xref: /netbsd-src/sys/miscfs/kernfs/kernfs_vnops.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*	$NetBSD: kernfs_vnops.c,v 1.32 1994/12/14 18:47:42 mycroft Exp $	*/
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software donated to Berkeley by
8  * Jan-Simon Pendry.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)kernfs_vnops.c	8.9 (Berkeley) 6/15/94
39  */
40 
41 /*
42  * Kernel parameter filesystem (/kern)
43  */
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/kernel.h>
48 #include <sys/vmmeter.h>
49 #include <sys/types.h>
50 #include <sys/time.h>
51 #include <sys/proc.h>
52 #include <sys/vnode.h>
53 #include <sys/malloc.h>
54 #include <sys/file.h>
55 #include <sys/stat.h>
56 #include <sys/mount.h>
57 #include <sys/namei.h>
58 #include <sys/buf.h>
59 #include <sys/dirent.h>
60 #include <sys/msgbuf.h>
61 #include <miscfs/kernfs/kernfs.h>
62 
63 #define KSTRING	256		/* Largest I/O available via this filesystem */
64 #define	UIO_MX 32
65 
66 #define	READ_MODE	(S_IRUSR|S_IRGRP|S_IROTH)
67 #define	WRITE_MODE	(S_IWUSR|S_IRUSR|S_IRGRP|S_IROTH)
68 #define DIR_MODE	(S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH)
69 
70 struct kern_target {
71 	u_char kt_type;
72 	u_char kt_namlen;
73 	char *kt_name;
74 	void *kt_data;
75 #define	KTT_NULL	 1
76 #define	KTT_TIME	 5
77 #define KTT_INT		17
78 #define	KTT_STRING	31
79 #define KTT_HOSTNAME	47
80 #define KTT_AVENRUN	53
81 #define KTT_DEVICE	71
82 #define	KTT_MSGBUF	89
83 	u_char kt_tag;
84 	u_char kt_vtype;
85 	mode_t kt_mode;
86 } kern_targets[] = {
87 /* NOTE: The name must be less than UIO_MX-16 chars in length */
88 #define N(s) sizeof(s)-1, s
89      /*        name            data          tag           type  ro/rw */
90      { DT_DIR, N("."),         0,            KTT_NULL,     VDIR, DIR_MODE   },
91      { DT_DIR, N(".."),        0,            KTT_NULL,     VDIR, DIR_MODE   },
92      { DT_REG, N("boottime"),  &boottime.tv_sec, KTT_INT,  VREG, READ_MODE  },
93      { DT_REG, N("copyright"), copyright,    KTT_STRING,   VREG, READ_MODE  },
94      { DT_REG, N("hostname"),  0,            KTT_HOSTNAME, VREG, WRITE_MODE },
95      { DT_REG, N("hz"),        &hz,          KTT_INT,      VREG, READ_MODE  },
96      { DT_REG, N("loadavg"),   0,            KTT_AVENRUN,  VREG, READ_MODE  },
97      { DT_REG, N("msgbuf"),    0,	     KTT_MSGBUF,   VREG, READ_MODE  },
98      { DT_REG, N("pagesize"),  &cnt.v_page_size, KTT_INT,  VREG, READ_MODE  },
99      { DT_REG, N("physmem"),   &physmem,     KTT_INT,      VREG, READ_MODE  },
100 #if 0
101      { DT_DIR, N("root"),      0,            KTT_NULL,     VDIR, DIR_MODE   },
102 #endif
103      { DT_BLK, N("rootdev"),   &rootdev,     KTT_DEVICE,   VBLK, READ_MODE  },
104      { DT_CHR, N("rrootdev"),  &rrootdev,    KTT_DEVICE,   VCHR, READ_MODE  },
105      { DT_REG, N("time"),      0,            KTT_TIME,     VREG, READ_MODE  },
106      { DT_REG, N("version"),   version,      KTT_STRING,   VREG, READ_MODE  },
107 #undef N
108 };
109 static int nkern_targets = sizeof(kern_targets) / sizeof(kern_targets[0]);
110 
111 int
112 kernfs_xread(kt, off, bufp, len)
113 	struct kern_target *kt;
114 	int off;
115 	char **bufp;
116 	int len;
117 {
118 
119 	switch (kt->kt_tag) {
120 	case KTT_TIME: {
121 		struct timeval tv;
122 
123 		microtime(&tv);
124 		sprintf(*bufp, "%d %d\n", tv.tv_sec, tv.tv_usec);
125 		break;
126 	}
127 
128 	case KTT_INT: {
129 		int *ip = kt->kt_data;
130 
131 		sprintf(*bufp, "%d\n", *ip);
132 		break;
133 	}
134 
135 	case KTT_STRING: {
136 		char *cp = kt->kt_data;
137 
138 		*bufp = cp;
139 		break;
140 	}
141 
142 	case KTT_MSGBUF: {
143 		extern struct msgbuf *msgbufp;
144 		long n;
145 
146 		if (off >= MSG_BSIZE)
147 			return (0);
148 		n = msgbufp->msg_bufx + off;
149 		if (n >= MSG_BSIZE)
150 			n -= MSG_BSIZE;
151 		len = min(MSG_BSIZE - n, MSG_BSIZE - off);
152 		*bufp = msgbufp->msg_bufc + n;
153 		return (len);
154 	}
155 
156 	case KTT_HOSTNAME: {
157 		char *cp = hostname;
158 		int xlen = hostnamelen;
159 
160 		if (xlen >= (len-2))
161 			return (EINVAL);
162 
163 		bcopy(cp, *bufp, xlen);
164 		(*bufp)[xlen] = '\n';
165 		(*bufp)[xlen+1] = '\0';
166 		break;
167 	}
168 
169 	case KTT_AVENRUN:
170 		averunnable.fscale = FSCALE;
171 		sprintf(*bufp, "%ld %ld %ld %ld\n",
172 		    averunnable.ldavg[0], averunnable.ldavg[1],
173 		    averunnable.ldavg[2], averunnable.fscale);
174 		break;
175 
176 	default:
177 		return (0);
178 	}
179 
180 	len = strlen(*bufp);
181 	if (len <= off)
182 		return (0);
183 	*bufp += off;
184 	return (len - off);
185 }
186 
187 int
188 kernfs_xwrite(kt, buf, len)
189 	struct kern_target *kt;
190 	char *buf;
191 	int len;
192 {
193 
194 	switch (kt->kt_tag) {
195 	case KTT_HOSTNAME:
196 		if (buf[len-1] == '\n')
197 			--len;
198 		bcopy(buf, hostname, len);
199 		hostname[len] = '\0';
200 		hostnamelen = len;
201 		return (0);
202 
203 	default:
204 		return (EIO);
205 	}
206 }
207 
208 
209 /*
210  * vp is the current namei directory
211  * ndp is the name to locate in that directory...
212  */
213 kernfs_lookup(ap)
214 	struct vop_lookup_args /* {
215 		struct vnode * a_dvp;
216 		struct vnode ** a_vpp;
217 		struct componentname * a_cnp;
218 	} */ *ap;
219 {
220 	struct componentname *cnp = ap->a_cnp;
221 	struct vnode **vpp = ap->a_vpp;
222 	struct vnode *dvp = ap->a_dvp;
223 	char *pname = cnp->cn_nameptr;
224 	struct kern_target *kt;
225 	struct vnode *fvp;
226 	int error, i;
227 
228 #ifdef KERNFS_DIAGNOSTIC
229 	printf("kernfs_lookup(%x)\n", ap);
230 	printf("kernfs_lookup(dp = %x, vpp = %x, cnp = %x)\n", dvp, vpp, ap->a_cnp);
231 	printf("kernfs_lookup(%s)\n", pname);
232 #endif
233 
234 	if (cnp->cn_namelen == 1 && *pname == '.') {
235 		*vpp = dvp;
236 		VREF(dvp);
237 		/*VOP_LOCK(dvp);*/
238 		return (0);
239 	}
240 
241 #if 0
242 	if (cnp->cn_namelen == 4 && bcmp(pname, "root", 4) == 0) {
243 		*vpp = rootdir;
244 		VREF(rootdir);
245 		VOP_LOCK(rootdir);
246 		return (0);
247 	}
248 #endif
249 
250 	*vpp = NULLVP;
251 
252 	for (error = ENOENT, kt = kern_targets, i = 0; i < nkern_targets;
253 	     kt++, i++) {
254 		if (cnp->cn_namelen == kt->kt_namlen &&
255 		    bcmp(kt->kt_name, pname, cnp->cn_namelen) == 0) {
256 			error = 0;
257 			break;
258 		}
259 	}
260 
261 #ifdef KERNFS_DIAGNOSTIC
262 	printf("kernfs_lookup: i = %d, error = %d\n", i, error);
263 #endif
264 
265 	if (error)
266 		return (error);
267 
268 	if (kt->kt_tag == KTT_DEVICE) {
269 		dev_t *dp = kt->kt_data;
270 	loop:
271 		if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp))
272 			return (ENOENT);
273 		*vpp = fvp;
274 		if (vget(fvp, 1))
275 			goto loop;
276 		return (0);
277 	}
278 
279 #ifdef KERNFS_DIAGNOSTIC
280 	printf("kernfs_lookup: allocate new vnode\n");
281 #endif
282 	if (error = getnewvnode(VT_KERNFS, dvp->v_mount, kernfs_vnodeop_p,
283 	    &fvp))
284 		return (error);
285 
286 	MALLOC(fvp->v_data, void *, sizeof(struct kernfs_node), M_TEMP,
287 	    M_WAITOK);
288 	VTOKERN(fvp)->kf_kt = kt;
289 	fvp->v_type = kt->kt_vtype;
290 	*vpp = fvp;
291 
292 #ifdef KERNFS_DIAGNOSTIC
293 	printf("kernfs_lookup: newvp = %x\n", fvp);
294 #endif
295 	return (0);
296 }
297 
298 kernfs_open(ap)
299 	struct vop_open_args /* {
300 		struct vnode *a_vp;
301 		int  a_mode;
302 		struct ucred *a_cred;
303 		struct proc *a_p;
304 	} */ *ap;
305 {
306 
307 	/* Only need to check access permissions. */
308 	return (0);
309 }
310 
311 int
312 kernfs_access(ap)
313 	struct vop_access_args /* {
314 		struct vnode *a_vp;
315 		int  a_mode;
316 		struct ucred *a_cred;
317 		struct proc *a_p;
318 	} */ *ap;
319 {
320 	struct vnode *vp = ap->a_vp;
321 	struct ucred *cred = ap->a_cred;
322 	mode_t amode = ap->a_mode;
323 	mode_t fmode =
324 	    (vp->v_flag & VROOT) ? DIR_MODE : VTOKERN(vp)->kf_kt->kt_mode;
325 	mode_t mask = 0;
326 	gid_t *gp;
327 	int i;
328 
329 	/* Some files are simply not modifiable. */
330 	if ((amode & VWRITE) && (fmode & (S_IWUSR|S_IWGRP|S_IWOTH)) == 0)
331 		return (EPERM);
332 
333 	/* Root can do anything else. */
334 	if (cred->cr_uid == 0)
335 		return (0);
336 
337 	/* Check for group 0 (wheel) permissions. */
338 	for (i = 0, gp = cred->cr_groups; i < cred->cr_ngroups; i++, gp++)
339 		if (*gp == 0) {
340 			if (amode & VEXEC)
341 				mask |= S_IXGRP;
342 			if (amode & VREAD)
343 				mask |= S_IRGRP;
344 			if (amode & VWRITE)
345 				mask |= S_IWGRP;
346 			return ((fmode & mask) == mask ?  0 : EACCES);
347 		}
348 
349         /* Otherwise, check everyone else. */
350 	if (amode & VEXEC)
351 		mask |= S_IXOTH;
352 	if (amode & VREAD)
353 		mask |= S_IROTH;
354 	if (amode & VWRITE)
355 		mask |= S_IWOTH;
356 	return ((fmode & mask) == mask ? 0 : EACCES);
357 }
358 
359 kernfs_getattr(ap)
360 	struct vop_getattr_args /* {
361 		struct vnode *a_vp;
362 		struct vattr *a_vap;
363 		struct ucred *a_cred;
364 		struct proc *a_p;
365 	} */ *ap;
366 {
367 	struct vnode *vp = ap->a_vp;
368 	struct vattr *vap = ap->a_vap;
369 	int error = 0;
370 	char strbuf[KSTRING], *buf;
371 
372 	bzero((caddr_t) vap, sizeof(*vap));
373 	vattr_null(vap);
374 	vap->va_uid = 0;
375 	vap->va_gid = 0;
376 	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
377 	vap->va_size = 0;
378 	vap->va_blocksize = DEV_BSIZE;
379 	microtime(&vap->va_atime);
380 	vap->va_mtime = vap->va_atime;
381 	vap->va_ctime = vap->va_ctime;
382 	vap->va_gen = 0;
383 	vap->va_flags = 0;
384 	vap->va_rdev = 0;
385 	vap->va_bytes = 0;
386 
387 	if (vp->v_flag & VROOT) {
388 #ifdef KERNFS_DIAGNOSTIC
389 		printf("kernfs_getattr: stat rootdir\n");
390 #endif
391 		vap->va_type = VDIR;
392 		vap->va_mode = DIR_MODE;
393 		vap->va_nlink = 2;
394 		vap->va_fileid = 2;
395 		vap->va_size = DEV_BSIZE;
396 	} else {
397 		struct kern_target *kt = VTOKERN(vp)->kf_kt;
398 		int nbytes, total;
399 #ifdef KERNFS_DIAGNOSTIC
400 		printf("kernfs_getattr: stat target %s\n", kt->kt_name);
401 #endif
402 		vap->va_type = kt->kt_vtype;
403 		vap->va_mode = kt->kt_mode;
404 		vap->va_nlink = 1;
405 		vap->va_fileid = 1 + (kt - kern_targets) / sizeof(*kt);
406 		total = 0;
407 		while (buf = strbuf,
408 		       nbytes = kernfs_xread(kt, total, &buf, sizeof(strbuf)))
409 			total += nbytes;
410 		vap->va_size = total;
411 	}
412 
413 #ifdef KERNFS_DIAGNOSTIC
414 	printf("kernfs_getattr: return error %d\n", error);
415 #endif
416 	return (error);
417 }
418 
419 kernfs_setattr(ap)
420 	struct vop_setattr_args /* {
421 		struct vnode *a_vp;
422 		struct vattr *a_vap;
423 		struct ucred *a_cred;
424 		struct proc *a_p;
425 	} */ *ap;
426 {
427 
428 	/*
429 	 * Silently ignore attribute changes.
430 	 * This allows for open with truncate to have no
431 	 * effect until some data is written.  I want to
432 	 * do it this way because all writes are atomic.
433 	 */
434 	return (0);
435 }
436 
437 int
438 kernfs_read(ap)
439 	struct vop_read_args /* {
440 		struct vnode *a_vp;
441 		struct uio *a_uio;
442 		int  a_ioflag;
443 		struct ucred *a_cred;
444 	} */ *ap;
445 {
446 	struct vnode *vp = ap->a_vp;
447 	struct uio *uio = ap->a_uio;
448 	struct kern_target *kt;
449 	char strbuf[KSTRING], *buf;
450 	int off, len;
451 	int error;
452 
453 	if (vp->v_type == VDIR)
454 		return (EOPNOTSUPP);
455 
456 	kt = VTOKERN(vp)->kf_kt;
457 
458 #ifdef KERNFS_DIAGNOSTIC
459 	printf("kern_read %s\n", kt->kt_name);
460 #endif
461 
462 	off = uio->uio_offset;
463 #if 0
464 	while (buf = strbuf,
465 #else
466 	if (buf = strbuf,
467 #endif
468 	    len = kernfs_xread(kt, off, &buf, sizeof(strbuf))) {
469 		if (error = uiomove(buf, len, uio))
470 			return (error);
471 		off += len;
472 	}
473 	return (0);
474 }
475 
476 int
477 kernfs_write(ap)
478 	struct vop_write_args /* {
479 		struct vnode *a_vp;
480 		struct uio *a_uio;
481 		int  a_ioflag;
482 		struct ucred *a_cred;
483 	} */ *ap;
484 {
485 	struct vnode *vp = ap->a_vp;
486 	struct uio *uio = ap->a_uio;
487 	struct kern_target *kt;
488 	int error, xlen;
489 	char strbuf[KSTRING];
490 
491 	if (vp->v_type == VDIR)
492 		return (EOPNOTSUPP);
493 
494 	kt = VTOKERN(vp)->kf_kt;
495 
496 	if (uio->uio_offset != 0)
497 		return (EINVAL);
498 
499 	xlen = min(uio->uio_resid, KSTRING-1);
500 	if (error = uiomove(strbuf, xlen, uio))
501 		return (error);
502 
503 	if (uio->uio_resid != 0)
504 		return (EIO);
505 
506 	strbuf[xlen] = '\0';
507 	xlen = strlen(strbuf);
508 	return (kernfs_xwrite(kt, strbuf, xlen));
509 }
510 
511 kernfs_readdir(ap)
512 	struct vop_readdir_args /* {
513 		struct vnode *a_vp;
514 		struct uio *a_uio;
515 		struct ucred *a_cred;
516 		int *a_eofflag;
517 		u_long *a_cookies;
518 		int a_ncookies;
519 	} */ *ap;
520 {
521 	struct uio *uio = ap->a_uio;
522 	struct kern_target *kt;
523 	struct dirent d;
524 	int i;
525 	int error;
526 
527 	if (ap->a_vp->v_type != VDIR)
528 		return (ENOTDIR);
529 
530 	/*
531 	 * We don't allow exporting kernfs mounts, and currently local
532 	 * requests do not need cookies.
533 	 */
534 	if (ap->a_ncookies != NULL)
535 		panic("kernfs_readdir: not hungry");
536 
537 	i = uio->uio_offset / UIO_MX;
538 	error = 0;
539 	for (kt = &kern_targets[i];
540 	     uio->uio_resid >= UIO_MX && i < nkern_targets; kt++, i++) {
541 		struct dirent *dp = &d;
542 #ifdef KERNFS_DIAGNOSTIC
543 		printf("kernfs_readdir: i = %d\n", i);
544 #endif
545 
546 		if (kt->kt_tag == KTT_DEVICE) {
547 			dev_t *dp = kt->kt_data;
548 			struct vnode *fvp;
549 
550 			if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp))
551 				continue;
552 		}
553 
554 		bzero((caddr_t)dp, UIO_MX);
555 		dp->d_namlen = kt->kt_namlen;
556 		bcopy(kt->kt_name, dp->d_name, kt->kt_namlen+1);
557 
558 #ifdef KERNFS_DIAGNOSTIC
559 		printf("kernfs_readdir: name = %s, len = %d\n",
560 				dp->d_name, dp->d_namlen);
561 #endif
562 		/*
563 		 * Fill in the remaining fields
564 		 */
565 		dp->d_reclen = UIO_MX;
566 		dp->d_fileno = i + 3;
567 		dp->d_type = kt->kt_type;
568 		/*
569 		 * And ship to userland
570 		 */
571 		if (error = uiomove((caddr_t)dp, UIO_MX, uio))
572 			break;
573 	}
574 
575 	uio->uio_offset = i * UIO_MX;
576 
577 	return (error);
578 }
579 
580 kernfs_inactive(ap)
581 	struct vop_inactive_args /* {
582 		struct vnode *a_vp;
583 	} */ *ap;
584 {
585 	struct vnode *vp = ap->a_vp;
586 
587 #ifdef KERNFS_DIAGNOSTIC
588 	printf("kernfs_inactive(%x)\n", vp);
589 #endif
590 	/*
591 	 * Clear out the v_type field to avoid
592 	 * nasty things happening in vgone().
593 	 */
594 	vp->v_type = VNON;
595 	return (0);
596 }
597 
598 kernfs_reclaim(ap)
599 	struct vop_reclaim_args /* {
600 		struct vnode *a_vp;
601 	} */ *ap;
602 {
603 	struct vnode *vp = ap->a_vp;
604 
605 #ifdef KERNFS_DIAGNOSTIC
606 	printf("kernfs_reclaim(%x)\n", vp);
607 #endif
608 	if (vp->v_data) {
609 		FREE(vp->v_data, M_TEMP);
610 		vp->v_data = 0;
611 	}
612 	return (0);
613 }
614 
615 /*
616  * Return POSIX pathconf information applicable to special devices.
617  */
618 kernfs_pathconf(ap)
619 	struct vop_pathconf_args /* {
620 		struct vnode *a_vp;
621 		int a_name;
622 		register_t *a_retval;
623 	} */ *ap;
624 {
625 
626 	switch (ap->a_name) {
627 	case _PC_LINK_MAX:
628 		*ap->a_retval = LINK_MAX;
629 		return (0);
630 	case _PC_MAX_CANON:
631 		*ap->a_retval = MAX_CANON;
632 		return (0);
633 	case _PC_MAX_INPUT:
634 		*ap->a_retval = MAX_INPUT;
635 		return (0);
636 	case _PC_PIPE_BUF:
637 		*ap->a_retval = PIPE_BUF;
638 		return (0);
639 	case _PC_CHOWN_RESTRICTED:
640 		*ap->a_retval = 1;
641 		return (0);
642 	case _PC_VDISABLE:
643 		*ap->a_retval = _POSIX_VDISABLE;
644 		return (0);
645 	default:
646 		return (EINVAL);
647 	}
648 	/* NOTREACHED */
649 }
650 
651 /*
652  * Print out the contents of a /dev/fd vnode.
653  */
654 /* ARGSUSED */
655 kernfs_print(ap)
656 	struct vop_print_args /* {
657 		struct vnode *a_vp;
658 	} */ *ap;
659 {
660 
661 	printf("tag VT_KERNFS, kernfs vnode\n");
662 	return (0);
663 }
664 
665 /*void*/
666 kernfs_vfree(ap)
667 	struct vop_vfree_args /* {
668 		struct vnode *a_pvp;
669 		ino_t a_ino;
670 		int a_mode;
671 	} */ *ap;
672 {
673 
674 	return (0);
675 }
676 
677 /*
678  * /dev/fd vnode unsupported operation
679  */
680 kernfs_enotsupp()
681 {
682 
683 	return (EOPNOTSUPP);
684 }
685 
686 /*
687  * /dev/fd "should never get here" operation
688  */
689 kernfs_badop()
690 {
691 
692 	panic("kernfs: bad op");
693 	/* NOTREACHED */
694 }
695 
696 /*
697  * kernfs vnode null operation
698  */
699 kernfs_nullop()
700 {
701 
702 	return (0);
703 }
704 
705 #define kernfs_create ((int (*) __P((struct  vop_create_args *)))kernfs_enotsupp)
706 #define kernfs_mknod ((int (*) __P((struct  vop_mknod_args *)))kernfs_enotsupp)
707 #define kernfs_close ((int (*) __P((struct  vop_close_args *)))nullop)
708 #define kernfs_ioctl ((int (*) __P((struct  vop_ioctl_args *)))kernfs_enotsupp)
709 #define kernfs_select ((int (*) __P((struct  vop_select_args *)))kernfs_enotsupp)
710 #define kernfs_mmap ((int (*) __P((struct  vop_mmap_args *)))kernfs_enotsupp)
711 #define kernfs_fsync ((int (*) __P((struct  vop_fsync_args *)))nullop)
712 #define kernfs_seek ((int (*) __P((struct  vop_seek_args *)))nullop)
713 #define kernfs_remove ((int (*) __P((struct  vop_remove_args *)))kernfs_enotsupp)
714 #define kernfs_link ((int (*) __P((struct  vop_link_args *)))kernfs_enotsupp)
715 #define kernfs_rename ((int (*) __P((struct  vop_rename_args *)))kernfs_enotsupp)
716 #define kernfs_mkdir ((int (*) __P((struct  vop_mkdir_args *)))kernfs_enotsupp)
717 #define kernfs_rmdir ((int (*) __P((struct  vop_rmdir_args *)))kernfs_enotsupp)
718 #define kernfs_symlink ((int (*) __P((struct vop_symlink_args *)))kernfs_enotsupp)
719 #define kernfs_readlink \
720 	((int (*) __P((struct  vop_readlink_args *)))kernfs_enotsupp)
721 #define kernfs_abortop ((int (*) __P((struct  vop_abortop_args *)))nullop)
722 #define kernfs_lock ((int (*) __P((struct  vop_lock_args *)))nullop)
723 #define kernfs_unlock ((int (*) __P((struct  vop_unlock_args *)))nullop)
724 #define kernfs_bmap ((int (*) __P((struct  vop_bmap_args *)))kernfs_badop)
725 #define kernfs_strategy ((int (*) __P((struct  vop_strategy_args *)))kernfs_badop)
726 #define kernfs_islocked ((int (*) __P((struct  vop_islocked_args *)))nullop)
727 #define kernfs_advlock ((int (*) __P((struct vop_advlock_args *)))kernfs_enotsupp)
728 #define kernfs_blkatoff \
729 	((int (*) __P((struct  vop_blkatoff_args *)))kernfs_enotsupp)
730 #define kernfs_valloc ((int(*) __P(( \
731 		struct vnode *pvp, \
732 		int mode, \
733 		struct ucred *cred, \
734 		struct vnode **vpp))) kernfs_enotsupp)
735 #define kernfs_truncate \
736 	((int (*) __P((struct  vop_truncate_args *)))kernfs_enotsupp)
737 #define kernfs_update ((int (*) __P((struct  vop_update_args *)))kernfs_enotsupp)
738 #define kernfs_bwrite ((int (*) __P((struct  vop_bwrite_args *)))kernfs_enotsupp)
739 
740 int (**kernfs_vnodeop_p)();
741 struct vnodeopv_entry_desc kernfs_vnodeop_entries[] = {
742 	{ &vop_default_desc, vn_default_error },
743 	{ &vop_lookup_desc, kernfs_lookup },	/* lookup */
744 	{ &vop_create_desc, kernfs_create },	/* create */
745 	{ &vop_mknod_desc, kernfs_mknod },	/* mknod */
746 	{ &vop_open_desc, kernfs_open },	/* open */
747 	{ &vop_close_desc, kernfs_close },	/* close */
748 	{ &vop_access_desc, kernfs_access },	/* access */
749 	{ &vop_getattr_desc, kernfs_getattr },	/* getattr */
750 	{ &vop_setattr_desc, kernfs_setattr },	/* setattr */
751 	{ &vop_read_desc, kernfs_read },	/* read */
752 	{ &vop_write_desc, kernfs_write },	/* write */
753 	{ &vop_ioctl_desc, kernfs_ioctl },	/* ioctl */
754 	{ &vop_select_desc, kernfs_select },	/* select */
755 	{ &vop_mmap_desc, kernfs_mmap },	/* mmap */
756 	{ &vop_fsync_desc, kernfs_fsync },	/* fsync */
757 	{ &vop_seek_desc, kernfs_seek },	/* seek */
758 	{ &vop_remove_desc, kernfs_remove },	/* remove */
759 	{ &vop_link_desc, kernfs_link },	/* link */
760 	{ &vop_rename_desc, kernfs_rename },	/* rename */
761 	{ &vop_mkdir_desc, kernfs_mkdir },	/* mkdir */
762 	{ &vop_rmdir_desc, kernfs_rmdir },	/* rmdir */
763 	{ &vop_symlink_desc, kernfs_symlink },	/* symlink */
764 	{ &vop_readdir_desc, kernfs_readdir },	/* readdir */
765 	{ &vop_readlink_desc, kernfs_readlink },/* readlink */
766 	{ &vop_abortop_desc, kernfs_abortop },	/* abortop */
767 	{ &vop_inactive_desc, kernfs_inactive },/* inactive */
768 	{ &vop_reclaim_desc, kernfs_reclaim },	/* reclaim */
769 	{ &vop_lock_desc, kernfs_lock },	/* lock */
770 	{ &vop_unlock_desc, kernfs_unlock },	/* unlock */
771 	{ &vop_bmap_desc, kernfs_bmap },	/* bmap */
772 	{ &vop_strategy_desc, kernfs_strategy },/* strategy */
773 	{ &vop_print_desc, kernfs_print },	/* print */
774 	{ &vop_islocked_desc, kernfs_islocked },/* islocked */
775 	{ &vop_pathconf_desc, kernfs_pathconf },/* pathconf */
776 	{ &vop_advlock_desc, kernfs_advlock },	/* advlock */
777 	{ &vop_blkatoff_desc, kernfs_blkatoff },/* blkatoff */
778 	{ &vop_valloc_desc, kernfs_valloc },	/* valloc */
779 	{ &vop_vfree_desc, kernfs_vfree },	/* vfree */
780 	{ &vop_truncate_desc, kernfs_truncate },/* truncate */
781 	{ &vop_update_desc, kernfs_update },	/* update */
782 	{ &vop_bwrite_desc, kernfs_bwrite },	/* bwrite */
783 	{ (struct vnodeop_desc*)NULL, (int(*)())NULL }
784 };
785 struct vnodeopv_desc kernfs_vnodeop_opv_desc =
786 	{ &kernfs_vnodeop_p, kernfs_vnodeop_entries };
787