1/* $NetBSD: fdesc_vnops.c,v 1.127 2016/08/20 12:37:08 hannken 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. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)fdesc_vnops.c 8.17 (Berkeley) 5/22/95
35 *
36 * #Id: fdesc_vnops.c,v 1.12 1993/04/06 16:17:17 jsp Exp #
37 */
38
39/*
40 * /dev/fd Filesystem
41 */
42
43#include <sys/cdefs.h>
44__KERNEL_RCSID(0, "$NetBSD: fdesc_vnops.c,v 1.127 2016/08/20 12:37:08 hannken Exp $");
45
46#include <sys/param.h>
47#include <sys/systm.h>
48#include <sys/time.h>
49#include <sys/proc.h>
50#include <sys/kernel.h> /* boottime */
51#include <sys/resourcevar.h>
52#include <sys/socketvar.h>
53#include <sys/filedesc.h>
54#include <sys/vnode.h>
55#include <sys/malloc.h>
56#include <sys/conf.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 <sys/tty.h>
64#include <sys/kauth.h>
65#include <sys/atomic.h>
66
67#include <miscfs/fdesc/fdesc.h>
68#include <miscfs/genfs/genfs.h>
69
70#define cttyvp(p) ((p)->p_lflag & PL_CONTROLT ? (p)->p_session->s_ttyvp : NULL)
71
72dev_t devctty;
73
74#if (FD_STDIN != FD_STDOUT-1) || (FD_STDOUT != FD_STDERR-1)
75FD_STDIN, FD_STDOUT, FD_STDERR must be a sequence n, n+1, n+2
76#endif
77
78int fdesc_lookup(void *);
79#define fdesc_create genfs_eopnotsupp
80#define fdesc_mknod genfs_eopnotsupp
81int fdesc_open(void *);
82#define fdesc_close genfs_nullop
83#define fdesc_access genfs_nullop
84int fdesc_getattr(void *);
85int fdesc_setattr(void *);
86int fdesc_read(void *);
87int fdesc_write(void *);
88int fdesc_ioctl(void *);
89int fdesc_poll(void *);
90int fdesc_kqfilter(void *);
91#define fdesc_mmap genfs_eopnotsupp
92#define fdesc_fcntl genfs_fcntl
93#define fdesc_fsync genfs_nullop
94#define fdesc_seek genfs_seek
95#define fdesc_remove genfs_eopnotsupp
96int fdesc_link(void *);
97#define fdesc_rename genfs_eopnotsupp
98#define fdesc_mkdir genfs_eopnotsupp
99#define fdesc_rmdir genfs_eopnotsupp
100int fdesc_symlink(void *);
101int fdesc_readdir(void *);
102int fdesc_readlink(void *);
103#define fdesc_abortop genfs_abortop
104int fdesc_inactive(void *);
105int fdesc_reclaim(void *);
106#define fdesc_lock genfs_lock
107#define fdesc_unlock genfs_unlock
108#define fdesc_bmap genfs_badop
109#define fdesc_strategy genfs_badop
110int fdesc_print(void *);
111int fdesc_pathconf(void *);
112#define fdesc_islocked genfs_islocked
113#define fdesc_advlock genfs_einval
114#define fdesc_bwrite genfs_eopnotsupp
115#define fdesc_revoke genfs_revoke
116#define fdesc_putpages genfs_null_putpages
117
118static int fdesc_attr(int, struct vattr *, kauth_cred_t);
119
120int (**fdesc_vnodeop_p)(void *);
121const struct vnodeopv_entry_desc fdesc_vnodeop_entries[] = {
122 { &vop_default_desc, vn_default_error },
123 { &vop_lookup_desc, fdesc_lookup }, /* lookup */
124 { &vop_create_desc, fdesc_create }, /* create */
125 { &vop_mknod_desc, fdesc_mknod }, /* mknod */
126 { &vop_open_desc, fdesc_open }, /* open */
127 { &vop_close_desc, fdesc_close }, /* close */
128 { &vop_access_desc, fdesc_access }, /* access */
129 { &vop_getattr_desc, fdesc_getattr }, /* getattr */
130 { &vop_setattr_desc, fdesc_setattr }, /* setattr */
131 { &vop_read_desc, fdesc_read }, /* read */
132 { &vop_write_desc, fdesc_write }, /* write */
133 { &vop_fallocate_desc, genfs_eopnotsupp }, /* fallocate */
134 { &vop_fdiscard_desc, genfs_eopnotsupp }, /* fdiscard */
135 { &vop_ioctl_desc, fdesc_ioctl }, /* ioctl */
136 { &vop_fcntl_desc, fdesc_fcntl }, /* fcntl */
137 { &vop_poll_desc, fdesc_poll }, /* poll */
138 { &vop_kqfilter_desc, fdesc_kqfilter }, /* kqfilter */
139 { &vop_revoke_desc, fdesc_revoke }, /* revoke */
140 { &vop_mmap_desc, fdesc_mmap }, /* mmap */
141 { &vop_fsync_desc, fdesc_fsync }, /* fsync */
142 { &vop_seek_desc, fdesc_seek }, /* seek */
143 { &vop_remove_desc, fdesc_remove }, /* remove */
144 { &vop_link_desc, fdesc_link }, /* link */
145 { &vop_rename_desc, fdesc_rename }, /* rename */
146 { &vop_mkdir_desc, fdesc_mkdir }, /* mkdir */
147 { &vop_rmdir_desc, fdesc_rmdir }, /* rmdir */
148 { &vop_symlink_desc, fdesc_symlink }, /* symlink */
149 { &vop_readdir_desc, fdesc_readdir }, /* readdir */
150 { &vop_readlink_desc, fdesc_readlink }, /* readlink */
151 { &vop_abortop_desc, fdesc_abortop }, /* abortop */
152 { &vop_inactive_desc, fdesc_inactive }, /* inactive */
153 { &vop_reclaim_desc, fdesc_reclaim }, /* reclaim */
154 { &vop_lock_desc, fdesc_lock }, /* lock */
155 { &vop_unlock_desc, fdesc_unlock }, /* unlock */
156 { &vop_bmap_desc, fdesc_bmap }, /* bmap */
157 { &vop_strategy_desc, fdesc_strategy }, /* strategy */
158 { &vop_print_desc, fdesc_print }, /* print */
159 { &vop_islocked_desc, fdesc_islocked }, /* islocked */
160 { &vop_pathconf_desc, fdesc_pathconf }, /* pathconf */
161 { &vop_advlock_desc, fdesc_advlock }, /* advlock */
162 { &vop_bwrite_desc, fdesc_bwrite }, /* bwrite */
163 { &vop_putpages_desc, fdesc_putpages }, /* putpages */
164 { NULL, NULL }
165};
166
167const struct vnodeopv_desc fdesc_vnodeop_opv_desc =
168 { &fdesc_vnodeop_p, fdesc_vnodeop_entries };
169
170/*
171 * Initialise cache headers
172 */
173void
174fdesc_init(void)
175{
176 int cttymajor;
177
178 /* locate the major number */
179 cttymajor = devsw_name2chr("ctty", NULL, 0);
180 devctty = makedev(cttymajor, 0);
181}
182
183void
184fdesc_done(void)
185{
186}
187
188/*
189 * vp is the current namei directory
190 * ndp is the name to locate in that directory...
191 */
192int
193fdesc_lookup(void *v)
194{
195 struct vop_lookup_v2_args /* {
196 struct vnode * a_dvp;
197 struct vnode ** a_vpp;
198 struct componentname * a_cnp;
199 } */ *ap = v;
200 struct vnode **vpp = ap->a_vpp;
201 struct vnode *dvp = ap->a_dvp;
202 struct componentname *cnp = ap->a_cnp;
203 struct lwp *l = curlwp;
204 const char *pname = cnp->cn_nameptr;
205 struct proc *p = l->l_proc;
206 unsigned fd = 0;
207 int error, ix = -1;
208 fdtab_t *dt;
209
210 dt = curlwp->l_fd->fd_dt;
211
212 if (cnp->cn_namelen == 1 && *pname == '.') {
213 *vpp = dvp;
214 vref(dvp);
215 return (0);
216 }
217
218 switch (VTOFDESC(dvp)->fd_type) {
219 default:
220 case Flink:
221 case Fdesc:
222 case Fctty:
223 error = ENOTDIR;
224 goto bad;
225
226 case Froot:
227 if (cnp->cn_namelen == 2 && memcmp(pname, "fd", 2) == 0) {
228 ix = FD_DEVFD;
229 goto good;
230 }
231
232 if (cnp->cn_namelen == 3 && memcmp(pname, "tty", 3) == 0) {
233 struct vnode *ttyvp = cttyvp(p);
234 if (ttyvp == NULL) {
235 error = ENXIO;
236 goto bad;
237 }
238 ix = FD_CTTY;
239 goto good;
240 }
241
242 switch (cnp->cn_namelen) {
243 case 5:
244 if (memcmp(pname, "stdin", 5) == 0) {
245 ix = FD_STDIN;
246 goto good;
247 }
248 break;
249 case 6:
250 if (memcmp(pname, "stdout", 6) == 0) {
251 ix = FD_STDOUT;
252 goto good;
253 } else if (memcmp(pname, "stderr", 6) == 0) {
254 ix = FD_STDERR;
255 goto good;
256 }
257 break;
258 }
259
260 error = ENOENT;
261 goto bad;
262
263 case Fdevfd:
264 if (cnp->cn_namelen == 2 && memcmp(pname, "..", 2) == 0) {
265 ix = FD_ROOT;
266 goto good;
267 }
268
269 fd = 0;
270 while (*pname >= '0' && *pname <= '9') {
271 fd = 10 * fd + *pname++ - '0';
272 if (fd >= dt->dt_nfiles)
273 break;
274 }
275
276 if (*pname != '\0') {
277 error = ENOENT;
278 goto bad;
279 }
280
281 if (fd >= dt->dt_nfiles || dt->dt_ff[fd] == NULL ||
282 dt->dt_ff[fd]->ff_file == NULL) {
283 error = EBADF;
284 goto bad;
285 }
286
287 ix = FD_DESC + fd;
288 goto good;
289 }
290
291bad:
292 *vpp = NULL;
293 return error;
294
295good:
296 KASSERT(ix != -1);
297 error = vcache_get(dvp->v_mount, &ix, sizeof(ix), vpp);
298 if (error == 0 && ix == FD_CTTY)
299 (*vpp)->v_type = VCHR;
300 return error;
301}
302
303int
304fdesc_open(void *v)
305{
306 struct vop_open_args /* {
307 struct vnode *a_vp;
308 int a_mode;
309 kauth_cred_t a_cred;
310 } */ *ap = v;
311 struct vnode *vp = ap->a_vp;
312
313 switch (VTOFDESC(vp)->fd_type) {
314 case Fdesc:
315 /*
316 * XXX Kludge: set dupfd to contain the value of the
317 * the file descriptor being sought for duplication. The error
318 * return ensures that the vnode for this device will be
319 * released by vn_open. Open will detect this special error and
320 * take the actions in dupfdopen. Other callers of vn_open or
321 * VOP_OPEN will simply report the error.
322 */
323 curlwp->l_dupfd = VTOFDESC(vp)->fd_fd; /* XXX */
324 return EDUPFD;
325
326 case Fctty:
327 return cdev_open(devctty, ap->a_mode, 0, curlwp);
328 case Froot:
329 case Fdevfd:
330 case Flink:
331 break;
332 }
333
334 return (0);
335}
336
337static int
338fdesc_attr(int fd, struct vattr *vap, kauth_cred_t cred)
339{
340 file_t *fp;
341 struct stat stb;
342 int error;
343
344 if ((fp = fd_getfile(fd)) == NULL)
345 return (EBADF);
346
347 switch (fp->f_type) {
348 case DTYPE_VNODE:
349 vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
350 error = VOP_GETATTR(fp->f_vnode, vap, cred);
351 VOP_UNLOCK(fp->f_vnode);
352 if (error == 0 && vap->va_type == VDIR) {
353 /*
354 * directories can cause loops in the namespace,
355 * so turn off the 'x' bits to avoid trouble.
356 */
357 vap->va_mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH);
358 }
359 break;
360
361 default:
362 memset(&stb, 0, sizeof(stb));
363 error = (*fp->f_ops->fo_stat)(fp, &stb);
364 if (error)
365 break;
366
367 vattr_null(vap);
368 switch(fp->f_type) {
369 case DTYPE_SOCKET:
370 vap->va_type = VSOCK;
371 break;
372 case DTYPE_PIPE:
373 vap->va_type = VFIFO;
374 break;
375 default:
376 /* use VNON perhaps? */
377 vap->va_type = VBAD;
378 break;
379 }
380 vap->va_mode = stb.st_mode;
381 vap->va_nlink = stb.st_nlink;
382 vap->va_uid = stb.st_uid;
383 vap->va_gid = stb.st_gid;
384 vap->va_fsid = stb.st_dev;
385 vap->va_fileid = stb.st_ino;
386 vap->va_size = stb.st_size;
387 vap->va_blocksize = stb.st_blksize;
388 vap->va_atime = stb.st_atimespec;
389 vap->va_mtime = stb.st_mtimespec;
390 vap->va_ctime = stb.st_ctimespec;
391 vap->va_gen = stb.st_gen;
392 vap->va_flags = stb.st_flags;
393 vap->va_rdev = stb.st_rdev;
394 vap->va_bytes = stb.st_blocks * stb.st_blksize;
395 break;
396 }
397
398 fd_putfile(fd);
399 return (error);
400}
401
402int
403fdesc_getattr(void *v)
404{
405 struct vop_getattr_args /* {
406 struct vnode *a_vp;
407 struct vattr *a_vap;
408 kauth_cred_t a_cred;
409 struct lwp *a_l;
410 } */ *ap = v;
411 struct vnode *vp = ap->a_vp;
412 struct vattr *vap = ap->a_vap;
413 unsigned fd;
414 int error = 0;
415
416 switch (VTOFDESC(vp)->fd_type) {
417 case Froot:
418 case Fdevfd:
419 case Flink:
420 case Fctty:
421 vattr_null(vap);
422 vap->va_fileid = VTOFDESC(vp)->fd_ix;
423
424#define R_ALL (S_IRUSR|S_IRGRP|S_IROTH)
425#define W_ALL (S_IWUSR|S_IWGRP|S_IWOTH)
426#define X_ALL (S_IXUSR|S_IXGRP|S_IXOTH)
427
428 switch (VTOFDESC(vp)->fd_type) {
429 case Flink:
430 vap->va_mode = R_ALL|X_ALL;
431 vap->va_type = VLNK;
432 vap->va_rdev = 0;
433 vap->va_nlink = 1;
434 vap->va_size = strlen(VTOFDESC(vp)->fd_link);
435 break;
436
437 case Fctty:
438 vap->va_mode = R_ALL|W_ALL;
439 vap->va_type = VCHR;
440 vap->va_rdev = devctty;
441 vap->va_nlink = 1;
442 vap->va_size = 0;
443 break;
444
445 default:
446 vap->va_mode = R_ALL|X_ALL;
447 vap->va_type = VDIR;
448 vap->va_rdev = 0;
449 vap->va_nlink = 2;
450 vap->va_size = DEV_BSIZE;
451 break;
452 }
453 vap->va_uid = 0;
454 vap->va_gid = 0;
455 vap->va_fsid = vp->v_mount->mnt_stat.f_fsidx.__fsid_val[0];
456 vap->va_blocksize = DEV_BSIZE;
457 vap->va_atime.tv_sec = boottime.tv_sec;
458 vap->va_atime.tv_nsec = 0;
459 vap->va_mtime = vap->va_atime;
460 vap->va_ctime = vap->va_mtime;
461 vap->va_gen = 0;
462 vap->va_flags = 0;
463 vap->va_bytes = 0;
464 break;
465
466 case Fdesc:
467 fd = VTOFDESC(vp)->fd_fd;
468 error = fdesc_attr(fd, vap, ap->a_cred);
469 break;
470
471 default:
472 panic("fdesc_getattr");
473 break;
474 }
475
476 if (error == 0)
477 vp->v_type = vap->va_type;
478
479 return (error);
480}
481
482int
483fdesc_setattr(void *v)
484{
485 struct vop_setattr_args /* {
486 struct vnode *a_vp;
487 struct vattr *a_vap;
488 kauth_cred_t a_cred;
489 } */ *ap = v;
490 file_t *fp;
491 unsigned fd;
492
493 /*
494 * Can't mess with the root vnode
495 */
496 switch (VTOFDESC(ap->a_vp)->fd_type) {
497 case Fdesc:
498 break;
499
500 case Fctty:
501 return (0);
502
503 default:
504 return (EACCES);
505 }
506
507 fd = VTOFDESC(ap->a_vp)->fd_fd;
508 if ((fp = fd_getfile(fd)) == NULL)
509 return (EBADF);
510
511 /*
512 * XXX: Can't reasonably set the attr's on any types currently.
513 * On vnode's this will cause truncation and socket/pipes make
514 * no sense.
515 */
516 fd_putfile(fd);
517 return (0);
518}
519
520
521struct fdesc_target {
522 ino_t ft_fileno;
523 u_char ft_type;
524 u_char ft_namlen;
525 const char *ft_name;
526} fdesc_targets[] = {
527#define N(s) sizeof(s)-1, s
528 { FD_DEVFD, DT_DIR, N("fd") },
529 { FD_STDIN, DT_LNK, N("stdin") },
530 { FD_STDOUT, DT_LNK, N("stdout") },
531 { FD_STDERR, DT_LNK, N("stderr") },
532 { FD_CTTY, DT_UNKNOWN, N("tty") },
533#undef N
534#define UIO_MX _DIRENT_RECLEN((struct dirent *)NULL, sizeof("stderr") - 1)
535};
536static int nfdesc_targets = sizeof(fdesc_targets) / sizeof(fdesc_targets[0]);
537
538int
539fdesc_readdir(void *v)
540{
541 struct vop_readdir_args /* {
542 struct vnode *a_vp;
543 struct uio *a_uio;
544 kauth_cred_t a_cred;
545 int *a_eofflag;
546 off_t **a_cookies;
547 int *a_ncookies;
548 } */ *ap = v;
549 struct uio *uio = ap->a_uio;
550 struct dirent d;
551 off_t i;
552 int j;
553 int error;
554 off_t *cookies = NULL;
555 int ncookies;
556 fdtab_t *dt;
557
558 switch (VTOFDESC(ap->a_vp)->fd_type) {
559 case Fctty:
560 return 0;
561
562 case Fdesc:
563 return ENOTDIR;
564
565 default:
566 break;
567 }
568
569 dt = curlwp->l_fd->fd_dt;
570
571 if (uio->uio_resid < UIO_MX)
572 return EINVAL;
573 if (uio->uio_offset < 0)
574 return EINVAL;
575
576 error = 0;
577 i = uio->uio_offset;
578 (void)memset(&d, 0, UIO_MX);
579 d.d_reclen = UIO_MX;
580 if (ap->a_ncookies)
581 ncookies = uio->uio_resid / UIO_MX;
582 else
583 ncookies = 0;
584
585 if (VTOFDESC(ap->a_vp)->fd_type == Froot) {
586 struct fdesc_target *ft;
587
588 if (i >= nfdesc_targets)
589 return 0;
590
591 if (ap->a_ncookies) {
592 ncookies = min(ncookies, (nfdesc_targets - i));
593 cookies = malloc(ncookies * sizeof(off_t),
594 M_TEMP, M_WAITOK);
595 *ap->a_cookies = cookies;
596 *ap->a_ncookies = ncookies;
597 }
598
599 for (ft = &fdesc_targets[i]; uio->uio_resid >= UIO_MX &&
600 i < nfdesc_targets; ft++, i++) {
601 switch (ft->ft_fileno) {
602 case FD_CTTY:
603 if (cttyvp(curproc) == NULL)
604 continue;
605 break;
606
607 case FD_STDIN:
608 case FD_STDOUT:
609 case FD_STDERR:
610 if ((ft->ft_fileno - FD_STDIN) >=
611 dt->dt_nfiles)
612 continue;
613 if (dt->dt_ff[ft->ft_fileno - FD_STDIN]
614 == NULL || dt->dt_ff[ft->ft_fileno -
615 FD_STDIN]->ff_file == NULL)
616 continue;
617 break;
618 }
619
620 d.d_fileno = ft->ft_fileno;
621 d.d_namlen = ft->ft_namlen;
622 (void)memcpy(d.d_name, ft->ft_name, ft->ft_namlen + 1);
623 d.d_type = ft->ft_type;
624
625 if ((error = uiomove(&d, UIO_MX, uio)) != 0)
626 break;
627 if (cookies)
628 *cookies++ = i + 1;
629 }
630 } else {
631 membar_consumer();
632 if (ap->a_ncookies) {
633 ncookies = min(ncookies, dt->dt_nfiles + 2);
634 cookies = malloc(ncookies * sizeof(off_t),
635 M_TEMP, M_WAITOK);
636 *ap->a_cookies = cookies;
637 *ap->a_ncookies = ncookies;
638 }
639 for (; i - 2 < dt->dt_nfiles && uio->uio_resid >= UIO_MX; i++) {
640 switch (i) {
641 case 0:
642 case 1:
643 d.d_fileno = FD_ROOT; /* XXX */
644 d.d_namlen = i + 1;
645 (void)memcpy(d.d_name, "..", d.d_namlen);
646 d.d_name[i + 1] = '\0';
647 d.d_type = DT_DIR;
648 break;
649
650 default:
651 j = (int)i - 2;
652 if (dt->dt_ff[j] == NULL ||
653 dt->dt_ff[j]->ff_file == NULL)
654 continue;
655 d.d_fileno = j + FD_STDIN;
656 d.d_namlen = snprintf(d.d_name,
657 sizeof(d.d_name), "%d", j);
658 d.d_type = DT_UNKNOWN;
659 break;
660 }
661
662 if ((error = uiomove(&d, UIO_MX, uio)) != 0)
663 break;
664 if (cookies)
665 *cookies++ = i + 1;
666 }
667 }
668
669 if (ap->a_ncookies && error) {
670 free(*ap->a_cookies, M_TEMP);
671 *ap->a_ncookies = 0;
672 *ap->a_cookies = NULL;
673 }
674
675 uio->uio_offset = i;
676 return error;
677}
678
679int
680fdesc_readlink(void *v)
681{
682 struct vop_readlink_args /* {
683 struct vnode *a_vp;
684 struct uio *a_uio;
685 kauth_cred_t a_cred;
686 } */ *ap = v;
687 struct vnode *vp = ap->a_vp;
688 int error;
689
690 if (vp->v_type != VLNK)
691 return (EPERM);
692
693 if (VTOFDESC(vp)->fd_type == Flink) {
694 const char *ln = VTOFDESC(vp)->fd_link;
695 error = uiomove(__UNCONST(ln), strlen(ln), ap->a_uio);
696 } else {
697 error = EOPNOTSUPP;
698 }
699
700 return (error);
701}
702
703int
704fdesc_read(void *v)
705{
706 struct vop_read_args /* {
707 struct vnode *a_vp;
708 struct uio *a_uio;
709 int a_ioflag;
710 kauth_cred_t a_cred;
711 } */ *ap = v;
712 int error = EOPNOTSUPP;
713 struct vnode *vp = ap->a_vp;
714
715 switch (VTOFDESC(vp)->fd_type) {
716 case Fctty:
717 VOP_UNLOCK(vp);
718 error = cdev_read(devctty, ap->a_uio, ap->a_ioflag);
719 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
720 break;
721
722 default:
723 error = EOPNOTSUPP;
724 break;
725 }
726
727 return (error);
728}
729
730int
731fdesc_write(void *v)
732{
733 struct vop_write_args /* {
734 struct vnode *a_vp;
735 struct uio *a_uio;
736 int a_ioflag;
737 kauth_cred_t a_cred;
738 } */ *ap = v;
739 int error = EOPNOTSUPP;
740 struct vnode *vp = ap->a_vp;
741
742 switch (VTOFDESC(vp)->fd_type) {
743 case Fctty:
744 VOP_UNLOCK(vp);
745 error = cdev_write(devctty, ap->a_uio, ap->a_ioflag);
746 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
747 break;
748
749 default:
750 error = EOPNOTSUPP;
751 break;
752 }
753
754 return (error);
755}
756
757int
758fdesc_ioctl(void *v)
759{
760 struct vop_ioctl_args /* {
761 struct vnode *a_vp;
762 u_long a_command;
763 void *a_data;
764 int a_fflag;
765 kauth_cred_t a_cred;
766 } */ *ap = v;
767 int error = EOPNOTSUPP;
768
769 switch (VTOFDESC(ap->a_vp)->fd_type) {
770 case Fctty:
771 error = cdev_ioctl(devctty, ap->a_command, ap->a_data,
772 ap->a_fflag, curlwp);
773 break;
774
775 default:
776 error = EOPNOTSUPP;
777 break;
778 }
779
780 return (error);
781}
782
783int
784fdesc_poll(void *v)
785{
786 struct vop_poll_args /* {
787 struct vnode *a_vp;
788 int a_events;
789 } */ *ap = v;
790 int revents;
791
792 switch (VTOFDESC(ap->a_vp)->fd_type) {
793 case Fctty:
794 revents = cdev_poll(devctty, ap->a_events, curlwp);
795 break;
796
797 default:
798 revents = genfs_poll(v);
799 break;
800 }
801
802 return (revents);
803}
804
805int
806fdesc_kqfilter(void *v)
807{
808 struct vop_kqfilter_args /* {
809 struct vnode *a_vp;
810 struct knote *a_kn;
811 } */ *ap = v;
812 int error, fd;
813 file_t *fp;
814
815 switch (VTOFDESC(ap->a_vp)->fd_type) {
816 case Fctty:
817 error = cdev_kqfilter(devctty, ap->a_kn);
818 break;
819
820 case Fdesc:
821 /* just invoke kqfilter for the underlying descriptor */
822 fd = VTOFDESC(ap->a_vp)->fd_fd;
823 if ((fp = fd_getfile(fd)) == NULL)
824 return (1);
825 error = (*fp->f_ops->fo_kqfilter)(fp, ap->a_kn);
826 fd_putfile(fd);
827 break;
828
829 default:
830 return (genfs_kqfilter(v));
831 }
832
833 return (error);
834}
835
836int
837fdesc_inactive(void *v)
838{
839 struct vop_inactive_args /* {
840 struct vnode *a_vp;
841 } */ *ap = v;
842 struct vnode *vp = ap->a_vp;
843 struct fdescnode *fd = VTOFDESC(vp);
844
845 /*
846 * Clear out the v_type field to avoid
847 * nasty things happening on reclaim.
848 */
849 if (fd->fd_type == Fctty || fd->fd_type == Fdesc)
850 vp->v_type = VNON;
851 VOP_UNLOCK(vp);
852 return (0);
853}
854
855int
856fdesc_reclaim(void *v)
857{
858 struct vop_reclaim_args /* {
859 struct vnode *a_vp;
860 } */ *ap = v;
861 struct vnode *vp = ap->a_vp;
862 struct fdescnode *fd = VTOFDESC(vp);
863
864 vp->v_data = NULL;
865 kmem_free(fd, sizeof(struct fdescnode));
866
867 return (0);
868}
869
870/*
871 * Return POSIX pathconf information applicable to special devices.
872 */
873int
874fdesc_pathconf(void *v)
875{
876 struct vop_pathconf_args /* {
877 struct vnode *a_vp;
878 int a_name;
879 register_t *a_retval;
880 } */ *ap = v;
881
882 switch (ap->a_name) {
883 case _PC_LINK_MAX:
884 *ap->a_retval = LINK_MAX;
885 return (0);
886 case _PC_MAX_CANON:
887 *ap->a_retval = MAX_CANON;
888 return (0);
889 case _PC_MAX_INPUT:
890 *ap->a_retval = MAX_INPUT;
891 return (0);
892 case _PC_PIPE_BUF:
893 *ap->a_retval = PIPE_BUF;
894 return (0);
895 case _PC_CHOWN_RESTRICTED:
896 *ap->a_retval = 1;
897 return (0);
898 case _PC_VDISABLE:
899 *ap->a_retval = _POSIX_VDISABLE;
900 return (0);
901 case _PC_SYNC_IO:
902 *ap->a_retval = 1;
903 return (0);
904 default:
905 return (EINVAL);
906 }
907 /* NOTREACHED */
908}
909
910/*
911 * Print out the contents of a /dev/fd vnode.
912 */
913/* ARGSUSED */
914int
915fdesc_print(void *v)
916{
917 printf("tag VT_NON, fdesc vnode\n");
918 return (0);
919}
920
921int
922fdesc_link(void *v)
923{
924 struct vop_link_v2_args /* {
925 struct vnode *a_dvp;
926 struct vnode *a_vp;
927 struct componentname *a_cnp;
928 } */ *ap = v;
929
930 VOP_ABORTOP(ap->a_dvp, ap->a_cnp);
931 return (EROFS);
932}
933
934int
935fdesc_symlink(void *v)
936{
937 struct vop_symlink_v3_args /* {
938 struct vnode *a_dvp;
939 struct vnode **a_vpp;
940 struct componentname *a_cnp;
941 struct vattr *a_vap;
942 char *a_target;
943 } */ *ap = v;
944
945 VOP_ABORTOP(ap->a_dvp, ap->a_cnp);
946 return (EROFS);
947}
948