1 /*-
2 * Copyright (c) 1990, 1993, 1995
3 * The Regents of the University of California.
4 * Copyright (c) 2005 Robert N. M. Watson
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 4. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)fifo_vnops.c 8.10 (Berkeley) 5/27/95
32 * $FreeBSD$
33 */
34
35 #include <sys/param.h>
36 #include <sys/event.h>
37 #include <sys/file.h>
38 #include <sys/filedesc.h>
39 #include <sys/filio.h>
40 #include <sys/fcntl.h>
41 #include <sys/kernel.h>
42 #include <sys/lock.h>
43 #include <sys/mutex.h>
44 #include <sys/malloc.h>
45 #include <sys/poll.h>
46 #include <sys/proc.h> /* XXXKSE */
47 #include <sys/signalvar.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/sx.h>
51 #include <sys/systm.h>
52 #include <sys/un.h>
53 #include <sys/unistd.h>
54 #include <sys/vnode.h>
55 #include <fs/fifofs/fifo.h>
56
57 static fo_rdwr_t fifo_read_f;
58 static fo_rdwr_t fifo_write_f;
59 static fo_ioctl_t fifo_ioctl_f;
60 static fo_poll_t fifo_poll_f;
61 static fo_kqfilter_t fifo_kqfilter_f;
62 static fo_stat_t fifo_stat_f;
63 static fo_close_t fifo_close_f;
64
65 struct fileops fifo_ops_f = {
66 .fo_read = fifo_read_f,
67 .fo_write = fifo_write_f,
68 .fo_ioctl = fifo_ioctl_f,
69 .fo_poll = fifo_poll_f,
70 .fo_kqfilter = fifo_kqfilter_f,
71 .fo_stat = fifo_stat_f,
72 .fo_close = fifo_close_f,
73 .fo_flags = DFLAG_PASSABLE
74 };
75
76 /*
77 * This structure is associated with the FIFO vnode and stores
78 * the state associated with the FIFO.
79 * Notes about locking:
80 * - fi_readsock and fi_writesock are invariant since init time.
81 * - fi_readers and fi_writers are vnode lock protected.
82 */
83 struct fifoinfo {
84 struct socket *fi_readsock;
85 struct socket *fi_writesock;
86 long fi_readers;
87 long fi_writers;
88 };
89
90 static vop_print_t fifo_print;
91 static vop_open_t fifo_open;
92 static vop_close_t fifo_close;
93 static vop_ioctl_t fifo_ioctl;
94 static vop_kqfilter_t fifo_kqfilter;
95 static vop_pathconf_t fifo_pathconf;
96 static vop_advlock_t fifo_advlock;
97
98 static void filt_fifordetach(struct knote *kn);
99 static int filt_fiforead(struct knote *kn, long hint);
100 static void filt_fifowdetach(struct knote *kn);
101 static int filt_fifowrite(struct knote *kn, long hint);
102 static void filt_fifodetach_notsup(struct knote *kn);
103 static int filt_fifo_notsup(struct knote *kn, long hint);
104
105 static struct filterops fiforead_filtops =
106 { 1, NULL, filt_fifordetach, filt_fiforead };
107 static struct filterops fifowrite_filtops =
108 { 1, NULL, filt_fifowdetach, filt_fifowrite };
109 static struct filterops fifo_notsup_filtops =
110 { 1, NULL, filt_fifodetach_notsup, filt_fifo_notsup };
111
112 struct vop_vector fifo_specops = {
113 .vop_default = &default_vnodeops,
114
115 .vop_access = VOP_EBADF,
116 .vop_advlock = fifo_advlock,
117 .vop_close = fifo_close,
118 .vop_create = VOP_PANIC,
119 .vop_getattr = VOP_EBADF,
120 .vop_ioctl = fifo_ioctl,
121 .vop_kqfilter = fifo_kqfilter,
122 .vop_lease = VOP_NULL,
123 .vop_link = VOP_PANIC,
124 .vop_mkdir = VOP_PANIC,
125 .vop_mknod = VOP_PANIC,
126 .vop_open = fifo_open,
127 .vop_pathconf = fifo_pathconf,
128 .vop_print = fifo_print,
129 .vop_read = VOP_PANIC,
130 .vop_readdir = VOP_PANIC,
131 .vop_readlink = VOP_PANIC,
132 .vop_reallocblks = VOP_PANIC,
133 .vop_reclaim = VOP_NULL,
134 .vop_remove = VOP_PANIC,
135 .vop_rename = VOP_PANIC,
136 .vop_rmdir = VOP_PANIC,
137 .vop_setattr = VOP_EBADF,
138 .vop_symlink = VOP_PANIC,
139 .vop_write = VOP_PANIC,
140 };
141
142 struct mtx fifo_mtx;
143 MTX_SYSINIT(fifo, &fifo_mtx, "fifo mutex", MTX_DEF);
144
145 /*
146 * Dispose of fifo resources.
147 */
148 static void
149 fifo_cleanup(struct vnode *vp)
150 {
151 struct fifoinfo *fip = vp->v_fifoinfo;
152
153 ASSERT_VOP_LOCKED(vp, "fifo_cleanup");
154 if (fip->fi_readers == 0 && fip->fi_writers == 0) {
155 vp->v_fifoinfo = NULL;
156 (void)soclose(fip->fi_readsock);
157 (void)soclose(fip->fi_writesock);
158 FREE(fip, M_VNODE);
159 }
160 }
161
162 /*
163 * Open called to set up a new instance of a fifo or
164 * to find an active instance of a fifo.
165 */
166 /* ARGSUSED */
167 static int
168 fifo_open(ap)
169 struct vop_open_args /* {
170 struct vnode *a_vp;
171 int a_mode;
172 struct ucred *a_cred;
173 struct thread *a_td;
174 int a_fdidx;
175 } */ *ap;
176 {
177 struct vnode *vp = ap->a_vp;
178 struct fifoinfo *fip;
179 struct thread *td = ap->a_td;
180 struct ucred *cred = ap->a_cred;
181 struct socket *rso, *wso;
182 struct file *fp;
183 int error;
184
185 ASSERT_VOP_ELOCKED(vp, "fifo_open");
186 if (ap->a_fdidx < 0)
187 return (EINVAL);
188 if ((fip = vp->v_fifoinfo) == NULL) {
189 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK);
190 error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0, cred, td);
191 if (error)
192 goto fail1;
193 fip->fi_readsock = rso;
194 error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0, cred, td);
195 if (error)
196 goto fail2;
197 fip->fi_writesock = wso;
198 error = soconnect2(wso, rso);
199 if (error) {
200 (void)soclose(wso);
201 fail2:
202 (void)soclose(rso);
203 fail1:
204 free(fip, M_VNODE);
205 return (error);
206 }
207 fip->fi_readers = fip->fi_writers = 0;
208 wso->so_snd.sb_lowat = PIPE_BUF;
209 SOCKBUF_LOCK(&rso->so_rcv);
210 rso->so_rcv.sb_state |= SBS_CANTRCVMORE;
211 SOCKBUF_UNLOCK(&rso->so_rcv);
212 KASSERT(vp->v_fifoinfo == NULL,
213 ("fifo_open: v_fifoinfo race"));
214 vp->v_fifoinfo = fip;
215 }
216
217 /*
218 * Use the fifo_mtx lock here, in addition to the vnode lock,
219 * in order to allow vnode lock dropping before msleep() calls
220 * and still avoiding missed wakeups.
221 */
222 mtx_lock(&fifo_mtx);
223 if (ap->a_mode & FREAD) {
224 fip->fi_readers++;
225 if (fip->fi_readers == 1) {
226 SOCKBUF_LOCK(&fip->fi_writesock->so_snd);
227 fip->fi_writesock->so_snd.sb_state &= ~SBS_CANTSENDMORE;
228 SOCKBUF_UNLOCK(&fip->fi_writesock->so_snd);
229 if (fip->fi_writers > 0) {
230 wakeup(&fip->fi_writers);
231 sowwakeup(fip->fi_writesock);
232 }
233 }
234 }
235 if (ap->a_mode & FWRITE) {
236 if ((ap->a_mode & O_NONBLOCK) && fip->fi_readers == 0) {
237 mtx_unlock(&fifo_mtx);
238 if (fip->fi_writers == 0)
239 fifo_cleanup(vp);
240 return (ENXIO);
241 }
242 fip->fi_writers++;
243 if (fip->fi_writers == 1) {
244 SOCKBUF_LOCK(&fip->fi_readsock->so_rcv);
245 fip->fi_readsock->so_rcv.sb_state &= ~SBS_CANTRCVMORE;
246 SOCKBUF_UNLOCK(&fip->fi_readsock->so_rcv);
247 if (fip->fi_readers > 0) {
248 wakeup(&fip->fi_readers);
249 sorwakeup(fip->fi_readsock);
250 }
251 }
252 }
253 if ((ap->a_mode & O_NONBLOCK) == 0) {
254 if ((ap->a_mode & FREAD) && fip->fi_writers == 0) {
255 VOP_UNLOCK(vp, 0, td);
256 error = msleep(&fip->fi_readers, &fifo_mtx,
257 PDROP | PCATCH | PSOCK, "fifoor", 0);
258 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
259 if (error) {
260 fip->fi_readers--;
261 if (fip->fi_readers == 0) {
262 socantsendmore(fip->fi_writesock);
263 fifo_cleanup(vp);
264 }
265 return (error);
266 }
267 mtx_lock(&fifo_mtx);
268 /*
269 * We must have got woken up because we had a writer.
270 * That (and not still having one) is the condition
271 * that we must wait for.
272 */
273 }
274 if ((ap->a_mode & FWRITE) && fip->fi_readers == 0) {
275 VOP_UNLOCK(vp, 0, td);
276 error = msleep(&fip->fi_writers, &fifo_mtx,
277 PDROP | PCATCH | PSOCK, "fifoow", 0);
278 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
279 if (error) {
280 fip->fi_writers--;
281 if (fip->fi_writers == 0) {
282 socantrcvmore(fip->fi_readsock);
283 fifo_cleanup(vp);
284 }
285 return (error);
286 }
287 /*
288 * We must have got woken up because we had
289 * a reader. That (and not still having one)
290 * is the condition that we must wait for.
291 */
292 mtx_lock(&fifo_mtx);
293 }
294 }
295 mtx_unlock(&fifo_mtx);
296 KASSERT(ap->a_fdidx >= 0, ("can't fifo/vnode bypass %d", ap->a_fdidx));
297 fp = ap->a_td->td_proc->p_fd->fd_ofiles[ap->a_fdidx];
298 KASSERT(fp->f_ops == &badfileops, ("not badfileops in fifo_open"));
299 fp->f_ops = &fifo_ops_f;
300 fp->f_data = fip;
301 return (0);
302 }
303
304 /*
305 * Now unused vnode ioctl routine.
306 */
307 /* ARGSUSED */
308 static int
309 fifo_ioctl(ap)
310 struct vop_ioctl_args /* {
311 struct vnode *a_vp;
312 u_long a_command;
313 caddr_t a_data;
314 int a_fflag;
315 struct ucred *a_cred;
316 struct thread *a_td;
317 } */ *ap;
318 {
319
320 printf("WARNING: fifo_ioctl called unexpectedly\n");
321 return (ENOTTY);
322 }
323
324 /*
325 * Now unused vnode kqfilter routine.
326 */
327 /* ARGSUSED */
328 static int
329 fifo_kqfilter(ap)
330 struct vop_kqfilter_args /* {
331 struct vnode *a_vp;
332 struct knote *a_kn;
333 } */ *ap;
334 {
335
336 printf("WARNING: fifo_kqfilter called unexpectedly\n");
337 return (EINVAL);
338 }
339
340 static void
341 filt_fifordetach(struct knote *kn)
342 {
343 struct socket *so = (struct socket *)kn->kn_hook;
344
345 SOCKBUF_LOCK(&so->so_rcv);
346 knlist_remove(&so->so_rcv.sb_sel.si_note, kn, 1);
347 if (knlist_empty(&so->so_rcv.sb_sel.si_note))
348 so->so_rcv.sb_flags &= ~SB_KNOTE;
349 SOCKBUF_UNLOCK(&so->so_rcv);
350 }
351
352 static int
353 filt_fiforead(struct knote *kn, long hint)
354 {
355 struct socket *so = (struct socket *)kn->kn_hook;
356
357 SOCKBUF_LOCK_ASSERT(&so->so_rcv);
358 kn->kn_data = so->so_rcv.sb_cc;
359 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
360 kn->kn_flags |= EV_EOF;
361 return (1);
362 } else {
363 kn->kn_flags &= ~EV_EOF;
364 return (kn->kn_data > 0);
365 }
366 }
367
368 static void
369 filt_fifowdetach(struct knote *kn)
370 {
371 struct socket *so = (struct socket *)kn->kn_hook;
372
373 SOCKBUF_LOCK(&so->so_snd);
374 knlist_remove(&so->so_snd.sb_sel.si_note, kn, 1);
375 if (knlist_empty(&so->so_snd.sb_sel.si_note))
376 so->so_snd.sb_flags &= ~SB_KNOTE;
377 SOCKBUF_UNLOCK(&so->so_snd);
378 }
379
380 static int
381 filt_fifowrite(struct knote *kn, long hint)
382 {
383 struct socket *so = (struct socket *)kn->kn_hook;
384
385 SOCKBUF_LOCK_ASSERT(&so->so_snd);
386 kn->kn_data = sbspace(&so->so_snd);
387 if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
388 kn->kn_flags |= EV_EOF;
389 return (1);
390 } else {
391 kn->kn_flags &= ~EV_EOF;
392 return (kn->kn_data >= so->so_snd.sb_lowat);
393 }
394 }
395
396 static void
397 filt_fifodetach_notsup(struct knote *kn)
398 {
399
400 }
401
402 static int
403 filt_fifo_notsup(struct knote *kn, long hint)
404 {
405
406 return (0);
407 }
408
409 /*
410 * Device close routine
411 */
412 /* ARGSUSED */
413 static int
414 fifo_close(ap)
415 struct vop_close_args /* {
416 struct vnode *a_vp;
417 int a_fflag;
418 struct ucred *a_cred;
419 struct thread *a_td;
420 } */ *ap;
421 {
422 struct vnode *vp = ap->a_vp;
423 struct fifoinfo *fip = vp->v_fifoinfo;
424
425 ASSERT_VOP_LOCKED(vp, "fifo_close");
426 KASSERT(fip != NULL, ("fifo_close: no v_fifoinfo"));
427 if (ap->a_fflag & FREAD) {
428 fip->fi_readers--;
429 if (fip->fi_readers == 0)
430 socantsendmore(fip->fi_writesock);
431 }
432 if (ap->a_fflag & FWRITE) {
433 fip->fi_writers--;
434 if (fip->fi_writers == 0)
435 socantrcvmore(fip->fi_readsock);
436 }
437 fifo_cleanup(vp);
438 return (0);
439 }
440
441 /*
442 * Print out internal contents of a fifo vnode.
443 */
444 int
445 fifo_printinfo(vp)
446 struct vnode *vp;
447 {
448 register struct fifoinfo *fip = vp->v_fifoinfo;
449
450 printf(", fifo with %ld readers and %ld writers",
451 fip->fi_readers, fip->fi_writers);
452 return (0);
453 }
454
455 /*
456 * Print out the contents of a fifo vnode.
457 */
458 static int
459 fifo_print(ap)
460 struct vop_print_args /* {
461 struct vnode *a_vp;
462 } */ *ap;
463 {
464 fifo_printinfo(ap->a_vp);
465 printf("\n");
466 return (0);
467 }
468
469 /*
470 * Return POSIX pathconf information applicable to fifo's.
471 */
472 static int
473 fifo_pathconf(ap)
474 struct vop_pathconf_args /* {
475 struct vnode *a_vp;
476 int a_name;
477 int *a_retval;
478 } */ *ap;
479 {
480
481 switch (ap->a_name) {
482 case _PC_LINK_MAX:
483 *ap->a_retval = LINK_MAX;
484 return (0);
485 case _PC_PIPE_BUF:
486 *ap->a_retval = PIPE_BUF;
487 return (0);
488 case _PC_CHOWN_RESTRICTED:
489 *ap->a_retval = 1;
490 return (0);
491 default:
492 return (EINVAL);
493 }
494 /* NOTREACHED */
495 }
496
497 /*
498 * Fifo advisory byte-level locks.
499 */
500 /* ARGSUSED */
501 static int
502 fifo_advlock(ap)
503 struct vop_advlock_args /* {
504 struct vnode *a_vp;
505 caddr_t a_id;
506 int a_op;
507 struct flock *a_fl;
508 int a_flags;
509 } */ *ap;
510 {
511
512 return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL);
513 }
514
515 static int
516 fifo_close_f(struct file *fp, struct thread *td)
517 {
518
519 return (vnops.fo_close(fp, td));
520 }
521
522 /*
523 * The implementation of ioctl() for named fifos is complicated by the fact
524 * that we permit O_RDWR fifo file descriptors, meaning that the actions of
525 * ioctls may have to be applied to both the underlying sockets rather than
526 * just one. The original implementation simply forward the ioctl to one
527 * or both sockets based on fp->f_flag. We now consider each ioctl
528 * separately, as the composition effect requires careful ordering.
529 *
530 * We do not blindly pass all ioctls through to the socket in order to avoid
531 * providing unnecessary ioctls that might be improperly depended on by
532 * applications (such as socket-specific, routing, and interface ioctls).
533 *
534 * Unlike sys_pipe.c, fifos do not implement the deprecated TIOCSPGRP and
535 * TIOCGPGRP ioctls. Earlier implementations of fifos did forward SIOCSPGRP
536 * and SIOCGPGRP ioctls, so we might need to re-add those here.
537 */
538 static int
539 fifo_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred,
540 struct thread *td)
541 {
542 struct fifoinfo *fi;
543 struct file filetmp; /* Local, so need not be locked. */
544 int error;
545
546 error = ENOTTY;
547 fi = fp->f_data;
548
549 switch (com) {
550 case FIONBIO:
551 /*
552 * Non-blocking I/O is implemented at the fifo layer using
553 * MSG_NBIO, so does not need to be forwarded down the stack.
554 */
555 return (0);
556
557 case FIOASYNC:
558 case FIOSETOWN:
559 case FIOGETOWN:
560 /*
561 * These socket ioctls don't have any ordering requirements,
562 * so are called in an arbitrary order, and only on the
563 * sockets indicated by the file descriptor rights.
564 *
565 * XXXRW: If O_RDWR and the read socket accepts an ioctl but
566 * the write socket doesn't, the socketpair is left in an
567 * inconsistent state.
568 */
569 if (fp->f_flag & FREAD) {
570 filetmp.f_data = fi->fi_readsock;
571 filetmp.f_cred = cred;
572 error = soo_ioctl(&filetmp, com, data, cred, td);
573 if (error)
574 return (error);
575 }
576 if (fp->f_flag & FWRITE) {
577 filetmp.f_data = fi->fi_writesock;
578 filetmp.f_cred = cred;
579 error = soo_ioctl(&filetmp, com, data, cred, td);
580 }
581 return (error);
582
583 case FIONREAD:
584 /*
585 * FIONREAD will return 0 for non-readable descriptors, and
586 * the results of FIONREAD on the read socket for readable
587 * descriptors.
588 */
589 if (!(fp->f_flag & FREAD)) {
590 *(int *)data = 0;
591 return (0);
592 }
593 filetmp.f_data = fi->fi_readsock;
594 filetmp.f_cred = cred;
595 return (soo_ioctl(&filetmp, com, data, cred, td));
596
597 default:
598 return (ENOTTY);
599 }
600 }
601
602 /*
603 * Because fifos are now a file descriptor layer object, EVFILT_VNODE is not
604 * implemented. Likely, fifo_kqfilter() should be removed, and
605 * fifo_kqfilter_f() should know how to forward the request to the underling
606 * vnode using f_vnode in the file descriptor here.
607 */
608 static int
609 fifo_kqfilter_f(struct file *fp, struct knote *kn)
610 {
611 struct fifoinfo *fi;
612 struct socket *so;
613 struct sockbuf *sb;
614
615 fi = fp->f_data;
616
617 /*
618 * If a filter is requested that is not supported by this file
619 * descriptor, don't return an error, but also don't ever generate an
620 * event.
621 */
622 if ((kn->kn_filter == EVFILT_READ) && !(fp->f_flag & FREAD)) {
623 kn->kn_fop = &fifo_notsup_filtops;
624 return (0);
625 }
626
627 if ((kn->kn_filter == EVFILT_WRITE) && !(fp->f_flag & FWRITE)) {
628 kn->kn_fop = &fifo_notsup_filtops;
629 return (0);
630 }
631
632 switch (kn->kn_filter) {
633 case EVFILT_READ:
634 kn->kn_fop = &fiforead_filtops;
635 so = fi->fi_readsock;
636 sb = &so->so_rcv;
637 break;
638 case EVFILT_WRITE:
639 kn->kn_fop = &fifowrite_filtops;
640 so = fi->fi_writesock;
641 sb = &so->so_snd;
642 break;
643 default:
644 return (EINVAL);
645 }
646
647 kn->kn_hook = (caddr_t)so;
648
649 SOCKBUF_LOCK(sb);
650 knlist_add(&sb->sb_sel.si_note, kn, 1);
651 sb->sb_flags |= SB_KNOTE;
652 SOCKBUF_UNLOCK(sb);
653
654 return (0);
655 }
656
657 static int
658 fifo_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td)
659 {
660 struct fifoinfo *fip;
661 struct file filetmp;
662 int levents, revents = 0;
663
664 fip = fp->f_data;
665 levents = events &
666 (POLLIN | POLLINIGNEOF | POLLPRI | POLLRDNORM | POLLRDBAND);
667 if ((fp->f_flag & FREAD) && levents) {
668 /*
669 * If POLLIN or POLLRDNORM is requested and POLLINIGNEOF is
670 * not, then convert the first two to the last one. This
671 * tells the socket poll function to ignore EOF so that we
672 * block if there is no writer (and no data). Callers can
673 * set POLLINIGNEOF to get non-blocking behavior.
674 */
675 if (levents & (POLLIN | POLLRDNORM) &&
676 !(levents & POLLINIGNEOF)) {
677 levents &= ~(POLLIN | POLLRDNORM);
678 levents |= POLLINIGNEOF;
679 }
680
681 filetmp.f_data = fip->fi_readsock;
682 filetmp.f_cred = cred;
683 revents |= soo_poll(&filetmp, levents, cred, td);
684
685 /* Reverse the above conversion. */
686 if ((revents & POLLINIGNEOF) && !(events & POLLINIGNEOF)) {
687 revents |= (events & (POLLIN | POLLRDNORM));
688 revents &= ~POLLINIGNEOF;
689 }
690 }
691 levents = events & (POLLOUT | POLLWRNORM | POLLWRBAND);
692 if ((fp->f_flag & FWRITE) && levents) {
693 filetmp.f_data = fip->fi_writesock;
694 filetmp.f_cred = cred;
695 revents |= soo_poll(&filetmp, levents, cred, td);
696 }
697 return (revents);
698 }
699
700 static int
701 fifo_read_f(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct thread *td)
702 {
703 struct fifoinfo *fip;
704 int error, sflags;
705
706 fip = fp->f_data;
707 KASSERT(uio->uio_rw == UIO_READ,("fifo_read mode"));
708 if (uio->uio_resid == 0)
709 return (0);
710 sflags = (fp->f_flag & FNONBLOCK) ? MSG_NBIO : 0;
711 mtx_lock(&Giant);
712 error = soreceive(fip->fi_readsock, NULL, uio, NULL, NULL, &sflags);
713 mtx_unlock(&Giant);
714 return (error);
715 }
716
717 static int
718 fifo_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td)
719 {
720
721 return (vnops.fo_stat(fp, sb, cred, td));
722 }
723
724 static int
725 fifo_write_f(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct thread *td)
726 {
727 struct fifoinfo *fip;
728 int error, sflags;
729
730 fip = fp->f_data;
731 KASSERT(uio->uio_rw == UIO_WRITE,("fifo_write mode"));
732 sflags = (fp->f_flag & FNONBLOCK) ? MSG_NBIO : 0;
733 mtx_lock(&Giant);
734 error = sosend(fip->fi_writesock, NULL, uio, 0, NULL, sflags, td);
735 mtx_unlock(&Giant);
736 return (error);
737 }
Cache object: 886417ed3477942ca48949b9ae104a6f
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