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authorjlemon <jlemon@FreeBSD.org>2000-04-16 19:02:08 +0000
committerjlemon <jlemon@FreeBSD.org>2000-04-16 19:02:08 +0000
commitd85bc582cfae02f27415b84f966c1a8f0dede93b (patch)
tree96188fc178e1095bbf542a066e2f2581027067af /sys/kern/kern_event.c
parent42f19b906955a4b3ed85af73d1008731a67d8ffc (diff)
downloadFreeBSD-src-d85bc582cfae02f27415b84f966c1a8f0dede93b.zip
FreeBSD-src-d85bc582cfae02f27415b84f966c1a8f0dede93b.tar.gz
Add files that I forgot to `cvs add' on last commit.
Diffstat (limited to 'sys/kern/kern_event.c')
-rw-r--r--sys/kern/kern_event.c907
1 files changed, 907 insertions, 0 deletions
diff --git a/sys/kern/kern_event.c b/sys/kern/kern_event.c
new file mode 100644
index 0000000..f044165
--- /dev/null
+++ b/sys/kern/kern_event.c
@@ -0,0 +1,907 @@
+/*-
+ * Copyright (c) 1999,2000 Jonathan Lemon <jlemon@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/proc.h>
+#include <sys/malloc.h>
+#include <sys/unistd.h>
+#include <sys/file.h>
+#include <sys/fcntl.h>
+#include <sys/select.h>
+#include <sys/queue.h>
+#include <sys/event.h>
+#include <sys/eventvar.h>
+#include <sys/poll.h>
+#include <sys/protosw.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/stat.h>
+#include <sys/sysproto.h>
+#include <sys/uio.h>
+
+#include <vm/vm_zone.h>
+
+static int filt_nullattach(struct knote *kn);
+static int filt_rwtypattach(struct knote *kn);
+static int filt_kqattach(struct knote *kn);
+static void filt_kqdetach(struct knote *kn);
+static int filt_kqueue(struct knote *kn, long hint);
+static int filt_procattach(struct knote *kn);
+static void filt_procdetach(struct knote *kn);
+static int filt_proc(struct knote *kn, long hint);
+
+static int kqueue_create(struct kqueue **kqp);
+static int kqueue_scan(struct file *fp, int maxevents,
+ struct kevent *ulistp, struct timespec *timeout,
+ struct proc *p);
+static int kqueue_read(struct file *fp, struct uio *uio,
+ struct ucred *cred, int flags, struct proc *p);
+static int kqueue_write(struct file *fp, struct uio *uio,
+ struct ucred *cred, int flags, struct proc *p);
+static int kqueue_ioctl(struct file *fp, u_long com, caddr_t data,
+ struct proc *p);
+static int kqueue_poll(struct file *fp, int events, struct ucred *cred,
+ struct proc *p);
+static int kqueue_stat(struct file *fp, struct stat *st, struct proc *p);
+static int kqueue_close(struct file *fp, struct proc *p);
+static void kqueue_wakeup(struct kqueue *kq);
+
+static void knote_attach(struct knote *kn, struct filedesc *fdp);
+static void knote_drop(struct knote *kn, struct proc *p);
+static void knote_enqueue(struct knote *kn);
+static void knote_dequeue(struct knote *kn);
+static void knote_init(void);
+static struct knote *knote_alloc(void);
+static void knote_free(struct knote *kn);
+
+static vm_zone_t knote_zone;
+
+#define KNOTE_ACTIVATE(kn) do { \
+ kn->kn_status |= KN_ACTIVE; \
+ if ((kn->kn_status & (KN_QUEUED | KN_DISABLED)) == 0) \
+ knote_enqueue(kn); \
+} while(0)
+
+#define KN_HASHSIZE 64 /* XXX should be tunable */
+#define KN_HASH(val, mask) (((val) ^ (val >> 8)) & (mask))
+
+static struct fileops kqueueops = {
+ kqueue_read,
+ kqueue_write,
+ kqueue_ioctl,
+ kqueue_poll,
+ kqueue_stat,
+ kqueue_close
+};
+
+extern struct filterops so_rwfiltops[];
+extern struct filterops fifo_rwfiltops[];
+extern struct filterops pipe_rwfiltops[];
+extern struct filterops vn_rwfiltops[];
+
+static struct filterops kq_rwfiltops[] = {
+ { 1, filt_kqattach, filt_kqdetach, filt_kqueue },
+ { 1, filt_nullattach, NULL, NULL },
+};
+
+extern struct filterops aio_filtops;
+extern struct filterops sig_filtops;
+extern struct filterops vn_filtops;
+
+static struct filterops rwtype_filtops =
+ { 1, filt_rwtypattach, NULL, NULL };
+static struct filterops proc_filtops =
+ { 0, filt_procattach, filt_procdetach, filt_proc };
+
+/*
+ * XXX
+ * These must match the order of defines in <sys/file.h>
+ */
+static struct filterops *rwtypfilt_sw[] = {
+ NULL, /* 0 */
+ vn_rwfiltops, /* DTYPE_VNODE */
+ so_rwfiltops, /* DTYPE_SOCKET */
+ pipe_rwfiltops, /* DTYPE_PIPE */
+ fifo_rwfiltops, /* DTYPE_FIFO */
+ kq_rwfiltops, /* DTYPE_KQUEUE */
+};
+
+/*
+ * table for for all system-defined filters.
+ */
+static struct filterops *sysfilt_ops[] = {
+ &rwtype_filtops, /* EVFILT_READ */
+ &rwtype_filtops, /* EVFILT_WRITE */
+ &aio_filtops, /* EVFILT_AIO */
+ &vn_filtops, /* EVFILT_VNODE */
+ &proc_filtops, /* EVFILT_PROC */
+ &sig_filtops, /* EVFILT_SIGNAL */
+};
+
+static int
+filt_nullattach(struct knote *kn)
+{
+ return (ENXIO);
+}
+
+/*
+ * file-type specific attach routine for read/write filters
+ */
+static int
+filt_rwtypattach(struct knote *kn)
+{
+ struct filterops *fops;
+
+ fops = rwtypfilt_sw[kn->kn_fp->f_type];
+ if (fops == NULL)
+ return (EINVAL);
+ kn->kn_fop = &fops[~kn->kn_filter]; /* convert to 0-base index */
+ return (kn->kn_fop->f_attach(kn));
+}
+
+static int
+filt_kqattach(struct knote *kn)
+{
+ struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
+
+ SLIST_INSERT_HEAD(&kq->kq_sel.si_note, kn, kn_selnext);
+ return (0);
+}
+
+static void
+filt_kqdetach(struct knote *kn)
+{
+ struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
+
+ SLIST_REMOVE(&kq->kq_sel.si_note, kn, knote, kn_selnext);
+}
+
+/*ARGSUSED*/
+static int
+filt_kqueue(struct knote *kn, long hint)
+{
+ struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
+
+ kn->kn_data = kq->kq_count;
+ return (kn->kn_data > 0);
+}
+
+static int
+filt_procattach(struct knote *kn)
+{
+ struct proc *p;
+
+ p = pfind(kn->kn_id);
+ if (p == NULL)
+ return (ESRCH);
+ if (! PRISON_CHECK(curproc, p))
+ return (EACCES);
+
+ kn->kn_ptr.p_proc = p;
+ kn->kn_flags |= EV_CLEAR; /* automatically set */
+
+ /*
+ * internal flag indicating registration done by kernel
+ */
+ if (kn->kn_flags & EV_FLAG1) {
+ kn->kn_data = kn->kn_sdata; /* ppid */
+ kn->kn_fflags = NOTE_CHILD;
+ kn->kn_flags &= ~EV_FLAG1;
+ }
+
+ /* XXX lock the proc here while adding to the list? */
+ SLIST_INSERT_HEAD(&p->p_klist, kn, kn_selnext);
+
+ return (0);
+}
+
+/*
+ * The knote may be attached to a different process, which may exit,
+ * leaving nothing for the knote to be attached to. So when the process
+ * exits, the knote is marked as DETACHED and also flagged as ONESHOT so
+ * it will be deleted when read out. However, as part of the knote deletion,
+ * this routine is called, so a check is needed to avoid actually performing
+ * a detach, because the original process does not exist any more.
+ */
+static void
+filt_procdetach(struct knote *kn)
+{
+ struct proc *p = kn->kn_ptr.p_proc;
+
+ if (kn->kn_status & KN_DETACHED)
+ return;
+
+ /* XXX locking? this might modify another process. */
+ SLIST_REMOVE(&p->p_klist, kn, knote, kn_selnext);
+}
+
+static int
+filt_proc(struct knote *kn, long hint)
+{
+ u_int event;
+
+ /*
+ * mask off extra data
+ */
+ event = (u_int)hint & NOTE_PCTRLMASK;
+
+ /*
+ * if the user is interested in this event, record it.
+ */
+ if (kn->kn_sfflags & event)
+ kn->kn_fflags |= event;
+
+ /*
+ * process is gone, so flag the event as finished.
+ */
+ if (event == NOTE_EXIT) {
+ kn->kn_status |= KN_DETACHED;
+ kn->kn_flags |= (EV_EOF | EV_ONESHOT);
+ return (1);
+ }
+
+ /*
+ * process forked, and user wants to track the new process,
+ * so attach a new knote to it, and immediately report an
+ * event with the parent's pid.
+ */
+ if ((event == NOTE_FORK) && (kn->kn_sfflags & NOTE_TRACK)) {
+ struct kevent kev;
+ int error;
+
+ /*
+ * register knote with new process.
+ */
+ kev.ident = hint & NOTE_PDATAMASK; /* pid */
+ kev.filter = kn->kn_filter;
+ kev.flags = kn->kn_flags | EV_ADD | EV_ENABLE | EV_FLAG1;
+ kev.fflags = kn->kn_sfflags;
+ kev.data = kn->kn_id; /* parent */
+ error = kqueue_register(kn->kn_kq, &kev, NULL);
+ if (error)
+ kn->kn_fflags |= NOTE_TRACKERR;
+ }
+
+ return (kn->kn_fflags != 0);
+}
+
+static int
+kqueue_create(struct kqueue **kqp)
+{
+ struct kqueue *kq;
+
+ kq = malloc(sizeof(struct kqueue), M_TEMP, M_WAITOK);
+ if (kq == NULL)
+ return (EAGAIN);
+ bzero(kq, sizeof(*kq));
+ TAILQ_INIT(&kq->kq_head);
+
+ *kqp = kq;
+ return (0);
+}
+
+int
+kqueue(struct proc *p, struct kqueue_args *uap)
+{
+ struct filedesc *fdp = p->p_fd;
+ struct kqueue *kq;
+ struct file *fp;
+ int fd, error;
+
+ error = falloc(p, &fp, &fd);
+ if (error)
+ return (error);
+ fp->f_flag = FREAD | FWRITE;
+ fp->f_type = DTYPE_KQUEUE;
+ fp->f_ops = &kqueueops;
+ error = kqueue_create(&kq);
+ if (error) {
+ fdp->fd_ofiles[fd] = 0;
+ ffree(fp);
+ } else {
+ fp->f_data = (caddr_t)kq;
+ p->p_retval[0] = fd;
+ }
+ fdp->fd_knlistsize = 0; /* mark this fdesc as having a kq */
+ kq->kq_fdp = fdp;
+ return (error);
+}
+
+#ifndef _SYS_SYSPROTO_H_
+struct kevent_args {
+ int fd;
+ int nchanges;
+ struct kevent **changelist;
+ int nevents;
+ struct kevent *eventlist;
+ struct timespec *timeout;
+};
+#endif
+int
+kevent(struct proc *p, struct kevent_args *uap)
+{
+ struct filedesc* fdp = p->p_fd;
+ struct kevent kev;
+ struct kqueue *kq;
+ struct file *fp;
+ struct timespec ts;
+ int i, n, nerrors, error;
+
+ if (((u_int)uap->fd) >= fdp->fd_nfiles ||
+ (fp = fdp->fd_ofiles[uap->fd]) == NULL ||
+ (fp->f_type != DTYPE_KQUEUE))
+ return (EBADF);
+
+ if (uap->timeout != NULL) {
+ error = copyin((caddr_t)uap->timeout, (caddr_t)&ts,
+ sizeof(ts));
+ if (error)
+ return error;
+ uap->timeout = &ts;
+ }
+
+ kq = (struct kqueue *)fp->f_data;
+ nerrors = 0;
+
+ while (uap->nchanges > 0) {
+ n = uap->nchanges > KQ_NEVENTS ? KQ_NEVENTS : uap->nchanges;
+ error = copyin((caddr_t)uap->changelist, (caddr_t)kq->kq_kevp,
+ n * sizeof(struct kevent *));
+ if (error)
+ return (error);
+ for (i = 0; i < n; i++) {
+ error = copyin((caddr_t)kq->kq_kevp[i],
+ (caddr_t)&kev, sizeof(kev));
+ if (error)
+ return (error);
+ kev.flags &= ~EV_SYSFLAGS;
+ error = kqueue_register(kq, &kev, p);
+ if (error) {
+ if (uap->nevents != 0) {
+ kev.flags = EV_ERROR;
+ kev.data = error;
+ (void) copyout((caddr_t)&kev,
+ (caddr_t)uap->eventlist,
+ sizeof(kev));
+ uap->eventlist++;
+ uap->nevents--;
+ nerrors++;
+ } else {
+ return (error);
+ }
+ }
+ }
+ uap->nchanges -= n;
+ uap->changelist += n;
+ }
+ if (nerrors) {
+ p->p_retval[0] = nerrors;
+ return (0);
+ }
+
+ error = kqueue_scan(fp, uap->nevents, uap->eventlist, uap->timeout, p);
+ return (error);
+}
+
+int
+kqueue_register(struct kqueue *kq, struct kevent *kev, struct proc *p)
+{
+ struct filedesc *fdp = kq->kq_fdp;
+ struct filterops *fops;
+ struct file *fp = NULL;
+ struct knote *kn = NULL;
+ int s, error = 0;
+
+ if (kev->filter < 0) {
+ if (kev->filter + EVFILT_SYSCOUNT < 0)
+ return (EINVAL);
+ fops = sysfilt_ops[~kev->filter]; /* to 0-base index */
+ } else {
+ /*
+ * XXX
+ * filter attach routine is responsible for insuring that
+ * the identifier can be attached to it.
+ */
+ printf("unknown filter: %d\n", kev->filter);
+ return (EINVAL);
+ }
+
+ if (fops->f_isfd) {
+ /* validate descriptor; ignore invalid descriptors */
+ if ((u_int)kev->ident >= fdp->fd_nfiles ||
+ (fp = fdp->fd_ofiles[kev->ident]) == NULL)
+ return (0);
+
+ if (kev->ident < fdp->fd_knlistsize) {
+ SLIST_FOREACH(kn, &fdp->fd_knlist[kev->ident], kn_link)
+ if (kq == kn->kn_kq &&
+ kev->filter == kn->kn_filter)
+ break;
+ }
+ } else {
+ if (fdp->fd_knhashmask != 0) {
+ struct klist *list;
+
+ list = &fdp->fd_knhash[
+ KN_HASH((u_long)kev->ident, fdp->fd_knhashmask)];
+ SLIST_FOREACH(kn, list, kn_link)
+ if (kev->ident == kn->kn_id &&
+ kq == kn->kn_kq &&
+ kev->filter == kn->kn_filter)
+ break;
+ }
+ }
+
+ if (kn == NULL && ((kev->flags & EV_ADD) == 0))
+ goto done;
+
+ /*
+ * kn now contains the matching knote, or NULL if no match
+ */
+ if (kev->flags & EV_ADD) {
+ int attach = 0;
+
+ if (kn == NULL) {
+ kn = knote_alloc();
+ if (kn == NULL)
+ return (ENOMEM);
+ if (fp != NULL)
+ fhold(fp);
+ kn->kn_fp = fp;
+ kn->kn_kq = kq;
+ kn->kn_fop = fops;
+ attach = 1;
+ }
+ kn->kn_sfflags = kev->fflags;
+ kn->kn_sdata = kev->data;
+ kev->fflags = 0;
+ kev->data = 0;
+ kn->kn_kevent = *kev;
+
+ if (attach) {
+ knote_attach(kn, fdp);
+ if ((error = fops->f_attach(kn)) != 0) {
+ knote_drop(kn, p);
+ goto done;
+ }
+ }
+ if (kn->kn_fop->f_event(kn, 0))
+ KNOTE_ACTIVATE(kn);
+ } else if (kev->flags & EV_DELETE) {
+ kn->kn_fop->f_detach(kn);
+ knote_drop(kn, p);
+ goto done;
+ }
+
+ if ((kev->flags & EV_DISABLE) &&
+ ((kn->kn_status & KN_DISABLED) == 0)) {
+ s = splhigh();
+ kn->kn_status |= KN_DISABLED;
+ splx(s);
+ }
+
+ if ((kev->flags & EV_ENABLE) && (kn->kn_status & KN_DISABLED)) {
+ s = splhigh();
+ kn->kn_status &= ~KN_DISABLED;
+ if ((kn->kn_status & KN_ACTIVE) &&
+ ((kn->kn_status & KN_QUEUED) == 0))
+ knote_enqueue(kn);
+ splx(s);
+ }
+
+done:
+ return (error);
+}
+
+static int
+kqueue_scan(struct file *fp, int maxevents, struct kevent *ulistp,
+ struct timespec *tsp, struct proc *p)
+{
+ struct kqueue *kq = (struct kqueue *)fp->f_data;
+ struct kevent *kevp;
+ struct timeval atv, rtv, ttv;
+ struct knote *kn, marker;
+ int s, count, timeout, nkev = 0, error = 0;
+
+ count = maxevents;
+ if (count == 0)
+ goto done;
+
+ if (tsp != NULL) {
+ TIMESPEC_TO_TIMEVAL(&atv, tsp);
+ if (itimerfix(&atv)) {
+ error = EINVAL;
+ goto done;
+ }
+ timeout = atv.tv_sec > 24 * 60 * 60 ?
+ 24 * 60 * 60 * hz : tvtohz(&atv);
+ getmicrouptime(&rtv);
+ timevaladd(&atv, &rtv);
+ } else {
+ atv.tv_sec = 0;
+ timeout = 0;
+ }
+ goto start;
+
+retry:
+ if (atv.tv_sec) {
+ getmicrouptime(&rtv);
+ if (timevalcmp(&rtv, &atv, >=))
+ goto done;
+ ttv = atv;
+ timevalsub(&ttv, &rtv);
+ timeout = ttv.tv_sec > 24 * 60 * 60 ?
+ 24 * 60 * 60 * hz : tvtohz(&ttv);
+ }
+
+start:
+ kevp = kq->kq_kev;
+ s = splhigh();
+ if (kq->kq_count == 0) {
+ kq->kq_state |= KQ_SLEEP;
+ error = tsleep(kq, PSOCK | PCATCH, "kqread", timeout);
+ splx(s);
+ if (error == 0)
+ goto retry;
+ /* don't restart after signals... */
+ if (error == ERESTART)
+ error = EINTR;
+ else if (error == EWOULDBLOCK)
+ error = 0;
+ goto done;
+ }
+
+ TAILQ_INSERT_TAIL(&kq->kq_head, &marker, kn_tqe);
+ while (count) {
+ kn = TAILQ_FIRST(&kq->kq_head);
+ TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe);
+ if (kn == &marker) {
+ splx(s);
+ if (count == maxevents)
+ goto retry;
+ goto done;
+ }
+ if (kn->kn_status & KN_DISABLED) {
+ kn->kn_status &= ~KN_QUEUED;
+ kq->kq_count--;
+ continue;
+ }
+ if ((kn->kn_flags & EV_ONESHOT) == 0 &&
+ kn->kn_fop->f_event(kn, 0) == 0) {
+ kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE);
+ kq->kq_count--;
+ continue;
+ }
+ *kevp = kn->kn_kevent;
+ kevp++;
+ nkev++;
+ if (kn->kn_flags & EV_ONESHOT) {
+ kn->kn_status &= ~KN_QUEUED;
+ kq->kq_count--;
+ splx(s);
+ kn->kn_fop->f_detach(kn);
+ knote_drop(kn, p);
+ s = splhigh();
+ } else if (kn->kn_flags & EV_CLEAR) {
+ kn->kn_data = 0;
+ kn->kn_fflags = 0;
+ kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE);
+ kq->kq_count--;
+ } else {
+ TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe);
+ }
+ count--;
+ if (nkev == KQ_NEVENTS) {
+ splx(s);
+ error = copyout((caddr_t)&kq->kq_kev, (caddr_t)ulistp,
+ sizeof(struct kevent) * nkev);
+ if (error)
+ break;
+ ulistp += nkev;
+ nkev = 0;
+ kevp = kq->kq_kev;
+ s = splhigh();
+ }
+ }
+ TAILQ_REMOVE(&kq->kq_head, &marker, kn_tqe);
+ splx(s);
+done:
+ if (nkev != 0)
+ error = copyout((caddr_t)&kq->kq_kev, (caddr_t)ulistp,
+ sizeof(struct kevent) * nkev);
+ p->p_retval[0] = maxevents - count;
+ return (error);
+}
+
+/*
+ * XXX
+ * This could be expanded to call kqueue_scan, if desired.
+ */
+/*ARGSUSED*/
+static int
+kqueue_read(struct file *fp, struct uio *uio, struct ucred *cred,
+ int flags, struct proc *p)
+{
+ return (ENXIO);
+}
+
+/*ARGSUSED*/
+static int
+kqueue_write(struct file *fp, struct uio *uio, struct ucred *cred,
+ int flags, struct proc *p)
+{
+ return (ENXIO);
+}
+
+/*ARGSUSED*/
+static int
+kqueue_ioctl(struct file *fp, u_long com, caddr_t data, struct proc *p)
+{
+ return (ENOTTY);
+}
+
+/*ARGSUSED*/
+static int
+kqueue_poll(struct file *fp, int events, struct ucred *cred, struct proc *p)
+{
+ struct kqueue *kq = (struct kqueue *)fp->f_data;
+ int revents = 0;
+ int s = splnet();
+
+ if (events & (POLLIN | POLLRDNORM)) {
+ if (kq->kq_count) {
+ revents |= events & (POLLIN | POLLRDNORM);
+ } else {
+ selrecord(p, &kq->kq_sel);
+ kq->kq_state |= KQ_SEL;
+ }
+ }
+ splx(s);
+ return (revents);
+}
+
+/*ARGSUSED*/
+static int
+kqueue_stat(struct file *fp, struct stat *st, struct proc *p)
+{
+ struct kqueue *kq = (struct kqueue *)fp->f_data;
+
+ bzero((void *)st, sizeof(*st));
+ st->st_size = kq->kq_count;
+ st->st_blksize = sizeof(struct kevent);
+ return (0);
+}
+
+/*ARGSUSED*/
+static int
+kqueue_close(struct file *fp, struct proc *p)
+{
+ struct kqueue *kq = (struct kqueue *)fp->f_data;
+ struct filedesc *fdp = p->p_fd;
+ struct knote **knp, *kn, *kn0;
+ int i;
+
+ for (i = 0; i < fdp->fd_knlistsize; i++) {
+ knp = &SLIST_FIRST(&fdp->fd_knlist[i]);
+ kn = *knp;
+ while (kn != NULL) {
+ kn0 = SLIST_NEXT(kn, kn_link);
+ if (kq == kn->kn_kq) {
+ kn->kn_fop->f_detach(kn);
+ fdrop(kn->kn_fp, p);
+ knote_free(kn);
+ *knp = kn0;
+ } else {
+ knp = &SLIST_NEXT(kn, kn_link);
+ }
+ kn = kn0;
+ }
+ }
+ if (fdp->fd_knhashmask != 0) {
+ for (i = 0; i < fdp->fd_knhashmask + 1; i++) {
+ knp = &SLIST_FIRST(&fdp->fd_knhash[i]);
+ kn = *knp;
+ while (kn != NULL) {
+ kn0 = SLIST_NEXT(kn, kn_link);
+ if (kq == kn->kn_kq) {
+ kn->kn_fop->f_detach(kn);
+ /* XXX non-fd release of kn->kn_ptr */
+ knote_free(kn);
+ *knp = kn0;
+ } else {
+ knp = &SLIST_NEXT(kn, kn_link);
+ }
+ kn = kn0;
+ }
+ }
+ }
+ free(kq, M_TEMP);
+ fp->f_data = NULL;
+
+ return (0);
+}
+
+static void
+kqueue_wakeup(struct kqueue *kq)
+{
+
+ if (kq->kq_state & KQ_SLEEP) {
+ kq->kq_state &= ~KQ_SLEEP;
+ wakeup(kq);
+ }
+ if (kq->kq_state & KQ_SEL) {
+ kq->kq_state &= ~KQ_SEL;
+ selwakeup(&kq->kq_sel);
+ }
+ KNOTE(&kq->kq_sel.si_note, 0);
+}
+
+/*
+ * walk down a list of knotes, activating them if their event has triggered.
+ */
+void
+knote(struct klist *list, long hint)
+{
+ struct knote *kn;
+
+ SLIST_FOREACH(kn, list, kn_selnext)
+ if (kn->kn_fop->f_event(kn, hint))
+ KNOTE_ACTIVATE(kn);
+}
+
+/*
+ * remove all knotes from a specified klist
+ */
+void
+knote_remove(struct proc *p, struct klist *list)
+{
+ struct knote *kn;
+
+ while ((kn = SLIST_FIRST(list)) != NULL) {
+ kn->kn_fop->f_detach(kn);
+ knote_drop(kn, p);
+ }
+}
+
+/*
+ * remove all knotes referencing a specified fd
+ */
+void
+knote_fdclose(struct proc *p, int fd)
+{
+ struct filedesc *fdp = p->p_fd;
+ struct klist *list = &fdp->fd_knlist[fd];
+
+ knote_remove(p, list);
+}
+
+static void
+knote_attach(struct knote *kn, struct filedesc *fdp)
+{
+ struct klist *list;
+ int size;
+
+ if (! kn->kn_fop->f_isfd) {
+ if (fdp->fd_knhashmask == 0)
+ fdp->fd_knhash = hashinit(KN_HASHSIZE, M_TEMP,
+ &fdp->fd_knhashmask);
+ list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)];
+ goto done;
+ }
+
+ if (fdp->fd_knlistsize <= kn->kn_id) {
+ size = fdp->fd_knlistsize;
+ while (size <= kn->kn_id)
+ size += KQEXTENT;
+ MALLOC(list, struct klist *,
+ size * sizeof(struct klist *), M_TEMP, M_WAITOK);
+ bcopy((caddr_t)fdp->fd_knlist, (caddr_t)list,
+ fdp->fd_knlistsize * sizeof(struct klist *));
+ bzero((caddr_t)list +
+ fdp->fd_knlistsize * sizeof(struct klist *),
+ (size - fdp->fd_knlistsize) * sizeof(struct klist *));
+ if (fdp->fd_knlist != NULL)
+ FREE(fdp->fd_knlist, M_TEMP);
+ fdp->fd_knlistsize = size;
+ fdp->fd_knlist = list;
+ }
+ list = &fdp->fd_knlist[kn->kn_id];
+done:
+ SLIST_INSERT_HEAD(list, kn, kn_link);
+ kn->kn_status = 0;
+}
+
+/*
+ * should be called at spl == 0, since we don't want to hold spl
+ * while calling fdrop and free.
+ */
+static void
+knote_drop(struct knote *kn, struct proc *p)
+{
+ struct filedesc *fdp = p->p_fd;
+ struct klist *list;
+
+ if (kn->kn_fop->f_isfd)
+ list = &fdp->fd_knlist[kn->kn_id];
+ else
+ list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)];
+
+ SLIST_REMOVE(list, kn, knote, kn_link);
+ if (kn->kn_status & KN_QUEUED)
+ knote_dequeue(kn);
+ if (kn->kn_fop->f_isfd)
+ fdrop(kn->kn_fp, p);
+ knote_free(kn);
+}
+
+
+static void
+knote_enqueue(struct knote *kn)
+{
+ struct kqueue *kq = kn->kn_kq;
+ int s = splhigh();
+
+ TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe);
+ kn->kn_status |= KN_QUEUED;
+ kq->kq_count++;
+ splx(s);
+ kqueue_wakeup(kq);
+}
+
+static void
+knote_dequeue(struct knote *kn)
+{
+ struct kqueue *kq = kn->kn_kq;
+ int s = splhigh();
+
+ TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe);
+ kn->kn_status &= ~KN_QUEUED;
+ kq->kq_count--;
+ splx(s);
+}
+
+static void
+knote_init(void)
+{
+ knote_zone = zinit("KNOTE", sizeof(struct knote), 0, 0, 1);
+}
+SYSINIT(knote, SI_SUB_PSEUDO, SI_ORDER_ANY, knote_init, NULL)
+
+static struct knote *
+knote_alloc(void)
+{
+ return ((struct knote *)zalloc(knote_zone));
+}
+
+static void
+knote_free(struct knote *kn)
+{
+ zfree(knote_zone, kn);
+}
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