fdesc_vnops.c revision 1.109.4.3 1 /* $NetBSD: fdesc_vnops.c,v 1.109.4.3 2011/05/19 03:43:03 rmind 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 1.109.4.3 2011/05/19 03:43:03 rmind 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
72 static kmutex_t fdcache_lock;
73
74 dev_t devctty;
75
76 #if (FD_STDIN != FD_STDOUT-1) || (FD_STDOUT != FD_STDERR-1)
77 FD_STDIN, FD_STDOUT, FD_STDERR must be a sequence n, n+1, n+2
78 #endif
79
80 #define NFDCACHE 4
81
82 #define FD_NHASH(ix) \
83 (&fdhashtbl[(ix) & fdhash])
84 LIST_HEAD(fdhashhead, fdescnode) *fdhashtbl;
85 u_long fdhash;
86
87 int fdesc_lookup(void *);
88 #define fdesc_create genfs_eopnotsupp
89 #define fdesc_mknod genfs_eopnotsupp
90 int fdesc_open(void *);
91 #define fdesc_close genfs_nullop
92 #define fdesc_access genfs_nullop
93 int fdesc_getattr(void *);
94 int fdesc_setattr(void *);
95 int fdesc_read(void *);
96 int fdesc_write(void *);
97 int fdesc_ioctl(void *);
98 int fdesc_poll(void *);
99 int fdesc_kqfilter(void *);
100 #define fdesc_mmap genfs_eopnotsupp
101 #define fdesc_fcntl genfs_fcntl
102 #define fdesc_fsync genfs_nullop
103 #define fdesc_seek genfs_seek
104 #define fdesc_remove genfs_eopnotsupp
105 int fdesc_link(void *);
106 #define fdesc_rename genfs_eopnotsupp
107 #define fdesc_mkdir genfs_eopnotsupp
108 #define fdesc_rmdir genfs_eopnotsupp
109 int fdesc_symlink(void *);
110 int fdesc_readdir(void *);
111 int fdesc_readlink(void *);
112 #define fdesc_abortop genfs_abortop
113 int fdesc_inactive(void *);
114 int fdesc_reclaim(void *);
115 #define fdesc_lock genfs_lock
116 #define fdesc_unlock genfs_unlock
117 #define fdesc_bmap genfs_badop
118 #define fdesc_strategy genfs_badop
119 int fdesc_print(void *);
120 int fdesc_pathconf(void *);
121 #define fdesc_islocked genfs_islocked
122 #define fdesc_advlock genfs_einval
123 #define fdesc_bwrite genfs_eopnotsupp
124 #define fdesc_revoke genfs_revoke
125 #define fdesc_putpages genfs_null_putpages
126
127 static int fdesc_attr(int, struct vattr *, kauth_cred_t);
128
129 int (**fdesc_vnodeop_p)(void *);
130 const struct vnodeopv_entry_desc fdesc_vnodeop_entries[] = {
131 { &vop_default_desc, vn_default_error },
132 { &vop_lookup_desc, fdesc_lookup }, /* lookup */
133 { &vop_create_desc, fdesc_create }, /* create */
134 { &vop_mknod_desc, fdesc_mknod }, /* mknod */
135 { &vop_open_desc, fdesc_open }, /* open */
136 { &vop_close_desc, fdesc_close }, /* close */
137 { &vop_access_desc, fdesc_access }, /* access */
138 { &vop_getattr_desc, fdesc_getattr }, /* getattr */
139 { &vop_setattr_desc, fdesc_setattr }, /* setattr */
140 { &vop_read_desc, fdesc_read }, /* read */
141 { &vop_write_desc, fdesc_write }, /* write */
142 { &vop_ioctl_desc, fdesc_ioctl }, /* ioctl */
143 { &vop_fcntl_desc, fdesc_fcntl }, /* fcntl */
144 { &vop_poll_desc, fdesc_poll }, /* poll */
145 { &vop_kqfilter_desc, fdesc_kqfilter }, /* kqfilter */
146 { &vop_revoke_desc, fdesc_revoke }, /* revoke */
147 { &vop_mmap_desc, fdesc_mmap }, /* mmap */
148 { &vop_fsync_desc, fdesc_fsync }, /* fsync */
149 { &vop_seek_desc, fdesc_seek }, /* seek */
150 { &vop_remove_desc, fdesc_remove }, /* remove */
151 { &vop_link_desc, fdesc_link }, /* link */
152 { &vop_rename_desc, fdesc_rename }, /* rename */
153 { &vop_mkdir_desc, fdesc_mkdir }, /* mkdir */
154 { &vop_rmdir_desc, fdesc_rmdir }, /* rmdir */
155 { &vop_symlink_desc, fdesc_symlink }, /* symlink */
156 { &vop_readdir_desc, fdesc_readdir }, /* readdir */
157 { &vop_readlink_desc, fdesc_readlink }, /* readlink */
158 { &vop_abortop_desc, fdesc_abortop }, /* abortop */
159 { &vop_inactive_desc, fdesc_inactive }, /* inactive */
160 { &vop_reclaim_desc, fdesc_reclaim }, /* reclaim */
161 { &vop_lock_desc, fdesc_lock }, /* lock */
162 { &vop_unlock_desc, fdesc_unlock }, /* unlock */
163 { &vop_bmap_desc, fdesc_bmap }, /* bmap */
164 { &vop_strategy_desc, fdesc_strategy }, /* strategy */
165 { &vop_print_desc, fdesc_print }, /* print */
166 { &vop_islocked_desc, fdesc_islocked }, /* islocked */
167 { &vop_pathconf_desc, fdesc_pathconf }, /* pathconf */
168 { &vop_advlock_desc, fdesc_advlock }, /* advlock */
169 { &vop_bwrite_desc, fdesc_bwrite }, /* bwrite */
170 { &vop_putpages_desc, fdesc_putpages }, /* putpages */
171 { NULL, NULL }
172 };
173
174 const struct vnodeopv_desc fdesc_vnodeop_opv_desc =
175 { &fdesc_vnodeop_p, fdesc_vnodeop_entries };
176
177 /*
178 * Initialise cache headers
179 */
180 void
181 fdesc_init(void)
182 {
183 int cttymajor;
184
185 /* locate the major number */
186 cttymajor = devsw_name2chr("ctty", NULL, 0);
187 devctty = makedev(cttymajor, 0);
188 mutex_init(&fdcache_lock, MUTEX_DEFAULT, IPL_NONE);
189 fdhashtbl = hashinit(NFDCACHE, HASH_LIST, true, &fdhash);
190 }
191
192 /*
193 * Free hash table.
194 */
195 void
196 fdesc_done(void)
197 {
198 hashdone(fdhashtbl, HASH_LIST, fdhash);
199 mutex_destroy(&fdcache_lock);
200 }
201
202 /*
203 * Return a locked vnode of the correct type.
204 */
205 int
206 fdesc_allocvp(fdntype ftype, int ix, struct mount *mp, struct vnode **vpp)
207 {
208 struct fdhashhead *fc;
209 struct fdescnode *fd;
210 int error = 0;
211
212 fc = FD_NHASH(ix);
213 loop:
214 mutex_enter(&fdcache_lock);
215 LIST_FOREACH(fd, fc, fd_hash) {
216 if (fd->fd_ix == ix && fd->fd_vnode->v_mount == mp) {
217 mutex_enter(fd->fd_vnode->v_interlock);
218 mutex_exit(&fdcache_lock);
219 if (vget(fd->fd_vnode, LK_EXCLUSIVE))
220 goto loop;
221 *vpp = fd->fd_vnode;
222 return 0;
223 }
224 }
225 mutex_exit(&fdcache_lock);
226
227 error = getnewvnode(VT_FDESC, mp, fdesc_vnodeop_p, NULL, vpp);
228 if (error)
229 return error;
230
231 mutex_enter(&fdcache_lock);
232 LIST_FOREACH(fd, fc, fd_hash) {
233 if (fd->fd_ix == ix && fd->fd_vnode->v_mount == mp) {
234 /*
235 * Another thread beat us, push back freshly
236 * allocated vnode and retry.
237 */
238 mutex_exit(&fdcache_lock);
239 ungetnewvnode(*vpp);
240 goto loop;
241 }
242 }
243
244 fd = malloc(sizeof(struct fdescnode), M_TEMP, M_WAITOK);
245 (*vpp)->v_data = fd;
246 fd->fd_vnode = *vpp;
247 fd->fd_type = ftype;
248 fd->fd_fd = -1;
249 fd->fd_link = 0;
250 fd->fd_ix = ix;
251 uvm_vnp_setsize(*vpp, 0);
252 VOP_LOCK(*vpp, LK_EXCLUSIVE);
253 LIST_INSERT_HEAD(fc, fd, fd_hash);
254 mutex_exit(&fdcache_lock);
255
256 return 0;
257 }
258
259 /*
260 * vp is the current namei directory
261 * ndp is the name to locate in that directory...
262 */
263 int
264 fdesc_lookup(void *v)
265 {
266 struct vop_lookup_args /* {
267 struct vnode * a_dvp;
268 struct vnode ** a_vpp;
269 struct componentname * a_cnp;
270 } */ *ap = v;
271 struct vnode **vpp = ap->a_vpp;
272 struct vnode *dvp = ap->a_dvp;
273 struct componentname *cnp = ap->a_cnp;
274 struct lwp *l = curlwp;
275 const char *pname = cnp->cn_nameptr;
276 struct proc *p = l->l_proc;
277 unsigned fd = 0;
278 int error;
279 struct vnode *fvp;
280 const char *ln;
281 fdtab_t *dt;
282
283 dt = curlwp->l_fd->fd_dt;
284
285 if (cnp->cn_namelen == 1 && *pname == '.') {
286 *vpp = dvp;
287 vref(dvp);
288 return (0);
289 }
290
291 switch (VTOFDESC(dvp)->fd_type) {
292 default:
293 case Flink:
294 case Fdesc:
295 case Fctty:
296 error = ENOTDIR;
297 goto bad;
298
299 case Froot:
300 if (cnp->cn_namelen == 2 && memcmp(pname, "fd", 2) == 0) {
301 error = fdesc_allocvp(Fdevfd, FD_DEVFD, dvp->v_mount, &fvp);
302 if (error)
303 goto bad;
304 *vpp = fvp;
305 fvp->v_type = VDIR;
306 goto good;
307 }
308
309 if (cnp->cn_namelen == 3 && memcmp(pname, "tty", 3) == 0) {
310 struct vnode *ttyvp = cttyvp(p);
311 if (ttyvp == NULL) {
312 error = ENXIO;
313 goto bad;
314 }
315 error = fdesc_allocvp(Fctty, FD_CTTY, dvp->v_mount, &fvp);
316 if (error)
317 goto bad;
318 *vpp = fvp;
319 fvp->v_type = VCHR;
320 goto good;
321 }
322
323 ln = 0;
324 switch (cnp->cn_namelen) {
325 case 5:
326 if (memcmp(pname, "stdin", 5) == 0) {
327 ln = "fd/0";
328 fd = FD_STDIN;
329 }
330 break;
331 case 6:
332 if (memcmp(pname, "stdout", 6) == 0) {
333 ln = "fd/1";
334 fd = FD_STDOUT;
335 } else
336 if (memcmp(pname, "stderr", 6) == 0) {
337 ln = "fd/2";
338 fd = FD_STDERR;
339 }
340 break;
341 }
342
343 if (ln) {
344 error = fdesc_allocvp(Flink, fd, dvp->v_mount, &fvp);
345 if (error)
346 goto bad;
347 /* XXXUNCONST */
348 VTOFDESC(fvp)->fd_link = __UNCONST(ln);
349 *vpp = fvp;
350 fvp->v_type = VLNK;
351 goto good;
352 } else {
353 error = ENOENT;
354 goto bad;
355 }
356
357 /* FALL THROUGH */
358
359 case Fdevfd:
360 if (cnp->cn_namelen == 2 && memcmp(pname, "..", 2) == 0) {
361 VOP_UNLOCK(dvp);
362 error = fdesc_root(dvp->v_mount, vpp);
363 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
364 if (error)
365 goto bad;
366 return (error);
367 }
368
369 fd = 0;
370 while (*pname >= '0' && *pname <= '9') {
371 fd = 10 * fd + *pname++ - '0';
372 if (fd >= dt->dt_nfiles)
373 break;
374 }
375
376 if (*pname != '\0') {
377 error = ENOENT;
378 goto bad;
379 }
380
381 if (fd >= dt->dt_nfiles || dt->dt_ff[fd] == NULL ||
382 dt->dt_ff[fd]->ff_file == NULL) {
383 error = EBADF;
384 goto bad;
385 }
386
387 error = fdesc_allocvp(Fdesc, FD_DESC+fd, dvp->v_mount, &fvp);
388 if (error)
389 goto bad;
390 VTOFDESC(fvp)->fd_fd = fd;
391 *vpp = fvp;
392 goto good;
393 }
394
395 bad:
396 *vpp = NULL;
397 return (error);
398
399 good:
400 return (0);
401 }
402
403 int
404 fdesc_open(void *v)
405 {
406 struct vop_open_args /* {
407 struct vnode *a_vp;
408 int a_mode;
409 kauth_cred_t a_cred;
410 } */ *ap = v;
411 struct vnode *vp = ap->a_vp;
412
413 switch (VTOFDESC(vp)->fd_type) {
414 case Fdesc:
415 /*
416 * XXX Kludge: set dupfd to contain the value of the
417 * the file descriptor being sought for duplication. The error
418 * return ensures that the vnode for this device will be
419 * released by vn_open. Open will detect this special error and
420 * take the actions in dupfdopen. Other callers of vn_open or
421 * VOP_OPEN will simply report the error.
422 */
423 curlwp->l_dupfd = VTOFDESC(vp)->fd_fd; /* XXX */
424 return EDUPFD;
425
426 case Fctty:
427 return cdev_open(devctty, ap->a_mode, 0, curlwp);
428 case Froot:
429 case Fdevfd:
430 case Flink:
431 break;
432 }
433
434 return (0);
435 }
436
437 static int
438 fdesc_attr(int fd, struct vattr *vap, kauth_cred_t cred)
439 {
440 file_t *fp;
441 struct stat stb;
442 int error;
443
444 if ((fp = fd_getfile(fd)) == NULL)
445 return (EBADF);
446
447 switch (fp->f_type) {
448 case DTYPE_VNODE:
449 error = VOP_GETATTR((struct vnode *) fp->f_data, vap, cred);
450 if (error == 0 && vap->va_type == VDIR) {
451 /*
452 * directories can cause loops in the namespace,
453 * so turn off the 'x' bits to avoid trouble.
454 */
455 vap->va_mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH);
456 }
457 break;
458
459 default:
460 memset(&stb, 0, sizeof(stb));
461 error = (*fp->f_ops->fo_stat)(fp, &stb);
462 if (error)
463 break;
464
465 vattr_null(vap);
466 switch(fp->f_type) {
467 case DTYPE_SOCKET:
468 vap->va_type = VSOCK;
469 break;
470 case DTYPE_PIPE:
471 vap->va_type = VFIFO;
472 break;
473 default:
474 /* use VNON perhaps? */
475 vap->va_type = VBAD;
476 break;
477 }
478 vap->va_mode = stb.st_mode;
479 vap->va_nlink = stb.st_nlink;
480 vap->va_uid = stb.st_uid;
481 vap->va_gid = stb.st_gid;
482 vap->va_fsid = stb.st_dev;
483 vap->va_fileid = stb.st_ino;
484 vap->va_size = stb.st_size;
485 vap->va_blocksize = stb.st_blksize;
486 vap->va_atime = stb.st_atimespec;
487 vap->va_mtime = stb.st_mtimespec;
488 vap->va_ctime = stb.st_ctimespec;
489 vap->va_gen = stb.st_gen;
490 vap->va_flags = stb.st_flags;
491 vap->va_rdev = stb.st_rdev;
492 vap->va_bytes = stb.st_blocks * stb.st_blksize;
493 break;
494 }
495
496 fd_putfile(fd);
497 return (error);
498 }
499
500 int
501 fdesc_getattr(void *v)
502 {
503 struct vop_getattr_args /* {
504 struct vnode *a_vp;
505 struct vattr *a_vap;
506 kauth_cred_t a_cred;
507 struct lwp *a_l;
508 } */ *ap = v;
509 struct vnode *vp = ap->a_vp;
510 struct vattr *vap = ap->a_vap;
511 unsigned fd;
512 int error = 0;
513
514 switch (VTOFDESC(vp)->fd_type) {
515 case Froot:
516 case Fdevfd:
517 case Flink:
518 case Fctty:
519 vattr_null(vap);
520 vap->va_fileid = VTOFDESC(vp)->fd_ix;
521
522 #define R_ALL (S_IRUSR|S_IRGRP|S_IROTH)
523 #define W_ALL (S_IWUSR|S_IWGRP|S_IWOTH)
524 #define X_ALL (S_IXUSR|S_IXGRP|S_IXOTH)
525
526 switch (VTOFDESC(vp)->fd_type) {
527 case Flink:
528 vap->va_mode = R_ALL|X_ALL;
529 vap->va_type = VLNK;
530 vap->va_rdev = 0;
531 vap->va_nlink = 1;
532 vap->va_size = strlen(VTOFDESC(vp)->fd_link);
533 break;
534
535 case Fctty:
536 vap->va_mode = R_ALL|W_ALL;
537 vap->va_type = VCHR;
538 vap->va_rdev = devctty;
539 vap->va_nlink = 1;
540 vap->va_size = 0;
541 break;
542
543 default:
544 vap->va_mode = R_ALL|X_ALL;
545 vap->va_type = VDIR;
546 vap->va_rdev = 0;
547 vap->va_nlink = 2;
548 vap->va_size = DEV_BSIZE;
549 break;
550 }
551 vap->va_uid = 0;
552 vap->va_gid = 0;
553 vap->va_fsid = vp->v_mount->mnt_stat.f_fsidx.__fsid_val[0];
554 vap->va_blocksize = DEV_BSIZE;
555 vap->va_atime.tv_sec = boottime.tv_sec;
556 vap->va_atime.tv_nsec = 0;
557 vap->va_mtime = vap->va_atime;
558 vap->va_ctime = vap->va_mtime;
559 vap->va_gen = 0;
560 vap->va_flags = 0;
561 vap->va_bytes = 0;
562 break;
563
564 case Fdesc:
565 fd = VTOFDESC(vp)->fd_fd;
566 error = fdesc_attr(fd, vap, ap->a_cred);
567 break;
568
569 default:
570 panic("fdesc_getattr");
571 break;
572 }
573
574 if (error == 0)
575 vp->v_type = vap->va_type;
576
577 return (error);
578 }
579
580 int
581 fdesc_setattr(void *v)
582 {
583 struct vop_setattr_args /* {
584 struct vnode *a_vp;
585 struct vattr *a_vap;
586 kauth_cred_t a_cred;
587 } */ *ap = v;
588 file_t *fp;
589 unsigned fd;
590
591 /*
592 * Can't mess with the root vnode
593 */
594 switch (VTOFDESC(ap->a_vp)->fd_type) {
595 case Fdesc:
596 break;
597
598 case Fctty:
599 return (0);
600
601 default:
602 return (EACCES);
603 }
604
605 fd = VTOFDESC(ap->a_vp)->fd_fd;
606 if ((fp = fd_getfile(fd)) == NULL)
607 return (EBADF);
608
609 /*
610 * XXX: Can't reasonably set the attr's on any types currently.
611 * On vnode's this will cause truncation and socket/pipes make
612 * no sense.
613 */
614 fd_putfile(fd);
615 return (0);
616 }
617
618
619 struct fdesc_target {
620 ino_t ft_fileno;
621 u_char ft_type;
622 u_char ft_namlen;
623 const char *ft_name;
624 } fdesc_targets[] = {
625 #define N(s) sizeof(s)-1, s
626 { FD_DEVFD, DT_DIR, N("fd") },
627 { FD_STDIN, DT_LNK, N("stdin") },
628 { FD_STDOUT, DT_LNK, N("stdout") },
629 { FD_STDERR, DT_LNK, N("stderr") },
630 { FD_CTTY, DT_UNKNOWN, N("tty") },
631 #undef N
632 #define UIO_MX _DIRENT_RECLEN((struct dirent *)NULL, sizeof("stderr") - 1)
633 };
634 static int nfdesc_targets = sizeof(fdesc_targets) / sizeof(fdesc_targets[0]);
635
636 int
637 fdesc_readdir(void *v)
638 {
639 struct vop_readdir_args /* {
640 struct vnode *a_vp;
641 struct uio *a_uio;
642 kauth_cred_t a_cred;
643 int *a_eofflag;
644 off_t **a_cookies;
645 int *a_ncookies;
646 } */ *ap = v;
647 struct uio *uio = ap->a_uio;
648 struct dirent d;
649 off_t i;
650 int j;
651 int error;
652 off_t *cookies = NULL;
653 int ncookies;
654 fdtab_t *dt;
655
656 switch (VTOFDESC(ap->a_vp)->fd_type) {
657 case Fctty:
658 return 0;
659
660 case Fdesc:
661 return ENOTDIR;
662
663 default:
664 break;
665 }
666
667 dt = curlwp->l_fd->fd_dt;
668
669 if (uio->uio_resid < UIO_MX)
670 return EINVAL;
671 if (uio->uio_offset < 0)
672 return EINVAL;
673
674 error = 0;
675 i = uio->uio_offset;
676 (void)memset(&d, 0, UIO_MX);
677 d.d_reclen = UIO_MX;
678 if (ap->a_ncookies)
679 ncookies = uio->uio_resid / UIO_MX;
680 else
681 ncookies = 0;
682
683 if (VTOFDESC(ap->a_vp)->fd_type == Froot) {
684 struct fdesc_target *ft;
685
686 if (i >= nfdesc_targets)
687 return 0;
688
689 if (ap->a_ncookies) {
690 ncookies = min(ncookies, (nfdesc_targets - i));
691 cookies = malloc(ncookies * sizeof(off_t),
692 M_TEMP, M_WAITOK);
693 *ap->a_cookies = cookies;
694 *ap->a_ncookies = ncookies;
695 }
696
697 for (ft = &fdesc_targets[i]; uio->uio_resid >= UIO_MX &&
698 i < nfdesc_targets; ft++, i++) {
699 switch (ft->ft_fileno) {
700 case FD_CTTY:
701 if (cttyvp(curproc) == NULL)
702 continue;
703 break;
704
705 case FD_STDIN:
706 case FD_STDOUT:
707 case FD_STDERR:
708 if ((ft->ft_fileno - FD_STDIN) >=
709 dt->dt_nfiles)
710 continue;
711 if (dt->dt_ff[ft->ft_fileno - FD_STDIN]
712 == NULL || dt->dt_ff[ft->ft_fileno -
713 FD_STDIN]->ff_file == NULL)
714 continue;
715 break;
716 }
717
718 d.d_fileno = ft->ft_fileno;
719 d.d_namlen = ft->ft_namlen;
720 (void)memcpy(d.d_name, ft->ft_name, ft->ft_namlen + 1);
721 d.d_type = ft->ft_type;
722
723 if ((error = uiomove(&d, UIO_MX, uio)) != 0)
724 break;
725 if (cookies)
726 *cookies++ = i + 1;
727 }
728 } else {
729 membar_consumer();
730 if (ap->a_ncookies) {
731 ncookies = min(ncookies, dt->dt_nfiles + 2);
732 cookies = malloc(ncookies * sizeof(off_t),
733 M_TEMP, M_WAITOK);
734 *ap->a_cookies = cookies;
735 *ap->a_ncookies = ncookies;
736 }
737 for (; i - 2 < dt->dt_nfiles && uio->uio_resid >= UIO_MX; i++) {
738 switch (i) {
739 case 0:
740 case 1:
741 d.d_fileno = FD_ROOT; /* XXX */
742 d.d_namlen = i + 1;
743 (void)memcpy(d.d_name, "..", d.d_namlen);
744 d.d_name[i + 1] = '\0';
745 d.d_type = DT_DIR;
746 break;
747
748 default:
749 j = (int)i - 2;
750 if (dt->dt_ff[j] == NULL ||
751 dt->dt_ff[j]->ff_file == NULL)
752 continue;
753 d.d_fileno = j + FD_STDIN;
754 d.d_namlen = sprintf(d.d_name, "%d", j);
755 d.d_type = DT_UNKNOWN;
756 break;
757 }
758
759 if ((error = uiomove(&d, UIO_MX, uio)) != 0)
760 break;
761 if (cookies)
762 *cookies++ = i + 1;
763 }
764 }
765
766 if (ap->a_ncookies && error) {
767 free(*ap->a_cookies, M_TEMP);
768 *ap->a_ncookies = 0;
769 *ap->a_cookies = NULL;
770 }
771
772 uio->uio_offset = i;
773 return error;
774 }
775
776 int
777 fdesc_readlink(void *v)
778 {
779 struct vop_readlink_args /* {
780 struct vnode *a_vp;
781 struct uio *a_uio;
782 kauth_cred_t a_cred;
783 } */ *ap = v;
784 struct vnode *vp = ap->a_vp;
785 int error;
786
787 if (vp->v_type != VLNK)
788 return (EPERM);
789
790 if (VTOFDESC(vp)->fd_type == Flink) {
791 char *ln = VTOFDESC(vp)->fd_link;
792 error = uiomove(ln, strlen(ln), ap->a_uio);
793 } else {
794 error = EOPNOTSUPP;
795 }
796
797 return (error);
798 }
799
800 int
801 fdesc_read(void *v)
802 {
803 struct vop_read_args /* {
804 struct vnode *a_vp;
805 struct uio *a_uio;
806 int a_ioflag;
807 kauth_cred_t a_cred;
808 } */ *ap = v;
809 int error = EOPNOTSUPP;
810 struct vnode *vp = ap->a_vp;
811
812 switch (VTOFDESC(vp)->fd_type) {
813 case Fctty:
814 VOP_UNLOCK(vp);
815 error = cdev_read(devctty, ap->a_uio, ap->a_ioflag);
816 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
817 break;
818
819 default:
820 error = EOPNOTSUPP;
821 break;
822 }
823
824 return (error);
825 }
826
827 int
828 fdesc_write(void *v)
829 {
830 struct vop_write_args /* {
831 struct vnode *a_vp;
832 struct uio *a_uio;
833 int a_ioflag;
834 kauth_cred_t a_cred;
835 } */ *ap = v;
836 int error = EOPNOTSUPP;
837 struct vnode *vp = ap->a_vp;
838
839 switch (VTOFDESC(vp)->fd_type) {
840 case Fctty:
841 VOP_UNLOCK(vp);
842 error = cdev_write(devctty, ap->a_uio, ap->a_ioflag);
843 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
844 break;
845
846 default:
847 error = EOPNOTSUPP;
848 break;
849 }
850
851 return (error);
852 }
853
854 int
855 fdesc_ioctl(void *v)
856 {
857 struct vop_ioctl_args /* {
858 struct vnode *a_vp;
859 u_long a_command;
860 void *a_data;
861 int a_fflag;
862 kauth_cred_t a_cred;
863 } */ *ap = v;
864 int error = EOPNOTSUPP;
865
866 switch (VTOFDESC(ap->a_vp)->fd_type) {
867 case Fctty:
868 error = cdev_ioctl(devctty, ap->a_command, ap->a_data,
869 ap->a_fflag, curlwp);
870 break;
871
872 default:
873 error = EOPNOTSUPP;
874 break;
875 }
876
877 return (error);
878 }
879
880 int
881 fdesc_poll(void *v)
882 {
883 struct vop_poll_args /* {
884 struct vnode *a_vp;
885 int a_events;
886 } */ *ap = v;
887 int revents;
888
889 switch (VTOFDESC(ap->a_vp)->fd_type) {
890 case Fctty:
891 revents = cdev_poll(devctty, ap->a_events, curlwp);
892 break;
893
894 default:
895 revents = genfs_poll(v);
896 break;
897 }
898
899 return (revents);
900 }
901
902 int
903 fdesc_kqfilter(void *v)
904 {
905 struct vop_kqfilter_args /* {
906 struct vnode *a_vp;
907 struct knote *a_kn;
908 } */ *ap = v;
909 int error, fd;
910 file_t *fp;
911
912 switch (VTOFDESC(ap->a_vp)->fd_type) {
913 case Fctty:
914 error = cdev_kqfilter(devctty, ap->a_kn);
915 break;
916
917 case Fdesc:
918 /* just invoke kqfilter for the underlying descriptor */
919 fd = VTOFDESC(ap->a_vp)->fd_fd;
920 if ((fp = fd_getfile(fd)) == NULL)
921 return (1);
922 error = (*fp->f_ops->fo_kqfilter)(fp, ap->a_kn);
923 fd_putfile(fd);
924 break;
925
926 default:
927 return (genfs_kqfilter(v));
928 }
929
930 return (error);
931 }
932
933 int
934 fdesc_inactive(void *v)
935 {
936 struct vop_inactive_args /* {
937 struct vnode *a_vp;
938 } */ *ap = v;
939 struct vnode *vp = ap->a_vp;
940
941 /*
942 * Clear out the v_type field to avoid
943 * nasty things happening in vgone().
944 */
945 VOP_UNLOCK(vp);
946 vp->v_type = VNON;
947 return (0);
948 }
949
950 int
951 fdesc_reclaim(void *v)
952 {
953 struct vop_reclaim_args /* {
954 struct vnode *a_vp;
955 } */ *ap = v;
956 struct vnode *vp = ap->a_vp;
957 struct fdescnode *fd = VTOFDESC(vp);
958
959 mutex_enter(&fdcache_lock);
960 LIST_REMOVE(fd, fd_hash);
961 free(vp->v_data, M_TEMP);
962 vp->v_data = 0;
963 mutex_exit(&fdcache_lock);
964
965 return (0);
966 }
967
968 /*
969 * Return POSIX pathconf information applicable to special devices.
970 */
971 int
972 fdesc_pathconf(void *v)
973 {
974 struct vop_pathconf_args /* {
975 struct vnode *a_vp;
976 int a_name;
977 register_t *a_retval;
978 } */ *ap = v;
979
980 switch (ap->a_name) {
981 case _PC_LINK_MAX:
982 *ap->a_retval = LINK_MAX;
983 return (0);
984 case _PC_MAX_CANON:
985 *ap->a_retval = MAX_CANON;
986 return (0);
987 case _PC_MAX_INPUT:
988 *ap->a_retval = MAX_INPUT;
989 return (0);
990 case _PC_PIPE_BUF:
991 *ap->a_retval = PIPE_BUF;
992 return (0);
993 case _PC_CHOWN_RESTRICTED:
994 *ap->a_retval = 1;
995 return (0);
996 case _PC_VDISABLE:
997 *ap->a_retval = _POSIX_VDISABLE;
998 return (0);
999 case _PC_SYNC_IO:
1000 *ap->a_retval = 1;
1001 return (0);
1002 default:
1003 return (EINVAL);
1004 }
1005 /* NOTREACHED */
1006 }
1007
1008 /*
1009 * Print out the contents of a /dev/fd vnode.
1010 */
1011 /* ARGSUSED */
1012 int
1013 fdesc_print(void *v)
1014 {
1015 printf("tag VT_NON, fdesc vnode\n");
1016 return (0);
1017 }
1018
1019 int
1020 fdesc_link(void *v)
1021 {
1022 struct vop_link_args /* {
1023 struct vnode *a_dvp;
1024 struct vnode *a_vp;
1025 struct componentname *a_cnp;
1026 } */ *ap = v;
1027
1028 VOP_ABORTOP(ap->a_dvp, ap->a_cnp);
1029 vput(ap->a_dvp);
1030 return (EROFS);
1031 }
1032
1033 int
1034 fdesc_symlink(void *v)
1035 {
1036 struct vop_symlink_args /* {
1037 struct vnode *a_dvp;
1038 struct vnode **a_vpp;
1039 struct componentname *a_cnp;
1040 struct vattr *a_vap;
1041 char *a_target;
1042 } */ *ap = v;
1043
1044 VOP_ABORTOP(ap->a_dvp, ap->a_cnp);
1045 vput(ap->a_dvp);
1046 return (EROFS);
1047 }
1048