) {
968			sx_sunlock(&proctree_lock);
969			return (0);
970		}
971
972		devfs_ctty_ref(vp);
973		SESS_LOCK(sess);
974		vpold = sess->s_ttyvp;
975		sess->s_ttyvp = vp;
976		sess->s_ttydp = cdev2priv(dev);
977		SESS_UNLOCK(sess);
978
979		sx_sunlock(&proctree_lock);
980
981		/* Get rid of reference to old control tty */
982		if (vpold)
983			devfs_ctty_unref(vpold);
984	}
985	return (error);
986}
987
988/* ARGSUSED */
989static int
990devfs_kqfilter_f(struct file *fp, struct knote *kn)
991{
992	struct cdev *dev;
993	struct cdevsw *dsw;
994	int error, ref;
995	struct file *fpop;
996	struct thread *td;
997
998	td = curthread;
999	fpop = td->td_fpop;
1000	error = devfs_fp_check(fp, &dev, &dsw, &ref);
1001	if (error)
1002		return (error);
1003	error = dsw->d_kqfilter(dev, kn);
1004	td->td_fpop = fpop;
1005	dev_relthread(dev, ref);
1006	return (error);
1007}
1008
1009static inline int
1010devfs_prison_check(struct devfs_dirent *de, struct thread *td)
1011{
1012	struct cdev_priv *cdp;
1013	struct ucred *dcr;
1014	struct proc *p;
1015	int error;
1016
1017	cdp = de->de_cdp;
1018	if (cdp == NULL)
1019		return (0);
1020	dcr = cdp->cdp_c.si_cred;
1021	if (dcr == NULL)
1022		return (0);
1023
1024	error = prison_check(td->td_ucred, dcr);
1025	if (error == 0)
1026		return (0);
1027	/* We do, however, allow access to the controlling terminal */
1028	p = td->td_proc;
1029	PROC_LOCK(p);
1030	if (!(p->p_flag & P_CONTROLT)) {
1031		PROC_UNLOCK(p);
1032		return (error);
1033	}
1034	if (p->p_session->s_ttydp == cdp)
1035		error = 0;
1036	PROC_UNLOCK(p);
1037	return (error);
1038}
1039
1040static int
1041devfs_lookupx(struct vop_lookup_args *ap, int *dm_unlock)
1042{
1043	struct componentname *cnp;
1044	struct vnode *dvp, **vpp;
1045	struct thread *td;
1046	struct devfs_dirent *de, *dd;
1047	struct devfs_dirent **dde;
1048	struct devfs_mount *dmp;
1049	struct mount *mp;
1050	struct cdev *cdev;
1051	int error, flags, nameiop, dvplocked;
1052	char specname[SPECNAMELEN + 1], *pname;
1053
1054	td = curthread;
1055	cnp = ap->a_cnp;
1056	vpp = ap->a_vpp;
1057	dvp = ap->a_dvp;
1058	pname = cnp->cn_nameptr;
1059	flags = cnp->cn_flags;
1060	nameiop = cnp->cn_nameiop;
1061	mp = dvp->v_mount;
1062	dmp = VFSTODEVFS(mp);
1063	dd = dvp->v_data;
1064	*vpp = NULLVP;
1065
1066	if ((flags & ISLASTCN) && nameiop == RENAME)
1067		return (EOPNOTSUPP);
1068
1069	if (dvp->v_type != VDIR)
1070		return (ENOTDIR);
1071
1072	if ((flags & ISDOTDOT) && (dvp->v_vflag & VV_ROOT))
1073		return (EIO);
1074
1075	error = vn_dir_check_exec(dvp, cnp);
1076	if (error != 0)
1077		return (error);
1078
1079	if (cnp->cn_namelen == 1 && *pname == '.') {
1080		if ((flags & ISLASTCN) && nameiop != LOOKUP)
1081			return (EINVAL);
1082		*vpp = dvp;
1083		VREF(dvp);
1084		return (0);
1085	}
1086
1087	if (flags & ISDOTDOT) {
1088		if ((flags & ISLASTCN) && nameiop != LOOKUP)
1089			return (EINVAL);
1090		de = devfs_parent_dirent(dd);
1091		if (de == NULL)
1092			return (ENOENT);
1093		dvplocked = VOP_ISLOCKED(dvp);
1094		VOP_UNLOCK(dvp);
1095		error = devfs_allocv(de, mp, cnp->cn_lkflags & LK_TYPE_MASK,
1096		    vpp);
1097		*dm_unlock = 0;
1098		vn_lock(dvp, dvplocked | LK_RETRY);
1099		return (error);
1100	}
1101
1102	dd = dvp->v_data;
1103	de = devfs_find(dd, cnp->cn_nameptr, cnp->cn_namelen, 0);
1104	while (de == NULL) {	/* While(...) so we can use break */
1105
1106		if (nameiop == DELETE)
1107			return (ENOENT);
1108
1109		/*
1110		 * OK, we didn't have an entry for the name we were asked for
1111		 * so we try to see if anybody can create it on demand.
1112		 */
1113		pname = devfs_fqpn(specname, dmp, dd, cnp);
1114		if (pname == NULL)
1115			break;
1116
1117		cdev = NULL;
1118		DEVFS_DMP_HOLD(dmp);
1119		sx_xunlock(&dmp->dm_lock);
1120		EVENTHANDLER_INVOKE(dev_clone,
1121		    td->td_ucred, pname, strlen(pname), &cdev);
1122
1123		if (cdev == NULL)
1124			sx_xlock(&dmp->dm_lock);
1125		else if (devfs_populate_vp(dvp) != 0) {
1126			*dm_unlock = 0;
1127			sx_xlock(&dmp->dm_lock);
1128			if (DEVFS_DMP_DROP(dmp)) {
1129				sx_xunlock(&dmp->dm_lock);
1130				devfs_unmount_final(dmp);
1131			} else
1132				sx_xunlock(&dmp->dm_lock);
1133			dev_rel(cdev);
1134			return (ENOENT);
1135		}
1136		if (DEVFS_DMP_DROP(dmp)) {
1137			*dm_unlock = 0;
1138			sx_xunlock(&dmp->dm_lock);
1139			devfs_unmount_final(dmp);
1140			if (cdev != NULL)
1141				dev_rel(cdev);
1142			return (ENOENT);
1143		}
1144
1145		if (cdev == NULL)
1146			break;
1147
1148		dev_lock();
1149		dde = &cdev2priv(cdev)->cdp_dirents[dmp->dm_idx];
1150		if (dde != NULL && *dde != NULL)
1151			de = *dde;
1152		dev_unlock();
1153		dev_rel(cdev);
1154		break;
1155	}
1156
1157	if (de == NULL || de->de_flags & DE_WHITEOUT) {
1158		if ((nameiop == CREATE || nameiop == RENAME) &&
1159		    (flags & (LOCKPARENT | WANTPARENT)) && (flags & ISLASTCN)) {
1160			return (EJUSTRETURN);
1161		}
1162		return (ENOENT);
1163	}
1164
1165	if (devfs_prison_check(de, td))
1166		return (ENOENT);
1167
1168	if ((cnp->cn_nameiop == DELETE) && (flags & ISLASTCN)) {
1169		error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td);
1170		if (error)
1171			return (error);
1172		if (*vpp == dvp) {
1173			VREF(dvp);
1174			*vpp = dvp;
1175			return (0);
1176		}
1177	}
1178	error = devfs_allocv(de, mp, cnp->cn_lkflags & LK_TYPE_MASK, vpp);
1179	*dm_unlock = 0;
1180	return (error);
1181}
1182
1183static int
1184devfs_lookup(struct vop_lookup_args *ap)
1185{
1186	int j;
1187	struct devfs_mount *dmp;
1188	int dm_unlock;
1189
1190	if (devfs_populate_vp(ap->a_dvp) != 0)
1191		return (ENOTDIR);
1192
1193	dmp = VFSTODEVFS(ap->a_dvp->v_mount);
1194	dm_unlock = 1;
1195	j = devfs_lookupx(ap, &dm_unlock);
1196	if (dm_unlock == 1)
1197		sx_xunlock(&dmp->dm_lock);
1198	return (j);
1199}
1200
1201static int
1202devfs_mknod(struct vop_mknod_args *ap)
1203{
1204	struct componentname *cnp;
1205	struct vnode *dvp, **vpp;
1206	struct devfs_dirent *dd, *de;
1207	struct devfs_mount *dmp;
1208	int error;
1209
1210	/*
1211	 * The only type of node we should be creating here is a
1212	 * character device, for anything else return EOPNOTSUPP.
1213	 */
1214	if (ap->a_vap->va_type != VCHR)
1215		return (EOPNOTSUPP);
1216	dvp = ap->a_dvp;
1217	dmp = VFSTODEVFS(dvp->v_mount);
1218
1219	cnp = ap->a_cnp;
1220	vpp = ap->a_vpp;
1221	dd = dvp->v_data;
1222
1223	error = ENOENT;
1224	sx_xlock(&dmp->dm_lock);
1225	TAILQ_FOREACH(de, &dd->de_dlist, de_list) {
1226		if (cnp->cn_namelen != de->de_dirent->d_namlen)
1227			continue;
1228		if (de->de_dirent->d_type == DT_CHR &&
1229		    (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0)
1230			continue;
1231		if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name,
1232		    de->de_dirent->d_namlen) != 0)
1233			continue;
1234		if (de->de_flags & DE_WHITEOUT)
1235			break;
1236		goto notfound;
1237	}
1238	if (de == NULL)
1239		goto notfound;
1240	de->de_flags &= ~DE_WHITEOUT;
1241	error = devfs_allocv(de, dvp->v_mount, LK_EXCLUSIVE, vpp);
1242	return (error);
1243notfound:
1244	sx_xunlock(&dmp->dm_lock);
1245	return (error);
1246}
1247
1248/* ARGSUSED */
1249static int
1250devfs_open(struct vop_open_args *ap)
1251{
1252	struct thread *td = ap->a_td;
1253	struct vnode *vp = ap->a_vp;
1254	struct cdev *dev = vp->v_rdev;
1255	struct file *fp = ap->a_fp;
1256	int error, ref, vlocked;
1257	struct cdevsw *dsw;
1258	struct file *fpop;
1259
1260	if (vp->v_type == VBLK)
1261		return (ENXIO);
1262
1263	if (dev == NULL)
1264		return (ENXIO);
1265
1266	/* Make this field valid before any I/O in d_open. */
1267	if (dev->si_iosize_max == 0)
1268		dev->si_iosize_max = DFLTPHYS;
1269
1270	dsw = dev_refthread(dev, &ref);
1271	if (dsw == NULL)
1272		return (ENXIO);
1273	if (fp == NULL && dsw->d_fdopen != NULL) {
1274		dev_relthread(dev, ref);
1275		return (ENXIO);
1276	}
1277
1278	if (vp->v_type == VCHR)
1279		devfs_usecount_add(vp);
1280
1281	vlocked = VOP_ISLOCKED(vp);
1282	VOP_UNLOCK(vp);
1283
1284	fpop = td->td_fpop;
1285	td->td_fpop = fp;
1286	if (fp != NULL) {
1287		fp->f_data = dev;
1288		fp->f_vnode = vp;
1289	}
1290	if (dsw->d_fdopen != NULL)
1291		error = dsw->d_fdopen(dev, ap->a_mode, td, fp);
1292	else
1293		error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td);
1294	/* Clean up any cdevpriv upon error. */
1295	if (error != 0)
1296		devfs_clear_cdevpriv();
1297	td->td_fpop = fpop;
1298
1299	vn_lock(vp, vlocked | LK_RETRY);
1300	if (error != 0 && vp->v_type == VCHR)
1301		devfs_usecount_sub(vp);
1302
1303	dev_relthread(dev, ref);
1304	if (error != 0) {
1305		if (error == ERESTART)
1306			error = EINTR;
1307		return (error);
1308	}
1309
1310#if 0	/* /dev/console */
1311	KASSERT(fp != NULL, ("Could not vnode bypass device on NULL fp"));
1312#else
1313	if (fp == NULL)
1314		return (error);
1315#endif
1316	if (fp->f_ops == &badfileops)
1317		finit(fp, fp->f_flag, DTYPE_VNODE, dev, &devfs_ops_f);
1318	return (error);
1319}
1320
1321static int
1322devfs_pathconf(struct vop_pathconf_args *ap)
1323{
1324
1325	switch (ap->a_name) {
1326	case _PC_FILESIZEBITS:
1327		*ap->a_retval = 64;
1328		return (0);
1329	case _PC_NAME_MAX:
1330		*ap->a_retval = NAME_MAX;
1331		return (0);
1332	case _PC_LINK_MAX:
1333		*ap->a_retval = INT_MAX;
1334		return (0);
1335	case _PC_SYMLINK_MAX:
1336		*ap->a_retval = MAXPATHLEN;
1337		return (0);
1338	case _PC_MAX_CANON:
1339		if (ap->a_vp->v_vflag & VV_ISTTY) {
1340			*ap->a_retval = MAX_CANON;
1341			return (0);
1342		}
1343		return (EINVAL);
1344	case _PC_MAX_INPUT:
1345		if (ap->a_vp->v_vflag & VV_ISTTY) {
1346			*ap->a_retval = MAX_INPUT;
1347			return (0);
1348		}
1349		return (EINVAL);
1350	case _PC_VDISABLE:
1351		if (ap->a_vp->v_vflag & VV_ISTTY) {
1352			*ap->a_retval = _POSIX_VDISABLE;
1353			return (0);
1354		}
1355		return (EINVAL);
1356	case _PC_MAC_PRESENT:
1357#ifdef MAC
1358		/*
1359		 * If MAC is enabled, devfs automatically supports
1360		 * trivial non-persistent label storage.
1361		 */
1362		*ap->a_retval = 1;
1363#else
1364		*ap->a_retval = 0;
1365#endif
1366		return (0);
1367	case _PC_CHOWN_RESTRICTED:
1368		*ap->a_retval = 1;
1369		return (0);
1370	default:
1371		return (vop_stdpathconf(ap));
1372	}
1373	/* NOTREACHED */
1374}
1375
1376/* ARGSUSED */
1377static int
1378devfs_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td)
1379{
1380	struct cdev *dev;
1381	struct cdevsw *dsw;
1382	int error, ref;
1383	struct file *fpop;
1384
1385	fpop = td->td_fpop;
1386	error = devfs_fp_check(fp, &dev, &dsw, &ref);
1387	if (error != 0) {
1388		error = vnops.fo_poll(fp, events, cred, td);
1389		return (error);
1390	}
1391	error = dsw->d_poll(dev, events, td);
1392	td->td_fpop = fpop;
1393	dev_relthread(dev, ref);
1394	return(error);
1395}
1396
1397/*
1398 * Print out the contents of a special device vnode.
1399 */
1400static int
1401devfs_print(struct vop_print_args *ap)
1402{
1403
1404	printf("\tdev %s\n", devtoname(ap->a_vp->v_rdev));
1405	return (0);
1406}
1407
1408static int
1409devfs_read_f(struct file *fp, struct uio *uio, struct ucred *cred,
1410    int flags, struct thread *td)
1411{
1412	struct cdev *dev;
1413	int ioflag, error, ref;
1414	ssize_t resid;
1415	struct cdevsw *dsw;
1416	struct file *fpop;
1417
1418	if (uio->uio_resid > DEVFS_IOSIZE_MAX)
1419		return (EINVAL);
1420	fpop = td->td_fpop;
1421	error = devfs_fp_check(fp, &dev, &dsw, &ref);
1422	if (error != 0) {
1423		error = vnops.fo_read(fp, uio, cred, flags, td);
1424		return (error);
1425	}
1426	resid = uio->uio_resid;
1427	ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT);
1428	if (ioflag & O_DIRECT)
1429		ioflag |= IO_DIRECT;
1430
1431	foffset_lock_uio(fp, uio, flags | FOF_NOLOCK);
1432	error = dsw->d_read(dev, uio, ioflag);
1433	if (uio->uio_resid != resid || (error == 0 && resid != 0))
1434		devfs_timestamp(&dev->si_atime);
1435	td->td_fpop = fpop;
1436	dev_relthread(dev, ref);
1437
1438	foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF_R);
1439	return (error);
1440}
1441
1442static int
1443devfs_readdir(struct vop_readdir_args *ap)
1444{
1445	int error;
1446	struct uio *uio;
1447	struct dirent *dp;
1448	struct devfs_dirent *dd;
1449	struct devfs_dirent *de;
1450	struct devfs_mount *dmp;
1451	off_t off;
1452	int *tmp_ncookies = NULL;
1453
1454	if (ap->a_vp->v_type != VDIR)
1455		return (ENOTDIR);
1456
1457	uio = ap->a_uio;
1458	if (uio->uio_offset < 0)
1459		return (EINVAL);
1460
1461	/*
1462	 * XXX: This is a temporary hack to get around this filesystem not
1463	 * supporting cookies. We store the location of the ncookies pointer
1464	 * in a temporary variable before calling vfs_subr.c:vfs_read_dirent()
1465	 * and set the number of cookies to 0. We then set the pointer to
1466	 * NULL so that vfs_read_dirent doesn't try to call realloc() on
1467	 * ap->a_cookies. Later in this function, we restore the ap->a_ncookies
1468	 * pointer to its original location before returning to the caller.
1469	 */
1470	if (ap->a_ncookies != NULL) {
1471		tmp_ncookies = ap->a_ncookies;
1472		*ap->a_ncookies = 0;
1473		ap->a_ncookies = NULL;
1474	}
1475
1476	dmp = VFSTODEVFS(ap->a_vp->v_mount);
1477	if (devfs_populate_vp(ap->a_vp) != 0) {
1478		if (tmp_ncookies != NULL)
1479			ap->a_ncookies = tmp_ncookies;
1480		return (EIO);
1481	}
1482	error = 0;
1483	de = ap->a_vp->v_data;
1484	off = 0;
1485	TAILQ_FOREACH(dd, &de->de_dlist, de_list) {
1486		KASSERT(dd->de_cdp != (void *)0xdeadc0de, ("%s %d\n", __func__, __LINE__));
1487		if (dd->de_flags & (DE_COVERED | DE_WHITEOUT))
1488			continue;
1489		if (devfs_prison_check(dd, uio->uio_td))
1490			continue;
1491		if (dd->de_dirent->d_type == DT_DIR)
1492			de = dd->de_dir;
1493		else
1494			de = dd;
1495		dp = dd->de_dirent;
1496		MPASS(dp->d_reclen == GENERIC_DIRSIZ(dp));
1497		if (dp->d_reclen > uio->uio_resid)
1498			break;
1499		dp->d_fileno = de->de_inode;
1500		/* NOTE: d_off is the offset for the *next* entry. */
1501		dp->d_off = off + dp->d_reclen;
1502		if (off >= uio->uio_offset) {
1503			error = vfs_read_dirent(ap, dp, off);
1504			if (error)
1505				break;
1506		}
1507		off += dp->d_reclen;
1508	}
1509	sx_xunlock(&dmp->dm_lock);
1510	uio->uio_offset = off;
1511
1512	/*
1513	 * Restore ap->a_ncookies if it wasn't originally NULL in the first
1514	 * place.
1515	 */
1516	if (tmp_ncookies != NULL)
1517		ap->a_ncookies = tmp_ncookies;
1518
1519	return (error);
1520}
1521
1522static int
1523devfs_readlink(struct vop_readlink_args *ap)
1524{
1525	struct devfs_dirent *de;
1526
1527	de = ap->a_vp->v_data;
1528	return (uiomove(de->de_symlink, strlen(de->de_symlink), ap->a_uio));
1529}
1530
1531static void
1532devfs_reclaiml(struct vnode *vp)
1533{
1534	struct devfs_dirent *de;
1535
1536	mtx_assert(&devfs_de_interlock, MA_OWNED);
1537	de = vp->v_data;
1538	if (de != NULL) {
1539		MPASS(de->de_usecount == 0);
1540		de->de_vnode = NULL;
1541		vp->v_data = NULL;
1542	}
1543}
1544
1545static int
1546devfs_reclaim(struct vop_reclaim_args *ap)
1547{
1548	struct vnode *vp;
1549
1550	vp = ap->a_vp;
1551	mtx_lock(&devfs_de_interlock);
1552	devfs_reclaiml(vp);
1553	mtx_unlock(&devfs_de_interlock);
1554	return (0);
1555}
1556
1557static int
1558devfs_reclaim_vchr(struct vop_reclaim_args *ap)
1559{
1560	struct vnode *vp;
1561	struct cdev *dev;
1562
1563	vp = ap->a_vp;
1564	MPASS(vp->v_type == VCHR);
1565
1566	mtx_lock(&devfs_de_interlock);
1567	VI_LOCK(vp);
1568	devfs_usecount_subl(vp);
1569	devfs_reclaiml(vp);
1570	mtx_unlock(&devfs_de_interlock);
1571	dev_lock();
1572	dev = vp->v_rdev;
1573	vp->v_rdev = NULL;
1574	dev_unlock();
1575	VI_UNLOCK(vp);
1576	if (dev != NULL)
1577		dev_rel(dev);
1578	return (0);
1579}
1580
1581static int
1582devfs_remove(struct vop_remove_args *ap)
1583{
1584	struct vnode *dvp = ap->a_dvp;
1585	struct vnode *vp = ap->a_vp;
1586	struct devfs_dirent *dd;
1587	struct devfs_dirent *de, *de_covered;
1588	struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount);
1589
1590	ASSERT_VOP_ELOCKED(dvp, "devfs_remove");
1591	ASSERT_VOP_ELOCKED(vp, "devfs_remove");
1592
1593	sx_xlock(&dmp->dm_lock);
1594	dd = ap->a_dvp->v_data;
1595	de = vp->v_data;
1596	if (de->de_cdp == NULL) {
1597		TAILQ_REMOVE(&dd->de_dlist, de, de_list);
1598		if (de->de_dirent->d_type == DT_LNK) {
1599			de_covered = devfs_find(dd, de->de_dirent->d_name,
1600			    de->de_dirent->d_namlen, 0);
1601			if (de_covered != NULL)
1602				de_covered->de_flags &= ~DE_COVERED;
1603		}
1604		/* We need to unlock dvp because devfs_delete() may lock it. */
1605		VOP_UNLOCK(vp);
1606		if (dvp != vp)
1607			VOP_UNLOCK(dvp);
1608		devfs_delete(dmp, de, 0);
1609		sx_xunlock(&dmp->dm_lock);
1610		if (dvp != vp)
1611			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
1612		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1613	} else {
1614		de->de_flags |= DE_WHITEOUT;
1615		sx_xunlock(&dmp->dm_lock);
1616	}
1617	return (0);
1618}
1619
1620/*
1621 * Revoke is called on a tty when a terminal session ends.  The vnode
1622 * is orphaned by setting v_op to deadfs so we need to let go of it
1623 * as well so that we create a new one next time around.
1624 *
1625 */
1626static int
1627devfs_revoke(struct vop_revoke_args *ap)
1628{
1629	struct vnode *vp = ap->a_vp, *vp2;
1630	struct cdev *dev;
1631	struct cdev_priv *cdp;
1632	struct devfs_dirent *de;
1633	enum vgetstate vs;
1634	u_int i;
1635
1636	KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL"));
1637
1638	dev = vp->v_rdev;
1639	cdp = cdev2priv(dev);
1640
1641	dev_lock();
1642	cdp->cdp_inuse++;
1643	dev_unlock();
1644
1645	vhold(vp);
1646	vgone(vp);
1647	vdrop(vp);
1648
1649	VOP_UNLOCK(vp);
1650 loop:
1651	for (;;) {
1652		mtx_lock(&devfs_de_interlock);
1653		dev_lock();
1654		vp2 = NULL;
1655		for (i = 0; i <= cdp->cdp_maxdirent; i++) {
1656			de = cdp->cdp_dirents[i];
1657			if (de == NULL)
1658				continue;
1659
1660			vp2 = de->de_vnode;
1661			if (vp2 != NULL) {
1662				dev_unlock();
1663				vs = vget_prep(vp2);
1664				mtx_unlock(&devfs_de_interlock);
1665				if (vget_finish(vp2, LK_EXCLUSIVE, vs) != 0)
1666					goto loop;
1667				vhold(vp2);
1668				vgone(vp2);
1669				vdrop(vp2);
1670				vput(vp2);
1671				break;
1672			}
1673		}
1674		if (vp2 != NULL) {
1675			continue;
1676		}
1677		dev_unlock();
1678		mtx_unlock(&devfs_de_interlock);
1679		break;
1680	}
1681	dev_lock();
1682	cdp->cdp_inuse--;
1683	if (!(cdp->cdp_flags & CDP_ACTIVE) && cdp->cdp_inuse == 0) {
1684		KASSERT((cdp->cdp_flags & CDP_ON_ACTIVE_LIST) != 0,
1685		    ("%s: cdp %p (%s) not on active list",
1686		    __func__, cdp, dev->si_name));
1687		cdp->cdp_flags &= ~CDP_ON_ACTIVE_LIST;
1688		TAILQ_REMOVE(&cdevp_list, cdp, cdp_list);
1689		dev_unlock();
1690		dev_rel(&cdp->cdp_c);
1691	} else
1692		dev_unlock();
1693
1694	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1695	return (0);
1696}
1697
1698static int
1699devfs_rioctl(struct vop_ioctl_args *ap)
1700{
1701	struct vnode *vp;
1702	struct devfs_mount *dmp;
1703	int error;
1704
1705	vp = ap->a_vp;
1706	vn_lock(vp, LK_SHARED | LK_RETRY);
1707	if (VN_IS_DOOMED(vp)) {
1708		VOP_UNLOCK(vp);
1709		return (EBADF);
1710	}
1711	dmp = VFSTODEVFS(vp->v_mount);
1712	sx_xlock(&dmp->dm_lock);
1713	VOP_UNLOCK(vp);
1714	DEVFS_DMP_HOLD(dmp);
1715	devfs_populate(dmp);
1716	if (DEVFS_DMP_DROP(dmp)) {
1717		sx_xunlock(&dmp->dm_lock);
1718		devfs_unmount_final(dmp);
1719		return (ENOENT);
1720	}
1721	error = devfs_rules_ioctl(dmp, ap->a_command, ap->a_data, ap->a_td);
1722	sx_xunlock(&dmp->dm_lock);
1723	return (error);
1724}
1725
1726static int
1727devfs_rread(struct vop_read_args *ap)
1728{
1729
1730	if (ap->a_vp->v_type != VDIR)
1731		return (EINVAL);
1732	return (VOP_READDIR(ap->a_vp, ap->a_uio, ap->a_cred, NULL, NULL, NULL));
1733}
1734
1735static int
1736devfs_setattr(struct vop_setattr_args *ap)
1737{
1738	struct devfs_dirent *de;
1739	struct vattr *vap;
1740	struct vnode *vp;
1741	struct thread *td;
1742	int c, error;
1743	uid_t uid;
1744	gid_t gid;
1745
1746	vap = ap->a_vap;
1747	vp = ap->a_vp;
1748	td = curthread;
1749	if ((vap->va_type != VNON) ||
1750	    (vap->va_nlink != VNOVAL) ||
1751	    (vap->va_fsid != VNOVAL) ||
1752	    (vap->va_fileid != VNOVAL) ||
1753	    (vap->va_blocksize != VNOVAL) ||
1754	    (vap->va_flags != VNOVAL && vap->va_flags != 0) ||
1755	    (vap->va_rdev != VNOVAL) ||
1756	    ((int)vap->va_bytes != VNOVAL) ||
1757	    (vap->va_gen != VNOVAL)) {
1758		return (EINVAL);
1759	}
1760
1761	error = devfs_populate_vp(vp);
1762	if (error != 0)
1763		return (error);
1764
1765	de = vp->v_data;
1766	if (vp->v_type == VDIR)
1767		de = de->de_dir;
1768
1769	c = 0;
1770	if (vap->va_uid == (uid_t)VNOVAL)
1771		uid = de->de_uid;
1772	else
1773		uid = vap->va_uid;
1774	if (vap->va_gid == (gid_t)VNOVAL)
1775		gid = de->de_gid;
1776	else
1777		gid = vap->va_gid;
1778	if (uid != de->de_uid || gid != de->de_gid) {
1779		if ((ap->a_cred->cr_uid != de->de_uid) || uid != de->de_uid ||
1780		    (gid != de->de_gid && !groupmember(gid, ap->a_cred))) {
1781			error = priv_check(td, PRIV_VFS_CHOWN);
1782			if (error != 0)
1783				goto ret;
1784		}
1785		de->de_uid = uid;
1786		de->de_gid = gid;
1787		c = 1;
1788	}
1789
1790	if (vap->va_mode != (mode_t)VNOVAL) {
1791		if (ap->a_cred->cr_uid != de->de_uid) {
1792			error = priv_check(td, PRIV_VFS_ADMIN);
1793			if (error != 0)
1794				goto ret;
1795		}
1796		de->de_mode = vap->va_mode;
1797		c = 1;
1798	}
1799
1800	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
1801		error = vn_utimes_perm(vp, vap, ap->a_cred, td);
1802		if (error != 0)
1803			goto ret;
1804		if (vap->va_atime.tv_sec != VNOVAL) {
1805			if (vp->v_type == VCHR)
1806				vp->v_rdev->si_atime = vap->va_atime;
1807			else
1808				de->de_atime = vap->va_atime;
1809		}
1810		if (vap->va_mtime.tv_sec != VNOVAL) {
1811			if (vp->v_type == VCHR)
1812				vp->v_rdev->si_mtime = vap->va_mtime;
1813			else
1814				de->de_mtime = vap->va_mtime;
1815		}
1816		c = 1;
1817	}
1818
1819	if (c) {
1820		if (vp->v_type == VCHR)
1821			vfs_timestamp(&vp->v_rdev->si_ctime);
1822		else
1823			vfs_timestamp(&de->de_mtime);
1824	}
1825
1826ret:
1827	sx_xunlock(&VFSTODEVFS(vp->v_mount)->dm_lock);
1828	return (error);
1829}
1830
1831#ifdef MAC
1832static int
1833devfs_setlabel(struct vop_setlabel_args *ap)
1834{
1835	struct vnode *vp;
1836	struct devfs_dirent *de;
1837
1838	vp = ap->a_vp;
1839	de = vp->v_data;
1840
1841	mac_vnode_relabel(ap->a_cred, vp, ap->a_label);
1842	mac_devfs_update(vp->v_mount, de, vp);
1843
1844	return (0);
1845}
1846#endif
1847
1848static int
1849devfs_stat_f(struct file *fp, struct stat *sb, struct ucred *cred)
1850{
1851
1852	return (vnops.fo_stat(fp, sb, cred));
1853}
1854
1855static int
1856devfs_symlink(struct vop_symlink_args *ap)
1857{
1858	int i, error;
1859	struct devfs_dirent *dd;
1860	struct devfs_dirent *de, *de_covered, *de_dotdot;
1861	struct devfs_mount *dmp;
1862
1863	error = priv_check(curthread, PRIV_DEVFS_SYMLINK);
1864	if (error)
1865		return(error);
1866	dmp = VFSTODEVFS(ap->a_dvp->v_mount);
1867	if (devfs_populate_vp(ap->a_dvp) != 0)
1868		return (ENOENT);
1869
1870	dd = ap->a_dvp->v_data;
1871	de = devfs_newdirent(ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen);
1872	de->de_flags = DE_USER;
1873	de->de_uid = 0;
1874	de->de_gid = 0;
1875	de->de_mode = 0755;
1876	de->de_inode = alloc_unr(devfs_inos);
1877	de->de_dir = dd;
1878	de->de_dirent->d_type = DT_LNK;
1879	i = strlen(ap->a_target) + 1;
1880	de->de_symlink = malloc(i, M_DEVFS, M_WAITOK);
1881	bcopy(ap->a_target, de->de_symlink, i);
1882#ifdef MAC
1883	mac_devfs_create_symlink(ap->a_cnp->cn_cred, dmp->dm_mount, dd, de);
1884#endif
1885	de_covered = devfs_find(dd, de->de_dirent->d_name,
1886	    de->de_dirent->d_namlen, 0);
1887	if (de_covered != NULL) {
1888		if ((de_covered->de_flags & DE_USER) != 0) {
1889			devfs_delete(dmp, de, DEVFS_DEL_NORECURSE);
1890			sx_xunlock(&dmp->dm_lock);
1891			return (EEXIST);
1892		}
1893		KASSERT((de_covered->de_flags & DE_COVERED) == 0,
1894		    ("devfs_symlink: entry %p already covered", de_covered));
1895		de_covered->de_flags |= DE_COVERED;
1896	}
1897
1898	de_dotdot = TAILQ_FIRST(&dd->de_dlist);		/* "." */
1899	de_dotdot = TAILQ_NEXT(de_dotdot, de_list);	/* ".." */
1900	TAILQ_INSERT_AFTER(&dd->de_dlist, de_dotdot, de, de_list);
1901	devfs_dir_ref_de(dmp, dd);
1902	devfs_rules_apply(dmp, de);
1903
1904	return (devfs_allocv(de, ap->a_dvp->v_mount, LK_EXCLUSIVE, ap->a_vpp));
1905}
1906
1907static int
1908devfs_truncate_f(struct file *fp, off_t length, struct ucred *cred, struct thread *td)
1909{
1910
1911	return (vnops.fo_truncate(fp, length, cred, td));
1912}
1913
1914static int
1915devfs_write_f(struct file *fp, struct uio *uio, struct ucred *cred,
1916    int flags, struct thread *td)
1917{
1918	struct cdev *dev;
1919	int error, ioflag, ref;
1920	ssize_t resid;
1921	struct cdevsw *dsw;
1922	struct file *fpop;
1923
1924	if (uio->uio_resid > DEVFS_IOSIZE_MAX)
1925		return (EINVAL);
1926	fpop = td->td_fpop;
1927	error = devfs_fp_check(fp, &dev, &dsw, &ref);
1928	if (error != 0) {
1929		error = vnops.fo_write(fp, uio, cred, flags, td);
1930		return (error);
1931	}
1932	KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td));
1933	ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC);
1934	if (ioflag & O_DIRECT)
1935		ioflag |= IO_DIRECT;
1936	foffset_lock_uio(fp, uio, flags | FOF_NOLOCK);
1937
1938	resid = uio->uio_resid;
1939
1940	error = dsw->d_write(dev, uio, ioflag);
1941	if (uio->uio_resid != resid || (error == 0 && resid != 0)) {
1942		devfs_timestamp(&dev->si_ctime);
1943		dev->si_mtime = dev->si_ctime;
1944	}
1945	td->td_fpop = fpop;
1946	dev_relthread(dev, ref);
1947
1948	foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF_W);
1949	return (error);
1950}
1951
1952static int
1953devfs_mmap_f(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
1954    vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
1955    struct thread *td)
1956{
1957	struct cdev *dev;
1958	struct cdevsw *dsw;
1959	struct mount *mp;
1960	struct vnode *vp;
1961	struct file *fpop;
1962	vm_object_t object;
1963	vm_prot_t maxprot;
1964	int error, ref;
1965
1966	vp = fp->f_vnode;
1967
1968	/*
1969	 * Ensure that file and memory protections are
1970	 * compatible.
1971	 */
1972	mp = vp->v_mount;
1973	if (mp != NULL && (mp->mnt_flag & MNT_NOEXEC) != 0) {
1974		maxprot = VM_PROT_NONE;
1975		if ((prot & VM_PROT_EXECUTE) != 0)
1976			return (EACCES);
1977	} else
1978		maxprot = VM_PROT_EXECUTE;
1979	if ((fp->f_flag & FREAD) != 0)
1980		maxprot |= VM_PROT_READ;
1981	else if ((prot & VM_PROT_READ) != 0)
1982		return (EACCES);
1983
1984	/*
1985	 * If we are sharing potential changes via MAP_SHARED and we
1986	 * are trying to get write permission although we opened it
1987	 * without asking for it, bail out.
1988	 *
1989	 * Note that most character devices always share mappings.
1990	 * The one exception is that D_MMAP_ANON devices
1991	 * (i.e. /dev/zero) permit private writable mappings.
1992	 *
1993	 * Rely on vm_mmap_cdev() to fail invalid MAP_PRIVATE requests
1994	 * as well as updating maxprot to permit writing for
1995	 * D_MMAP_ANON devices rather than doing that here.
1996	 */
1997	if ((flags & MAP_SHARED) != 0) {
1998		if ((fp->f_flag & FWRITE) != 0)
1999			maxprot |= VM_PROT_WRITE;
2000		else if ((prot & VM_PROT_WRITE) != 0)
2001			return (EACCES);
2002	}
2003	maxprot &= cap_maxprot;
2004
2005	fpop = td->td_fpop;
2006	error = devfs_fp_check(fp, &dev, &dsw, &ref);
2007	if (error != 0)
2008		return (error);
2009
2010	error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, dev, dsw, &foff,
2011	    &object);
2012	td->td_fpop = fpop;
2013	dev_relthread(dev, ref);
2014	if (error != 0)
2015		return (error);
2016
2017	error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object,
2018	    foff, FALSE, td);
2019	if (error != 0)
2020		vm_object_deallocate(object);
2021	return (error);
2022}
2023
2024dev_t
2025dev2udev(struct cdev *x)
2026{
2027	if (x == NULL)
2028		return (NODEV);
2029	return (cdev2priv(x)->cdp_inode);
2030}
2031
2032static int
2033devfs_cmp_f(struct file *fp1, struct file *fp2, struct thread *td)
2034{
2035	if (fp2->f_type != DTYPE_VNODE || fp2->f_ops != &devfs_ops_f)
2036		return (3);
2037	return (kcmp_cmp((uintptr_t)fp1->f_data, (uintptr_t)fp2->f_data));
2038}
2039
2040static struct fileops devfs_ops_f = {
2041	.fo_read =	devfs_read_f,
2042	.fo_write =	devfs_write_f,
2043	.fo_truncate =	devfs_truncate_f,
2044	.fo_ioctl =	devfs_ioctl_f,
2045	.fo_poll =	devfs_poll_f,
2046	.fo_kqfilter =	devfs_kqfilter_f,
2047	.fo_stat =	devfs_stat_f,
2048	.fo_close =	devfs_close_f,
2049	.fo_chmod =	vn_chmod,
2050	.fo_chown =	vn_chown,
2051	.fo_sendfile =	vn_sendfile,
2052	.fo_seek =	vn_seek,
2053	.fo_fill_kinfo = vn_fill_kinfo,
2054	.fo_mmap =	devfs_mmap_f,
2055	.fo_cmp =	devfs_cmp_f,
2056	.fo_flags =	DFLAG_PASSABLE | DFLAG_SEEKABLE
2057};
2058
2059/* Vops for non-CHR vnodes in /dev. */
2060static struct vop_vector devfs_vnodeops = {
2061	.vop_default =		&default_vnodeops,
2062
2063	.vop_access =		devfs_access,
2064	.vop_getattr =		devfs_getattr,
2065	.vop_ioctl =		devfs_rioctl,
2066	.vop_lookup =		devfs_lookup,
2067	.vop_mknod =		devfs_mknod,
2068	.vop_pathconf =		devfs_pathconf,
2069	.vop_read =		devfs_rread,
2070	.vop_readdir =		devfs_readdir,
2071	.vop_readlink =		devfs_readlink,
2072	.vop_reclaim =		devfs_reclaim,
2073	.vop_remove =		devfs_remove,
2074	.vop_revoke =		devfs_revoke,
2075	.vop_setattr =		devfs_setattr,
2076#ifdef MAC
2077	.vop_setlabel =		devfs_setlabel,
2078#endif
2079	.vop_symlink =		devfs_symlink,
2080	.vop_vptocnp =		devfs_vptocnp,
2081	.vop_lock1 =		vop_lock,
2082	.vop_unlock =		vop_unlock,
2083	.vop_islocked =		vop_islocked,
2084	.vop_add_writecount =	vop_stdadd_writecount_nomsync,
2085};
2086VFS_VOP_VECTOR_REGISTER(devfs_vnodeops);
2087
2088/* Vops for VCHR vnodes in /dev. */
2089static struct vop_vector devfs_specops = {
2090	.vop_default =		&default_vnodeops,
2091
2092	.vop_access =		devfs_access,
2093	.vop_bmap =		VOP_PANIC,
2094	.vop_close =		devfs_close,
2095	.vop_create =		VOP_PANIC,
2096	.vop_fsync =		vop_stdfsync,
2097	.vop_getattr =		devfs_getattr,
2098	.vop_ioctl =		devfs_ioctl,
2099	.vop_link =		VOP_PANIC,
2100	.vop_mkdir =		VOP_PANIC,
2101	.vop_mknod =		VOP_PANIC,
2102	.vop_open =		devfs_open,
2103	.vop_pathconf =		devfs_pathconf,
2104	.vop_poll =		dead_poll,
2105	.vop_print =		devfs_print,
2106	.vop_read =		dead_read,
2107	.vop_readdir =		VOP_PANIC,
2108	.vop_readlink =		VOP_PANIC,
2109	.vop_reallocblks =	VOP_PANIC,
2110	.vop_reclaim =		devfs_reclaim_vchr,
2111	.vop_remove =		devfs_remove,
2112	.vop_rename =		VOP_PANIC,
2113	.vop_revoke =		devfs_revoke,
2114	.vop_rmdir =		VOP_PANIC,
2115	.vop_setattr =		devfs_setattr,
2116#ifdef MAC
2117	.vop_setlabel =		devfs_setlabel,
2118#endif
2119	.vop_strategy =		VOP_PANIC,
2120	.vop_symlink =		VOP_PANIC,
2121	.vop_vptocnp =		devfs_vptocnp,
2122	.vop_write =		dead_write,
2123	.vop_lock1 =		vop_lock,
2124	.vop_unlock =		vop_unlock,
2125	.vop_islocked =		vop_islocked,
2126	.vop_add_writecount =	vop_stdadd_writecount_nomsync,
2127};
2128VFS_VOP_VECTOR_REGISTER(devfs_specops);
2129
2130/*
2131 * Our calling convention to the device drivers used to be that we passed
2132 * vnode.h IO_* flags to read()/write(), but we're moving to fcntl.h O_
2133 * flags instead since that's what open(), close() and ioctl() takes and
2134 * we don't really want vnode.h in device drivers.
2135 * We solved the source compatibility by redefining some vnode flags to
2136 * be the same as the fcntl ones and by sending down the bitwise OR of
2137 * the respective fcntl/vnode flags.  These CTASSERTS make sure nobody
2138 * pulls the rug out under this.
2139 */
2140CTASSERT(O_NONBLOCK == IO_NDELAY);
2141CTASSERT(O_FSYNC == IO_SYNC);
2142