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 */ 80 struct fifoinfo { 81 struct socket *fi_readsock; 82 struct socket *fi_writesock; 83 long fi_readers; 84 long fi_writers; 85 }; 86 87 static vop_print_t fifo_print; 88 static vop_open_t fifo_open; 89 static vop_close_t fifo_close; 90 static vop_ioctl_t fifo_ioctl; 91 static vop_kqfilter_t fifo_kqfilter; 92 static vop_pathconf_t fifo_pathconf; 93 static vop_advlock_t fifo_advlock; 94 95 static void filt_fifordetach(struct knote *kn); 96 static int filt_fiforead(struct knote *kn, long hint); 97 static void filt_fifowdetach(struct knote *kn); 98 static int filt_fifowrite(struct knote *kn, long hint); 99 static void filt_fifodetach_notsup(struct knote *kn); 100 static int filt_fifo_notsup(struct knote *kn, long hint); 101 102 static struct filterops fiforead_filtops = 103 { 1, NULL, filt_fifordetach, filt_fiforead }; 104 static struct filterops fifowrite_filtops = 105 { 1, NULL, filt_fifowdetach, filt_fifowrite }; 106 static struct filterops fifo_notsup_filtops = 107 { 1, NULL, filt_fifodetach_notsup, filt_fifo_notsup }; 108 109 struct vop_vector fifo_specops = { 110 .vop_default = &default_vnodeops, 111 112 .vop_access = VOP_EBADF, 113 .vop_advlock = fifo_advlock, 114 .vop_close = fifo_close, 115 .vop_create = VOP_PANIC, 116 .vop_getattr = VOP_EBADF, 117 .vop_ioctl = fifo_ioctl, 118 .vop_kqfilter = fifo_kqfilter, 119 .vop_lease = VOP_NULL, 120 .vop_link = VOP_PANIC, 121 .vop_mkdir = VOP_PANIC, 122 .vop_mknod = VOP_PANIC, 123 .vop_open = fifo_open, 124 .vop_pathconf = fifo_pathconf, 125 .vop_print = fifo_print, 126 .vop_read = VOP_PANIC, 127 .vop_readdir = VOP_PANIC, 128 .vop_readlink = VOP_PANIC, 129 .vop_reallocblks = VOP_PANIC, 130 .vop_reclaim = VOP_NULL, 131 .vop_remove = VOP_PANIC, 132 .vop_rename = VOP_PANIC, 133 .vop_rmdir = VOP_PANIC, 134 .vop_setattr = VOP_EBADF, 135 .vop_symlink = VOP_PANIC, 136 .vop_write = VOP_PANIC, 137 }; 138 139 struct mtx fifo_mtx; 140 MTX_SYSINIT(fifo, &fifo_mtx, "fifo mutex", MTX_DEF); 141 142 /* 143 * Dispose of fifo resources. 144 */ 145 static void 146 fifo_cleanup(struct vnode *vp) 147 { 148 struct fifoinfo *fip = vp->v_fifoinfo; 149 150 ASSERT_VOP_LOCKED(vp, "fifo_cleanup"); 151 if (fip->fi_readers == 0 && fip->fi_writers == 0) { 152 vp->v_fifoinfo = NULL; 153 (void)soclose(fip->fi_readsock); 154 (void)soclose(fip->fi_writesock); 155 FREE(fip, M_VNODE); 156 } 157 } 158 159 /* 160 * Open called to set up a new instance of a fifo or 161 * to find an active instance of a fifo. 162 */ 163 /* ARGSUSED */ 164 static int 165 fifo_open(ap) 166 struct vop_open_args /* { 167 struct vnode *a_vp; 168 int a_mode; 169 struct ucred *a_cred; 170 struct thread *a_td; 171 int a_fdidx; 172 } */ *ap; 173 { 174 struct vnode *vp = ap->a_vp; 175 struct fifoinfo *fip; 176 struct thread *td = ap->a_td; 177 struct ucred *cred = ap->a_cred; 178 struct socket *rso, *wso; 179 struct file *fp; 180 int error; 181 182 ASSERT_VOP_LOCKED(vp, "fifo_open"); 183 if (ap->a_fdidx < 0) 184 return (EINVAL); 185 if ((fip = vp->v_fifoinfo) == NULL) { 186 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 187 error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0, cred, td); 188 if (error) 189 goto fail1; 190 fip->fi_readsock = rso; 191 error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0, cred, td); 192 if (error) 193 goto fail2; 194 fip->fi_writesock = wso; 195 error = soconnect2(wso, rso); 196 if (error) { 197 (void)soclose(wso); 198 fail2: 199 (void)soclose(rso); 200 fail1: 201 free(fip, M_VNODE); 202 return (error); 203 } 204 fip->fi_readers = fip->fi_writers = 0; 205 wso->so_snd.sb_lowat = PIPE_BUF; 206 SOCKBUF_LOCK(&rso->so_rcv); 207 rso->so_rcv.sb_state |= SBS_CANTRCVMORE; 208 SOCKBUF_UNLOCK(&rso->so_rcv); 209 KASSERT(vp->v_fifoinfo == NULL, 210 ("fifo_open: v_fifoinfo race")); 211 vp->v_fifoinfo = fip; 212 } 213 214 /* 215 * General access to fi_readers and fi_writers is protected using 216 * the vnode lock. 217 * 218 * Protect the increment of fi_readers and fi_writers and the 219 * associated calls to wakeup() with the fifo mutex in addition 220 * to the vnode lock. This allows the vnode lock to be dropped 221 * for the msleep() calls below, and using the fifo mutex with 222 * msleep() prevents the wakeup from being missed. 223 */ 224 mtx_lock(&fifo_mtx); 225 if (ap->a_mode & FREAD) { 226 fip->fi_readers++; 227 if (fip->fi_readers == 1) { 228 SOCKBUF_LOCK(&fip->fi_writesock->so_snd); 229 fip->fi_writesock->so_snd.sb_state &= ~SBS_CANTSENDMORE; 230 SOCKBUF_UNLOCK(&fip->fi_writesock->so_snd); 231 if (fip->fi_writers > 0) { 232 wakeup(&fip->fi_writers); 233 sowwakeup(fip->fi_writesock); 234 } 235 } 236 } 237 if (ap->a_mode & FWRITE) { 238 if ((ap->a_mode & O_NONBLOCK) && fip->fi_readers == 0) { 239 mtx_unlock(&fifo_mtx); 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 } 738