proc->thread stage 3.5: Add an IO_CORE flag so coda doesn't have to dig
[dragonfly.git] / sys / vfs / fifofs / fifo_vnops.c
CommitLineData
984263bc
MD
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 $
1de703da 35 * $DragonFly: src/sys/vfs/fifofs/fifo_vnops.c,v 1.2 2003/06/17 04:28:42 dillon Exp $
984263bc
MD
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>
53#include <miscfs/fifofs/fifo.h>
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
66static int fifo_badop __P((void));
67static int fifo_print __P((struct vop_print_args *));
68static int fifo_lookup __P((struct vop_lookup_args *));
69static int fifo_open __P((struct vop_open_args *));
70static int fifo_close __P((struct vop_close_args *));
71static int fifo_read __P((struct vop_read_args *));
72static int fifo_write __P((struct vop_write_args *));
73static int fifo_ioctl __P((struct vop_ioctl_args *));
74static int fifo_poll __P((struct vop_poll_args *));
75static int fifo_kqfilter __P((struct vop_kqfilter_args *));
76static int fifo_inactive __P((struct vop_inactive_args *));
77static int fifo_bmap __P((struct vop_bmap_args *));
78static int fifo_pathconf __P((struct vop_pathconf_args *));
79static int fifo_advlock __P((struct vop_advlock_args *));
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;
168 struct proc *a_p;
169 } */ *ap;
170{
171 struct vnode *vp = ap->a_vp;
172 struct fifoinfo *fip;
173 struct proc *p = ap->a_p;
174 struct socket *rso, *wso;
175 int error;
176
177 if ((fip = vp->v_fifoinfo) == NULL) {
178 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK);
179 vp->v_fifoinfo = fip;
180 error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0, ap->a_p);
181 if (error) {
182 free(fip, M_VNODE);
183 vp->v_fifoinfo = NULL;
184 return (error);
185 }
186 fip->fi_readsock = rso;
187 error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0, ap->a_p);
188 if (error) {
189 (void)soclose(rso);
190 free(fip, M_VNODE);
191 vp->v_fifoinfo = NULL;
192 return (error);
193 }
194 fip->fi_writesock = wso;
195 error = unp_connect2(wso, rso);
196 if (error) {
197 (void)soclose(wso);
198 (void)soclose(rso);
199 free(fip, M_VNODE);
200 vp->v_fifoinfo = NULL;
201 return (error);
202 }
203 fip->fi_readers = fip->fi_writers = 0;
204 wso->so_snd.sb_lowat = PIPE_BUF;
205 rso->so_state |= SS_CANTRCVMORE;
206 }
207 if (ap->a_mode & FREAD) {
208 fip->fi_readers++;
209 if (fip->fi_readers == 1) {
210 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
211 if (fip->fi_writers > 0) {
212 wakeup((caddr_t)&fip->fi_writers);
213 sowwakeup(fip->fi_writesock);
214 }
215 }
216 }
217 if (ap->a_mode & FWRITE) {
218 fip->fi_writers++;
219 if (fip->fi_writers == 1) {
220 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
221 if (fip->fi_readers > 0) {
222 wakeup((caddr_t)&fip->fi_readers);
223 sorwakeup(fip->fi_writesock);
224 }
225 }
226 }
227 if ((ap->a_mode & FREAD) && (ap->a_mode & O_NONBLOCK) == 0) {
228 if (fip->fi_writers == 0) {
229 VOP_UNLOCK(vp, 0, p);
230 error = tsleep((caddr_t)&fip->fi_readers,
231 PCATCH | PSOCK, "fifoor", 0);
232 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
233 if (error)
234 goto bad;
235 /*
236 * We must have got woken up because we had a writer.
237 * That (and not still having one) is the condition
238 * that we must wait for.
239 */
240 }
241 }
242 if (ap->a_mode & FWRITE) {
243 if (ap->a_mode & O_NONBLOCK) {
244 if (fip->fi_readers == 0) {
245 error = ENXIO;
246 goto bad;
247 }
248 } else {
249 if (fip->fi_readers == 0) {
250 VOP_UNLOCK(vp, 0, p);
251 error = tsleep((caddr_t)&fip->fi_writers,
252 PCATCH | PSOCK, "fifoow", 0);
253 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
254 if (error)
255 goto bad;
256 /*
257 * We must have got woken up because we had
258 * a reader. That (and not still having one)
259 * is the condition that we must wait for.
260 */
261 }
262 }
263 }
264 return (0);
265bad:
266 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, p);
267 return (error);
268}
269
270/*
271 * Vnode op for read
272 */
273/* ARGSUSED */
274static int
275fifo_read(ap)
276 struct vop_read_args /* {
277 struct vnode *a_vp;
278 struct uio *a_uio;
279 int a_ioflag;
280 struct ucred *a_cred;
281 } */ *ap;
282{
283 struct uio *uio = ap->a_uio;
284 struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock;
285 struct proc *p = uio->uio_procp;
286 int error, startresid;
287
288#ifdef DIAGNOSTIC
289 if (uio->uio_rw != UIO_READ)
290 panic("fifo_read mode");
291#endif
292 if (uio->uio_resid == 0)
293 return (0);
294 if (ap->a_ioflag & IO_NDELAY)
295 rso->so_state |= SS_NBIO;
296 startresid = uio->uio_resid;
297 VOP_UNLOCK(ap->a_vp, 0, p);
298 error = soreceive(rso, (struct sockaddr **)0, uio, (struct mbuf **)0,
299 (struct mbuf **)0, (int *)0);
300 vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY, p);
301 if (ap->a_ioflag & IO_NDELAY)
302 rso->so_state &= ~SS_NBIO;
303 return (error);
304}
305
306/*
307 * Vnode op for write
308 */
309/* ARGSUSED */
310static int
311fifo_write(ap)
312 struct vop_write_args /* {
313 struct vnode *a_vp;
314 struct uio *a_uio;
315 int a_ioflag;
316 struct ucred *a_cred;
317 } */ *ap;
318{
319 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock;
320 struct proc *p = ap->a_uio->uio_procp;
321 int error;
322
323#ifdef DIAGNOSTIC
324 if (ap->a_uio->uio_rw != UIO_WRITE)
325 panic("fifo_write mode");
326#endif
327 if (ap->a_ioflag & IO_NDELAY)
328 wso->so_state |= SS_NBIO;
329 VOP_UNLOCK(ap->a_vp, 0, p);
330 error = sosend(wso, (struct sockaddr *)0, ap->a_uio, 0,
331 (struct mbuf *)0, 0, p);
332 vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY, p);
333 if (ap->a_ioflag & IO_NDELAY)
334 wso->so_state &= ~SS_NBIO;
335 return (error);
336}
337
338/*
339 * Device ioctl operation.
340 */
341/* ARGSUSED */
342static int
343fifo_ioctl(ap)
344 struct vop_ioctl_args /* {
345 struct vnode *a_vp;
346 int a_command;
347 caddr_t a_data;
348 int a_fflag;
349 struct ucred *a_cred;
350 struct proc *a_p;
351 } */ *ap;
352{
353 struct file filetmp;
354 int error;
355
356 if (ap->a_command == FIONBIO)
357 return (0);
358 if (ap->a_fflag & FREAD) {
359 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock;
360 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p);
361 if (error)
362 return (error);
363 }
364 if (ap->a_fflag & FWRITE) {
365 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock;
366 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p);
367 if (error)
368 return (error);
369 }
370 return (0);
371}
372
373/* ARGSUSED */
374static int
375fifo_kqfilter(ap)
376 struct vop_kqfilter_args /* {
377 struct vnode *a_vp;
378 struct knote *a_kn;
379 } */ *ap;
380{
381 struct fifoinfo *fi = ap->a_vp->v_fifoinfo;
382 struct socket *so;
383 struct sockbuf *sb;
384
385 switch (ap->a_kn->kn_filter) {
386 case EVFILT_READ:
387 ap->a_kn->kn_fop = &fiforead_filtops;
388 so = fi->fi_readsock;
389 sb = &so->so_rcv;
390 break;
391 case EVFILT_WRITE:
392 ap->a_kn->kn_fop = &fifowrite_filtops;
393 so = fi->fi_writesock;
394 sb = &so->so_snd;
395 break;
396 default:
397 return (1);
398 }
399
400 ap->a_kn->kn_hook = (caddr_t)so;
401
402 SLIST_INSERT_HEAD(&sb->sb_sel.si_note, ap->a_kn, kn_selnext);
403 sb->sb_flags |= SB_KNOTE;
404
405 return (0);
406}
407
408static void
409filt_fifordetach(struct knote *kn)
410{
411 struct socket *so = (struct socket *)kn->kn_hook;
412
413 SLIST_REMOVE(&so->so_rcv.sb_sel.si_note, kn, knote, kn_selnext);
414 if (SLIST_EMPTY(&so->so_rcv.sb_sel.si_note))
415 so->so_rcv.sb_flags &= ~SB_KNOTE;
416}
417
418static int
419filt_fiforead(struct knote *kn, long hint)
420{
421 struct socket *so = (struct socket *)kn->kn_hook;
422
423 kn->kn_data = so->so_rcv.sb_cc;
424 if (so->so_state & SS_CANTRCVMORE) {
425 kn->kn_flags |= EV_EOF;
426 return (1);
427 }
428 kn->kn_flags &= ~EV_EOF;
429 return (kn->kn_data > 0);
430}
431
432static void
433filt_fifowdetach(struct knote *kn)
434{
435 struct socket *so = (struct socket *)kn->kn_hook;
436
437 SLIST_REMOVE(&so->so_snd.sb_sel.si_note, kn, knote, kn_selnext);
438 if (SLIST_EMPTY(&so->so_snd.sb_sel.si_note))
439 so->so_snd.sb_flags &= ~SB_KNOTE;
440}
441
442static int
443filt_fifowrite(struct knote *kn, long hint)
444{
445 struct socket *so = (struct socket *)kn->kn_hook;
446
447 kn->kn_data = sbspace(&so->so_snd);
448 if (so->so_state & SS_CANTSENDMORE) {
449 kn->kn_flags |= EV_EOF;
450 return (1);
451 }
452 kn->kn_flags &= ~EV_EOF;
453 return (kn->kn_data >= so->so_snd.sb_lowat);
454}
455
456/* ARGSUSED */
457static int
458fifo_poll(ap)
459 struct vop_poll_args /* {
460 struct vnode *a_vp;
461 int a_events;
462 struct ucred *a_cred;
463 struct proc *a_p;
464 } */ *ap;
465{
466 struct file filetmp;
467 int revents = 0;
468
469 if (ap->a_events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) {
470 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock;
471 if (filetmp.f_data)
472 revents |= soo_poll(&filetmp, ap->a_events, ap->a_cred,
473 ap->a_p);
474 }
475 if (ap->a_events & (POLLOUT | POLLWRNORM | POLLWRBAND)) {
476 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock;
477 if (filetmp.f_data)
478 revents |= soo_poll(&filetmp, ap->a_events, ap->a_cred,
479 ap->a_p);
480 }
481 return (revents);
482}
483
484static int
485fifo_inactive(ap)
486 struct vop_inactive_args /* {
487 struct vnode *a_vp;
488 struct proc *a_p;
489 } */ *ap;
490{
491
492 VOP_UNLOCK(ap->a_vp, 0, ap->a_p);
493 return (0);
494}
495
496/*
497 * This is a noop, simply returning what one has been given.
498 */
499static int
500fifo_bmap(ap)
501 struct vop_bmap_args /* {
502 struct vnode *a_vp;
503 daddr_t a_bn;
504 struct vnode **a_vpp;
505 daddr_t *a_bnp;
506 int *a_runp;
507 int *a_runb;
508 } */ *ap;
509{
510
511 if (ap->a_vpp != NULL)
512 *ap->a_vpp = ap->a_vp;
513 if (ap->a_bnp != NULL)
514 *ap->a_bnp = ap->a_bn;
515 if (ap->a_runp != NULL)
516 *ap->a_runp = 0;
517 if (ap->a_runb != NULL)
518 *ap->a_runb = 0;
519 return (0);
520}
521
522/*
523 * Device close routine
524 */
525/* ARGSUSED */
526static int
527fifo_close(ap)
528 struct vop_close_args /* {
529 struct vnode *a_vp;
530 int a_fflag;
531 struct ucred *a_cred;
532 struct proc *a_p;
533 } */ *ap;
534{
535 register struct vnode *vp = ap->a_vp;
536 register struct fifoinfo *fip = vp->v_fifoinfo;
537 int error1, error2;
538
539 if (ap->a_fflag & FREAD) {
540 fip->fi_readers--;
541 if (fip->fi_readers == 0)
542 socantsendmore(fip->fi_writesock);
543 }
544 if (ap->a_fflag & FWRITE) {
545 fip->fi_writers--;
546 if (fip->fi_writers == 0)
547 socantrcvmore(fip->fi_readsock);
548 }
549 if (vp->v_usecount > 1)
550 return (0);
551 error1 = soclose(fip->fi_readsock);
552 error2 = soclose(fip->fi_writesock);
553 FREE(fip, M_VNODE);
554 vp->v_fifoinfo = NULL;
555 if (error1)
556 return (error1);
557 return (error2);
558}
559
560
561/*
562 * Print out internal contents of a fifo vnode.
563 */
564int
565fifo_printinfo(vp)
566 struct vnode *vp;
567{
568 register struct fifoinfo *fip = vp->v_fifoinfo;
569
570 printf(", fifo with %ld readers and %ld writers",
571 fip->fi_readers, fip->fi_writers);
572 return (0);
573}
574
575/*
576 * Print out the contents of a fifo vnode.
577 */
578static int
579fifo_print(ap)
580 struct vop_print_args /* {
581 struct vnode *a_vp;
582 } */ *ap;
583{
584
585 printf("tag VT_NON");
586 fifo_printinfo(ap->a_vp);
587 printf("\n");
588 return (0);
589}
590
591/*
592 * Return POSIX pathconf information applicable to fifo's.
593 */
594int
595fifo_pathconf(ap)
596 struct vop_pathconf_args /* {
597 struct vnode *a_vp;
598 int a_name;
599 int *a_retval;
600 } */ *ap;
601{
602
603 switch (ap->a_name) {
604 case _PC_LINK_MAX:
605 *ap->a_retval = LINK_MAX;
606 return (0);
607 case _PC_PIPE_BUF:
608 *ap->a_retval = PIPE_BUF;
609 return (0);
610 case _PC_CHOWN_RESTRICTED:
611 *ap->a_retval = 1;
612 return (0);
613 default:
614 return (EINVAL);
615 }
616 /* NOTREACHED */
617}
618
619/*
620 * Fifo advisory byte-level locks.
621 */
622/* ARGSUSED */
623static int
624fifo_advlock(ap)
625 struct vop_advlock_args /* {
626 struct vnode *a_vp;
627 caddr_t a_id;
628 int a_op;
629 struct flock *a_fl;
630 int a_flags;
631 } */ *ap;
632{
633
634 return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL);
635}
636
637/*
638 * Fifo bad operation
639 */
640static int
641fifo_badop()
642{
643
644 panic("fifo_badop called");
645 /* NOTREACHED */
646}