1 /* $NetBSD: kern_event.c,v 1.46 2008/01/23 15:04:39 elad Exp $ */ 2 3 /*- 4 * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org> 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD: src/sys/kern/kern_event.c,v 1.27 2001/07/05 17:10:44 rwatson Exp $ 29 */ 30 31 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: kern_event.c,v 1.46 2008/01/23 15:04:39 elad Exp $"); 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/kernel.h> 37 #include <sys/proc.h> 38 #include <sys/malloc.h> 39 #include <sys/unistd.h> 40 #include <sys/file.h> 41 #include <sys/fcntl.h> 42 #include <sys/select.h> 43 #include <sys/queue.h> 44 #include <sys/event.h> 45 #include <sys/eventvar.h> 46 #include <sys/poll.h> 47 #include <sys/pool.h> 48 #include <sys/protosw.h> 49 #include <sys/socket.h> 50 #include <sys/socketvar.h> 51 #include <sys/stat.h> 52 #include <sys/uio.h> 53 #include <sys/mount.h> 54 #include <sys/filedesc.h> 55 #include <sys/syscallargs.h> 56 #include <sys/kauth.h> 57 #include <sys/conf.h> 58 59 static void kqueue_wakeup(struct kqueue *kq); 60 61 static int kqueue_scan(struct file *, size_t, struct kevent *, 62 const struct timespec *, struct lwp *, register_t *, 63 const struct kevent_ops *); 64 static int kqueue_read(struct file *fp, off_t *offset, struct uio *uio, 65 kauth_cred_t cred, int flags); 66 static int kqueue_write(struct file *fp, off_t *offset, struct uio *uio, 67 kauth_cred_t cred, int flags); 68 static int kqueue_ioctl(struct file *fp, u_long com, void *data, 69 struct lwp *l); 70 static int kqueue_fcntl(struct file *fp, u_int com, void *data, 71 struct lwp *l); 72 static int kqueue_poll(struct file *fp, int events, struct lwp *l); 73 static int kqueue_kqfilter(struct file *fp, struct knote *kn); 74 static int kqueue_stat(struct file *fp, struct stat *sp, struct lwp *l); 75 static int kqueue_close(struct file *fp, struct lwp *l); 76 77 static const struct fileops kqueueops = { 78 kqueue_read, kqueue_write, kqueue_ioctl, kqueue_fcntl, kqueue_poll, 79 kqueue_stat, kqueue_close, kqueue_kqfilter 80 }; 81 82 static void knote_attach(struct knote *kn, struct filedesc *fdp); 83 static void knote_drop(struct knote *kn, struct lwp *l, 84 struct filedesc *fdp); 85 static void knote_enqueue(struct knote *kn); 86 static void knote_dequeue(struct knote *kn); 87 88 static void filt_kqdetach(struct knote *kn); 89 static int filt_kqueue(struct knote *kn, long hint); 90 static int filt_procattach(struct knote *kn); 91 static void filt_procdetach(struct knote *kn); 92 static int filt_proc(struct knote *kn, long hint); 93 static int filt_fileattach(struct knote *kn); 94 static void filt_timerexpire(void *knx); 95 static int filt_timerattach(struct knote *kn); 96 static void filt_timerdetach(struct knote *kn); 97 static int filt_timer(struct knote *kn, long hint); 98 99 static const struct filterops kqread_filtops = 100 { 1, NULL, filt_kqdetach, filt_kqueue }; 101 static const struct filterops proc_filtops = 102 { 0, filt_procattach, filt_procdetach, filt_proc }; 103 static const struct filterops file_filtops = 104 { 1, filt_fileattach, NULL, NULL }; 105 static const struct filterops timer_filtops = 106 { 0, filt_timerattach, filt_timerdetach, filt_timer }; 107 108 static POOL_INIT(kqueue_pool, sizeof(struct kqueue), 0, 0, 0, "kqueuepl", NULL, 109 IPL_VM); 110 static POOL_INIT(knote_pool, sizeof(struct knote), 0, 0, 0, "knotepl", NULL, 111 IPL_VM); 112 static int kq_ncallouts = 0; 113 static int kq_calloutmax = (4 * 1024); 114 115 MALLOC_DEFINE(M_KEVENT, "kevent", "kevents/knotes"); 116 117 #define KNOTE_ACTIVATE(kn) \ 118 do { \ 119 kn->kn_status |= KN_ACTIVE; \ 120 if ((kn->kn_status & (KN_QUEUED | KN_DISABLED)) == 0) \ 121 knote_enqueue(kn); \ 122 } while(0) 123 124 #define KN_HASHSIZE 64 /* XXX should be tunable */ 125 #define KN_HASH(val, mask) (((val) ^ (val >> 8)) & (mask)) 126 127 extern const struct filterops sig_filtops; 128 129 /* 130 * Table for for all system-defined filters. 131 * These should be listed in the numeric order of the EVFILT_* defines. 132 * If filtops is NULL, the filter isn't implemented in NetBSD. 133 * End of list is when name is NULL. 134 */ 135 struct kfilter { 136 const char *name; /* name of filter */ 137 uint32_t filter; /* id of filter */ 138 const struct filterops *filtops;/* operations for filter */ 139 }; 140 141 /* System defined filters */ 142 static const struct kfilter sys_kfilters[] = { 143 { "EVFILT_READ", EVFILT_READ, &file_filtops }, 144 { "EVFILT_WRITE", EVFILT_WRITE, &file_filtops }, 145 { "EVFILT_AIO", EVFILT_AIO, NULL }, 146 { "EVFILT_VNODE", EVFILT_VNODE, &file_filtops }, 147 { "EVFILT_PROC", EVFILT_PROC, &proc_filtops }, 148 { "EVFILT_SIGNAL", EVFILT_SIGNAL, &sig_filtops }, 149 { "EVFILT_TIMER", EVFILT_TIMER, &timer_filtops }, 150 { NULL, 0, NULL }, /* end of list */ 151 }; 152 153 /* User defined kfilters */ 154 static struct kfilter *user_kfilters; /* array */ 155 static int user_kfilterc; /* current offset */ 156 static int user_kfiltermaxc; /* max size so far */ 157 158 /* 159 * Find kfilter entry by name, or NULL if not found. 160 */ 161 static const struct kfilter * 162 kfilter_byname_sys(const char *name) 163 { 164 int i; 165 166 for (i = 0; sys_kfilters[i].name != NULL; i++) { 167 if (strcmp(name, sys_kfilters[i].name) == 0) 168 return (&sys_kfilters[i]); 169 } 170 return (NULL); 171 } 172 173 static struct kfilter * 174 kfilter_byname_user(const char *name) 175 { 176 int i; 177 178 /* user filter slots have a NULL name if previously deregistered */ 179 for (i = 0; i < user_kfilterc ; i++) { 180 if (user_kfilters[i].name != NULL && 181 strcmp(name, user_kfilters[i].name) == 0) 182 return (&user_kfilters[i]); 183 } 184 return (NULL); 185 } 186 187 static const struct kfilter * 188 kfilter_byname(const char *name) 189 { 190 const struct kfilter *kfilter; 191 192 if ((kfilter = kfilter_byname_sys(name)) != NULL) 193 return (kfilter); 194 195 return (kfilter_byname_user(name)); 196 } 197 198 /* 199 * Find kfilter entry by filter id, or NULL if not found. 200 * Assumes entries are indexed in filter id order, for speed. 201 */ 202 static const struct kfilter * 203 kfilter_byfilter(uint32_t filter) 204 { 205 const struct kfilter *kfilter; 206 207 if (filter < EVFILT_SYSCOUNT) /* it's a system filter */ 208 kfilter = &sys_kfilters[filter]; 209 else if (user_kfilters != NULL && 210 filter < EVFILT_SYSCOUNT + user_kfilterc) 211 /* it's a user filter */ 212 kfilter = &user_kfilters[filter - EVFILT_SYSCOUNT]; 213 else 214 return (NULL); /* out of range */ 215 KASSERT(kfilter->filter == filter); /* sanity check! */ 216 return (kfilter); 217 } 218 219 /* 220 * Register a new kfilter. Stores the entry in user_kfilters. 221 * Returns 0 if operation succeeded, or an appropriate errno(2) otherwise. 222 * If retfilter != NULL, the new filterid is returned in it. 223 */ 224 int 225 kfilter_register(const char *name, const struct filterops *filtops, 226 int *retfilter) 227 { 228 struct kfilter *kfilter; 229 void *space; 230 int len; 231 int i; 232 233 if (name == NULL || name[0] == '\0' || filtops == NULL) 234 return (EINVAL); /* invalid args */ 235 if (kfilter_byname(name) != NULL) 236 return (EEXIST); /* already exists */ 237 if (user_kfilterc > 0xffffffff - EVFILT_SYSCOUNT) 238 return (EINVAL); /* too many */ 239 240 for (i = 0; i < user_kfilterc; i++) { 241 kfilter = &user_kfilters[i]; 242 if (kfilter->name == NULL) { 243 /* Previously deregistered slot. Reuse. */ 244 goto reuse; 245 } 246 } 247 248 /* check if need to grow user_kfilters */ 249 if (user_kfilterc + 1 > user_kfiltermaxc) { 250 /* 251 * Grow in KFILTER_EXTENT chunks. Use malloc(9), because we 252 * want to traverse user_kfilters as an array. 253 */ 254 user_kfiltermaxc += KFILTER_EXTENT; 255 kfilter = malloc(user_kfiltermaxc * sizeof(struct filter *), 256 M_KEVENT, M_WAITOK); 257 258 /* copy existing user_kfilters */ 259 if (user_kfilters != NULL) 260 memcpy((void *)kfilter, (void *)user_kfilters, 261 user_kfilterc * sizeof(struct kfilter *)); 262 /* zero new sections */ 263 memset((char *)kfilter + 264 user_kfilterc * sizeof(struct kfilter *), 0, 265 (user_kfiltermaxc - user_kfilterc) * 266 sizeof(struct kfilter *)); 267 /* switch to new kfilter */ 268 if (user_kfilters != NULL) 269 free(user_kfilters, M_KEVENT); 270 user_kfilters = kfilter; 271 } 272 /* Adding new slot */ 273 kfilter = &user_kfilters[user_kfilterc++]; 274 reuse: 275 len = strlen(name) + 1; /* copy name */ 276 space = malloc(len, M_KEVENT, M_WAITOK); 277 memcpy(space, name, len); 278 kfilter->name = space; 279 280 kfilter->filter = (kfilter - user_kfilters) + EVFILT_SYSCOUNT; 281 282 len = sizeof(struct filterops); /* copy filtops */ 283 space = malloc(len, M_KEVENT, M_WAITOK); 284 memcpy(space, filtops, len); 285 kfilter->filtops = space; 286 287 if (retfilter != NULL) 288 *retfilter = kfilter->filter; 289 return (0); 290 } 291 292 /* 293 * Unregister a kfilter previously registered with kfilter_register. 294 * This retains the filter id, but clears the name and frees filtops (filter 295 * operations), so that the number isn't reused during a boot. 296 * Returns 0 if operation succeeded, or an appropriate errno(2) otherwise. 297 */ 298 int 299 kfilter_unregister(const char *name) 300 { 301 struct kfilter *kfilter; 302 303 if (name == NULL || name[0] == '\0') 304 return (EINVAL); /* invalid name */ 305 306 if (kfilter_byname_sys(name) != NULL) 307 return (EINVAL); /* can't detach system filters */ 308 309 kfilter = kfilter_byname_user(name); 310 if (kfilter == NULL) /* not found */ 311 return (ENOENT); 312 313 /* XXXUNCONST Cast away const (but we know it's safe. */ 314 free(__UNCONST(kfilter->name), M_KEVENT); 315 kfilter->name = NULL; /* mark as `not implemented' */ 316 317 if (kfilter->filtops != NULL) { 318 /* XXXUNCONST Cast away const (but we know it's safe. */ 319 free(__UNCONST(kfilter->filtops), M_KEVENT); 320 kfilter->filtops = NULL; /* mark as `not implemented' */ 321 } 322 return (0); 323 } 324 325 326 /* 327 * Filter attach method for EVFILT_READ and EVFILT_WRITE on normal file 328 * descriptors. Calls struct fileops kqfilter method for given file descriptor. 329 */ 330 static int 331 filt_fileattach(struct knote *kn) 332 { 333 struct file *fp; 334 335 fp = kn->kn_fp; 336 return ((*fp->f_ops->fo_kqfilter)(fp, kn)); 337 } 338 339 /* 340 * Filter detach method for EVFILT_READ on kqueue descriptor. 341 */ 342 static void 343 filt_kqdetach(struct knote *kn) 344 { 345 struct kqueue *kq; 346 347 kq = (struct kqueue *)kn->kn_fp->f_data; 348 SLIST_REMOVE(&kq->kq_sel.sel_klist, kn, knote, kn_selnext); 349 } 350 351 /* 352 * Filter event method for EVFILT_READ on kqueue descriptor. 353 */ 354 /*ARGSUSED*/ 355 static int 356 filt_kqueue(struct knote *kn, long hint) 357 { 358 struct kqueue *kq; 359 360 kq = (struct kqueue *)kn->kn_fp->f_data; 361 kn->kn_data = kq->kq_count; 362 return (kn->kn_data > 0); 363 } 364 365 /* 366 * Filter attach method for EVFILT_PROC. 367 */ 368 static int 369 filt_procattach(struct knote *kn) 370 { 371 struct proc *p, *curp; 372 struct lwp *curl; 373 374 curl = curlwp; 375 curp = curl->l_proc; 376 377 p = pfind(kn->kn_id); 378 if (p == NULL) 379 return (ESRCH); 380 381 /* 382 * Fail if it's not owned by you, or the last exec gave us 383 * setuid/setgid privs (unless you're root). 384 */ 385 if (kauth_authorize_process(curl->l_cred, KAUTH_PROCESS_KEVENT_FILTER, 386 p, NULL, NULL, NULL) != 0) 387 return (EACCES); 388 389 kn->kn_ptr.p_proc = p; 390 kn->kn_flags |= EV_CLEAR; /* automatically set */ 391 392 /* 393 * internal flag indicating registration done by kernel 394 */ 395 if (kn->kn_flags & EV_FLAG1) { 396 kn->kn_data = kn->kn_sdata; /* ppid */ 397 kn->kn_fflags = NOTE_CHILD; 398 kn->kn_flags &= ~EV_FLAG1; 399 } 400 401 /* XXXSMP lock the process? */ 402 SLIST_INSERT_HEAD(&p->p_klist, kn, kn_selnext); 403 404 return (0); 405 } 406 407 /* 408 * Filter detach method for EVFILT_PROC. 409 * 410 * The knote may be attached to a different process, which may exit, 411 * leaving nothing for the knote to be attached to. So when the process 412 * exits, the knote is marked as DETACHED and also flagged as ONESHOT so 413 * it will be deleted when read out. However, as part of the knote deletion, 414 * this routine is called, so a check is needed to avoid actually performing 415 * a detach, because the original process might not exist any more. 416 */ 417 static void 418 filt_procdetach(struct knote *kn) 419 { 420 struct proc *p; 421 422 if (kn->kn_status & KN_DETACHED) 423 return; 424 425 p = kn->kn_ptr.p_proc; 426 427 /* XXXSMP lock the process? */ 428 SLIST_REMOVE(&p->p_klist, kn, knote, kn_selnext); 429 } 430 431 /* 432 * Filter event method for EVFILT_PROC. 433 */ 434 static int 435 filt_proc(struct knote *kn, long hint) 436 { 437 u_int event; 438 439 /* 440 * mask off extra data 441 */ 442 event = (u_int)hint & NOTE_PCTRLMASK; 443 444 /* 445 * if the user is interested in this event, record it. 446 */ 447 if (kn->kn_sfflags & event) 448 kn->kn_fflags |= event; 449 450 /* 451 * process is gone, so flag the event as finished. 452 */ 453 if (event == NOTE_EXIT) { 454 /* 455 * Detach the knote from watched process and mark 456 * it as such. We can't leave this to kqueue_scan(), 457 * since the process might not exist by then. And we 458 * have to do this now, since psignal KNOTE() is called 459 * also for zombies and we might end up reading freed 460 * memory if the kevent would already be picked up 461 * and knote g/c'ed. 462 */ 463 kn->kn_fop->f_detach(kn); 464 kn->kn_status |= KN_DETACHED; 465 466 /* Mark as ONESHOT, so that the knote it g/c'ed when read */ 467 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 468 return (1); 469 } 470 471 /* 472 * process forked, and user wants to track the new process, 473 * so attach a new knote to it, and immediately report an 474 * event with the parent's pid. 475 */ 476 if ((event == NOTE_FORK) && (kn->kn_sfflags & NOTE_TRACK)) { 477 struct kevent kev; 478 int error; 479 480 /* 481 * register knote with new process. 482 */ 483 kev.ident = hint & NOTE_PDATAMASK; /* pid */ 484 kev.filter = kn->kn_filter; 485 kev.flags = kn->kn_flags | EV_ADD | EV_ENABLE | EV_FLAG1; 486 kev.fflags = kn->kn_sfflags; 487 kev.data = kn->kn_id; /* parent */ 488 kev.udata = kn->kn_kevent.udata; /* preserve udata */ 489 error = kqueue_register(kn->kn_kq, &kev, NULL); 490 if (error) 491 kn->kn_fflags |= NOTE_TRACKERR; 492 } 493 494 return (kn->kn_fflags != 0); 495 } 496 497 static void 498 filt_timerexpire(void *knx) 499 { 500 struct knote *kn = knx; 501 int tticks; 502 503 kn->kn_data++; 504 KNOTE_ACTIVATE(kn); 505 506 if ((kn->kn_flags & EV_ONESHOT) == 0) { 507 tticks = mstohz(kn->kn_sdata); 508 callout_schedule((callout_t *)kn->kn_hook, tticks); 509 } 510 } 511 512 /* 513 * data contains amount of time to sleep, in milliseconds 514 */ 515 static int 516 filt_timerattach(struct knote *kn) 517 { 518 callout_t *calloutp; 519 int tticks; 520 521 if (kq_ncallouts >= kq_calloutmax) 522 return (ENOMEM); 523 kq_ncallouts++; 524 525 tticks = mstohz(kn->kn_sdata); 526 527 /* if the supplied value is under our resolution, use 1 tick */ 528 if (tticks == 0) { 529 if (kn->kn_sdata == 0) 530 return (EINVAL); 531 tticks = 1; 532 } 533 534 kn->kn_flags |= EV_CLEAR; /* automatically set */ 535 MALLOC(calloutp, callout_t *, sizeof(*calloutp), 536 M_KEVENT, 0); 537 callout_init(calloutp, 0); 538 callout_reset(calloutp, tticks, filt_timerexpire, kn); 539 kn->kn_hook = calloutp; 540 541 return (0); 542 } 543 544 static void 545 filt_timerdetach(struct knote *kn) 546 { 547 callout_t *calloutp; 548 549 calloutp = (callout_t *)kn->kn_hook; 550 callout_stop(calloutp); 551 callout_destroy(calloutp); 552 FREE(calloutp, M_KEVENT); 553 kq_ncallouts--; 554 } 555 556 static int 557 filt_timer(struct knote *kn, long hint) 558 { 559 return (kn->kn_data != 0); 560 } 561 562 /* 563 * filt_seltrue: 564 * 565 * This filter "event" routine simulates seltrue(). 566 */ 567 int 568 filt_seltrue(struct knote *kn, long hint) 569 { 570 571 /* 572 * We don't know how much data can be read/written, 573 * but we know that it *can* be. This is about as 574 * good as select/poll does as well. 575 */ 576 kn->kn_data = 0; 577 return (1); 578 } 579 580 /* 581 * This provides full kqfilter entry for device switch tables, which 582 * has same effect as filter using filt_seltrue() as filter method. 583 */ 584 static void 585 filt_seltruedetach(struct knote *kn) 586 { 587 /* Nothing to do */ 588 } 589 590 const struct filterops seltrue_filtops = 591 { 1, NULL, filt_seltruedetach, filt_seltrue }; 592 593 int 594 seltrue_kqfilter(dev_t dev, struct knote *kn) 595 { 596 switch (kn->kn_filter) { 597 case EVFILT_READ: 598 case EVFILT_WRITE: 599 kn->kn_fop = &seltrue_filtops; 600 break; 601 default: 602 return (EINVAL); 603 } 604 605 /* Nothing more to do */ 606 return (0); 607 } 608 609 /* 610 * kqueue(2) system call. 611 */ 612 int 613 sys_kqueue(struct lwp *l, const void *v, register_t *retval) 614 { 615 struct filedesc *fdp; 616 struct kqueue *kq; 617 struct file *fp; 618 int fd, error; 619 620 fdp = l->l_proc->p_fd; 621 error = falloc(l, &fp, &fd); /* setup a new file descriptor */ 622 if (error) 623 return (error); 624 fp->f_flag = FREAD | FWRITE; 625 fp->f_type = DTYPE_KQUEUE; 626 fp->f_ops = &kqueueops; 627 kq = pool_get(&kqueue_pool, PR_WAITOK); 628 memset((char *)kq, 0, sizeof(struct kqueue)); 629 simple_lock_init(&kq->kq_lock); 630 TAILQ_INIT(&kq->kq_head); 631 fp->f_data = (void *)kq; /* store the kqueue with the fp */ 632 *retval = fd; 633 if (fdp->fd_knlistsize < 0) 634 fdp->fd_knlistsize = 0; /* this process has a kq */ 635 kq->kq_fdp = fdp; 636 FILE_SET_MATURE(fp); 637 FILE_UNUSE(fp, l); /* falloc() does FILE_USE() */ 638 return (error); 639 } 640 641 /* 642 * kevent(2) system call. 643 */ 644 static int 645 kevent_fetch_changes(void *private, const struct kevent *changelist, 646 struct kevent *changes, size_t index, int n) 647 { 648 return copyin(changelist + index, changes, n * sizeof(*changes)); 649 } 650 651 static int 652 kevent_put_events(void *private, struct kevent *events, 653 struct kevent *eventlist, size_t index, int n) 654 { 655 return copyout(events, eventlist + index, n * sizeof(*events)); 656 } 657 658 static const struct kevent_ops kevent_native_ops = { 659 keo_private: NULL, 660 keo_fetch_timeout: copyin, 661 keo_fetch_changes: kevent_fetch_changes, 662 keo_put_events: kevent_put_events, 663 }; 664 665 int 666 sys_kevent(struct lwp *l, const struct sys_kevent_args *uap, register_t *retval) 667 { 668 /* { 669 syscallarg(int) fd; 670 syscallarg(const struct kevent *) changelist; 671 syscallarg(size_t) nchanges; 672 syscallarg(struct kevent *) eventlist; 673 syscallarg(size_t) nevents; 674 syscallarg(const struct timespec *) timeout; 675 } */ 676 677 return kevent1(l, retval, SCARG(uap, fd), SCARG(uap, changelist), 678 SCARG(uap, nchanges), SCARG(uap, eventlist), SCARG(uap, nevents), 679 SCARG(uap, timeout), &kevent_native_ops); 680 } 681 682 int 683 kevent1(struct lwp *l, register_t *retval, int fd, 684 const struct kevent *changelist, size_t nchanges, struct kevent *eventlist, 685 size_t nevents, const struct timespec *timeout, 686 const struct kevent_ops *keops) 687 { 688 struct kevent *kevp; 689 struct kqueue *kq; 690 struct file *fp; 691 struct timespec ts; 692 struct proc *p; 693 size_t i, n, ichange; 694 int nerrors, error; 695 696 p = l->l_proc; 697 /* check that we're dealing with a kq */ 698 fp = fd_getfile(p->p_fd, fd); 699 if (fp == NULL) 700 return (EBADF); 701 702 if (fp->f_type != DTYPE_KQUEUE) { 703 FILE_UNLOCK(fp); 704 return (EBADF); 705 } 706 707 FILE_USE(fp); 708 709 if (timeout != NULL) { 710 error = (*keops->keo_fetch_timeout)(timeout, &ts, sizeof(ts)); 711 if (error) 712 goto done; 713 timeout = &ts; 714 } 715 716 kq = (struct kqueue *)fp->f_data; 717 nerrors = 0; 718 ichange = 0; 719 720 /* traverse list of events to register */ 721 while (nchanges > 0) { 722 /* copyin a maximum of KQ_EVENTS at each pass */ 723 n = MIN(nchanges, KQ_NEVENTS); 724 error = (*keops->keo_fetch_changes)(keops->keo_private, 725 changelist, kq->kq_kev, ichange, n); 726 if (error) 727 goto done; 728 for (i = 0; i < n; i++) { 729 kevp = &kq->kq_kev[i]; 730 kevp->flags &= ~EV_SYSFLAGS; 731 /* register each knote */ 732 error = kqueue_register(kq, kevp, l); 733 if (error) { 734 if (nevents != 0) { 735 kevp->flags = EV_ERROR; 736 kevp->data = error; 737 error = (*keops->keo_put_events) 738 (keops->keo_private, kevp, 739 eventlist, nerrors, 1); 740 if (error) 741 goto done; 742 nevents--; 743 nerrors++; 744 } else { 745 goto done; 746 } 747 } 748 } 749 nchanges -= n; /* update the results */ 750 ichange += n; 751 } 752 if (nerrors) { 753 *retval = nerrors; 754 error = 0; 755 goto done; 756 } 757 758 /* actually scan through the events */ 759 error = kqueue_scan(fp, nevents, eventlist, timeout, l, retval, keops); 760 done: 761 FILE_UNUSE(fp, l); 762 return (error); 763 } 764 765 /* 766 * Register a given kevent kev onto the kqueue 767 */ 768 int 769 kqueue_register(struct kqueue *kq, struct kevent *kev, struct lwp *l) 770 { 771 const struct kfilter *kfilter; 772 struct filedesc *fdp; 773 struct file *fp; 774 struct knote *kn; 775 int s, error; 776 777 fdp = kq->kq_fdp; 778 fp = NULL; 779 kn = NULL; 780 error = 0; 781 kfilter = kfilter_byfilter(kev->filter); 782 if (kfilter == NULL || kfilter->filtops == NULL) { 783 /* filter not found nor implemented */ 784 return (EINVAL); 785 } 786 787 /* search if knote already exists */ 788 if (kfilter->filtops->f_isfd) { 789 /* monitoring a file descriptor */ 790 if ((fp = fd_getfile(fdp, kev->ident)) == NULL) 791 return (EBADF); /* validate descriptor */ 792 FILE_USE(fp); 793 794 if (kev->ident < fdp->fd_knlistsize) { 795 SLIST_FOREACH(kn, &fdp->fd_knlist[kev->ident], kn_link) 796 if (kq == kn->kn_kq && 797 kev->filter == kn->kn_filter) 798 break; 799 } 800 } else { 801 /* 802 * not monitoring a file descriptor, so 803 * lookup knotes in internal hash table 804 */ 805 if (fdp->fd_knhashmask != 0) { 806 struct klist *list; 807 808 list = &fdp->fd_knhash[ 809 KN_HASH((u_long)kev->ident, fdp->fd_knhashmask)]; 810 SLIST_FOREACH(kn, list, kn_link) 811 if (kev->ident == kn->kn_id && 812 kq == kn->kn_kq && 813 kev->filter == kn->kn_filter) 814 break; 815 } 816 } 817 818 if (kn == NULL && ((kev->flags & EV_ADD) == 0)) { 819 error = ENOENT; /* filter not found */ 820 goto done; 821 } 822 823 /* 824 * kn now contains the matching knote, or NULL if no match 825 */ 826 if (kev->flags & EV_ADD) { 827 /* add knote */ 828 829 if (kn == NULL) { 830 /* create new knote */ 831 kn = pool_get(&knote_pool, PR_WAITOK); 832 if (kn == NULL) { 833 error = ENOMEM; 834 goto done; 835 } 836 kn->kn_fp = fp; 837 kn->kn_kq = kq; 838 kn->kn_fop = kfilter->filtops; 839 840 /* 841 * apply reference count to knote structure, and 842 * do not release it at the end of this routine. 843 */ 844 fp = NULL; 845 846 kn->kn_sfflags = kev->fflags; 847 kn->kn_sdata = kev->data; 848 kev->fflags = 0; 849 kev->data = 0; 850 kn->kn_kevent = *kev; 851 852 knote_attach(kn, fdp); 853 if ((error = kfilter->filtops->f_attach(kn)) != 0) { 854 knote_drop(kn, l, fdp); 855 goto done; 856 } 857 } else { 858 /* modify existing knote */ 859 860 /* 861 * The user may change some filter values after the 862 * initial EV_ADD, but doing so will not reset any 863 * filter which have already been triggered. 864 */ 865 kn->kn_sfflags = kev->fflags; 866 kn->kn_sdata = kev->data; 867 kn->kn_kevent.udata = kev->udata; 868 } 869 870 s = splsched(); 871 if (kn->kn_fop->f_event(kn, 0)) 872 KNOTE_ACTIVATE(kn); 873 splx(s); 874 875 } else if (kev->flags & EV_DELETE) { /* delete knote */ 876 kn->kn_fop->f_detach(kn); 877 knote_drop(kn, l, fdp); 878 goto done; 879 } 880 881 /* disable knote */ 882 if ((kev->flags & EV_DISABLE) && 883 ((kn->kn_status & KN_DISABLED) == 0)) { 884 s = splsched(); 885 kn->kn_status |= KN_DISABLED; 886 splx(s); 887 } 888 889 /* enable knote */ 890 if ((kev->flags & EV_ENABLE) && (kn->kn_status & KN_DISABLED)) { 891 s = splsched(); 892 kn->kn_status &= ~KN_DISABLED; 893 if ((kn->kn_status & KN_ACTIVE) && 894 ((kn->kn_status & KN_QUEUED) == 0)) 895 knote_enqueue(kn); 896 splx(s); 897 } 898 899 done: 900 if (fp != NULL) 901 FILE_UNUSE(fp, l); 902 return (error); 903 } 904 905 /* 906 * Scan through the list of events on fp (for a maximum of maxevents), 907 * returning the results in to ulistp. Timeout is determined by tsp; if 908 * NULL, wait indefinitely, if 0 valued, perform a poll, otherwise wait 909 * as appropriate. 910 */ 911 static int 912 kqueue_scan(struct file *fp, size_t maxevents, struct kevent *ulistp, 913 const struct timespec *tsp, struct lwp *l, register_t *retval, 914 const struct kevent_ops *keops) 915 { 916 struct proc *p = l->l_proc; 917 struct kqueue *kq; 918 struct kevent *kevp; 919 struct timeval atv, sleeptv; 920 struct knote *kn, *marker=NULL; 921 size_t count, nkev, nevents; 922 int s, timeout, error; 923 924 kq = (struct kqueue *)fp->f_data; 925 count = maxevents; 926 nkev = nevents = error = 0; 927 if (count == 0) 928 goto done; 929 930 if (tsp) { /* timeout supplied */ 931 TIMESPEC_TO_TIMEVAL(&atv, tsp); 932 if (inittimeleft(&atv, &sleeptv) == -1) { 933 error = EINVAL; 934 goto done; 935 } 936 timeout = tvtohz(&atv); 937 if (timeout <= 0) 938 timeout = -1; /* do poll */ 939 } else { 940 /* no timeout, wait forever */ 941 timeout = 0; 942 } 943 944 MALLOC(marker, struct knote *, sizeof(*marker), M_KEVENT, M_WAITOK); 945 memset(marker, 0, sizeof(*marker)); 946 947 goto start; 948 949 retry: 950 if (tsp && (timeout = gettimeleft(&atv, &sleeptv)) <= 0) { 951 goto done; 952 } 953 954 start: 955 kevp = kq->kq_kev; 956 s = splsched(); 957 simple_lock(&kq->kq_lock); 958 if (kq->kq_count == 0) { 959 if (timeout < 0) { 960 error = EWOULDBLOCK; 961 simple_unlock(&kq->kq_lock); 962 } else { 963 kq->kq_state |= KQ_SLEEP; 964 error = ltsleep(kq, PSOCK | PCATCH | PNORELOCK, 965 "kqread", timeout, &kq->kq_lock); 966 } 967 splx(s); 968 if (error == 0) 969 goto retry; 970 /* don't restart after signals... */ 971 if (error == ERESTART) 972 error = EINTR; 973 else if (error == EWOULDBLOCK) 974 error = 0; 975 goto done; 976 } 977 978 /* mark end of knote list */ 979 TAILQ_INSERT_TAIL(&kq->kq_head, marker, kn_tqe); 980 simple_unlock(&kq->kq_lock); 981 982 while (count) { /* while user wants data ... */ 983 simple_lock(&kq->kq_lock); 984 kn = TAILQ_FIRST(&kq->kq_head); /* get next knote */ 985 TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe); 986 if (kn == marker) { /* if it's our marker, stop */ 987 /* What if it's some else's marker? */ 988 simple_unlock(&kq->kq_lock); 989 splx(s); 990 if (count == maxevents) 991 goto retry; 992 goto done; 993 } 994 kq->kq_count--; 995 simple_unlock(&kq->kq_lock); 996 997 if (kn->kn_status & KN_DISABLED) { 998 /* don't want disabled events */ 999 kn->kn_status &= ~KN_QUEUED; 1000 continue; 1001 } 1002 if ((kn->kn_flags & EV_ONESHOT) == 0 && 1003 kn->kn_fop->f_event(kn, 0) == 0) { 1004 /* 1005 * non-ONESHOT event that hasn't 1006 * triggered again, so de-queue. 1007 */ 1008 kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE); 1009 continue; 1010 } 1011 *kevp = kn->kn_kevent; 1012 kevp++; 1013 nkev++; 1014 if (kn->kn_flags & EV_ONESHOT) { 1015 /* delete ONESHOT events after retrieval */ 1016 kn->kn_status &= ~KN_QUEUED; 1017 splx(s); 1018 kn->kn_fop->f_detach(kn); 1019 knote_drop(kn, l, p->p_fd); 1020 s = splsched(); 1021 } else if (kn->kn_flags & EV_CLEAR) { 1022 /* clear state after retrieval */ 1023 kn->kn_data = 0; 1024 kn->kn_fflags = 0; 1025 kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE); 1026 } else { 1027 /* add event back on list */ 1028 simple_lock(&kq->kq_lock); 1029 TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe); 1030 kq->kq_count++; 1031 simple_unlock(&kq->kq_lock); 1032 } 1033 count--; 1034 if (nkev == KQ_NEVENTS) { 1035 /* do copyouts in KQ_NEVENTS chunks */ 1036 splx(s); 1037 error = (*keops->keo_put_events)(keops->keo_private, 1038 &kq->kq_kev[0], ulistp, nevents, nkev); 1039 nevents += nkev; 1040 nkev = 0; 1041 kevp = kq->kq_kev; 1042 s = splsched(); 1043 if (error) 1044 break; 1045 } 1046 } 1047 1048 /* remove marker */ 1049 simple_lock(&kq->kq_lock); 1050 TAILQ_REMOVE(&kq->kq_head, marker, kn_tqe); 1051 simple_unlock(&kq->kq_lock); 1052 splx(s); 1053 done: 1054 if (marker) 1055 FREE(marker, M_KEVENT); 1056 1057 if (nkev != 0) 1058 /* copyout remaining events */ 1059 error = (*keops->keo_put_events)(keops->keo_private, 1060 &kq->kq_kev[0], ulistp, nevents, nkev); 1061 *retval = maxevents - count; 1062 1063 return (error); 1064 } 1065 1066 /* 1067 * struct fileops read method for a kqueue descriptor. 1068 * Not implemented. 1069 * XXX: This could be expanded to call kqueue_scan, if desired. 1070 */ 1071 /*ARGSUSED*/ 1072 static int 1073 kqueue_read(struct file *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 1074 int flags) 1075 { 1076 1077 return (ENXIO); 1078 } 1079 1080 /* 1081 * struct fileops write method for a kqueue descriptor. 1082 * Not implemented. 1083 */ 1084 /*ARGSUSED*/ 1085 static int 1086 kqueue_write(struct file *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 1087 int flags) 1088 { 1089 1090 return (ENXIO); 1091 } 1092 1093 /* 1094 * struct fileops ioctl method for a kqueue descriptor. 1095 * 1096 * Two ioctls are currently supported. They both use struct kfilter_mapping: 1097 * KFILTER_BYNAME find name for filter, and return result in 1098 * name, which is of size len. 1099 * KFILTER_BYFILTER find filter for name. len is ignored. 1100 */ 1101 /*ARGSUSED*/ 1102 static int 1103 kqueue_ioctl(struct file *fp, u_long com, void *data, struct lwp *l) 1104 { 1105 struct kfilter_mapping *km; 1106 const struct kfilter *kfilter; 1107 char *name; 1108 int error; 1109 1110 km = (struct kfilter_mapping *)data; 1111 error = 0; 1112 1113 switch (com) { 1114 case KFILTER_BYFILTER: /* convert filter -> name */ 1115 kfilter = kfilter_byfilter(km->filter); 1116 if (kfilter != NULL) 1117 error = copyoutstr(kfilter->name, km->name, km->len, 1118 NULL); 1119 else 1120 error = ENOENT; 1121 break; 1122 1123 case KFILTER_BYNAME: /* convert name -> filter */ 1124 MALLOC(name, char *, KFILTER_MAXNAME, M_KEVENT, M_WAITOK); 1125 error = copyinstr(km->name, name, KFILTER_MAXNAME, NULL); 1126 if (error) { 1127 FREE(name, M_KEVENT); 1128 break; 1129 } 1130 kfilter = kfilter_byname(name); 1131 if (kfilter != NULL) 1132 km->filter = kfilter->filter; 1133 else 1134 error = ENOENT; 1135 FREE(name, M_KEVENT); 1136 break; 1137 1138 default: 1139 error = ENOTTY; 1140 1141 } 1142 return (error); 1143 } 1144 1145 /* 1146 * struct fileops fcntl method for a kqueue descriptor. 1147 * Not implemented. 1148 */ 1149 /*ARGSUSED*/ 1150 static int 1151 kqueue_fcntl(struct file *fp, u_int com, void *data, struct lwp *l) 1152 { 1153 1154 return (ENOTTY); 1155 } 1156 1157 /* 1158 * struct fileops poll method for a kqueue descriptor. 1159 * Determine if kqueue has events pending. 1160 */ 1161 static int 1162 kqueue_poll(struct file *fp, int events, struct lwp *l) 1163 { 1164 struct kqueue *kq; 1165 int revents; 1166 1167 kq = (struct kqueue *)fp->f_data; 1168 revents = 0; 1169 if (events & (POLLIN | POLLRDNORM)) { 1170 if (kq->kq_count) { 1171 revents |= events & (POLLIN | POLLRDNORM); 1172 } else { 1173 selrecord(l, &kq->kq_sel); 1174 } 1175 } 1176 return (revents); 1177 } 1178 1179 /* 1180 * struct fileops stat method for a kqueue descriptor. 1181 * Returns dummy info, with st_size being number of events pending. 1182 */ 1183 static int 1184 kqueue_stat(struct file *fp, struct stat *st, struct lwp *l) 1185 { 1186 struct kqueue *kq; 1187 1188 kq = (struct kqueue *)fp->f_data; 1189 memset((void *)st, 0, sizeof(*st)); 1190 st->st_size = kq->kq_count; 1191 st->st_blksize = sizeof(struct kevent); 1192 st->st_mode = S_IFIFO; 1193 return (0); 1194 } 1195 1196 /* 1197 * struct fileops close method for a kqueue descriptor. 1198 * Cleans up kqueue. 1199 */ 1200 static int 1201 kqueue_close(struct file *fp, struct lwp *l) 1202 { 1203 struct proc *p = l->l_proc; 1204 struct kqueue *kq; 1205 struct filedesc *fdp; 1206 struct knote **knp, *kn, *kn0; 1207 int i; 1208 1209 kq = (struct kqueue *)fp->f_data; 1210 fdp = p->p_fd; 1211 for (i = 0; i < fdp->fd_knlistsize; i++) { 1212 knp = &SLIST_FIRST(&fdp->fd_knlist[i]); 1213 kn = *knp; 1214 while (kn != NULL) { 1215 kn0 = SLIST_NEXT(kn, kn_link); 1216 if (kq == kn->kn_kq) { 1217 kn->kn_fop->f_detach(kn); 1218 FILE_UNUSE(kn->kn_fp, l); 1219 pool_put(&knote_pool, kn); 1220 *knp = kn0; 1221 } else { 1222 knp = &SLIST_NEXT(kn, kn_link); 1223 } 1224 kn = kn0; 1225 } 1226 } 1227 if (fdp->fd_knhashmask != 0) { 1228 for (i = 0; i < fdp->fd_knhashmask + 1; i++) { 1229 knp = &SLIST_FIRST(&fdp->fd_knhash[i]); 1230 kn = *knp; 1231 while (kn != NULL) { 1232 kn0 = SLIST_NEXT(kn, kn_link); 1233 if (kq == kn->kn_kq) { 1234 kn->kn_fop->f_detach(kn); 1235 /* XXX non-fd release of kn->kn_ptr */ 1236 pool_put(&knote_pool, kn); 1237 *knp = kn0; 1238 } else { 1239 knp = &SLIST_NEXT(kn, kn_link); 1240 } 1241 kn = kn0; 1242 } 1243 } 1244 } 1245 pool_put(&kqueue_pool, kq); 1246 fp->f_data = NULL; 1247 1248 return (0); 1249 } 1250 1251 /* 1252 * wakeup a kqueue 1253 */ 1254 static void 1255 kqueue_wakeup(struct kqueue *kq) 1256 { 1257 int s; 1258 1259 s = splsched(); 1260 simple_lock(&kq->kq_lock); 1261 if (kq->kq_state & KQ_SLEEP) { /* if currently sleeping ... */ 1262 kq->kq_state &= ~KQ_SLEEP; 1263 wakeup(kq); /* ... wakeup */ 1264 } 1265 1266 /* Notify select/poll and kevent. */ 1267 selnotify(&kq->kq_sel, 0); 1268 simple_unlock(&kq->kq_lock); 1269 splx(s); 1270 } 1271 1272 /* 1273 * struct fileops kqfilter method for a kqueue descriptor. 1274 * Event triggered when monitored kqueue changes. 1275 */ 1276 /*ARGSUSED*/ 1277 static int 1278 kqueue_kqfilter(struct file *fp, struct knote *kn) 1279 { 1280 struct kqueue *kq; 1281 1282 KASSERT(fp == kn->kn_fp); 1283 kq = (struct kqueue *)kn->kn_fp->f_data; 1284 if (kn->kn_filter != EVFILT_READ) 1285 return (1); 1286 kn->kn_fop = &kqread_filtops; 1287 SLIST_INSERT_HEAD(&kq->kq_sel.sel_klist, kn, kn_selnext); 1288 return (0); 1289 } 1290 1291 1292 /* 1293 * Walk down a list of knotes, activating them if their event has triggered. 1294 */ 1295 void 1296 knote(struct klist *list, long hint) 1297 { 1298 struct knote *kn; 1299 1300 SLIST_FOREACH(kn, list, kn_selnext) 1301 if (kn->kn_fop->f_event(kn, hint)) 1302 KNOTE_ACTIVATE(kn); 1303 } 1304 1305 /* 1306 * Remove all knotes from a specified klist 1307 */ 1308 void 1309 knote_remove(struct lwp *l, struct klist *list) 1310 { 1311 struct knote *kn; 1312 1313 while ((kn = SLIST_FIRST(list)) != NULL) { 1314 kn->kn_fop->f_detach(kn); 1315 knote_drop(kn, l, l->l_proc->p_fd); 1316 } 1317 } 1318 1319 /* 1320 * Remove all knotes referencing a specified fd 1321 */ 1322 void 1323 knote_fdclose(struct lwp *l, int fd) 1324 { 1325 struct filedesc *fdp; 1326 struct klist *list; 1327 1328 fdp = l->l_proc->p_fd; 1329 list = &fdp->fd_knlist[fd]; 1330 knote_remove(l, list); 1331 } 1332 1333 /* 1334 * Attach a new knote to a file descriptor 1335 */ 1336 static void 1337 knote_attach(struct knote *kn, struct filedesc *fdp) 1338 { 1339 struct klist *list; 1340 int size; 1341 1342 if (! kn->kn_fop->f_isfd) { 1343 /* if knote is not on an fd, store on internal hash table */ 1344 if (fdp->fd_knhashmask == 0) 1345 fdp->fd_knhash = hashinit(KN_HASHSIZE, HASH_LIST, 1346 M_KEVENT, M_WAITOK, &fdp->fd_knhashmask); 1347 list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)]; 1348 goto done; 1349 } 1350 1351 /* 1352 * otherwise, knote is on an fd. 1353 * knotes are stored in fd_knlist indexed by kn->kn_id. 1354 */ 1355 if (fdp->fd_knlistsize <= kn->kn_id) { 1356 /* expand list, it's too small */ 1357 size = fdp->fd_knlistsize; 1358 while (size <= kn->kn_id) { 1359 /* grow in KQ_EXTENT chunks */ 1360 size += KQ_EXTENT; 1361 } 1362 list = malloc(size * sizeof(struct klist *), M_KEVENT,M_WAITOK); 1363 if (fdp->fd_knlist) { 1364 /* copy existing knlist */ 1365 memcpy((void *)list, (void *)fdp->fd_knlist, 1366 fdp->fd_knlistsize * sizeof(struct klist *)); 1367 } 1368 /* 1369 * Zero new memory. Stylistically, SLIST_INIT() should be 1370 * used here, but that does same thing as the memset() anyway. 1371 */ 1372 memset(&list[fdp->fd_knlistsize], 0, 1373 (size - fdp->fd_knlistsize) * sizeof(struct klist *)); 1374 1375 /* switch to new knlist */ 1376 if (fdp->fd_knlist != NULL) 1377 free(fdp->fd_knlist, M_KEVENT); 1378 fdp->fd_knlistsize = size; 1379 fdp->fd_knlist = list; 1380 } 1381 1382 /* get list head for this fd */ 1383 list = &fdp->fd_knlist[kn->kn_id]; 1384 done: 1385 /* add new knote */ 1386 SLIST_INSERT_HEAD(list, kn, kn_link); 1387 kn->kn_status = 0; 1388 } 1389 1390 /* 1391 * Drop knote. 1392 * Should be called at spl == 0, since we don't want to hold spl 1393 * while calling FILE_UNUSE and free. 1394 */ 1395 static void 1396 knote_drop(struct knote *kn, struct lwp *l, struct filedesc *fdp) 1397 { 1398 struct klist *list; 1399 1400 if (kn->kn_fop->f_isfd) 1401 list = &fdp->fd_knlist[kn->kn_id]; 1402 else 1403 list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)]; 1404 1405 SLIST_REMOVE(list, kn, knote, kn_link); 1406 if (kn->kn_status & KN_QUEUED) 1407 knote_dequeue(kn); 1408 if (kn->kn_fop->f_isfd) 1409 FILE_UNUSE(kn->kn_fp, l); 1410 pool_put(&knote_pool, kn); 1411 } 1412 1413 1414 /* 1415 * Queue new event for knote. 1416 */ 1417 static void 1418 knote_enqueue(struct knote *kn) 1419 { 1420 struct kqueue *kq; 1421 int s; 1422 1423 kq = kn->kn_kq; 1424 KASSERT((kn->kn_status & KN_QUEUED) == 0); 1425 1426 s = splsched(); 1427 simple_lock(&kq->kq_lock); 1428 TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe); 1429 kn->kn_status |= KN_QUEUED; 1430 kq->kq_count++; 1431 simple_unlock(&kq->kq_lock); 1432 splx(s); 1433 kqueue_wakeup(kq); 1434 } 1435 1436 /* 1437 * Dequeue event for knote. 1438 */ 1439 static void 1440 knote_dequeue(struct knote *kn) 1441 { 1442 struct kqueue *kq; 1443 int s; 1444 1445 KASSERT(kn->kn_status & KN_QUEUED); 1446 kq = kn->kn_kq; 1447 1448 s = splsched(); 1449 simple_lock(&kq->kq_lock); 1450 TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe); 1451 kn->kn_status &= ~KN_QUEUED; 1452 kq->kq_count--; 1453 simple_unlock(&kq->kq_lock); 1454 splx(s); 1455 } 1456