xref: /xnu-8792.61.2/bsd/miscfs/devfs/devfs_fdesc_support.c (revision 42e220869062b56f8d7d0726fd4c88954f87902c)
1 /*
2  * Copyright (c) 2000-2019 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
29 /*
30  * Copyright (c) 1992, 1993
31  *	The Regents of the University of California.  All rights reserved.
32  *
33  * This code is derived from software donated to Berkeley by
34  * Jan-Simon Pendry.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. All advertising materials mentioning features or use of this software
45  *    must display the following acknowledgement:
46  *	This product includes software developed by the University of
47  *	California, Berkeley and its contributors.
48  * 4. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  *	@(#)fdesc_vnops.c	8.17 (Berkeley) 5/22/95
65  *
66  */
67 
68 /*
69  * /dev/fd Filesystem
70  */
71 
72 #include <sys/param.h>
73 #include <sys/systm.h>
74 #include <sys/types.h>
75 #include <sys/time.h>
76 #include <sys/proc_internal.h>
77 #include <sys/kernel.h> /* boottime */
78 #include <sys/resourcevar.h>
79 #include <sys/filedesc.h>
80 #include <sys/kauth.h>
81 #include <sys/vnode_internal.h>
82 #include <sys/malloc.h>
83 #include <sys/file_internal.h>
84 #include <sys/stat.h>
85 #include <sys/mount_internal.h>
86 #include <sys/namei.h>
87 #include <sys/dirent.h>
88 #include <sys/ubc.h>
89 #include <sys/socketvar.h>
90 #include <sys/pipe.h>
91 #include <sys/uio_internal.h>
92 #include <vfs/vfs_support.h>
93 #include <pexpert/pexpert.h>
94 #include <miscfs/devfs/fdesc.h>
95 #include <miscfs/devfs/devfs.h>
96 #include <miscfs/devfs/devfsdefs.h>
97 
98 #define FDL_WANT        0x01
99 #define FDL_LOCKED      0x02
100 static int fdcache_lock;
101 
102 
103 #if (FD_STDIN != FD_STDOUT - 1) || (FD_STDOUT != FD_STDERR - 1)
104 FD_STDIN, FD_STDOUT, FD_STDERR must be a sequence n, n + 1, n + 2
105 #endif
106 
107 #define NFDCACHE 3
108 
109 #define FD_NHASH(ix) \
110 	(&fdhashtbl[(ix) & fdhash])
111 LIST_HEAD(fdhashhead, fdescnode) * fdhashtbl;
112 u_long fdhash;
113 
114 static int fdesc_attr(int fd, struct vnode_attr *vap, vfs_context_t a_context);
115 
116 static LCK_GRP_DECLARE(fdesc_lckgrp, "fdesc");
117 static LCK_MTX_DECLARE(fdesc_mtx, &fdesc_lckgrp);
118 
119 static void
fdesc_lock(void)120 fdesc_lock(void)
121 {
122 	lck_mtx_lock(&fdesc_mtx);
123 }
124 
125 static void
fdesc_unlock(void)126 fdesc_unlock(void)
127 {
128 	lck_mtx_unlock(&fdesc_mtx);
129 }
130 
131 
132 /*
133  * Initialise cache headers, create the devfs node
134  */
135 int
devfs_fdesc_init()136 devfs_fdesc_init()
137 {
138 	int error = 0;
139 	devnode_t *rootdir = dev_root->de_dnp;
140 	devdirent_t *direntp;
141 
142 	/* XXX Make sure you have the right path... */
143 	fdhashtbl = hashinit(NFDCACHE, M_CACHE, &fdhash);
144 
145 	DEVFS_LOCK();
146 	dev_add_entry("fd", rootdir, DEV_DEVFD, NULL, NULL, NULL, &direntp);
147 	devfs_fdesc_makelinks();
148 	DEVFS_UNLOCK();
149 
150 	return error;
151 }
152 
153 /*
154  * Called during early startup, no need to synchronize
155  */
156 int
devfs_fdesc_makelinks()157 devfs_fdesc_makelinks()
158 {
159 	int error = 0;
160 	devdirent_t *stdin_ent = NULL, *stdout_ent = NULL, *stderr_ent = NULL;
161 	devnode_t *root_devnode = dev_root->de_dnp;
162 
163 	/* We do this ugliness to get around some "const" warnings */
164 	char in[] = "stdin";
165 	char out[] = "stdout";
166 	char err[] = "stderr";
167 	char zero[] = "fd/0";
168 	char one[] = "fd/1";
169 	char two[] = "fd/2";
170 
171 	if ((error = devfs_make_symlink(root_devnode, in, 0555, zero, &stdin_ent))) {
172 		printf("Couldn't make stdin, err %d.\n", error);
173 		goto bad;
174 	}
175 
176 	if ((error = devfs_make_symlink(root_devnode, out, 0555, one, &stdout_ent))) {
177 		printf("Couldn't make stdout, err %d.\n", error);
178 		goto bad;
179 	}
180 
181 	if ((error = devfs_make_symlink(root_devnode, err, 0555, two, &stderr_ent))) {
182 		printf("Couldn't make stderr, err %d.\n", error);
183 		goto bad;
184 	}
185 
186 	return 0;
187 
188 bad:
189 	if (stdin_ent) {
190 		dev_free_name(stdin_ent);
191 	}
192 	if (stdout_ent) {
193 		dev_free_name(stdout_ent);
194 	}
195 	if (stderr_ent) {
196 		dev_free_name(stderr_ent);
197 	}
198 
199 	return error;
200 }
201 
202 int
fdesc_allocvp(fdntype ftype,int ix,struct mount * mp,struct vnode ** vpp,enum vtype vtype,int fdno)203 fdesc_allocvp(fdntype ftype, int ix, struct mount *mp, struct vnode **vpp, enum vtype vtype, int fdno)
204 {
205 	struct fdhashhead *fc;
206 	struct fdescnode *fd;
207 	int error = 0;
208 	int vid = 0;
209 	struct vnode_fsparam vfsp;
210 	struct vnode *vp;
211 
212 	fdesc_lock();
213 
214 	fc = FD_NHASH(ix);
215 loop:
216 	for (fd = fc->lh_first; fd != 0; fd = fd->fd_hash.le_next) {
217 		if (fd->fd_ix == ix && vnode_mount(fd->fd_vnode) == mp) {
218 			vid = vnode_vid(fd->fd_vnode);
219 			vp = fd->fd_vnode;
220 			vnode_hold(vp);
221 			fdesc_unlock();
222 
223 			if (vnode_getwithvid(vp, vid)) {
224 				vnode_drop(vp);
225 				fdesc_lock();
226 				goto loop;
227 			}
228 
229 			vnode_drop(vp);
230 			*vpp = vp;
231 			(*vpp)->v_type = (uint16_t)vtype;
232 
233 			return error;
234 		}
235 	}
236 
237 	/* Only one thread can add to the hash at a time */
238 	if (fdcache_lock & FDL_LOCKED) {
239 		fdcache_lock |= FDL_WANT;
240 		msleep((caddr_t) &fdcache_lock, &fdesc_mtx, PINOD, "fdesc_allocvp", NULL);
241 		goto loop;
242 	}
243 
244 	fdcache_lock |= FDL_LOCKED;
245 	fdesc_unlock();
246 
247 	fd = kalloc_type(struct fdescnode, Z_WAITOK);
248 
249 	vfsp.vnfs_mp = mp;
250 	vfsp.vnfs_vtype = vtype;
251 	vfsp.vnfs_str = "fdesc";
252 	vfsp.vnfs_dvp = NULL;
253 	vfsp.vnfs_fsnode = fd;
254 	vfsp.vnfs_cnp = NULL;
255 	vfsp.vnfs_vops = fdesc_vnodeop_p;
256 	vfsp.vnfs_rdev = 0;
257 	vfsp.vnfs_filesize = 0;
258 	vfsp.vnfs_flags = VNFS_NOCACHE | VNFS_CANTCACHE;
259 	vfsp.vnfs_marksystem = 0;
260 	vfsp.vnfs_markroot = 0;
261 
262 	error = vnode_create_ext(VNCREATE_FLAVOR, VCREATESIZE, &vfsp, vpp,
263 	    VNODE_CREATE_DEFAULT);
264 	if (error) {
265 		kfree_type(struct fdescnode, fd);
266 		fdesc_lock();
267 		goto out;
268 	}
269 
270 	(*vpp)->v_tag = VT_FDESC;
271 	fd->fd_vnode = *vpp;
272 	fd->fd_type = ftype;
273 	fd->fd_fd = fdno;
274 	fd->fd_link = NULL;
275 	fd->fd_ix = ix;
276 
277 	fdesc_lock();
278 
279 	LIST_INSERT_HEAD(fc, fd, fd_hash);
280 out:
281 	/* Hold the lock when we get here */
282 	fdcache_lock &= ~FDL_LOCKED;
283 
284 	if (fdcache_lock & FDL_WANT) {
285 		fdcache_lock &= ~FDL_WANT;
286 		wakeup((caddr_t) &fdcache_lock);
287 	}
288 
289 	fdesc_unlock();
290 
291 	return error;
292 }
293 
294 /*
295  * vp is the current namei directory
296  * ndp is the name to locate in that directory...
297  *
298  * This vnop should only be called on the special directory /dev/fd.
299  */
300 int
devfs_devfd_lookup(struct vnop_lookup_args * ap)301 devfs_devfd_lookup(struct vnop_lookup_args *ap)
302 {
303 	struct vnode **vpp = ap->a_vpp;
304 	struct vnode *dvp = ap->a_dvp;
305 	struct componentname *cnp = ap->a_cnp;
306 	char *pname = cnp->cn_nameptr;
307 	struct proc *p = vfs_context_proc(ap->a_context);
308 	int numfiles = p->p_fd.fd_nfiles;
309 	int fd;
310 	int error;
311 	struct vnode *fvp;
312 
313 	if (cnp->cn_namelen == 1 && *pname == '.') {
314 		*vpp = dvp;
315 
316 		if ((error = vnode_get(dvp))) {
317 			goto bad;
318 		}
319 		return 0;
320 	}
321 
322 	fd = 0;
323 	while (*pname >= '0' && *pname <= '9') {
324 		if (os_mul_and_add_overflow(fd, 10, *pname++ - '0', &fd)) {
325 			break;
326 		}
327 	}
328 
329 	if (*pname != '\0') {
330 		error = ENOENT;
331 		goto bad;
332 	}
333 
334 	if (fd < 0 || fd >= numfiles ||
335 	    *fdfile(p, fd) == NULL ||
336 	    (*fdflags(p, fd) & UF_RESERVED)) {
337 		error = EBADF;
338 		goto bad;
339 	}
340 
341 	error = fdesc_allocvp(Fdesc, FD_DESC + fd, dvp->v_mount, &fvp, VNON, fd);
342 	if (error) {
343 		goto bad;
344 	}
345 	*vpp = fvp;
346 	return 0;
347 
348 bad:
349 	*vpp = NULL;
350 	return error;
351 }
352 
353 int
fdesc_open(struct vnop_open_args * ap)354 fdesc_open(struct vnop_open_args *ap)
355 {
356 	struct vnode *vp = ap->a_vp;
357 	thread_t thr = vfs_context_thread(ap->a_context);
358 	uthread_t uu;
359 	int error = 0;
360 
361 	if (thr == NULL) {
362 		return EINVAL;
363 	}
364 
365 	uu = get_bsdthread_info(thr);
366 
367 	switch (VTOFDESC(vp)->fd_type) {
368 	case Fdesc:
369 		/*
370 		 * XXX Kludge: set uu->uu_dupfd to contain the value of the
371 		 * the file descriptor being sought for duplication. The error
372 		 * return ensures that the vnode for this device will be
373 		 * released by vn_open. Open will detect this special error and
374 		 * take the actions in dupfdopen.  Other callers of vn_open or
375 		 * vnop_open will simply report the error.
376 		 */
377 		uu->uu_dupfd = VTOFDESC(vp)->fd_fd;     /* XXX */
378 		error = ENODEV;
379 		break;
380 	default:
381 		panic("Invalid type for fdesc node!");
382 		break;
383 	}
384 
385 	return error;
386 }
387 
388 static int
fdesc_attr(int fd,struct vnode_attr * vap,vfs_context_t a_context)389 fdesc_attr(int fd, struct vnode_attr *vap, vfs_context_t a_context)
390 {
391 	struct fileproc *fp;
392 	struct proc *p = vfs_context_proc(a_context);
393 	struct stat stb;
394 	int error;
395 
396 	if ((error = fp_lookup(p, fd, &fp, 0))) {
397 		return error;
398 	}
399 	switch (FILEGLOB_DTYPE(fp->fp_glob)) {
400 	case DTYPE_VNODE:
401 		if ((error = vnode_getwithref((struct vnode *)fp_get_data(fp))) != 0) {
402 			break;
403 		}
404 		if ((error = vnode_authorize((struct vnode *)fp_get_data(fp),
405 		    NULL,
406 		    KAUTH_VNODE_READ_ATTRIBUTES | KAUTH_VNODE_READ_SECURITY,
407 		    a_context)) == 0) {
408 			error = vnode_getattr((struct vnode *)fp_get_data(fp), vap, a_context);
409 		}
410 		if (error == 0 && vap->va_type == VDIR) {
411 			/*
412 			 * directories can cause loops in the namespace,
413 			 * so turn off the 'x' bits to avoid trouble.
414 			 *
415 			 * XXX ACLs break this, of course
416 			 */
417 			vap->va_mode &= ~((VEXEC) | (VEXEC >> 3) | (VEXEC >> 6));
418 		}
419 		(void)vnode_put((struct vnode *)fp_get_data(fp));
420 		break;
421 
422 	case DTYPE_SOCKET:
423 	case DTYPE_PIPE:
424 #if SOCKETS
425 		if (FILEGLOB_DTYPE(fp->fp_glob) == DTYPE_SOCKET) {
426 			error = soo_stat((struct socket *)fp_get_data(fp), (void *)&stb, 0);
427 		} else
428 #endif /* SOCKETS */
429 		error = pipe_stat((struct pipe *)fp_get_data(fp), (void *)&stb, 0);
430 
431 		if (error == 0) {
432 			if (FILEGLOB_DTYPE(fp->fp_glob) == DTYPE_SOCKET) {
433 				VATTR_RETURN(vap, va_type, VSOCK);
434 			} else {
435 				VATTR_RETURN(vap, va_type, VFIFO);
436 			}
437 
438 			VATTR_RETURN(vap, va_mode, stb.st_mode);
439 			VATTR_RETURN(vap, va_nlink, stb.st_nlink);
440 			VATTR_RETURN(vap, va_uid, stb.st_uid);
441 			VATTR_RETURN(vap, va_gid, stb.st_gid);
442 			VATTR_RETURN(vap, va_fsid, stb.st_dev);
443 			VATTR_RETURN(vap, va_fileid, stb.st_ino);
444 			VATTR_RETURN(vap, va_data_size, stb.st_size);
445 			VATTR_RETURN(vap, va_access_time, stb.st_atimespec);
446 			VATTR_RETURN(vap, va_modify_time, stb.st_mtimespec);
447 			VATTR_RETURN(vap, va_change_time, stb.st_ctimespec);
448 			VATTR_RETURN(vap, va_gen, stb.st_gen);
449 			VATTR_RETURN(vap, va_flags, stb.st_flags);
450 			VATTR_RETURN(vap, va_rdev, stb.st_rdev);
451 			VATTR_RETURN(vap, va_total_alloc, stb.st_blocks * stb.st_blksize);
452 			VATTR_RETURN(vap, va_acl, NULL);
453 		}
454 		break;
455 
456 	default:
457 		error = EBADF;
458 	}
459 
460 	fp_drop(p, fd, fp, 0);
461 	return error;
462 }
463 
464 int
fdesc_getattr(struct vnop_getattr_args * ap)465 fdesc_getattr(struct vnop_getattr_args *ap)
466 {
467 	struct vnode *vp = ap->a_vp;
468 	struct vnode_attr *vap = ap->a_vap;
469 	unsigned fd;
470 	int error = 0;
471 
472 	switch (VTOFDESC(vp)->fd_type) {
473 	case Fdesc:
474 		fd = VTOFDESC(vp)->fd_fd;
475 		error = fdesc_attr(fd, vap, ap->a_context);
476 		break;
477 
478 	default:
479 		panic("Invalid type for an fdesc node!");
480 		break;
481 	}
482 
483 	/*
484 	 * Yes, we do this without locking, but this value is always just
485 	 * a snapshot.
486 	 */
487 	if (error == 0) {
488 		vp->v_type = (uint16_t)vap->va_type;
489 
490 		/* We need an inactive to reset type to VNON */
491 		vnode_setneedinactive(vp);
492 	}
493 
494 	return error;
495 }
496 
497 int
fdesc_setattr(struct vnop_setattr_args * ap)498 fdesc_setattr(struct vnop_setattr_args *ap)
499 {
500 	struct fileproc *fp;
501 	unsigned fd;
502 	int error;
503 	struct proc * p = vfs_context_proc(ap->a_context);
504 
505 	/*
506 	 * Can't mess with the root vnode
507 	 */
508 	switch (VTOFDESC(ap->a_vp)->fd_type) {
509 	case Fdesc:
510 		break;
511 	default:
512 		panic("Invalid type for an fdesc node!");
513 		return EACCES;
514 	}
515 
516 	fd = VTOFDESC(ap->a_vp)->fd_fd;
517 	if ((error = fp_lookup(vfs_context_proc(ap->a_context), fd, &fp, 0))) {
518 		return error;
519 	}
520 
521 	/*
522 	 * Can setattr the underlying vnode, but not sockets!
523 	 */
524 	switch (FILEGLOB_DTYPE(fp->fp_glob)) {
525 	case DTYPE_VNODE:
526 	{
527 		if ((error = vnode_getwithref((struct vnode *)fp_get_data(fp))) != 0) {
528 			break;
529 		}
530 		error = vnode_setattr((struct vnode *)fp_get_data(fp), ap->a_vap, ap->a_context);
531 		(void)vnode_put((struct vnode *)fp_get_data(fp));
532 		break;
533 	}
534 
535 	case DTYPE_SOCKET:
536 	case DTYPE_PIPE:
537 		error = 0;
538 		break;
539 
540 	default:
541 		error = EBADF;
542 		break;
543 	}
544 
545 	fp_drop(p, fd, fp, 0);
546 	return error;
547 }
548 
549 #define UIO_MX 16
550 
551 /*
552  *  static struct dirtmp {
553  *       u_int32_t d_fileno;
554  *       u_short d_reclen;
555  *       u_short d_namlen;
556  *       char d_name[8];
557  *  } rootent[] = {
558  *       { FD_DEVFD, UIO_MX, 2, "fd" },
559  *       { FD_STDIN, UIO_MX, 5, "stdin" },
560  *       { FD_STDOUT, UIO_MX, 6, "stdout" },
561  *       { FD_STDERR, UIO_MX, 6, "stderr" },
562  *       { 0, 0, 0, "" }
563  *  };
564  */
565 
566 /* Only called on /dev/fd */
567 int
devfs_devfd_readdir(struct vnop_readdir_args * ap)568 devfs_devfd_readdir(struct vnop_readdir_args *ap)
569 {
570 	struct uio *uio = ap->a_uio;
571 	struct proc *p = current_proc();
572 	off_t i;
573 	int error;
574 
575 	/*
576 	 * We don't allow exporting fdesc mounts, and currently local
577 	 * requests do not need cookies.
578 	 */
579 	if (ap->a_flags & (VNODE_READDIR_EXTENDED | VNODE_READDIR_REQSEEKOFF)) {
580 		return EINVAL;
581 	}
582 
583 	/*
584 	 * There needs to be space for at least one entry.
585 	 */
586 	if (uio_resid(uio) < UIO_MX) {
587 		return EINVAL;
588 	}
589 
590 	i = uio->uio_offset / UIO_MX;
591 	error = 0;
592 	while (uio_resid(uio) >= UIO_MX) {
593 		if (i >= p->p_fd.fd_nfiles || i < 0) {
594 			break;
595 		}
596 
597 		if (*fdfile(p, i) != NULL && !(*fdflags(p, i) & UF_RESERVED)) {
598 			struct dirent d;
599 			struct dirent *dp = &d;
600 
601 			bzero((caddr_t) dp, UIO_MX);
602 
603 			dp->d_namlen = (__uint8_t)scnprintf(dp->d_name, sizeof(dp->d_name),
604 			    "%lld", i);
605 			dp->d_reclen = UIO_MX;
606 			dp->d_type = DT_UNKNOWN;
607 			dp->d_fileno = (ino_t)i + FD_STDIN;
608 			/*
609 			 * And ship to userland
610 			 */
611 			error = uiomove((caddr_t) dp, UIO_MX, uio);
612 			if (error) {
613 				break;
614 			}
615 		}
616 		i++;
617 	}
618 
619 	uio->uio_offset = i * UIO_MX;
620 	return error;
621 }
622 
623 int
fdesc_read(__unused struct vnop_read_args * ap)624 fdesc_read(__unused struct vnop_read_args *ap)
625 {
626 	return ENOTSUP;
627 }
628 
629 int
fdesc_write(__unused struct vnop_write_args * ap)630 fdesc_write(__unused struct vnop_write_args *ap)
631 {
632 	return ENOTSUP;
633 }
634 
635 int
fdesc_ioctl(__unused struct vnop_ioctl_args * ap)636 fdesc_ioctl(__unused struct vnop_ioctl_args *ap)
637 {
638 	return ENOTSUP;
639 }
640 
641 int
fdesc_select(__unused struct vnop_select_args * ap)642 fdesc_select(__unused struct vnop_select_args *ap)
643 {
644 	return ENOTSUP;
645 }
646 
647 int
fdesc_inactive(struct vnop_inactive_args * ap)648 fdesc_inactive(struct vnop_inactive_args *ap)
649 {
650 	struct vnode *vp = ap->a_vp;
651 
652 	/*
653 	 * Clear out the v_type field to avoid
654 	 * nasty things happening in vgone().
655 	 */
656 	vp->v_type = VNON;
657 
658 	return 0;
659 }
660 
661 int
fdesc_reclaim(struct vnop_reclaim_args * ap)662 fdesc_reclaim(struct vnop_reclaim_args *ap)
663 {
664 	struct vnode *vp = ap->a_vp;
665 	struct fdescnode *fd = VTOFDESC(vp);
666 
667 	fdesc_lock();
668 
669 	LIST_REMOVE(fd, fd_hash);
670 	kfree_type(struct fdescnode, vp->v_data);
671 
672 	fdesc_unlock();
673 
674 	return 0;
675 }
676 
677 /*
678  * Return POSIX pathconf information applicable to special devices.
679  */
680 int
fdesc_pathconf(struct vnop_pathconf_args * ap)681 fdesc_pathconf(struct vnop_pathconf_args *ap)
682 {
683 	switch (ap->a_name) {
684 	case _PC_LINK_MAX:
685 		*ap->a_retval = LINK_MAX;
686 		return 0;
687 	case _PC_MAX_CANON:
688 		*ap->a_retval = MAX_CANON;
689 		return 0;
690 	case _PC_MAX_INPUT:
691 		*ap->a_retval = MAX_INPUT;
692 		return 0;
693 	case _PC_PIPE_BUF:
694 		*ap->a_retval = PIPE_BUF;
695 		return 0;
696 	case _PC_CHOWN_RESTRICTED:
697 		*ap->a_retval = 200112;         /* _POSIX_CHOWN_RESTRICTED */
698 		return 0;
699 	case _PC_VDISABLE:
700 		*ap->a_retval = _POSIX_VDISABLE;
701 		return 0;
702 	default:
703 		return EINVAL;
704 	}
705 	/* NOTREACHED */
706 }
707 
708 /*
709  * /dev/fd "should never get here" operation
710  */
711 int
fdesc_badop(void)712 fdesc_badop(void)
713 {
714 	return ENOTSUP;
715 	/* NOTREACHED */
716 }
717 
718 #define VOPFUNC int (*)(void *)
719 
720 #define fdesc_revoke nop_revoke
721 #define fdesc_strategy (void (*)(void))fdesc_badop
722 
723 #define fdesc_nullop (void (*)(void ))nullop
724 #define fdesc_error (void (*)(void ))vn_default_error
725 #define fdesc_notsupp (void (*)(void ))eopnotsupp
726 
727 int(**fdesc_vnodeop_p)(void *);
728 const struct vnodeopv_entry_desc devfs_fdesc_vnodeop_entries[] = {
729 	{ .opve_op = &vnop_default_desc, .opve_impl = (VOPFUNC)fdesc_error },
730 	{ .opve_op = &vnop_lookup_desc, .opve_impl = (VOPFUNC)fdesc_error},        /* lookup */
731 	{ .opve_op = &vnop_create_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },   /* create */
732 	{ .opve_op = &vnop_mknod_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },     /* mknod */
733 	{ .opve_op = &vnop_open_desc, .opve_impl = (VOPFUNC)fdesc_open },       /* open */
734 	{ .opve_op = &vnop_close_desc, .opve_impl = (VOPFUNC)fdesc_nullop },     /* close */
735 	{ .opve_op = &vnop_access_desc, .opve_impl = (VOPFUNC)fdesc_nullop },   /* access */
736 	{ .opve_op = &vnop_getattr_desc, .opve_impl = (VOPFUNC)fdesc_getattr }, /* getattr */
737 	{ .opve_op = &vnop_setattr_desc, .opve_impl = (VOPFUNC)fdesc_setattr }, /* setattr */
738 	{ .opve_op = &vnop_read_desc, .opve_impl = (VOPFUNC)fdesc_read },       /* read */
739 	{ .opve_op = &vnop_write_desc, .opve_impl = (VOPFUNC)fdesc_write },     /* write */
740 	{ .opve_op = &vnop_ioctl_desc, .opve_impl = (VOPFUNC)fdesc_ioctl },     /* ioctl */
741 	{ .opve_op = &vnop_select_desc, .opve_impl = (VOPFUNC)fdesc_select },   /* select */
742 	{ .opve_op = &vnop_revoke_desc, .opve_impl = (VOPFUNC)fdesc_revoke },   /* revoke */
743 	{ .opve_op = &vnop_mmap_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },       /* mmap */
744 	{ .opve_op = &vnop_fsync_desc, .opve_impl = (VOPFUNC)fdesc_nullop },     /* fsync */
745 	{ .opve_op = &vnop_remove_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },   /* remove */
746 	{ .opve_op = &vnop_link_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },       /* link */
747 	{ .opve_op = &vnop_rename_desc, .opve_impl =  (VOPFUNC)fdesc_notsupp },   /* rename */
748 	{ .opve_op = &vnop_mkdir_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },     /* mkdir */
749 	{ .opve_op = &vnop_rmdir_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },     /* rmdir */
750 	{ .opve_op = &vnop_symlink_desc, .opve_impl = (VOPFUNC)fdesc_notsupp }, /* symlink */
751 	{ .opve_op = &vnop_readdir_desc, .opve_impl = (VOPFUNC)fdesc_error},/* readdir */
752 	{ .opve_op = &vnop_readlink_desc, .opve_impl = (VOPFUNC)err_readlink}, /* readlink */
753 	{ .opve_op = &vnop_inactive_desc, .opve_impl = (VOPFUNC)fdesc_inactive },/* inactive */
754 	{ .opve_op = &vnop_reclaim_desc, .opve_impl = (VOPFUNC)fdesc_reclaim }, /* reclaim */
755 	{ .opve_op = &vnop_strategy_desc, .opve_impl = (VOPFUNC)fdesc_strategy },       /* strategy */
756 	{ .opve_op = &vnop_pathconf_desc, .opve_impl = (VOPFUNC)fdesc_pathconf },       /* pathconf */
757 	{ .opve_op = &vnop_advlock_desc, .opve_impl = (VOPFUNC)fdesc_notsupp }, /* advlock */
758 	{ .opve_op = &vnop_bwrite_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },   /* bwrite */
759 	{ .opve_op = &vnop_pagein_desc, .opve_impl = (VOPFUNC)err_pagein },     /* pagein */
760 	{ .opve_op = &vnop_pageout_desc, .opve_impl = (VOPFUNC)err_pageout },   /* pageout */
761 	{ .opve_op = &vnop_copyfile_desc, .opve_impl = (VOPFUNC)err_copyfile }, /* Copyfile */
762 	{ .opve_op = &vnop_blktooff_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },       /* blktooff */
763 	{ .opve_op = &vnop_blktooff_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },       /* offtoblk */
764 	{ .opve_op = &vnop_blockmap_desc, .opve_impl = (VOPFUNC)fdesc_notsupp },       /* blockmap */
765 	{ .opve_op = (struct vnodeop_desc*)NULL, .opve_impl = (VOPFUNC)NULL }
766 };
767 
768 const struct vnodeopv_desc devfs_fdesc_vnodeop_opv_desc =
769 { .opv_desc_vector_p = &fdesc_vnodeop_p, .opv_desc_ops = devfs_fdesc_vnodeop_entries };
770