xref: /netbsd-src/sys/miscfs/fdesc/fdesc_vnops.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*	$NetBSD: fdesc_vnops.c,v 1.24 1994/12/14 18:45:21 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  *	@(#)fdesc_vnops.c	8.12 (Berkeley) 8/20/94
39  *
40  * #Id: fdesc_vnops.c,v 1.12 1993/04/06 16:17:17 jsp Exp #
41  */
42 
43 /*
44  * /dev/fd Filesystem
45  */
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/types.h>
50 #include <sys/time.h>
51 #include <sys/proc.h>
52 #include <sys/kernel.h>	/* boottime */
53 #include <sys/resourcevar.h>
54 #include <sys/filedesc.h>
55 #include <sys/vnode.h>
56 #include <sys/malloc.h>
57 #include <sys/file.h>
58 #include <sys/stat.h>
59 #include <sys/mount.h>
60 #include <sys/namei.h>
61 #include <sys/buf.h>
62 #include <sys/dirent.h>
63 #include <miscfs/fdesc/fdesc.h>
64 
65 #define cttyvp(p) ((p)->p_flag & P_CONTROLT ? (p)->p_session->s_ttyvp : NULL)
66 
67 #define FDL_WANT	0x01
68 #define FDL_LOCKED	0x02
69 static int fdcache_lock;
70 
71 dev_t devctty;
72 
73 #if (FD_STDIN != FD_STDOUT-1) || (FD_STDOUT != FD_STDERR-1)
74 FD_STDIN, FD_STDOUT, FD_STDERR must be a sequence n, n+1, n+2
75 #endif
76 
77 #define	NFDCACHE 4
78 
79 #define FD_NHASH(ix) \
80 	(&fdhashtbl[(ix) & fdhash])
81 LIST_HEAD(fdhashhead, fdescnode) *fdhashtbl;
82 u_long fdhash;
83 
84 /*
85  * Initialise cache headers
86  */
87 fdesc_init()
88 {
89 
90 	devctty = makedev(nchrdev, 0);
91 	fdhashtbl = hashinit(NFDCACHE, M_CACHE, &fdhash);
92 }
93 
94 int
95 fdesc_allocvp(ftype, ix, mp, vpp)
96 	fdntype ftype;
97 	int ix;
98 	struct mount *mp;
99 	struct vnode **vpp;
100 {
101 	struct fdhashhead *fc;
102 	struct fdescnode *fd;
103 	int error = 0;
104 
105 	fc = FD_NHASH(ix);
106 loop:
107 	for (fd = fc->lh_first; fd != 0; fd = fd->fd_hash.le_next) {
108 		if (fd->fd_ix == ix && fd->fd_vnode->v_mount == mp) {
109 			if (vget(fd->fd_vnode, 0))
110 				goto loop;
111 			*vpp = fd->fd_vnode;
112 			return (error);
113 		}
114 	}
115 
116 	/*
117 	 * otherwise lock the array while we call getnewvnode
118 	 * since that can block.
119 	 */
120 	if (fdcache_lock & FDL_LOCKED) {
121 		fdcache_lock |= FDL_WANT;
122 		sleep((caddr_t) &fdcache_lock, PINOD);
123 		goto loop;
124 	}
125 	fdcache_lock |= FDL_LOCKED;
126 
127 	error = getnewvnode(VT_FDESC, mp, fdesc_vnodeop_p, vpp);
128 	if (error)
129 		goto out;
130 	MALLOC(fd, void *, sizeof(struct fdescnode), M_TEMP, M_WAITOK);
131 	(*vpp)->v_data = fd;
132 	fd->fd_vnode = *vpp;
133 	fd->fd_type = ftype;
134 	fd->fd_fd = -1;
135 	fd->fd_link = 0;
136 	fd->fd_ix = ix;
137 	LIST_INSERT_HEAD(fc, fd, fd_hash);
138 
139 out:;
140 	fdcache_lock &= ~FDL_LOCKED;
141 
142 	if (fdcache_lock & FDL_WANT) {
143 		fdcache_lock &= ~FDL_WANT;
144 		wakeup((caddr_t) &fdcache_lock);
145 	}
146 
147 	return (error);
148 }
149 
150 /*
151  * vp is the current namei directory
152  * ndp is the name to locate in that directory...
153  */
154 int
155 fdesc_lookup(ap)
156 	struct vop_lookup_args /* {
157 		struct vnode * a_dvp;
158 		struct vnode ** a_vpp;
159 		struct componentname * a_cnp;
160 	} */ *ap;
161 {
162 	struct vnode **vpp = ap->a_vpp;
163 	struct vnode *dvp = ap->a_dvp;
164 	char *pname;
165 	struct proc *p;
166 	int nfiles;
167 	unsigned fd;
168 	int error;
169 	struct vnode *fvp;
170 	char *ln;
171 
172 	pname = ap->a_cnp->cn_nameptr;
173 	if (ap->a_cnp->cn_namelen == 1 && *pname == '.') {
174 		*vpp = dvp;
175 		VREF(dvp);
176 		VOP_LOCK(dvp);
177 		return (0);
178 	}
179 
180 	p = ap->a_cnp->cn_proc;
181 	nfiles = p->p_fd->fd_nfiles;
182 
183 	switch (VTOFDESC(dvp)->fd_type) {
184 	default:
185 	case Flink:
186 	case Fdesc:
187 	case Fctty:
188 		error = ENOTDIR;
189 		goto bad;
190 
191 	case Froot:
192 		if (ap->a_cnp->cn_namelen == 2 && bcmp(pname, "fd", 2) == 0) {
193 			error = fdesc_allocvp(Fdevfd, FD_DEVFD, dvp->v_mount, &fvp);
194 			if (error)
195 				goto bad;
196 			*vpp = fvp;
197 			fvp->v_type = VDIR;
198 			VOP_LOCK(fvp);
199 			return (0);
200 		}
201 
202 		if (ap->a_cnp->cn_namelen == 3 && bcmp(pname, "tty", 3) == 0) {
203 			struct vnode *ttyvp = cttyvp(p);
204 			if (ttyvp == NULL) {
205 				error = ENXIO;
206 				goto bad;
207 			}
208 			error = fdesc_allocvp(Fctty, FD_CTTY, dvp->v_mount, &fvp);
209 			if (error)
210 				goto bad;
211 			*vpp = fvp;
212 			fvp->v_type = VFIFO;
213 			VOP_LOCK(fvp);
214 			return (0);
215 		}
216 
217 		ln = 0;
218 		switch (ap->a_cnp->cn_namelen) {
219 		case 5:
220 			if (bcmp(pname, "stdin", 5) == 0) {
221 				ln = "fd/0";
222 				fd = FD_STDIN;
223 			}
224 			break;
225 		case 6:
226 			if (bcmp(pname, "stdout", 6) == 0) {
227 				ln = "fd/1";
228 				fd = FD_STDOUT;
229 			} else
230 			if (bcmp(pname, "stderr", 6) == 0) {
231 				ln = "fd/2";
232 				fd = FD_STDERR;
233 			}
234 			break;
235 		}
236 
237 		if (ln) {
238 			error = fdesc_allocvp(Flink, fd, dvp->v_mount, &fvp);
239 			if (error)
240 				goto bad;
241 			VTOFDESC(fvp)->fd_link = ln;
242 			*vpp = fvp;
243 			fvp->v_type = VLNK;
244 			VOP_LOCK(fvp);
245 			return (0);
246 		} else {
247 			error = ENOENT;
248 			goto bad;
249 		}
250 
251 		/* FALL THROUGH */
252 
253 	case Fdevfd:
254 		if (ap->a_cnp->cn_namelen == 2 && bcmp(pname, "..", 2) == 0) {
255 			error = fdesc_root(dvp->v_mount, vpp);
256 			return (error);
257 		}
258 
259 		fd = 0;
260 		while (*pname >= '0' && *pname <= '9') {
261 			fd = 10 * fd + *pname++ - '0';
262 			if (fd >= nfiles)
263 				break;
264 		}
265 
266 		if (*pname != '\0') {
267 			error = ENOENT;
268 			goto bad;
269 		}
270 
271 		if (fd >= nfiles || p->p_fd->fd_ofiles[fd] == NULL) {
272 			error = EBADF;
273 			goto bad;
274 		}
275 
276 		error = fdesc_allocvp(Fdesc, FD_DESC+fd, dvp->v_mount, &fvp);
277 		if (error)
278 			goto bad;
279 		VTOFDESC(fvp)->fd_fd = fd;
280 		*vpp = fvp;
281 		return (0);
282 	}
283 
284 bad:;
285 	*vpp = NULL;
286 	return (error);
287 }
288 
289 int
290 fdesc_open(ap)
291 	struct vop_open_args /* {
292 		struct vnode *a_vp;
293 		int  a_mode;
294 		struct ucred *a_cred;
295 		struct proc *a_p;
296 	} */ *ap;
297 {
298 	struct vnode *vp = ap->a_vp;
299 
300 	switch (VTOFDESC(vp)->fd_type) {
301 	case Fdesc:
302 		/*
303 		 * XXX Kludge: set p->p_dupfd to contain the value of the
304 		 * the file descriptor being sought for duplication. The error
305 		 * return ensures that the vnode for this device will be
306 		 * released by vn_open. Open will detect this special error and
307 		 * take the actions in dupfdopen.  Other callers of vn_open or
308 		 * VOP_OPEN will simply report the error.
309 		 */
310 		ap->a_p->p_dupfd = VTOFDESC(vp)->fd_fd;	/* XXX */
311 		return (ENODEV);
312 
313 	case Fctty:
314 		return (cttyopen(devctty, ap->a_mode, 0, ap->a_p));
315 	}
316 
317 	return (0);
318 }
319 
320 static int
321 fdesc_attr(fd, vap, cred, p)
322 	int fd;
323 	struct vattr *vap;
324 	struct ucred *cred;
325 	struct proc *p;
326 {
327 	struct filedesc *fdp = p->p_fd;
328 	struct file *fp;
329 	struct stat stb;
330 	int error;
331 
332 	if (fd >= fdp->fd_nfiles || (fp = fdp->fd_ofiles[fd]) == NULL)
333 		return (EBADF);
334 
335 	switch (fp->f_type) {
336 	case DTYPE_VNODE:
337 		error = VOP_GETATTR((struct vnode *) fp->f_data, vap, cred, p);
338 		if (error == 0 && vap->va_type == VDIR) {
339 			/*
340 			 * directories can cause loops in the namespace,
341 			 * so turn off the 'x' bits to avoid trouble.
342 			 */
343 			vap->va_mode &= ~((VEXEC)|(VEXEC>>3)|(VEXEC>>6));
344 		}
345 		break;
346 
347 	case DTYPE_SOCKET:
348 		error = soo_stat((struct socket *)fp->f_data, &stb);
349 		if (error == 0) {
350 			vattr_null(vap);
351 			vap->va_type = VSOCK;
352 			vap->va_mode = stb.st_mode;
353 			vap->va_nlink = stb.st_nlink;
354 			vap->va_uid = stb.st_uid;
355 			vap->va_gid = stb.st_gid;
356 			vap->va_fsid = stb.st_dev;
357 			vap->va_fileid = stb.st_ino;
358 			vap->va_size = stb.st_size;
359 			vap->va_blocksize = stb.st_blksize;
360 			vap->va_atime = stb.st_atimespec;
361 			vap->va_mtime = stb.st_mtimespec;
362 			vap->va_ctime = stb.st_ctimespec;
363 			vap->va_gen = stb.st_gen;
364 			vap->va_flags = stb.st_flags;
365 			vap->va_rdev = stb.st_rdev;
366 			vap->va_bytes = stb.st_blocks * stb.st_blksize;
367 		}
368 		break;
369 
370 	default:
371 		panic("fdesc attr");
372 		break;
373 	}
374 
375 	return (error);
376 }
377 
378 int
379 fdesc_getattr(ap)
380 	struct vop_getattr_args /* {
381 		struct vnode *a_vp;
382 		struct vattr *a_vap;
383 		struct ucred *a_cred;
384 		struct proc *a_p;
385 	} */ *ap;
386 {
387 	struct vnode *vp = ap->a_vp;
388 	struct vattr *vap = ap->a_vap;
389 	unsigned fd;
390 	int error = 0;
391 
392 	switch (VTOFDESC(vp)->fd_type) {
393 	case Froot:
394 	case Fdevfd:
395 	case Flink:
396 	case Fctty:
397 		bzero((caddr_t) vap, sizeof(*vap));
398 		vattr_null(vap);
399 		vap->va_fileid = VTOFDESC(vp)->fd_ix;
400 
401 		switch (VTOFDESC(vp)->fd_type) {
402 		case Flink:
403 			vap->va_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
404 			vap->va_type = VLNK;
405 			vap->va_nlink = 1;
406 			vap->va_size = strlen(VTOFDESC(vp)->fd_link);
407 			break;
408 
409 		case Fctty:
410 			vap->va_mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH;
411 			vap->va_type = VFIFO;
412 			vap->va_nlink = 1;
413 			vap->va_size = 0;
414 			break;
415 
416 		default:
417 			vap->va_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
418 			vap->va_type = VDIR;
419 			vap->va_nlink = 2;
420 			vap->va_size = DEV_BSIZE;
421 			break;
422 		}
423 		vap->va_uid = 0;
424 		vap->va_gid = 0;
425 		vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
426 		vap->va_blocksize = DEV_BSIZE;
427 		vap->va_atime.ts_sec = boottime.tv_sec;
428 		vap->va_atime.ts_nsec = 0;
429 		vap->va_mtime = vap->va_atime;
430 		vap->va_ctime = vap->va_mtime;
431 		vap->va_gen = 0;
432 		vap->va_flags = 0;
433 		vap->va_rdev = 0;
434 		vap->va_bytes = 0;
435 		break;
436 
437 	case Fdesc:
438 		fd = VTOFDESC(vp)->fd_fd;
439 		error = fdesc_attr(fd, vap, ap->a_cred, ap->a_p);
440 		break;
441 
442 	default:
443 		panic("fdesc_getattr");
444 		break;
445 	}
446 
447 	if (error == 0)
448 		vp->v_type = vap->va_type;
449 
450 	return (error);
451 }
452 
453 int
454 fdesc_setattr(ap)
455 	struct vop_setattr_args /* {
456 		struct vnode *a_vp;
457 		struct vattr *a_vap;
458 		struct ucred *a_cred;
459 		struct proc *a_p;
460 	} */ *ap;
461 {
462 	struct filedesc *fdp = ap->a_p->p_fd;
463 	struct file *fp;
464 	unsigned fd;
465 	int error;
466 
467 	/*
468 	 * Can't mess with the root vnode
469 	 */
470 	switch (VTOFDESC(ap->a_vp)->fd_type) {
471 	case Fdesc:
472 		break;
473 
474 	case Fctty:
475 		return (0);
476 
477 	default:
478 		return (EACCES);
479 	}
480 
481 	fd = VTOFDESC(ap->a_vp)->fd_fd;
482 	if (fd >= fdp->fd_nfiles || (fp = fdp->fd_ofiles[fd]) == NULL) {
483 		return (EBADF);
484 	}
485 
486 	/*
487 	 * Can setattr the underlying vnode, but not sockets!
488 	 */
489 	switch (fp->f_type) {
490 	case DTYPE_VNODE:
491 		error = VOP_SETATTR((struct vnode *) fp->f_data, ap->a_vap, ap->a_cred, ap->a_p);
492 		break;
493 
494 	case DTYPE_SOCKET:
495 		error = 0;
496 		break;
497 
498 	default:
499 		panic("fdesc setattr");
500 		break;
501 	}
502 
503 	return (error);
504 }
505 
506 #define UIO_MX 16
507 
508 static struct dirtmp {
509 	u_long d_fileno;
510 	u_short d_reclen;
511 	u_short d_namlen;
512 	char d_name[8];
513 } rootent[] = {
514 	{ FD_DEVFD, UIO_MX, 2, "fd" },
515 	{ FD_STDIN, UIO_MX, 5, "stdin" },
516 	{ FD_STDOUT, UIO_MX, 6, "stdout" },
517 	{ FD_STDERR, UIO_MX, 6, "stderr" },
518 	{ FD_CTTY, UIO_MX, 3, "tty" },
519 	{ 0 }
520 };
521 
522 int
523 fdesc_readdir(ap)
524 	struct vop_readdir_args /* {
525 		struct vnode *a_vp;
526 		struct uio *a_uio;
527 		struct ucred *a_cred;
528 		int *a_eofflag;
529 		u_long *a_cookies;
530 		int a_ncookies;
531 	} */ *ap;
532 {
533 	struct uio *uio = ap->a_uio;
534 	struct filedesc *fdp;
535 	int i;
536 	int error;
537 
538 	/*
539 	 * We don't allow exporting fdesc mounts, and currently local
540 	 * requests do not need cookies.
541 	 */
542 	if (ap->a_ncookies)
543 		panic("fdesc_readdir: not hungry");
544 
545 	switch (VTOFDESC(ap->a_vp)->fd_type) {
546 	case Fctty:
547 		return (0);
548 
549 	case Fdesc:
550 		return (ENOTDIR);
551 
552 	default:
553 		break;
554 	}
555 
556 	fdp = uio->uio_procp->p_fd;
557 
558 	if (VTOFDESC(ap->a_vp)->fd_type == Froot) {
559 		struct dirent d;
560 		struct dirent *dp = &d;
561 		struct dirtmp *dt;
562 
563 		i = uio->uio_offset / UIO_MX;
564 		error = 0;
565 
566 		while (uio->uio_resid > 0) {
567 			dt = &rootent[i];
568 			if (dt->d_fileno == 0) {
569 				/**eofflagp = 1;*/
570 				break;
571 			}
572 			i++;
573 
574 			switch (dt->d_fileno) {
575 			case FD_CTTY:
576 				if (cttyvp(uio->uio_procp) == NULL)
577 					continue;
578 				break;
579 
580 			case FD_STDIN:
581 			case FD_STDOUT:
582 			case FD_STDERR:
583 				if ((dt->d_fileno-FD_STDIN) >= fdp->fd_nfiles)
584 					continue;
585 				if (fdp->fd_ofiles[dt->d_fileno-FD_STDIN] == NULL)
586 					continue;
587 				break;
588 			}
589 			bzero((caddr_t) dp, UIO_MX);
590 			dp->d_fileno = dt->d_fileno;
591 			dp->d_namlen = dt->d_namlen;
592 			dp->d_type = DT_UNKNOWN;
593 			dp->d_reclen = dt->d_reclen;
594 			bcopy(dt->d_name, dp->d_name, dp->d_namlen+1);
595 			error = uiomove((caddr_t) dp, UIO_MX, uio);
596 			if (error)
597 				break;
598 		}
599 		uio->uio_offset = i * UIO_MX;
600 		return (error);
601 	}
602 
603 	i = uio->uio_offset / UIO_MX;
604 	error = 0;
605 	while (uio->uio_resid > 0) {
606 		if (i >= fdp->fd_nfiles)
607 			break;
608 
609 		if (fdp->fd_ofiles[i] != NULL) {
610 			struct dirent d;
611 			struct dirent *dp = &d;
612 
613 			bzero((caddr_t) dp, UIO_MX);
614 
615 			dp->d_namlen = sprintf(dp->d_name, "%d", i);
616 			dp->d_reclen = UIO_MX;
617 			dp->d_type = DT_UNKNOWN;
618 			dp->d_fileno = i + FD_STDIN;
619 			/*
620 			 * And ship to userland
621 			 */
622 			error = uiomove((caddr_t) dp, UIO_MX, uio);
623 			if (error)
624 				break;
625 		}
626 		i++;
627 	}
628 
629 	uio->uio_offset = i * UIO_MX;
630 	return (error);
631 }
632 
633 int
634 fdesc_readlink(ap)
635 	struct vop_readlink_args /* {
636 		struct vnode *a_vp;
637 		struct uio *a_uio;
638 		struct ucred *a_cred;
639 	} */ *ap;
640 {
641 	struct vnode *vp = ap->a_vp;
642 	int error;
643 
644 	if (vp->v_type != VLNK)
645 		return (EPERM);
646 
647 	if (VTOFDESC(vp)->fd_type == Flink) {
648 		char *ln = VTOFDESC(vp)->fd_link;
649 		error = uiomove(ln, strlen(ln), ap->a_uio);
650 	} else {
651 		error = EOPNOTSUPP;
652 	}
653 
654 	return (error);
655 }
656 
657 int
658 fdesc_read(ap)
659 	struct vop_read_args /* {
660 		struct vnode *a_vp;
661 		struct uio *a_uio;
662 		int  a_ioflag;
663 		struct ucred *a_cred;
664 	} */ *ap;
665 {
666 	int error = EOPNOTSUPP;
667 
668 	switch (VTOFDESC(ap->a_vp)->fd_type) {
669 	case Fctty:
670 		error = cttyread(devctty, ap->a_uio, ap->a_ioflag);
671 		break;
672 
673 	default:
674 		error = EOPNOTSUPP;
675 		break;
676 	}
677 
678 	return (error);
679 }
680 
681 int
682 fdesc_write(ap)
683 	struct vop_write_args /* {
684 		struct vnode *a_vp;
685 		struct uio *a_uio;
686 		int  a_ioflag;
687 		struct ucred *a_cred;
688 	} */ *ap;
689 {
690 	int error = EOPNOTSUPP;
691 
692 	switch (VTOFDESC(ap->a_vp)->fd_type) {
693 	case Fctty:
694 		error = cttywrite(devctty, ap->a_uio, ap->a_ioflag);
695 		break;
696 
697 	default:
698 		error = EOPNOTSUPP;
699 		break;
700 	}
701 
702 	return (error);
703 }
704 
705 int
706 fdesc_ioctl(ap)
707 	struct vop_ioctl_args /* {
708 		struct vnode *a_vp;
709 		u_long a_command;
710 		caddr_t  a_data;
711 		int  a_fflag;
712 		struct ucred *a_cred;
713 		struct proc *a_p;
714 	} */ *ap;
715 {
716 	int error = EOPNOTSUPP;
717 
718 	switch (VTOFDESC(ap->a_vp)->fd_type) {
719 	case Fctty:
720 		error = cttyioctl(devctty, ap->a_command, ap->a_data,
721 					ap->a_fflag, ap->a_p);
722 		break;
723 
724 	default:
725 		error = EOPNOTSUPP;
726 		break;
727 	}
728 
729 	return (error);
730 }
731 
732 int
733 fdesc_select(ap)
734 	struct vop_select_args /* {
735 		struct vnode *a_vp;
736 		int  a_which;
737 		int  a_fflags;
738 		struct ucred *a_cred;
739 		struct proc *a_p;
740 	} */ *ap;
741 {
742 	int error = EOPNOTSUPP;
743 
744 	switch (VTOFDESC(ap->a_vp)->fd_type) {
745 	case Fctty:
746 		error = cttyselect(devctty, ap->a_fflags, ap->a_p);
747 		break;
748 
749 	default:
750 		error = EOPNOTSUPP;
751 		break;
752 	}
753 
754 	return (error);
755 }
756 
757 int
758 fdesc_inactive(ap)
759 	struct vop_inactive_args /* {
760 		struct vnode *a_vp;
761 	} */ *ap;
762 {
763 	struct vnode *vp = ap->a_vp;
764 
765 	/*
766 	 * Clear out the v_type field to avoid
767 	 * nasty things happening in vgone().
768 	 */
769 	vp->v_type = VNON;
770 	return (0);
771 }
772 
773 int
774 fdesc_reclaim(ap)
775 	struct vop_reclaim_args /* {
776 		struct vnode *a_vp;
777 	} */ *ap;
778 {
779 	struct vnode *vp = ap->a_vp;
780 	struct fdescnode *fd = VTOFDESC(vp);
781 
782 	LIST_REMOVE(fd, fd_hash);
783 	FREE(vp->v_data, M_TEMP);
784 	vp->v_data = 0;
785 
786 	return (0);
787 }
788 
789 /*
790  * Return POSIX pathconf information applicable to special devices.
791  */
792 fdesc_pathconf(ap)
793 	struct vop_pathconf_args /* {
794 		struct vnode *a_vp;
795 		int a_name;
796 		register_t *a_retval;
797 	} */ *ap;
798 {
799 
800 	switch (ap->a_name) {
801 	case _PC_LINK_MAX:
802 		*ap->a_retval = LINK_MAX;
803 		return (0);
804 	case _PC_MAX_CANON:
805 		*ap->a_retval = MAX_CANON;
806 		return (0);
807 	case _PC_MAX_INPUT:
808 		*ap->a_retval = MAX_INPUT;
809 		return (0);
810 	case _PC_PIPE_BUF:
811 		*ap->a_retval = PIPE_BUF;
812 		return (0);
813 	case _PC_CHOWN_RESTRICTED:
814 		*ap->a_retval = 1;
815 		return (0);
816 	case _PC_VDISABLE:
817 		*ap->a_retval = _POSIX_VDISABLE;
818 		return (0);
819 	default:
820 		return (EINVAL);
821 	}
822 	/* NOTREACHED */
823 }
824 
825 /*
826  * Print out the contents of a /dev/fd vnode.
827  */
828 /* ARGSUSED */
829 int
830 fdesc_print(ap)
831 	struct vop_print_args /* {
832 		struct vnode *a_vp;
833 	} */ *ap;
834 {
835 
836 	printf("tag VT_NON, fdesc vnode\n");
837 	return (0);
838 }
839 
840 /*void*/
841 int
842 fdesc_vfree(ap)
843 	struct vop_vfree_args /* {
844 		struct vnode *a_pvp;
845 		ino_t a_ino;
846 		int a_mode;
847 	} */ *ap;
848 {
849 
850 	return (0);
851 }
852 
853 /*
854  * /dev/fd vnode unsupported operation
855  */
856 int
857 fdesc_enotsupp()
858 {
859 
860 	return (EOPNOTSUPP);
861 }
862 
863 /*
864  * /dev/fd "should never get here" operation
865  */
866 int
867 fdesc_badop()
868 {
869 
870 	panic("fdesc: bad op");
871 	/* NOTREACHED */
872 }
873 
874 /*
875  * /dev/fd vnode null operation
876  */
877 int
878 fdesc_nullop()
879 {
880 
881 	return (0);
882 }
883 
884 #define fdesc_create ((int (*) __P((struct  vop_create_args *)))fdesc_enotsupp)
885 #define fdesc_mknod ((int (*) __P((struct  vop_mknod_args *)))fdesc_enotsupp)
886 #define fdesc_close ((int (*) __P((struct  vop_close_args *)))nullop)
887 #define fdesc_access ((int (*) __P((struct  vop_access_args *)))nullop)
888 #define fdesc_mmap ((int (*) __P((struct  vop_mmap_args *)))fdesc_enotsupp)
889 #define fdesc_fsync ((int (*) __P((struct  vop_fsync_args *)))nullop)
890 #define fdesc_seek ((int (*) __P((struct  vop_seek_args *)))nullop)
891 #define fdesc_remove ((int (*) __P((struct  vop_remove_args *)))fdesc_enotsupp)
892 #define fdesc_link ((int (*) __P((struct  vop_link_args *)))fdesc_enotsupp)
893 #define fdesc_rename ((int (*) __P((struct  vop_rename_args *)))fdesc_enotsupp)
894 #define fdesc_mkdir ((int (*) __P((struct  vop_mkdir_args *)))fdesc_enotsupp)
895 #define fdesc_rmdir ((int (*) __P((struct  vop_rmdir_args *)))fdesc_enotsupp)
896 #define fdesc_symlink ((int (*) __P((struct vop_symlink_args *)))fdesc_enotsupp)
897 #define fdesc_abortop ((int (*) __P((struct  vop_abortop_args *)))nullop)
898 #define fdesc_lock ((int (*) __P((struct  vop_lock_args *)))nullop)
899 #define fdesc_unlock ((int (*) __P((struct  vop_unlock_args *)))nullop)
900 #define fdesc_bmap ((int (*) __P((struct  vop_bmap_args *)))fdesc_badop)
901 #define fdesc_strategy ((int (*) __P((struct  vop_strategy_args *)))fdesc_badop)
902 #define fdesc_islocked ((int (*) __P((struct  vop_islocked_args *)))nullop)
903 #define fdesc_advlock ((int (*) __P((struct vop_advlock_args *)))fdesc_enotsupp)
904 #define fdesc_blkatoff \
905 	((int (*) __P((struct  vop_blkatoff_args *)))fdesc_enotsupp)
906 #define fdesc_vget ((int (*) __P((struct  vop_vget_args *)))fdesc_enotsupp)
907 #define fdesc_valloc ((int(*) __P(( \
908 		struct vnode *pvp, \
909 		int mode, \
910 		struct ucred *cred, \
911 		struct vnode **vpp))) fdesc_enotsupp)
912 #define fdesc_truncate \
913 	((int (*) __P((struct  vop_truncate_args *)))fdesc_enotsupp)
914 #define fdesc_update ((int (*) __P((struct  vop_update_args *)))fdesc_enotsupp)
915 #define fdesc_bwrite ((int (*) __P((struct  vop_bwrite_args *)))fdesc_enotsupp)
916 
917 int (**fdesc_vnodeop_p)();
918 struct vnodeopv_entry_desc fdesc_vnodeop_entries[] = {
919 	{ &vop_default_desc, vn_default_error },
920 	{ &vop_lookup_desc, fdesc_lookup },	/* lookup */
921 	{ &vop_create_desc, fdesc_create },	/* create */
922 	{ &vop_mknod_desc, fdesc_mknod },	/* mknod */
923 	{ &vop_open_desc, fdesc_open },		/* open */
924 	{ &vop_close_desc, fdesc_close },	/* close */
925 	{ &vop_access_desc, fdesc_access },	/* access */
926 	{ &vop_getattr_desc, fdesc_getattr },	/* getattr */
927 	{ &vop_setattr_desc, fdesc_setattr },	/* setattr */
928 	{ &vop_read_desc, fdesc_read },		/* read */
929 	{ &vop_write_desc, fdesc_write },	/* write */
930 	{ &vop_ioctl_desc, fdesc_ioctl },	/* ioctl */
931 	{ &vop_select_desc, fdesc_select },	/* select */
932 	{ &vop_mmap_desc, fdesc_mmap },		/* mmap */
933 	{ &vop_fsync_desc, fdesc_fsync },	/* fsync */
934 	{ &vop_seek_desc, fdesc_seek },		/* seek */
935 	{ &vop_remove_desc, fdesc_remove },	/* remove */
936 	{ &vop_link_desc, fdesc_link },		/* link */
937 	{ &vop_rename_desc, fdesc_rename },	/* rename */
938 	{ &vop_mkdir_desc, fdesc_mkdir },	/* mkdir */
939 	{ &vop_rmdir_desc, fdesc_rmdir },	/* rmdir */
940 	{ &vop_symlink_desc, fdesc_symlink },	/* symlink */
941 	{ &vop_readdir_desc, fdesc_readdir },	/* readdir */
942 	{ &vop_readlink_desc, fdesc_readlink },	/* readlink */
943 	{ &vop_abortop_desc, fdesc_abortop },	/* abortop */
944 	{ &vop_inactive_desc, fdesc_inactive },	/* inactive */
945 	{ &vop_reclaim_desc, fdesc_reclaim },	/* reclaim */
946 	{ &vop_lock_desc, fdesc_lock },		/* lock */
947 	{ &vop_unlock_desc, fdesc_unlock },	/* unlock */
948 	{ &vop_bmap_desc, fdesc_bmap },		/* bmap */
949 	{ &vop_strategy_desc, fdesc_strategy },	/* strategy */
950 	{ &vop_print_desc, fdesc_print },	/* print */
951 	{ &vop_islocked_desc, fdesc_islocked },	/* islocked */
952 	{ &vop_pathconf_desc, fdesc_pathconf },	/* pathconf */
953 	{ &vop_advlock_desc, fdesc_advlock },	/* advlock */
954 	{ &vop_blkatoff_desc, fdesc_blkatoff },	/* blkatoff */
955 	{ &vop_valloc_desc, fdesc_valloc },	/* valloc */
956 	{ &vop_vfree_desc, fdesc_vfree },	/* vfree */
957 	{ &vop_truncate_desc, fdesc_truncate },	/* truncate */
958 	{ &vop_update_desc, fdesc_update },	/* update */
959 	{ &vop_bwrite_desc, fdesc_bwrite },	/* bwrite */
960 	{ (struct vnodeop_desc*)NULL, (int(*)())NULL }
961 };
962 struct vnodeopv_desc fdesc_vnodeop_opv_desc =
963 	{ &fdesc_vnodeop_p, fdesc_vnodeop_entries };
964