Do not reset %gs in signal handlers, some programs depend on it (KDE in
[dragonfly.git] / sys / vfs / fifofs / fifo_vnops.c
CommitLineData
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1/*
2 * Copyright (c) 1990, 1993, 1995
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * @(#)fifo_vnops.c 8.10 (Berkeley) 5/27/95
34 * $FreeBSD: src/sys/miscfs/fifofs/fifo_vnops.c,v 1.45.2.4 2003/04/22 10:11:24 bde Exp $
41a01a4d 35 * $DragonFly: src/sys/vfs/fifofs/fifo_vnops.c,v 1.13 2004/03/01 06:33:20 dillon Exp $
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36 */
37
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/unistd.h>
41#include <sys/kernel.h>
42#include <sys/lock.h>
43#include <sys/malloc.h>
44#include <sys/vnode.h>
45#include <sys/socket.h>
46#include <sys/socketvar.h>
47#include <sys/filio.h>
48#include <sys/fcntl.h>
49#include <sys/file.h>
50#include <sys/event.h>
51#include <sys/poll.h>
52#include <sys/un.h>
1f2de5d4 53#include "fifo.h"
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54
55/*
56 * This structure is associated with the FIFO vnode and stores
57 * the state associated with the FIFO.
58 */
59struct fifoinfo {
60 struct socket *fi_readsock;
61 struct socket *fi_writesock;
62 long fi_readers;
63 long fi_writers;
64};
65
a6ee311a
RG
66static int fifo_badop (void);
67static int fifo_print (struct vop_print_args *);
68static int fifo_lookup (struct vop_lookup_args *);
69static int fifo_open (struct vop_open_args *);
70static int fifo_close (struct vop_close_args *);
71static int fifo_read (struct vop_read_args *);
72static int fifo_write (struct vop_write_args *);
73static int fifo_ioctl (struct vop_ioctl_args *);
74static int fifo_poll (struct vop_poll_args *);
75static int fifo_kqfilter (struct vop_kqfilter_args *);
76static int fifo_inactive (struct vop_inactive_args *);
77static int fifo_bmap (struct vop_bmap_args *);
78static int fifo_pathconf (struct vop_pathconf_args *);
79static int fifo_advlock (struct vop_advlock_args *);
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80
81static void filt_fifordetach(struct knote *kn);
82static int filt_fiforead(struct knote *kn, long hint);
83static void filt_fifowdetach(struct knote *kn);
84static int filt_fifowrite(struct knote *kn, long hint);
85
86static struct filterops fiforead_filtops =
87 { 1, NULL, filt_fifordetach, filt_fiforead };
88static struct filterops fifowrite_filtops =
89 { 1, NULL, filt_fifowdetach, filt_fifowrite };
90
91vop_t **fifo_vnodeop_p;
92static struct vnodeopv_entry_desc fifo_vnodeop_entries[] = {
93 { &vop_default_desc, (vop_t *) vop_defaultop },
94 { &vop_access_desc, (vop_t *) vop_ebadf },
95 { &vop_advlock_desc, (vop_t *) fifo_advlock },
96 { &vop_bmap_desc, (vop_t *) fifo_bmap },
97 { &vop_close_desc, (vop_t *) fifo_close },
98 { &vop_create_desc, (vop_t *) fifo_badop },
99 { &vop_getattr_desc, (vop_t *) vop_ebadf },
100 { &vop_inactive_desc, (vop_t *) fifo_inactive },
101 { &vop_ioctl_desc, (vop_t *) fifo_ioctl },
102 { &vop_kqfilter_desc, (vop_t *) fifo_kqfilter },
103 { &vop_lease_desc, (vop_t *) vop_null },
104 { &vop_link_desc, (vop_t *) fifo_badop },
105 { &vop_lookup_desc, (vop_t *) fifo_lookup },
106 { &vop_mkdir_desc, (vop_t *) fifo_badop },
107 { &vop_mknod_desc, (vop_t *) fifo_badop },
108 { &vop_open_desc, (vop_t *) fifo_open },
109 { &vop_pathconf_desc, (vop_t *) fifo_pathconf },
110 { &vop_poll_desc, (vop_t *) fifo_poll },
111 { &vop_print_desc, (vop_t *) fifo_print },
112 { &vop_read_desc, (vop_t *) fifo_read },
113 { &vop_readdir_desc, (vop_t *) fifo_badop },
114 { &vop_readlink_desc, (vop_t *) fifo_badop },
115 { &vop_reallocblks_desc, (vop_t *) fifo_badop },
116 { &vop_reclaim_desc, (vop_t *) vop_null },
117 { &vop_remove_desc, (vop_t *) fifo_badop },
118 { &vop_rename_desc, (vop_t *) fifo_badop },
119 { &vop_rmdir_desc, (vop_t *) fifo_badop },
120 { &vop_setattr_desc, (vop_t *) vop_ebadf },
121 { &vop_symlink_desc, (vop_t *) fifo_badop },
122 { &vop_write_desc, (vop_t *) fifo_write },
123 { NULL, NULL }
124};
125static struct vnodeopv_desc fifo_vnodeop_opv_desc =
126 { &fifo_vnodeop_p, fifo_vnodeop_entries };
127
128VNODEOP_SET(fifo_vnodeop_opv_desc);
129
130int
131fifo_vnoperate(ap)
132 struct vop_generic_args /* {
133 struct vnodeop_desc *a_desc;
134 <other random data follows, presumably>
135 } */ *ap;
136{
137 return (VOCALL(fifo_vnodeop_p, ap->a_desc->vdesc_offset, ap));
138}
139
140/*
141 * Trivial lookup routine that always fails.
142 */
143/* ARGSUSED */
144static int
145fifo_lookup(ap)
146 struct vop_lookup_args /* {
147 struct vnode * a_dvp;
148 struct vnode ** a_vpp;
149 struct componentname * a_cnp;
150 } */ *ap;
151{
152
153 *ap->a_vpp = NULL;
154 return (ENOTDIR);
155}
156
157/*
158 * Open called to set up a new instance of a fifo or
159 * to find an active instance of a fifo.
160 */
161/* ARGSUSED */
162static int
163fifo_open(ap)
164 struct vop_open_args /* {
165 struct vnode *a_vp;
166 int a_mode;
167 struct ucred *a_cred;
dadab5e9 168 struct thread *a_td;
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169 } */ *ap;
170{
171 struct vnode *vp = ap->a_vp;
172 struct fifoinfo *fip;
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173 struct socket *rso, *wso;
174 int error;
175
176 if ((fip = vp->v_fifoinfo) == NULL) {
177 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK);
178 vp->v_fifoinfo = fip;
dadab5e9 179 error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0, ap->a_td);
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180 if (error) {
181 free(fip, M_VNODE);
182 vp->v_fifoinfo = NULL;
183 return (error);
184 }
185 fip->fi_readsock = rso;
dadab5e9 186 error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0, ap->a_td);
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187 if (error) {
188 (void)soclose(rso);
189 free(fip, M_VNODE);
190 vp->v_fifoinfo = NULL;
191 return (error);
192 }
193 fip->fi_writesock = wso;
194 error = unp_connect2(wso, rso);
195 if (error) {
196 (void)soclose(wso);
197 (void)soclose(rso);
198 free(fip, M_VNODE);
199 vp->v_fifoinfo = NULL;
200 return (error);
201 }
202 fip->fi_readers = fip->fi_writers = 0;
203 wso->so_snd.sb_lowat = PIPE_BUF;
204 rso->so_state |= SS_CANTRCVMORE;
205 }
206 if (ap->a_mode & FREAD) {
207 fip->fi_readers++;
208 if (fip->fi_readers == 1) {
209 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
210 if (fip->fi_writers > 0) {
211 wakeup((caddr_t)&fip->fi_writers);
212 sowwakeup(fip->fi_writesock);
213 }
214 }
215 }
216 if (ap->a_mode & FWRITE) {
217 fip->fi_writers++;
218 if (fip->fi_writers == 1) {
219 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
220 if (fip->fi_readers > 0) {
221 wakeup((caddr_t)&fip->fi_readers);
222 sorwakeup(fip->fi_writesock);
223 }
224 }
225 }
226 if ((ap->a_mode & FREAD) && (ap->a_mode & O_NONBLOCK) == 0) {
227 if (fip->fi_writers == 0) {
41a01a4d 228 VOP_UNLOCK(vp, NULL, 0, ap->a_td);
984263bc 229 error = tsleep((caddr_t)&fip->fi_readers,
377d4740 230 PCATCH, "fifoor", 0);
41a01a4d 231 vn_lock(vp, NULL, LK_EXCLUSIVE | LK_RETRY, ap->a_td);
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232 if (error)
233 goto bad;
234 /*
235 * We must have got woken up because we had a writer.
236 * That (and not still having one) is the condition
237 * that we must wait for.
238 */
239 }
240 }
241 if (ap->a_mode & FWRITE) {
242 if (ap->a_mode & O_NONBLOCK) {
243 if (fip->fi_readers == 0) {
244 error = ENXIO;
245 goto bad;
246 }
247 } else {
248 if (fip->fi_readers == 0) {
41a01a4d 249 VOP_UNLOCK(vp, NULL, 0, ap->a_td);
984263bc 250 error = tsleep((caddr_t)&fip->fi_writers,
377d4740 251 PCATCH, "fifoow", 0);
41a01a4d 252 vn_lock(vp, NULL, LK_EXCLUSIVE | LK_RETRY, ap->a_td);
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253 if (error)
254 goto bad;
255 /*
256 * We must have got woken up because we had
257 * a reader. That (and not still having one)
258 * is the condition that we must wait for.
259 */
260 }
261 }
262 }
263 return (0);
264bad:
3b568787 265 VOP_CLOSE(vp, ap->a_mode, ap->a_td);
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266 return (error);
267}
268
269/*
270 * Vnode op for read
271 */
272/* ARGSUSED */
273static int
274fifo_read(ap)
275 struct vop_read_args /* {
276 struct vnode *a_vp;
277 struct uio *a_uio;
278 int a_ioflag;
279 struct ucred *a_cred;
280 } */ *ap;
281{
282 struct uio *uio = ap->a_uio;
283 struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock;
dadab5e9 284 struct thread *td = uio->uio_td;
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285 int error, startresid;
286
287#ifdef DIAGNOSTIC
288 if (uio->uio_rw != UIO_READ)
289 panic("fifo_read mode");
290#endif
291 if (uio->uio_resid == 0)
292 return (0);
293 if (ap->a_ioflag & IO_NDELAY)
294 rso->so_state |= SS_NBIO;
295 startresid = uio->uio_resid;
41a01a4d 296 VOP_UNLOCK(ap->a_vp, NULL, 0, td);
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297 error = soreceive(rso, (struct sockaddr **)0, uio, (struct mbuf **)0,
298 (struct mbuf **)0, (int *)0);
41a01a4d 299 vn_lock(ap->a_vp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
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300 if (ap->a_ioflag & IO_NDELAY)
301 rso->so_state &= ~SS_NBIO;
302 return (error);
303}
304
305/*
306 * Vnode op for write
307 */
308/* ARGSUSED */
309static int
310fifo_write(ap)
311 struct vop_write_args /* {
312 struct vnode *a_vp;
313 struct uio *a_uio;
314 int a_ioflag;
315 struct ucred *a_cred;
316 } */ *ap;
317{
318 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock;
dadab5e9 319 struct thread *td = ap->a_uio->uio_td;
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320 int error;
321
322#ifdef DIAGNOSTIC
323 if (ap->a_uio->uio_rw != UIO_WRITE)
324 panic("fifo_write mode");
325#endif
326 if (ap->a_ioflag & IO_NDELAY)
327 wso->so_state |= SS_NBIO;
41a01a4d 328 VOP_UNLOCK(ap->a_vp, NULL, 0, td);
984263bc 329 error = sosend(wso, (struct sockaddr *)0, ap->a_uio, 0,
dadab5e9 330 (struct mbuf *)0, 0, td);
41a01a4d 331 vn_lock(ap->a_vp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
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332 if (ap->a_ioflag & IO_NDELAY)
333 wso->so_state &= ~SS_NBIO;
334 return (error);
335}
336
337/*
338 * Device ioctl operation.
339 */
340/* ARGSUSED */
341static int
342fifo_ioctl(ap)
343 struct vop_ioctl_args /* {
344 struct vnode *a_vp;
345 int a_command;
346 caddr_t a_data;
347 int a_fflag;
348 struct ucred *a_cred;
dadab5e9 349 struct thread *a_td;
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350 } */ *ap;
351{
9443ca22 352 struct file filetmp; /* Local */
984263bc
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353 int error;
354
355 if (ap->a_command == FIONBIO)
356 return (0);
357 if (ap->a_fflag & FREAD) {
358 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock;
dadab5e9 359 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_td);
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MD
360 if (error)
361 return (error);
362 }
363 if (ap->a_fflag & FWRITE) {
364 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock;
dadab5e9 365 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_td);
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366 if (error)
367 return (error);
368 }
369 return (0);
370}
371
372/* ARGSUSED */
373static int
374fifo_kqfilter(ap)
375 struct vop_kqfilter_args /* {
376 struct vnode *a_vp;
377 struct knote *a_kn;
378 } */ *ap;
379{
380 struct fifoinfo *fi = ap->a_vp->v_fifoinfo;
381 struct socket *so;
382 struct sockbuf *sb;
383
384 switch (ap->a_kn->kn_filter) {
385 case EVFILT_READ:
386 ap->a_kn->kn_fop = &fiforead_filtops;
387 so = fi->fi_readsock;
388 sb = &so->so_rcv;
389 break;
390 case EVFILT_WRITE:
391 ap->a_kn->kn_fop = &fifowrite_filtops;
392 so = fi->fi_writesock;
393 sb = &so->so_snd;
394 break;
395 default:
396 return (1);
397 }
398
399 ap->a_kn->kn_hook = (caddr_t)so;
400
401 SLIST_INSERT_HEAD(&sb->sb_sel.si_note, ap->a_kn, kn_selnext);
402 sb->sb_flags |= SB_KNOTE;
403
404 return (0);
405}
406
407static void
408filt_fifordetach(struct knote *kn)
409{
410 struct socket *so = (struct socket *)kn->kn_hook;
411
412 SLIST_REMOVE(&so->so_rcv.sb_sel.si_note, kn, knote, kn_selnext);
413 if (SLIST_EMPTY(&so->so_rcv.sb_sel.si_note))
414 so->so_rcv.sb_flags &= ~SB_KNOTE;
415}
416
417static int
418filt_fiforead(struct knote *kn, long hint)
419{
420 struct socket *so = (struct socket *)kn->kn_hook;
421
422 kn->kn_data = so->so_rcv.sb_cc;
423 if (so->so_state & SS_CANTRCVMORE) {
424 kn->kn_flags |= EV_EOF;
425 return (1);
426 }
427 kn->kn_flags &= ~EV_EOF;
428 return (kn->kn_data > 0);
429}
430
431static void
432filt_fifowdetach(struct knote *kn)
433{
434 struct socket *so = (struct socket *)kn->kn_hook;
435
436 SLIST_REMOVE(&so->so_snd.sb_sel.si_note, kn, knote, kn_selnext);
437 if (SLIST_EMPTY(&so->so_snd.sb_sel.si_note))
438 so->so_snd.sb_flags &= ~SB_KNOTE;
439}
440
441static int
442filt_fifowrite(struct knote *kn, long hint)
443{
444 struct socket *so = (struct socket *)kn->kn_hook;
445
446 kn->kn_data = sbspace(&so->so_snd);
447 if (so->so_state & SS_CANTSENDMORE) {
448 kn->kn_flags |= EV_EOF;
449 return (1);
450 }
451 kn->kn_flags &= ~EV_EOF;
452 return (kn->kn_data >= so->so_snd.sb_lowat);
453}
454
455/* ARGSUSED */
456static int
457fifo_poll(ap)
458 struct vop_poll_args /* {
459 struct vnode *a_vp;
460 int a_events;
461 struct ucred *a_cred;
dadab5e9 462 struct thread *a_td;
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463 } */ *ap;
464{
465 struct file filetmp;
d08a3c4d
HP
466 int events, revents = 0;
467
630a348c 468 events = ap->a_events &
9443ca22 469 (POLLIN | POLLINIGNEOF | POLLPRI | POLLRDNORM | POLLRDBAND);
d08a3c4d
HP
470 if (events) {
471 /*
9443ca22
HP
472 * If POLLIN or POLLRDNORM is requested and POLLINIGNEOF is
473 * not, then convert the first two to the last one. This
474 * tells the socket poll function to ignore EOF so that we
475 * block if there is no writer (and no data). Callers can
476 * set POLLINIGNEOF to get non-blocking behavior.
d08a3c4d 477 */
ad4bd3a5
HP
478 if (events & (POLLIN | POLLRDNORM) &&
479 !(events & POLLINIGNEOF)) {
d08a3c4d
HP
480 events &= ~(POLLIN | POLLRDNORM);
481 events |= POLLINIGNEOF;
482 }
9443ca22 483
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484 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock;
485 if (filetmp.f_data)
d08a3c4d 486 revents |= soo_poll(&filetmp, events, ap->a_cred,
dadab5e9 487 ap->a_td);
d08a3c4d 488
9443ca22
HP
489 /* Reverse the above conversion. */
490 if ((revents & POLLINIGNEOF) &&
491 !(ap->a_events & POLLINIGNEOF)) {
492 revents |= (ap->a_events & (POLLIN | POLLRDNORM));
d08a3c4d 493 revents &= ~POLLINIGNEOF;
d08a3c4d 494 }
984263bc 495 }
d08a3c4d
HP
496 events = ap->a_events & (POLLOUT | POLLWRNORM | POLLWRBAND);
497 if (events) {
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498 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock;
499 if (filetmp.f_data)
d08a3c4d 500 revents |= soo_poll(&filetmp, events, ap->a_cred,
dadab5e9 501 ap->a_td);
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502 }
503 return (revents);
504}
505
506static int
507fifo_inactive(ap)
508 struct vop_inactive_args /* {
509 struct vnode *a_vp;
dadab5e9 510 struct thread *a_td;
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511 } */ *ap;
512{
41a01a4d 513 VOP_UNLOCK(ap->a_vp, NULL, 0, ap->a_td);
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514 return (0);
515}
516
517/*
518 * This is a noop, simply returning what one has been given.
519 */
520static int
521fifo_bmap(ap)
522 struct vop_bmap_args /* {
523 struct vnode *a_vp;
524 daddr_t a_bn;
525 struct vnode **a_vpp;
526 daddr_t *a_bnp;
527 int *a_runp;
528 int *a_runb;
529 } */ *ap;
530{
531
532 if (ap->a_vpp != NULL)
533 *ap->a_vpp = ap->a_vp;
534 if (ap->a_bnp != NULL)
535 *ap->a_bnp = ap->a_bn;
536 if (ap->a_runp != NULL)
537 *ap->a_runp = 0;
538 if (ap->a_runb != NULL)
539 *ap->a_runb = 0;
540 return (0);
541}
542
543/*
544 * Device close routine
545 */
546/* ARGSUSED */
547static int
548fifo_close(ap)
549 struct vop_close_args /* {
550 struct vnode *a_vp;
551 int a_fflag;
552 struct ucred *a_cred;
dadab5e9 553 struct thread *a_td;
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554 } */ *ap;
555{
0e99e805
RG
556 struct vnode *vp = ap->a_vp;
557 struct fifoinfo *fip = vp->v_fifoinfo;
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558 int error1, error2;
559
560 if (ap->a_fflag & FREAD) {
561 fip->fi_readers--;
562 if (fip->fi_readers == 0)
563 socantsendmore(fip->fi_writesock);
564 }
565 if (ap->a_fflag & FWRITE) {
566 fip->fi_writers--;
567 if (fip->fi_writers == 0)
568 socantrcvmore(fip->fi_readsock);
569 }
570 if (vp->v_usecount > 1)
571 return (0);
572 error1 = soclose(fip->fi_readsock);
573 error2 = soclose(fip->fi_writesock);
574 FREE(fip, M_VNODE);
575 vp->v_fifoinfo = NULL;
576 if (error1)
577 return (error1);
578 return (error2);
579}
580
581
582/*
583 * Print out internal contents of a fifo vnode.
584 */
585int
586fifo_printinfo(vp)
587 struct vnode *vp;
588{
0e99e805 589 struct fifoinfo *fip = vp->v_fifoinfo;
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590
591 printf(", fifo with %ld readers and %ld writers",
592 fip->fi_readers, fip->fi_writers);
593 return (0);
594}
595
596/*
597 * Print out the contents of a fifo vnode.
598 */
599static int
600fifo_print(ap)
601 struct vop_print_args /* {
602 struct vnode *a_vp;
603 } */ *ap;
604{
605
606 printf("tag VT_NON");
607 fifo_printinfo(ap->a_vp);
608 printf("\n");
609 return (0);
610}
611
612/*
613 * Return POSIX pathconf information applicable to fifo's.
614 */
615int
616fifo_pathconf(ap)
617 struct vop_pathconf_args /* {
618 struct vnode *a_vp;
619 int a_name;
620 int *a_retval;
621 } */ *ap;
622{
623
624 switch (ap->a_name) {
625 case _PC_LINK_MAX:
626 *ap->a_retval = LINK_MAX;
627 return (0);
628 case _PC_PIPE_BUF:
629 *ap->a_retval = PIPE_BUF;
630 return (0);
631 case _PC_CHOWN_RESTRICTED:
632 *ap->a_retval = 1;
633 return (0);
634 default:
635 return (EINVAL);
636 }
637 /* NOTREACHED */
638}
639
640/*
641 * Fifo advisory byte-level locks.
642 */
643/* ARGSUSED */
644static int
645fifo_advlock(ap)
646 struct vop_advlock_args /* {
647 struct vnode *a_vp;
648 caddr_t a_id;
649 int a_op;
650 struct flock *a_fl;
651 int a_flags;
652 } */ *ap;
653{
654
655 return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL);
656}
657
658/*
659 * Fifo bad operation
660 */
661static int
662fifo_badop()
663{
664
665 panic("fifo_badop called");
666 /* NOTREACHED */
667}