27 */ 28 29#include <sys/param.h> 30#include <sys/systm.h> 31#include <sys/kernel.h> 32#include <sys/proc.h> 33#include <sys/malloc.h> 34#include <sys/unistd.h> 35#include <sys/file.h> 36#include <sys/fcntl.h> 37#include <sys/selinfo.h> 38#include <sys/queue.h> 39#include <sys/event.h> 40#include <sys/eventvar.h> 41#include <sys/poll.h> 42#include <sys/protosw.h> 43#include <sys/socket.h> 44#include <sys/socketvar.h> 45#include <sys/stat.h> 46#include <sys/sysproto.h> 47#include <sys/uio.h> 48 49#include <vm/vm_zone.h> 50 51static int filt_nullattach(struct knote *kn); 52static int filt_rwtypattach(struct knote *kn); 53static int filt_kqattach(struct knote *kn); 54static void filt_kqdetach(struct knote *kn); 55static int filt_kqueue(struct knote *kn, long hint); 56static int filt_procattach(struct knote *kn); 57static void filt_procdetach(struct knote *kn); 58static int filt_proc(struct knote *kn, long hint); 59 60static int kqueue_scan(struct file *fp, int maxevents, 61 struct kevent *ulistp, const struct timespec *timeout, 62 struct proc *p); 63static int kqueue_read(struct file *fp, struct uio *uio, 64 struct ucred *cred, int flags, struct proc *p); 65static int kqueue_write(struct file *fp, struct uio *uio, 66 struct ucred *cred, int flags, struct proc *p); 67static int kqueue_ioctl(struct file *fp, u_long com, caddr_t data, 68 struct proc *p); 69static int kqueue_poll(struct file *fp, int events, struct ucred *cred, 70 struct proc *p); 71static int kqueue_stat(struct file *fp, struct stat *st, struct proc *p); 72static int kqueue_close(struct file *fp, struct proc *p); 73static void kqueue_wakeup(struct kqueue *kq); 74 75static void knote_attach(struct knote *kn, struct filedesc *fdp); 76static void knote_drop(struct knote *kn, struct proc *p); 77static void knote_enqueue(struct knote *kn); 78static void knote_dequeue(struct knote *kn); 79static void knote_init(void); 80static struct knote *knote_alloc(void); 81static void knote_free(struct knote *kn); 82 83static vm_zone_t knote_zone; 84 85#define KNOTE_ACTIVATE(kn) do { \ 86 kn->kn_status |= KN_ACTIVE; \ 87 if ((kn->kn_status & (KN_QUEUED | KN_DISABLED)) == 0) \ 88 knote_enqueue(kn); \ 89} while(0) 90 91#define KN_HASHSIZE 64 /* XXX should be tunable */ 92#define KN_HASH(val, mask) (((val) ^ (val >> 8)) & (mask)) 93 94static struct fileops kqueueops = { 95 kqueue_read, 96 kqueue_write, 97 kqueue_ioctl, 98 kqueue_poll, 99 kqueue_stat, 100 kqueue_close 101}; 102 103extern struct filterops so_rwfiltops[]; 104extern struct filterops fifo_rwfiltops[]; 105extern struct filterops pipe_rwfiltops[]; 106extern struct filterops vn_rwfiltops[]; 107 108static struct filterops kq_rwfiltops[] = { 109 { 1, filt_kqattach, filt_kqdetach, filt_kqueue }, 110 { 1, filt_nullattach, NULL, NULL }, 111}; 112 113extern struct filterops aio_filtops; 114extern struct filterops sig_filtops; 115extern struct filterops vn_filtops; 116 117static struct filterops rwtype_filtops = 118 { 1, filt_rwtypattach, NULL, NULL }; 119static struct filterops proc_filtops = 120 { 0, filt_procattach, filt_procdetach, filt_proc }; 121 122/* 123 * XXX 124 * These must match the order of defines in <sys/file.h> 125 */ 126static struct filterops *rwtypfilt_sw[] = { 127 NULL, /* 0 */ 128 vn_rwfiltops, /* DTYPE_VNODE */ 129 so_rwfiltops, /* DTYPE_SOCKET */ 130 pipe_rwfiltops, /* DTYPE_PIPE */ 131 fifo_rwfiltops, /* DTYPE_FIFO */ 132 kq_rwfiltops, /* DTYPE_KQUEUE */ 133}; 134 135/* 136 * table for for all system-defined filters. 137 */ 138static struct filterops *sysfilt_ops[] = { 139 &rwtype_filtops, /* EVFILT_READ */ 140 &rwtype_filtops, /* EVFILT_WRITE */ 141 &aio_filtops, /* EVFILT_AIO */ 142 &vn_filtops, /* EVFILT_VNODE */ 143 &proc_filtops, /* EVFILT_PROC */ 144 &sig_filtops, /* EVFILT_SIGNAL */ 145}; 146 147static int 148filt_nullattach(struct knote *kn) 149{ 150 return (ENXIO); 151} 152 153/* 154 * file-type specific attach routine for read/write filters 155 */ 156static int 157filt_rwtypattach(struct knote *kn) 158{ 159 struct filterops *fops; 160 161 fops = rwtypfilt_sw[kn->kn_fp->f_type]; 162 if (fops == NULL) 163 return (EINVAL); 164 kn->kn_fop = &fops[~kn->kn_filter]; /* convert to 0-base index */ 165 return (kn->kn_fop->f_attach(kn)); 166} 167 168static int 169filt_kqattach(struct knote *kn) 170{ 171 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data; 172 173 SLIST_INSERT_HEAD(&kq->kq_sel.si_note, kn, kn_selnext); 174 return (0); 175} 176 177static void 178filt_kqdetach(struct knote *kn) 179{ 180 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data; 181 182 SLIST_REMOVE(&kq->kq_sel.si_note, kn, knote, kn_selnext); 183} 184 185/*ARGSUSED*/ 186static int 187filt_kqueue(struct knote *kn, long hint) 188{ 189 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data; 190 191 kn->kn_data = kq->kq_count; 192 return (kn->kn_data > 0); 193} 194 195static int 196filt_procattach(struct knote *kn) 197{ 198 struct proc *p; 199 200 p = pfind(kn->kn_id); 201 if (p == NULL) 202 return (ESRCH); 203 if (p_can(curproc, p, P_CAN_SEE, NULL)) 204 return (EACCES); 205 206 kn->kn_ptr.p_proc = p; 207 kn->kn_flags |= EV_CLEAR; /* automatically set */ 208 209 /* 210 * internal flag indicating registration done by kernel 211 */ 212 if (kn->kn_flags & EV_FLAG1) { 213 kn->kn_data = kn->kn_sdata; /* ppid */ 214 kn->kn_fflags = NOTE_CHILD; 215 kn->kn_flags &= ~EV_FLAG1; 216 } 217
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244} 245 246static int 247filt_proc(struct knote *kn, long hint) 248{ 249 u_int event; 250 251 /* 252 * mask off extra data 253 */ 254 event = (u_int)hint & NOTE_PCTRLMASK; 255 256 /* 257 * if the user is interested in this event, record it. 258 */ 259 if (kn->kn_sfflags & event) 260 kn->kn_fflags |= event; 261 262 /* 263 * process is gone, so flag the event as finished. 264 */ 265 if (event == NOTE_EXIT) { 266 kn->kn_status |= KN_DETACHED; 267 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 268 return (1); 269 } 270 271 /* 272 * process forked, and user wants to track the new process, 273 * so attach a new knote to it, and immediately report an 274 * event with the parent's pid. 275 */ 276 if ((event == NOTE_FORK) && (kn->kn_sfflags & NOTE_TRACK)) { 277 struct kevent kev; 278 int error; 279 280 /* 281 * register knote with new process. 282 */ 283 kev.ident = hint & NOTE_PDATAMASK; /* pid */ 284 kev.filter = kn->kn_filter; 285 kev.flags = kn->kn_flags | EV_ADD | EV_ENABLE | EV_FLAG1; 286 kev.fflags = kn->kn_sfflags; 287 kev.data = kn->kn_id; /* parent */ 288 kev.udata = kn->kn_kevent.udata; /* preserve udata */ 289 error = kqueue_register(kn->kn_kq, &kev, NULL); 290 if (error) 291 kn->kn_fflags |= NOTE_TRACKERR; 292 } 293 294 return (kn->kn_fflags != 0); 295} 296 297int 298kqueue(struct proc *p, struct kqueue_args *uap) 299{ 300 struct filedesc *fdp = p->p_fd; 301 struct kqueue *kq; 302 struct file *fp; 303 int fd, error; 304 305 error = falloc(p, &fp, &fd); 306 if (error) 307 return (error); 308 fp->f_flag = FREAD | FWRITE; 309 fp->f_type = DTYPE_KQUEUE; 310 fp->f_ops = &kqueueops; 311 kq = malloc(sizeof(struct kqueue), M_TEMP, M_WAITOK | M_ZERO); 312 TAILQ_INIT(&kq->kq_head); 313 fp->f_data = (caddr_t)kq; 314 p->p_retval[0] = fd; 315 if (fdp->fd_knlistsize < 0) 316 fdp->fd_knlistsize = 0; /* this process has a kq */ 317 kq->kq_fdp = fdp; 318 return (error); 319} 320 321#ifndef _SYS_SYSPROTO_H_ 322struct kevent_args { 323 int fd; 324 const struct kevent *changelist; 325 int nchanges; 326 struct kevent *eventlist; 327 int nevents; 328 const struct timespec *timeout; 329}; 330#endif 331int 332kevent(struct proc *p, struct kevent_args *uap) 333{ 334 struct filedesc* fdp = p->p_fd; 335 struct kevent *kevp; 336 struct kqueue *kq; 337 struct file *fp = NULL; 338 struct timespec ts; 339 int i, n, nerrors, error; 340 341 if (((u_int)uap->fd) >= fdp->fd_nfiles || 342 (fp = fdp->fd_ofiles[uap->fd]) == NULL || 343 (fp->f_type != DTYPE_KQUEUE)) 344 return (EBADF); 345 346 fhold(fp); 347 348 if (uap->timeout != NULL) { 349 error = copyin(uap->timeout, &ts, sizeof(ts)); 350 if (error) 351 goto done; 352 uap->timeout = &ts; 353 } 354 355 kq = (struct kqueue *)fp->f_data; 356 nerrors = 0; 357 358 while (uap->nchanges > 0) { 359 n = uap->nchanges > KQ_NEVENTS ? KQ_NEVENTS : uap->nchanges; 360 error = copyin(uap->changelist, kq->kq_kev, 361 n * sizeof(struct kevent)); 362 if (error) 363 goto done; 364 for (i = 0; i < n; i++) { 365 kevp = &kq->kq_kev[i]; 366 kevp->flags &= ~EV_SYSFLAGS; 367 error = kqueue_register(kq, kevp, p); 368 if (error) { 369 if (uap->nevents != 0) { 370 kevp->flags = EV_ERROR; 371 kevp->data = error; 372 (void) copyout((caddr_t)kevp, 373 (caddr_t)uap->eventlist, 374 sizeof(*kevp)); 375 uap->eventlist++; 376 uap->nevents--; 377 nerrors++; 378 } else { 379 goto done; 380 } 381 } 382 } 383 uap->nchanges -= n; 384 uap->changelist += n; 385 } 386 if (nerrors) { 387 p->p_retval[0] = nerrors; 388 error = 0; 389 goto done; 390 } 391 392 error = kqueue_scan(fp, uap->nevents, uap->eventlist, uap->timeout, p); 393done: 394 if (fp != NULL) 395 fdrop(fp, p); 396 return (error); 397} 398 399int 400kqueue_register(struct kqueue *kq, struct kevent *kev, struct proc *p) 401{ 402 struct filedesc *fdp = kq->kq_fdp; 403 struct filterops *fops; 404 struct file *fp = NULL; 405 struct knote *kn = NULL; 406 int s, error = 0; 407 408 if (kev->filter < 0) { 409 if (kev->filter + EVFILT_SYSCOUNT < 0) 410 return (EINVAL); 411 fops = sysfilt_ops[~kev->filter]; /* to 0-base index */ 412 } else { 413 /* 414 * XXX 415 * filter attach routine is responsible for insuring that 416 * the identifier can be attached to it. 417 */ 418 printf("unknown filter: %d\n", kev->filter); 419 return (EINVAL); 420 } 421 422 if (fops->f_isfd) { 423 /* validate descriptor */ 424 if ((u_int)kev->ident >= fdp->fd_nfiles || 425 (fp = fdp->fd_ofiles[kev->ident]) == NULL) 426 return (EBADF); 427 fhold(fp); 428 429 if (kev->ident < fdp->fd_knlistsize) { 430 SLIST_FOREACH(kn, &fdp->fd_knlist[kev->ident], kn_link) 431 if (kq == kn->kn_kq && 432 kev->filter == kn->kn_filter) 433 break; 434 } 435 } else { 436 if (fdp->fd_knhashmask != 0) { 437 struct klist *list; 438 439 list = &fdp->fd_knhash[ 440 KN_HASH((u_long)kev->ident, fdp->fd_knhashmask)]; 441 SLIST_FOREACH(kn, list, kn_link) 442 if (kev->ident == kn->kn_id && 443 kq == kn->kn_kq && 444 kev->filter == kn->kn_filter) 445 break; 446 } 447 } 448 449 if (kn == NULL && ((kev->flags & EV_ADD) == 0)) { 450 error = ENOENT; 451 goto done; 452 } 453 454 /* 455 * kn now contains the matching knote, or NULL if no match 456 */ 457 if (kev->flags & EV_ADD) { 458 459 if (kn == NULL) { 460 kn = knote_alloc(); 461 if (kn == NULL) { 462 error = ENOMEM; 463 goto done; 464 } 465 kn->kn_fp = fp; 466 kn->kn_kq = kq; 467 kn->kn_fop = fops; 468 469 /* 470 * apply reference count to knode structure, so 471 * do not release it at the end of this routine. 472 */ 473 fp = NULL; 474 475 kn->kn_sfflags = kev->fflags; 476 kn->kn_sdata = kev->data; 477 kev->fflags = 0; 478 kev->data = 0; 479 kn->kn_kevent = *kev; 480 481 knote_attach(kn, fdp); 482 if ((error = fops->f_attach(kn)) != 0) { 483 knote_drop(kn, p); 484 goto done; 485 } 486 } else { 487 /* 488 * The user may change some filter values after the 489 * initial EV_ADD, but doing so will not reset any 490 * filter which have already been triggered. 491 */ 492 kn->kn_sfflags = kev->fflags; 493 kn->kn_sdata = kev->data; 494 kn->kn_kevent.udata = kev->udata; 495 } 496 497 s = splhigh(); 498 if (kn->kn_fop->f_event(kn, 0)) 499 KNOTE_ACTIVATE(kn); 500 splx(s); 501 502 } else if (kev->flags & EV_DELETE) { 503 kn->kn_fop->f_detach(kn); 504 knote_drop(kn, p); 505 goto done; 506 } 507 508 if ((kev->flags & EV_DISABLE) && 509 ((kn->kn_status & KN_DISABLED) == 0)) { 510 s = splhigh(); 511 kn->kn_status |= KN_DISABLED; 512 splx(s); 513 } 514 515 if ((kev->flags & EV_ENABLE) && (kn->kn_status & KN_DISABLED)) { 516 s = splhigh(); 517 kn->kn_status &= ~KN_DISABLED; 518 if ((kn->kn_status & KN_ACTIVE) && 519 ((kn->kn_status & KN_QUEUED) == 0)) 520 knote_enqueue(kn); 521 splx(s); 522 } 523 524done: 525 if (fp != NULL) 526 fdrop(fp, p); 527 return (error); 528} 529 530static int 531kqueue_scan(struct file *fp, int maxevents, struct kevent *ulistp, 532 const struct timespec *tsp, struct proc *p) 533{ 534 struct kqueue *kq = (struct kqueue *)fp->f_data; 535 struct kevent *kevp; 536 struct timeval atv, rtv, ttv; 537 struct knote *kn, marker; 538 int s, count, timeout, nkev = 0, error = 0; 539 540 count = maxevents; 541 if (count == 0) 542 goto done; 543 544 if (tsp != NULL) { 545 TIMESPEC_TO_TIMEVAL(&atv, tsp); 546 if (itimerfix(&atv)) { 547 error = EINVAL; 548 goto done; 549 } 550 if (tsp->tv_sec == 0 && tsp->tv_nsec == 0) 551 timeout = -1; 552 else 553 timeout = atv.tv_sec > 24 * 60 * 60 ? 554 24 * 60 * 60 * hz : tvtohz(&atv); 555 getmicrouptime(&rtv); 556 timevaladd(&atv, &rtv); 557 } else { 558 atv.tv_sec = 0; 559 atv.tv_usec = 0; 560 timeout = 0; 561 } 562 goto start; 563 564retry: 565 if (atv.tv_sec || atv.tv_usec) { 566 getmicrouptime(&rtv); 567 if (timevalcmp(&rtv, &atv, >=)) 568 goto done; 569 ttv = atv; 570 timevalsub(&ttv, &rtv); 571 timeout = ttv.tv_sec > 24 * 60 * 60 ? 572 24 * 60 * 60 * hz : tvtohz(&ttv); 573 } 574 575start: 576 kevp = kq->kq_kev; 577 s = splhigh(); 578 if (kq->kq_count == 0) { 579 if (timeout < 0) { 580 error = EWOULDBLOCK; 581 } else { 582 kq->kq_state |= KQ_SLEEP; 583 error = tsleep(kq, PSOCK | PCATCH, "kqread", timeout); 584 } 585 splx(s); 586 if (error == 0) 587 goto retry; 588 /* don't restart after signals... */ 589 if (error == ERESTART) 590 error = EINTR; 591 else if (error == EWOULDBLOCK) 592 error = 0; 593 goto done; 594 } 595 596 TAILQ_INSERT_TAIL(&kq->kq_head, &marker, kn_tqe); 597 while (count) { 598 kn = TAILQ_FIRST(&kq->kq_head); 599 TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe); 600 if (kn == &marker) { 601 splx(s); 602 if (count == maxevents) 603 goto retry; 604 goto done; 605 } 606 if (kn->kn_status & KN_DISABLED) { 607 kn->kn_status &= ~KN_QUEUED; 608 kq->kq_count--; 609 continue; 610 } 611 if ((kn->kn_flags & EV_ONESHOT) == 0 && 612 kn->kn_fop->f_event(kn, 0) == 0) { 613 kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE); 614 kq->kq_count--; 615 continue; 616 } 617 *kevp = kn->kn_kevent; 618 kevp++; 619 nkev++; 620 if (kn->kn_flags & EV_ONESHOT) { 621 kn->kn_status &= ~KN_QUEUED; 622 kq->kq_count--; 623 splx(s); 624 kn->kn_fop->f_detach(kn); 625 knote_drop(kn, p); 626 s = splhigh(); 627 } else if (kn->kn_flags & EV_CLEAR) { 628 kn->kn_data = 0; 629 kn->kn_fflags = 0; 630 kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE); 631 kq->kq_count--; 632 } else { 633 TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe); 634 } 635 count--; 636 if (nkev == KQ_NEVENTS) { 637 splx(s); 638 error = copyout((caddr_t)&kq->kq_kev, (caddr_t)ulistp, 639 sizeof(struct kevent) * nkev); 640 ulistp += nkev; 641 nkev = 0; 642 kevp = kq->kq_kev; 643 s = splhigh(); 644 if (error) 645 break; 646 } 647 } 648 TAILQ_REMOVE(&kq->kq_head, &marker, kn_tqe); 649 splx(s); 650done: 651 if (nkev != 0) 652 error = copyout((caddr_t)&kq->kq_kev, (caddr_t)ulistp, 653 sizeof(struct kevent) * nkev); 654 p->p_retval[0] = maxevents - count; 655 return (error); 656} 657 658/* 659 * XXX 660 * This could be expanded to call kqueue_scan, if desired. 661 */ 662/*ARGSUSED*/ 663static int 664kqueue_read(struct file *fp, struct uio *uio, struct ucred *cred, 665 int flags, struct proc *p) 666{ 667 return (ENXIO); 668} 669 670/*ARGSUSED*/ 671static int 672kqueue_write(struct file *fp, struct uio *uio, struct ucred *cred, 673 int flags, struct proc *p) 674{ 675 return (ENXIO); 676} 677 678/*ARGSUSED*/ 679static int 680kqueue_ioctl(struct file *fp, u_long com, caddr_t data, struct proc *p) 681{ 682 return (ENOTTY); 683} 684 685/*ARGSUSED*/ 686static int 687kqueue_poll(struct file *fp, int events, struct ucred *cred, struct proc *p) 688{ 689 struct kqueue *kq = (struct kqueue *)fp->f_data; 690 int revents = 0; 691 int s = splnet(); 692 693 if (events & (POLLIN | POLLRDNORM)) { 694 if (kq->kq_count) { 695 revents |= events & (POLLIN | POLLRDNORM); 696 } else { 697 selrecord(p, &kq->kq_sel); 698 kq->kq_state |= KQ_SEL; 699 } 700 } 701 splx(s); 702 return (revents); 703} 704 705/*ARGSUSED*/ 706static int 707kqueue_stat(struct file *fp, struct stat *st, struct proc *p) 708{ 709 struct kqueue *kq = (struct kqueue *)fp->f_data; 710 711 bzero((void *)st, sizeof(*st)); 712 st->st_size = kq->kq_count; 713 st->st_blksize = sizeof(struct kevent); 714 st->st_mode = S_IFIFO; 715 return (0); 716} 717 718/*ARGSUSED*/ 719static int 720kqueue_close(struct file *fp, struct proc *p) 721{ 722 struct kqueue *kq = (struct kqueue *)fp->f_data; 723 struct filedesc *fdp = p->p_fd; 724 struct knote **knp, *kn, *kn0; 725 int i; 726 727 for (i = 0; i < fdp->fd_knlistsize; i++) { 728 knp = &SLIST_FIRST(&fdp->fd_knlist[i]); 729 kn = *knp; 730 while (kn != NULL) { 731 kn0 = SLIST_NEXT(kn, kn_link); 732 if (kq == kn->kn_kq) { 733 kn->kn_fop->f_detach(kn); 734 fdrop(kn->kn_fp, p); 735 knote_free(kn); 736 *knp = kn0; 737 } else { 738 knp = &SLIST_NEXT(kn, kn_link); 739 } 740 kn = kn0; 741 } 742 } 743 if (fdp->fd_knhashmask != 0) { 744 for (i = 0; i < fdp->fd_knhashmask + 1; i++) { 745 knp = &SLIST_FIRST(&fdp->fd_knhash[i]); 746 kn = *knp; 747 while (kn != NULL) { 748 kn0 = SLIST_NEXT(kn, kn_link); 749 if (kq == kn->kn_kq) { 750 kn->kn_fop->f_detach(kn); 751 /* XXX non-fd release of kn->kn_ptr */ 752 knote_free(kn); 753 *knp = kn0; 754 } else { 755 knp = &SLIST_NEXT(kn, kn_link); 756 } 757 kn = kn0; 758 } 759 } 760 } 761 free(kq, M_TEMP); 762 fp->f_data = NULL; 763 764 return (0); 765} 766 767static void 768kqueue_wakeup(struct kqueue *kq) 769{ 770 771 if (kq->kq_state & KQ_SLEEP) { 772 kq->kq_state &= ~KQ_SLEEP; 773 wakeup(kq); 774 } 775 if (kq->kq_state & KQ_SEL) { 776 kq->kq_state &= ~KQ_SEL; 777 selwakeup(&kq->kq_sel); 778 } 779 KNOTE(&kq->kq_sel.si_note, 0); 780} 781 782/* 783 * walk down a list of knotes, activating them if their event has triggered. 784 */ 785void 786knote(struct klist *list, long hint) 787{ 788 struct knote *kn; 789 790 SLIST_FOREACH(kn, list, kn_selnext) 791 if (kn->kn_fop->f_event(kn, hint)) 792 KNOTE_ACTIVATE(kn); 793} 794 795/* 796 * remove all knotes from a specified klist 797 */ 798void 799knote_remove(struct proc *p, struct klist *list) 800{ 801 struct knote *kn; 802 803 while ((kn = SLIST_FIRST(list)) != NULL) { 804 kn->kn_fop->f_detach(kn); 805 knote_drop(kn, p); 806 } 807} 808 809/* 810 * remove all knotes referencing a specified fd 811 */ 812void 813knote_fdclose(struct proc *p, int fd) 814{ 815 struct filedesc *fdp = p->p_fd; 816 struct klist *list = &fdp->fd_knlist[fd]; 817 818 knote_remove(p, list); 819} 820 821static void 822knote_attach(struct knote *kn, struct filedesc *fdp) 823{ 824 struct klist *list; 825 int size; 826 827 if (! kn->kn_fop->f_isfd) { 828 if (fdp->fd_knhashmask == 0) 829 fdp->fd_knhash = hashinit(KN_HASHSIZE, M_TEMP, 830 &fdp->fd_knhashmask); 831 list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)]; 832 goto done; 833 } 834 835 if (fdp->fd_knlistsize <= kn->kn_id) { 836 size = fdp->fd_knlistsize; 837 while (size <= kn->kn_id) 838 size += KQEXTENT; 839 MALLOC(list, struct klist *, 840 size * sizeof(struct klist *), M_TEMP, M_WAITOK); 841 bcopy((caddr_t)fdp->fd_knlist, (caddr_t)list, 842 fdp->fd_knlistsize * sizeof(struct klist *)); 843 bzero((caddr_t)list + 844 fdp->fd_knlistsize * sizeof(struct klist *), 845 (size - fdp->fd_knlistsize) * sizeof(struct klist *)); 846 if (fdp->fd_knlist != NULL) 847 FREE(fdp->fd_knlist, M_TEMP); 848 fdp->fd_knlistsize = size; 849 fdp->fd_knlist = list; 850 } 851 list = &fdp->fd_knlist[kn->kn_id]; 852done: 853 SLIST_INSERT_HEAD(list, kn, kn_link); 854 kn->kn_status = 0; 855} 856 857/* 858 * should be called at spl == 0, since we don't want to hold spl 859 * while calling fdrop and free. 860 */ 861static void 862knote_drop(struct knote *kn, struct proc *p) 863{ 864 struct filedesc *fdp = p->p_fd; 865 struct klist *list; 866 867 if (kn->kn_fop->f_isfd) 868 list = &fdp->fd_knlist[kn->kn_id]; 869 else 870 list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)]; 871 872 SLIST_REMOVE(list, kn, knote, kn_link); 873 if (kn->kn_status & KN_QUEUED) 874 knote_dequeue(kn); 875 if (kn->kn_fop->f_isfd) 876 fdrop(kn->kn_fp, p); 877 knote_free(kn); 878} 879 880 881static void 882knote_enqueue(struct knote *kn) 883{ 884 struct kqueue *kq = kn->kn_kq; 885 int s = splhigh(); 886 887 KASSERT((kn->kn_status & KN_QUEUED) == 0, ("knote already queued")); 888 889 TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe); 890 kn->kn_status |= KN_QUEUED; 891 kq->kq_count++; 892 splx(s); 893 kqueue_wakeup(kq); 894} 895 896static void 897knote_dequeue(struct knote *kn) 898{ 899 struct kqueue *kq = kn->kn_kq; 900 int s = splhigh(); 901 902 KASSERT(kn->kn_status & KN_QUEUED, ("knote not queued")); 903 904 TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe); 905 kn->kn_status &= ~KN_QUEUED; 906 kq->kq_count--; 907 splx(s); 908} 909 910static void 911knote_init(void) 912{ 913 knote_zone = zinit("KNOTE", sizeof(struct knote), 0, 0, 1); 914} 915SYSINIT(knote, SI_SUB_PSEUDO, SI_ORDER_ANY, knote_init, NULL) 916 917static struct knote * 918knote_alloc(void) 919{ 920 return ((struct knote *)zalloc(knote_zone)); 921} 922 923static void 924knote_free(struct knote *kn) 925{ 926 zfree(knote_zone, kn); 927}
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