X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/43866e378188c25dd1e2208016ab3cbeb086ae6c..36401178fd6817c043cc00b0c00c7f723e58efae:/bsd/kern/kern_event.c diff --git a/bsd/kern/kern_event.c b/bsd/kern/kern_event.c index f298f525b..5c940792d 100644 --- a/bsd/kern/kern_event.c +++ b/bsd/kern/kern_event.c @@ -1,16 +1,19 @@ /* - * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved. * - * @APPLE_LICENSE_HEADER_START@ - * - * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved. + * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in - * compliance with the License. Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this - * file. + * compliance with the License. The rights granted to you under the License + * may not be used to create, or enable the creation or redistribution of, + * unlawful or unlicensed copies of an Apple operating system, or to + * circumvent, violate, or enable the circumvention or violation of, any + * terms of an Apple operating system software license agreement. + * + * Please obtain a copy of the License at + * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER @@ -20,13 +23,1988 @@ * Please see the License for the specific language governing rights and * limitations under the License. * - * @APPLE_LICENSE_HEADER_END@ + * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ + * + */ +/*- + * Copyright (c) 1999,2000,2001 Jonathan Lemon + * 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. */ /* * @(#)kern_event.c 1.0 (3/31/2000) */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include +#include "kpi_mbuf_internal.h" + +MALLOC_DEFINE(M_KQUEUE, "kqueue", "memory for kqueue system"); + +static inline void kqlock(struct kqueue *kq); +static inline void kqunlock(struct kqueue *kq); + +static int kqlock2knoteuse(struct kqueue *kq, struct knote *kn); +static int kqlock2knoteusewait(struct kqueue *kq, struct knote *kn); +static int kqlock2knotedrop(struct kqueue *kq, struct knote *kn); +static int knoteuse2kqlock(struct kqueue *kq, struct knote *kn); + +static void kqueue_wakeup(struct kqueue *kq); +static int kqueue_read(struct fileproc *fp, struct uio *uio, + int flags, vfs_context_t ctx); +static int kqueue_write(struct fileproc *fp, struct uio *uio, + int flags, vfs_context_t ctx); +static int kqueue_ioctl(struct fileproc *fp, u_long com, caddr_t data, + vfs_context_t ctx); +static int kqueue_select(struct fileproc *fp, int which, void *wql, + vfs_context_t ctx); +static int kqueue_close(struct fileglob *fp, vfs_context_t ctx); +static int kqueue_kqfilter(struct fileproc *fp, struct knote *kn, vfs_context_t ctx); +extern int kqueue_stat(struct fileproc *fp, void *ub, int isstat64, vfs_context_t ctx); + +static struct fileops kqueueops = { + kqueue_read, + kqueue_write, + kqueue_ioctl, + kqueue_select, + kqueue_close, + kqueue_kqfilter, + 0 +}; + +static int kevent_copyin(user_addr_t *addrp, struct kevent *kevp, struct proc *p); +static int kevent_copyout(struct kevent *kevp, user_addr_t *addrp, struct proc *p); + +static int kevent_callback(struct kqueue *kq, struct kevent *kevp, void *data); +static void kevent_continue(struct kqueue *kq, void *data, int error); +static void kevent_scan_continue(void *contp, wait_result_t wait_result); +static int kevent_process(struct kqueue *kq, kevent_callback_t callback, + void *data, int *countp, struct proc *p); +static void knote_put(struct knote *kn); +static int knote_fdpattach(struct knote *kn, struct filedesc *fdp, struct proc *p); +static void knote_drop(struct knote *kn, struct proc *p); +static void knote_activate(struct knote *kn); +static void knote_deactivate(struct knote *kn); +static void knote_enqueue(struct knote *kn); +static void knote_dequeue(struct knote *kn); +static struct knote *knote_alloc(void); +static void knote_free(struct knote *kn); + +static int filt_fileattach(struct knote *kn); +static struct filterops file_filtops = + { 1, filt_fileattach, NULL, NULL }; + +static void filt_kqdetach(struct knote *kn); +static int filt_kqueue(struct knote *kn, long hint); +static struct filterops kqread_filtops = + { 1, NULL, filt_kqdetach, filt_kqueue }; + +/* + * placeholder for not-yet-implemented filters + */ +static int filt_badattach(struct knote *kn); +static struct filterops bad_filtops = + { 0, filt_badattach, 0 , 0 }; + +static int filt_procattach(struct knote *kn); +static void filt_procdetach(struct knote *kn); +static int filt_proc(struct knote *kn, long hint); + +static struct filterops proc_filtops = + { 0, filt_procattach, filt_procdetach, filt_proc }; + +extern struct filterops fs_filtops; + +extern struct filterops sig_filtops; + + +/* Timer filter */ +static int filt_timercompute(struct knote *kn, uint64_t *abs_time); +static void filt_timerexpire(void *knx, void *param1); +static int filt_timerattach(struct knote *kn); +static void filt_timerdetach(struct knote *kn); +static int filt_timer(struct knote *kn, long hint); + +static struct filterops timer_filtops = + { 0, filt_timerattach, filt_timerdetach, filt_timer }; + +/* to avoid arming timers that fire quicker than we can handle */ +static uint64_t filt_timerfloor = 0; + +static lck_mtx_t _filt_timerlock; +static void filt_timerlock(void); +static void filt_timerunlock(void); + +static zone_t knote_zone; + +#define KN_HASH(val, mask) (((val) ^ (val >> 8)) & (mask)) + +#if 0 +extern struct filterops aio_filtops; +#endif + +/* + * Table for for all system-defined filters. + */ +static struct filterops *sysfilt_ops[] = { + &file_filtops, /* EVFILT_READ */ + &file_filtops, /* EVFILT_WRITE */ +#if 0 + &aio_filtops, /* EVFILT_AIO */ +#else + &bad_filtops, /* EVFILT_AIO */ +#endif + &file_filtops, /* EVFILT_VNODE */ + &proc_filtops, /* EVFILT_PROC */ + &sig_filtops, /* EVFILT_SIGNAL */ + &timer_filtops, /* EVFILT_TIMER */ + &bad_filtops, /* EVFILT_MACHPORT */ + &fs_filtops /* EVFILT_FS */ +}; + +/* + * kqueue/note lock attributes and implementations + * + * kqueues have locks, while knotes have use counts + * Most of the knote state is guarded by the object lock. + * the knote "inuse" count and status use the kqueue lock. + */ +lck_grp_attr_t * kq_lck_grp_attr; +lck_grp_t * kq_lck_grp; +lck_attr_t * kq_lck_attr; + +static inline void +kqlock(struct kqueue *kq) +{ + lck_spin_lock(&kq->kq_lock); +} + +static inline void +kqunlock(struct kqueue *kq) +{ + lck_spin_unlock(&kq->kq_lock); +} + +/* + * Convert a kq lock to a knote use referece. + * + * If the knote is being dropped, we can't get + * a use reference, so just return with it + * still locked. + * + * - kq locked at entry + * - unlock on exit if we get the use reference + */ +static int +kqlock2knoteuse(struct kqueue *kq, struct knote *kn) +{ + if (kn->kn_status & KN_DROPPING) + return 0; + kn->kn_inuse++; + kqunlock(kq); + return 1; + } + +/* + * Convert a kq lock to a knote use referece. + * + * If the knote is being dropped, we can't get + * a use reference, so just return with it + * still locked. + * + * - kq locked at entry + * - kq always unlocked on exit + */ +static int +kqlock2knoteusewait(struct kqueue *kq, struct knote *kn) +{ + if (!kqlock2knoteuse(kq, kn)) { + kn->kn_status |= KN_DROPWAIT; + assert_wait(&kn->kn_status, THREAD_UNINT); + kqunlock(kq); + thread_block(THREAD_CONTINUE_NULL); + return 0; + } + return 1; + } + +/* + * Convert from a knote use reference back to kq lock. + * + * Drop a use reference and wake any waiters if + * this is the last one. + * + * The exit return indicates if the knote is + * still alive - but the kqueue lock is taken + * unconditionally. + */ +static int +knoteuse2kqlock(struct kqueue *kq, struct knote *kn) +{ + kqlock(kq); + if ((--kn->kn_inuse == 0) && + (kn->kn_status & KN_USEWAIT)) { + kn->kn_status &= ~KN_USEWAIT; + thread_wakeup(&kn->kn_inuse); + } + return ((kn->kn_status & KN_DROPPING) == 0); + } + +/* + * Convert a kq lock to a knote drop referece. + * + * If the knote is in use, wait for the use count + * to subside. We first mark our intention to drop + * it - keeping other users from "piling on." + * If we are too late, we have to wait for the + * other drop to complete. + * + * - kq locked at entry + * - always unlocked on exit. + * - caller can't hold any locks that would prevent + * the other dropper from completing. + */ +static int +kqlock2knotedrop(struct kqueue *kq, struct knote *kn) +{ + + if ((kn->kn_status & KN_DROPPING) == 0) { + kn->kn_status |= KN_DROPPING; + if (kn->kn_inuse > 0) { + kn->kn_status |= KN_USEWAIT; + assert_wait(&kn->kn_inuse, THREAD_UNINT); + kqunlock(kq); + thread_block(THREAD_CONTINUE_NULL); + } else + kqunlock(kq); + return 1; + } else { + kn->kn_status |= KN_DROPWAIT; + assert_wait(&kn->kn_status, THREAD_UNINT); + kqunlock(kq); + thread_block(THREAD_CONTINUE_NULL); + return 0; + } +} + +/* + * Release a knote use count reference. + */ +static void +knote_put(struct knote *kn) +{ + struct kqueue *kq = kn->kn_kq; + + kqlock(kq); + if ((--kn->kn_inuse == 0) && + (kn->kn_status & KN_USEWAIT)) { + kn->kn_status &= ~KN_USEWAIT; + thread_wakeup(&kn->kn_inuse); + } + kqunlock(kq); + } + + + +static int +filt_fileattach(struct knote *kn) +{ + + return (fo_kqfilter(kn->kn_fp, kn, vfs_context_current())); +} + +#define f_flag f_fglob->fg_flag +#define f_type f_fglob->fg_type +#define f_msgcount f_fglob->fg_msgcount +#define f_cred f_fglob->fg_cred +#define f_ops f_fglob->fg_ops +#define f_offset f_fglob->fg_offset +#define f_data f_fglob->fg_data + +static void +filt_kqdetach(struct knote *kn) +{ + struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data; + + kqlock(kq); + KNOTE_DETACH(&kq->kq_sel.si_note, kn); + kqunlock(kq); +} + +/*ARGSUSED*/ +static int +filt_kqueue(struct knote *kn, __unused 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; + + assert(PID_MAX < NOTE_PDATAMASK); + + if ((kn->kn_sfflags & (NOTE_TRACK | NOTE_TRACKERR | NOTE_CHILD)) != 0) + return(ENOTSUP); + + p = proc_find(kn->kn_id); + if (p == NULL) { + return (ESRCH); + } + + proc_klist_lock(); + + kn->kn_flags |= EV_CLEAR; /* automatically set */ + kn->kn_ptr.p_proc = p; /* store the proc handle */ + + KNOTE_ATTACH(&p->p_klist, kn); + + proc_klist_unlock(); + + proc_rele(p); + + return (0); +} + +/* + * The knote may be attached to a different process, which may exit, + * leaving nothing for the knote to be attached to. In that case, + * the pointer to the process will have already been nulled out. + */ +static void +filt_procdetach(struct knote *kn) +{ + struct proc *p; + + proc_klist_lock(); + + p = kn->kn_ptr.p_proc; + if (p != PROC_NULL) { + kn->kn_ptr.p_proc = PROC_NULL; + KNOTE_DETACH(&p->p_klist, kn); + } + + proc_klist_unlock(); +} + +static int +filt_proc(struct knote *kn, long hint) +{ + struct proc * p; + + /* hint is 0 when called from above */ + if (hint != 0) { + u_int event; + + /* ALWAYS CALLED WITH proc_klist_lock when (hint != 0) */ + + /* + * 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; + + /* + * If this is the last possible event for the + * knote, unlink this knote from the process + * before the process goes away. + */ + if (event == NOTE_REAP || (event == NOTE_EXIT && !(kn->kn_sfflags & NOTE_REAP))) { + kn->kn_flags |= (EV_EOF | EV_ONESHOT); + p = kn->kn_ptr.p_proc; + if (p != PROC_NULL) { + kn->kn_ptr.p_proc = PROC_NULL; + KNOTE_DETACH(&p->p_klist, kn); + } + return (1); + } + + } + + /* atomic check, no locking need when called from above */ + return (kn->kn_fflags != 0); +} + +/* + * filt_timercompute - compute absolute timeout + * + * The saved-data field in the knote contains the + * time value. The saved filter-flags indicates + * the unit of measurement. + * + * If the timeout is not absolute, adjust it for + * the current time. + */ +static int +filt_timercompute(struct knote *kn, uint64_t *abs_time) +{ + uint64_t multiplier; + uint64_t raw; + + switch (kn->kn_sfflags & (NOTE_SECONDS|NOTE_USECONDS|NOTE_NSECONDS)) { + case NOTE_SECONDS: + multiplier = NSEC_PER_SEC; + break; + case NOTE_USECONDS: + multiplier = NSEC_PER_USEC; + break; + case NOTE_NSECONDS: + multiplier = 1; + break; + case 0: /* milliseconds (default) */ + multiplier = NSEC_PER_SEC / 1000; + break; + default: + return EINVAL; + } + nanoseconds_to_absolutetime((uint64_t)kn->kn_sdata * multiplier, &raw); + if (raw <= filt_timerfloor) { + *abs_time = 0; + return 0; + } + if ((kn->kn_sfflags & NOTE_ABSOLUTE) == NOTE_ABSOLUTE) { + uint32_t seconds, nanoseconds; + uint64_t now; + + clock_get_calendar_nanotime(&seconds, &nanoseconds); + nanoseconds_to_absolutetime((uint64_t)seconds * NSEC_PER_SEC + nanoseconds, + &now); + if (now >= raw + filt_timerfloor) { + *abs_time = 0; + return 0; + } + raw -= now; + } + clock_absolutetime_interval_to_deadline(raw, abs_time); + return 0; +} + +/* + * filt_timerexpire - the timer callout routine + * + * Just propagate the timer event into the knote + * filter routine (by going through the knote + * synchronization point). Pass a hint to + * indicate this is a real event, not just a + * query from above. + */ +static void +filt_timerexpire(void *knx, __unused void *spare) +{ + struct klist timer_list; + struct knote *kn = knx; + + /* no "object" for timers, so fake a list */ + SLIST_INIT(&timer_list); + SLIST_INSERT_HEAD(&timer_list, kn, kn_selnext); + KNOTE(&timer_list, 1); +} + +/* + * data contains amount of time to sleep, in milliseconds, + * or a pointer to a timespec structure. + */ +static int +filt_timerattach(struct knote *kn) +{ + thread_call_t callout; + uint64_t deadline; + int error; + + error = filt_timercompute(kn, &deadline); + if (error) + return (error); + + if (deadline) { + callout = thread_call_allocate(filt_timerexpire, kn); + if (NULL == callout) + return (ENOMEM); + } else { + /* handle as immediate */ + kn->kn_sdata = 0; + callout = NULL; + } + + filt_timerlock(); + kn->kn_hook = (caddr_t)callout; + + /* absolute=EV_ONESHOT */ + if (kn->kn_sfflags & NOTE_ABSOLUTE) + kn->kn_flags |= EV_ONESHOT; + + if (deadline) { + /* all others - if not faking immediate */ + kn->kn_flags |= EV_CLEAR; + thread_call_enter_delayed(callout, deadline); + kn->kn_hookid = 0; + } else { + /* fake immediate */ + kn->kn_hookid = 1; + } + filt_timerunlock(); + return (0); +} + +static void +filt_timerdetach(struct knote *kn) +{ + thread_call_t callout; + + filt_timerlock(); + callout = (thread_call_t)kn->kn_hook; + if (callout != NULL) { + boolean_t cancelled; + + /* cancel the callout if we can */ + cancelled = thread_call_cancel(callout); + if (cancelled) { + /* got it, just free it */ + kn->kn_hook = NULL; + filt_timerunlock(); + thread_call_free(callout); + return; + } + /* we have to wait for the expire routine. */ + kn->kn_hookid = -1; /* we are detaching */ + assert_wait(&kn->kn_hook, THREAD_UNINT); + filt_timerunlock(); + thread_block(THREAD_CONTINUE_NULL); + assert(kn->kn_hook == NULL); + return; + } + /* nothing to do */ + filt_timerunlock(); +} + + + +static int +filt_timer(struct knote *kn, __unused long hint) +{ + int result; + + if (hint) { + /* real timer pop */ + thread_call_t callout; + boolean_t detaching; + + filt_timerlock(); + + kn->kn_data++; + + detaching = (kn->kn_hookid < 0); + callout = (thread_call_t)kn->kn_hook; + + if (!detaching && (kn->kn_flags & EV_ONESHOT) == 0) { + uint64_t deadline; + int error; + + /* user input data may have changed - deal */ + error = filt_timercompute(kn, &deadline); + if (error) { + kn->kn_flags |= EV_ERROR; + kn->kn_data = error; + } else if (deadline == 0) { + /* revert to fake immediate */ + kn->kn_flags &= ~EV_CLEAR; + kn->kn_sdata = 0; + kn->kn_hookid = 1; + } else { + /* keep the callout and re-arm */ + thread_call_enter_delayed(callout, deadline); + filt_timerunlock(); + return 1; + } + } + kn->kn_hook = NULL; + filt_timerunlock(); + thread_call_free(callout); + + /* if someone is waiting for timer to pop */ + if (detaching) + thread_wakeup(&kn->kn_hook); + + return 1; + } + + /* user-query */ + filt_timerlock(); + + /* change fake timer to real if needed */ + while (kn->kn_hookid > 0 && kn->kn_sdata > 0) { + int error; + + /* update the fake timer (make real) */ + kn->kn_hookid = 0; + kn->kn_data = 0; + filt_timerunlock(); + error = filt_timerattach(kn); + filt_timerlock(); + if (error) { + kn->kn_flags |= EV_ERROR; + kn->kn_data = error; + filt_timerunlock(); + return 1; + } + } + + /* if still fake, pretend it fired */ + if (kn->kn_hookid > 0) + kn->kn_data = 1; + + result = (kn->kn_data != 0); + filt_timerunlock(); + return result; +} + +static void +filt_timerlock(void) +{ + lck_mtx_lock(&_filt_timerlock); +} + +static void +filt_timerunlock(void) +{ + lck_mtx_unlock(&_filt_timerlock); +} + +/* + * JMM - placeholder for not-yet-implemented filters + */ +static int +filt_badattach(__unused struct knote *kn) +{ + return(ENOTSUP); +} + + +struct kqueue * +kqueue_alloc(struct proc *p) +{ + struct filedesc *fdp = p->p_fd; + struct kqueue *kq; + + MALLOC_ZONE(kq, struct kqueue *, sizeof(struct kqueue), M_KQUEUE, M_WAITOK); + if (kq != NULL) { + bzero(kq, sizeof(struct kqueue)); + lck_spin_init(&kq->kq_lock, kq_lck_grp, kq_lck_attr); + TAILQ_INIT(&kq->kq_head); + TAILQ_INIT(&kq->kq_inprocess); + kq->kq_p = p; + } + + if (fdp->fd_knlistsize < 0) { + proc_fdlock(p); + if (fdp->fd_knlistsize < 0) + fdp->fd_knlistsize = 0; /* this process has had a kq */ + proc_fdunlock(p); + } + + return kq; +} + + +/* + * kqueue_dealloc - detach all knotes from a kqueue and free it + * + * We walk each list looking for knotes referencing this + * this kqueue. If we find one, we try to drop it. But + * if we fail to get a drop reference, that will wait + * until it is dropped. So, we can just restart again + * safe in the assumption that the list will eventually + * not contain any more references to this kqueue (either + * we dropped them all, or someone else did). + * + * Assumes no new events are being added to the kqueue. + * Nothing locked on entry or exit. + */ +void +kqueue_dealloc(struct kqueue *kq) +{ + struct proc *p = kq->kq_p; + struct filedesc *fdp = p->p_fd; + struct knote *kn; + int i; + + proc_fdlock(p); + for (i = 0; i < fdp->fd_knlistsize; i++) { + kn = SLIST_FIRST(&fdp->fd_knlist[i]); + while (kn != NULL) { + if (kq == kn->kn_kq) { + kqlock(kq); + proc_fdunlock(p); + /* drop it ourselves or wait */ + if (kqlock2knotedrop(kq, kn)) { + kn->kn_fop->f_detach(kn); + knote_drop(kn, p); + } + proc_fdlock(p); + /* start over at beginning of list */ + kn = SLIST_FIRST(&fdp->fd_knlist[i]); + continue; + } + kn = SLIST_NEXT(kn, kn_link); + } + } + if (fdp->fd_knhashmask != 0) { + for (i = 0; i < (int)fdp->fd_knhashmask + 1; i++) { + kn = SLIST_FIRST(&fdp->fd_knhash[i]); + while (kn != NULL) { + if (kq == kn->kn_kq) { + kqlock(kq); + proc_fdunlock(p); + /* drop it ourselves or wait */ + if (kqlock2knotedrop(kq, kn)) { + kn->kn_fop->f_detach(kn); + knote_drop(kn, p); + } + proc_fdlock(p); + /* start over at beginning of list */ + kn = SLIST_FIRST(&fdp->fd_knhash[i]); + continue; + } + kn = SLIST_NEXT(kn, kn_link); + } + } + } + proc_fdunlock(p); + lck_spin_destroy(&kq->kq_lock, kq_lck_grp); + FREE_ZONE(kq, sizeof(struct kqueue), M_KQUEUE); +} + +int +kqueue(struct proc *p, __unused struct kqueue_args *uap, register_t *retval) +{ + struct kqueue *kq; + struct fileproc *fp; + int fd, error; + + error = falloc(p, &fp, &fd, vfs_context_current()); + if (error) { + return (error); + } + + kq = kqueue_alloc(p); + if (kq == NULL) { + fp_free(p, fd, fp); + return (ENOMEM); + } + + fp->f_flag = FREAD | FWRITE; + fp->f_type = DTYPE_KQUEUE; + fp->f_ops = &kqueueops; + fp->f_data = (caddr_t)kq; + + proc_fdlock(p); + procfdtbl_releasefd(p, fd, NULL); + fp_drop(p, fd, fp, 1); + proc_fdunlock(p); + + *retval = fd; + return (error); +} + +int +kqueue_portset_np(__unused struct proc *p, + __unused struct kqueue_portset_np_args *uap, + __unused register_t *retval) +{ + /* JMM - Placeholder for now */ + return (ENOTSUP); +} + +int +kqueue_from_portset_np(__unused struct proc *p, + __unused struct kqueue_from_portset_np_args *uap, + __unused register_t *retval) +{ + /* JMM - Placeholder for now */ + return (ENOTSUP); +} + +static int +kevent_copyin(user_addr_t *addrp, struct kevent *kevp, struct proc *p) +{ + int advance; + int error; + + if (IS_64BIT_PROCESS(p)) { + struct user_kevent kev64; + + advance = sizeof(kev64); + error = copyin(*addrp, (caddr_t)&kev64, advance); + if (error) + return error; + kevp->ident = CAST_DOWN(uintptr_t, kev64.ident); + kevp->filter = kev64.filter; + kevp->flags = kev64.flags; + kevp->fflags = kev64.fflags; + kevp->data = CAST_DOWN(intptr_t, kev64.data); + kevp->udata = kev64.udata; + } else { + /* + * compensate for legacy in-kernel kevent layout + * where the udata field is alredy 64-bit. + */ + advance = sizeof(*kevp) + sizeof(void *) - sizeof(user_addr_t); + error = copyin(*addrp, (caddr_t)kevp, advance); + } + if (!error) + *addrp += advance; + return error; +} + +static int +kevent_copyout(struct kevent *kevp, user_addr_t *addrp, struct proc *p) +{ + int advance; + int error; + + if (IS_64BIT_PROCESS(p)) { + struct user_kevent kev64; + + /* + * deal with the special case of a user-supplied + * value of (uintptr_t)-1. + */ + kev64.ident = (kevp->ident == (uintptr_t)-1) ? + (uint64_t)-1LL : (uint64_t)kevp->ident; + + kev64.filter = kevp->filter; + kev64.flags = kevp->flags; + kev64.fflags = kevp->fflags; + kev64.data = (int64_t) kevp->data; + kev64.udata = kevp->udata; + advance = sizeof(kev64); + error = copyout((caddr_t)&kev64, *addrp, advance); + } else { + /* + * compensate for legacy in-kernel kevent layout + * where the udata field is alredy 64-bit. + */ + advance = sizeof(*kevp) + sizeof(void *) - sizeof(user_addr_t); + error = copyout((caddr_t)kevp, *addrp, advance); + } + if (!error) + *addrp += advance; + return error; +} + +/* + * kevent_continue - continue a kevent syscall after blocking + * + * assume we inherit a use count on the kq fileglob. + */ + +static void +kevent_continue(__unused struct kqueue *kq, void *data, int error) +{ + struct _kevent *cont_args; + struct fileproc *fp; + register_t *retval; + int noutputs; + int fd; + struct proc *p = current_proc(); + + cont_args = (struct _kevent *)data; + noutputs = cont_args->eventout; + retval = cont_args->retval; + fd = cont_args->fd; + fp = cont_args->fp; + + fp_drop(p, fd, fp, 0); + + /* don't restart after signals... */ + if (error == ERESTART) + error = EINTR; + else if (error == EWOULDBLOCK) + error = 0; + if (error == 0) + *retval = noutputs; + unix_syscall_return(error); +} + +/* + * kevent - [syscall] register and wait for kernel events + * + */ + +int +kevent(struct proc *p, struct kevent_args *uap, register_t *retval) +{ + user_addr_t changelist = uap->changelist; + user_addr_t ueventlist = uap->eventlist; + int nchanges = uap->nchanges; + int nevents = uap->nevents; + int fd = uap->fd; + + struct _kevent *cont_args; + uthread_t ut; + struct kqueue *kq; + struct fileproc *fp; + struct kevent kev; + int error, noutputs; + struct timeval atv; + + /* convert timeout to absolute - if we have one */ + if (uap->timeout != USER_ADDR_NULL) { + struct timeval rtv; + if ( IS_64BIT_PROCESS(p) ) { + struct user_timespec ts; + error = copyin( uap->timeout, &ts, sizeof(ts) ); + if ((ts.tv_sec & 0xFFFFFFFF00000000ull) != 0) + error = EINVAL; + else + TIMESPEC_TO_TIMEVAL(&rtv, &ts); + } else { + struct timespec ts; + error = copyin( uap->timeout, &ts, sizeof(ts) ); + TIMESPEC_TO_TIMEVAL(&rtv, &ts); + } + if (error) + return error; + if (itimerfix(&rtv)) + return EINVAL; + getmicrouptime(&atv); + timevaladd(&atv, &rtv); + } else { + atv.tv_sec = 0; + atv.tv_usec = 0; + } + + /* get a usecount for the kq itself */ + if ((error = fp_getfkq(p, fd, &fp, &kq)) != 0) + return(error); + + /* register all the change requests the user provided... */ + noutputs = 0; + while (nchanges > 0 && error == 0) { + error = kevent_copyin(&changelist, &kev, p); + if (error) + break; + + kev.flags &= ~EV_SYSFLAGS; + error = kevent_register(kq, &kev, p); + if ((error || (kev.flags & EV_RECEIPT)) && nevents > 0) { + kev.flags = EV_ERROR; + kev.data = error; + error = kevent_copyout(&kev, &ueventlist, p); + if (error == 0) { + nevents--; + noutputs++; + } + } + nchanges--; + } + + /* store the continuation/completion data in the uthread */ + ut = (uthread_t)get_bsdthread_info(current_thread()); + cont_args = (struct _kevent *)&ut->uu_kevent.ss_kevent; + cont_args->fp = fp; + cont_args->fd = fd; + cont_args->retval = retval; + cont_args->eventlist = ueventlist; + cont_args->eventcount = nevents; + cont_args->eventout = noutputs; + + if (nevents > 0 && noutputs == 0 && error == 0) + error = kevent_scan(kq, kevent_callback, + kevent_continue, cont_args, + &atv, p); + kevent_continue(kq, cont_args, error); + /* NOTREACHED */ + return error; +} + + +/* + * kevent_callback - callback for each individual event + * + * called with nothing locked + * caller holds a reference on the kqueue + */ + +static int +kevent_callback(__unused struct kqueue *kq, struct kevent *kevp, void *data) +{ + struct _kevent *cont_args; + int error; + + cont_args = (struct _kevent *)data; + assert(cont_args->eventout < cont_args->eventcount); + + /* + * Copy out the appropriate amount of event data for this user. + */ + error = kevent_copyout(kevp, &cont_args->eventlist, current_proc()); + + /* + * If there isn't space for additional events, return + * a harmless error to stop the processing here + */ + if (error == 0 && ++cont_args->eventout == cont_args->eventcount) + error = EWOULDBLOCK; + return error; +} + +/* + * kevent_register - add a new event to a kqueue + * + * Creates a mapping between the event source and + * the kqueue via a knote data structure. + * + * Because many/most the event sources are file + * descriptor related, the knote is linked off + * the filedescriptor table for quick access. + * + * called with nothing locked + * caller holds a reference on the kqueue + */ + +int +kevent_register(struct kqueue *kq, struct kevent *kev, __unused struct proc *ctxp) +{ + struct proc *p = kq->kq_p; + struct filedesc *fdp = p->p_fd; + struct filterops *fops; + struct fileproc *fp = NULL; + struct knote *kn = NULL; + int 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); + } + + /* this iocount needs to be dropped if it is not registered */ + if (fops->f_isfd && (error = fp_lookup(p, kev->ident, &fp, 0)) != 0) + return(error); + + restart: + proc_fdlock(p); + if (fops->f_isfd) { + /* fd-based knotes are linked off the fd table */ + if (kev->ident < (u_int)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 { + /* hash non-fd knotes here too */ + 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; + } + } + + /* + * kn now contains the matching knote, or NULL if no match + */ + if (kn == NULL) { + if ((kev->flags & (EV_ADD|EV_DELETE)) == EV_ADD) { + kn = knote_alloc(); + if (kn == NULL) { + proc_fdunlock(p); + error = ENOMEM; + goto done; + } + kn->kn_fp = fp; + kn->kn_kq = kq; + kn->kn_tq = &kq->kq_head; + kn->kn_fop = fops; + kn->kn_sfflags = kev->fflags; + kn->kn_sdata = kev->data; + kev->fflags = 0; + kev->data = 0; + kn->kn_kevent = *kev; + kn->kn_inuse = 1; /* for f_attach() */ + kn->kn_status = 0; + + /* before anyone can find it */ + if (kev->flags & EV_DISABLE) + kn->kn_status |= KN_DISABLED; + + error = knote_fdpattach(kn, fdp, p); + proc_fdunlock(p); + + if (error) { + knote_free(kn); + goto done; + } + + /* + * apply reference count to knote structure, and + * do not release it at the end of this routine. + */ + fp = NULL; + + /* + * If the attach fails here, we can drop it knowing + * that nobody else has a reference to the knote. + */ + if ((error = fops->f_attach(kn)) != 0) { + knote_drop(kn, p); + goto done; + } + } else { + proc_fdunlock(p); + error = ENOENT; + goto done; + } + } else { + /* existing knote - get kqueue lock */ + kqlock(kq); + proc_fdunlock(p); + + if (kev->flags & EV_DELETE) { + knote_dequeue(kn); + kn->kn_status |= KN_DISABLED; + if (kqlock2knotedrop(kq, kn)) { + kn->kn_fop->f_detach(kn); + knote_drop(kn, p); + } + goto done; + } + + /* update status flags for existing knote */ + if (kev->flags & EV_DISABLE) { + knote_dequeue(kn); + kn->kn_status |= KN_DISABLED; + } else if (kev->flags & EV_ENABLE) { + kn->kn_status &= ~KN_DISABLED; + if (kn->kn_status & KN_ACTIVE) + knote_enqueue(kn); + } + + /* + * If somebody is in the middle of dropping this + * knote - go find/insert a new one. But we have + * wait for this one to go away first. + */ + if (!kqlock2knoteusewait(kq, kn)) + /* kqueue unlocked */ + goto restart; + + /* + * The user may change some filter values after the + * initial EV_ADD, but doing so will not reset any + * filter which have already been triggered. + */ + kn->kn_sfflags = kev->fflags; + kn->kn_sdata = kev->data; + kn->kn_kevent.udata = kev->udata; + } + + /* still have use ref on knote */ + if (kn->kn_fop->f_event(kn, 0)) { + if (knoteuse2kqlock(kq, kn)) + knote_activate(kn); + kqunlock(kq); + } else { + knote_put(kn); + } + +done: + if (fp != NULL) + fp_drop(p, kev->ident, fp, 0); + return (error); +} + +/* + * kevent_process - process the triggered events in a kqueue + * + * Walk the queued knotes and validate that they are + * really still triggered events by calling the filter + * routines (if necessary). Hold a use reference on + * the knote to avoid it being detached. For each event + * that is still considered triggered, invoke the + * callback routine provided. + * + * caller holds a reference on the kqueue. + * kqueue locked on entry and exit - but may be dropped + */ + +static int +kevent_process(struct kqueue *kq, + kevent_callback_t callback, + void *data, + int *countp, + struct proc *p) +{ + struct knote *kn; + struct kevent kev; + int nevents; + int error; + + restart: + if (kq->kq_count == 0) { + *countp = 0; + return 0; + } + + /* if someone else is processing the queue, wait */ + if (!TAILQ_EMPTY(&kq->kq_inprocess)) { + assert_wait(&kq->kq_inprocess, THREAD_UNINT); + kq->kq_state |= KQ_PROCWAIT; + kqunlock(kq); + thread_block(THREAD_CONTINUE_NULL); + kqlock(kq); + goto restart; + } + + error = 0; + nevents = 0; + while (error == 0 && + (kn = TAILQ_FIRST(&kq->kq_head)) != NULL) { + + /* + * Take note off the active queue. + * + * Non-EV_ONESHOT events must be re-validated. + * + * Convert our lock to a use-count and call the event's + * filter routine to update. + * + * If the event is valid, or triggered while the kq + * is unlocked, move to the inprocess queue for processing. + */ + + if ((kn->kn_flags & EV_ONESHOT) == 0) { + int result; + knote_deactivate(kn); + + if (kqlock2knoteuse(kq, kn)) { + + /* call the filter with just a ref */ + result = kn->kn_fop->f_event(kn, 0); + + /* if it's still alive, make sure it's active */ + if (knoteuse2kqlock(kq, kn) && result) { + /* may have been reactivated in filter*/ + if (!(kn->kn_status & KN_ACTIVE)) { + knote_activate(kn); + } + } else { + continue; + } + } else { + continue; + } + } + + /* knote is active: move onto inprocess queue */ + assert(kn->kn_tq == &kq->kq_head); + TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe); + kn->kn_tq = &kq->kq_inprocess; + TAILQ_INSERT_TAIL(&kq->kq_inprocess, kn, kn_tqe); + + /* + * Got a valid triggered knote with the kqueue + * still locked. Snapshot the data, and determine + * how to dispatch the knote for future events. + */ + kev = kn->kn_kevent; + + /* now what happens to it? */ + if (kn->kn_flags & EV_ONESHOT) { + knote_deactivate(kn); + if (kqlock2knotedrop(kq, kn)) { + kn->kn_fop->f_detach(kn); + knote_drop(kn, p); + } + } else if (kn->kn_flags & EV_CLEAR) { + knote_deactivate(kn); + kn->kn_data = 0; + kn->kn_fflags = 0; + kqunlock(kq); + } else { + /* + * leave on in-process queue. We'll + * move all the remaining ones back + * the kq queue and wakeup any + * waiters when we are done. + */ + kqunlock(kq); + } + + /* callback to handle each event as we find it */ + error = (callback)(kq, &kev, data); + nevents++; + + kqlock(kq); + } + + /* + * With the kqueue still locked, move any knotes + * remaining on the in-process queue back to the + * kq's queue and wake up any waiters. + */ + while ((kn = TAILQ_FIRST(&kq->kq_inprocess)) != NULL) { + assert(kn->kn_tq == &kq->kq_inprocess); + TAILQ_REMOVE(&kq->kq_inprocess, kn, kn_tqe); + kn->kn_tq = &kq->kq_head; + TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe); + } + if (kq->kq_state & KQ_PROCWAIT) { + kq->kq_state &= ~KQ_PROCWAIT; + thread_wakeup(&kq->kq_inprocess); + } + + *countp = nevents; + return error; +} + + +static void +kevent_scan_continue(void *data, wait_result_t wait_result) +{ + uthread_t ut = (uthread_t)get_bsdthread_info(current_thread()); + struct _kevent_scan * cont_args = &ut->uu_kevent.ss_kevent_scan; + struct kqueue *kq = (struct kqueue *)data; + int error; + int count; + + /* convert the (previous) wait_result to a proper error */ + switch (wait_result) { + case THREAD_AWAKENED: + kqlock(kq); + error = kevent_process(kq, cont_args->call, cont_args, &count, current_proc()); + if (error == 0 && count == 0) { + assert_wait_deadline(kq, THREAD_ABORTSAFE, cont_args->deadline); + kq->kq_state |= KQ_SLEEP; + kqunlock(kq); + thread_block_parameter(kevent_scan_continue, kq); + /* NOTREACHED */ + } + kqunlock(kq); + break; + case THREAD_TIMED_OUT: + error = EWOULDBLOCK; + break; + case THREAD_INTERRUPTED: + error = EINTR; + break; + default: + panic("kevent_scan_cont() - invalid wait_result (%d)", wait_result); + error = 0; + } + + /* call the continuation with the results */ + assert(cont_args->cont != NULL); + (cont_args->cont)(kq, cont_args->data, error); +} + + +/* + * kevent_scan - scan and wait for events in a kqueue + * + * Process the triggered events in a kqueue. + * + * If there are no events triggered arrange to + * wait for them. If the caller provided a + * continuation routine, then kevent_scan will + * also. + * + * The callback routine must be valid. + * The caller must hold a use-count reference on the kq. + */ + +int +kevent_scan(struct kqueue *kq, + kevent_callback_t callback, + kevent_continue_t continuation, + void *data, + struct timeval *atvp, + struct proc *p) +{ + thread_continue_t cont = THREAD_CONTINUE_NULL; + uint64_t deadline; + int error; + int first; + + assert(callback != NULL); + + first = 1; + for (;;) { + wait_result_t wait_result; + int count; + + /* + * Make a pass through the kq to find events already + * triggered. + */ + kqlock(kq); + error = kevent_process(kq, callback, data, &count, p); + if (error || count) + break; /* lock still held */ + + /* looks like we have to consider blocking */ + if (first) { + first = 0; + /* convert the timeout to a deadline once */ + if (atvp->tv_sec || atvp->tv_usec) { + uint64_t now; + + clock_get_uptime(&now); + nanoseconds_to_absolutetime((uint64_t)atvp->tv_sec * NSEC_PER_SEC + + atvp->tv_usec * NSEC_PER_USEC, + &deadline); + if (now >= deadline) { + /* non-blocking call */ + error = EWOULDBLOCK; + break; /* lock still held */ + } + deadline -= now; + clock_absolutetime_interval_to_deadline(deadline, &deadline); + } else { + deadline = 0; /* block forever */ + } + + if (continuation) { + uthread_t ut = (uthread_t)get_bsdthread_info(current_thread()); + struct _kevent_scan *cont_args = &ut->uu_kevent.ss_kevent_scan; + + cont_args->call = callback; + cont_args->cont = continuation; + cont_args->deadline = deadline; + cont_args->data = data; + cont = kevent_scan_continue; + } + } + + /* go ahead and wait */ + assert_wait_deadline(kq, THREAD_ABORTSAFE, deadline); + kq->kq_state |= KQ_SLEEP; + kqunlock(kq); + wait_result = thread_block_parameter(cont, kq); + /* NOTREACHED if (continuation != NULL) */ + + switch (wait_result) { + case THREAD_AWAKENED: + continue; + case THREAD_TIMED_OUT: + return EWOULDBLOCK; + case THREAD_INTERRUPTED: + return EINTR; + default: + panic("kevent_scan - bad wait_result (%d)", + wait_result); + error = 0; + } + } + kqunlock(kq); + return error; +} + + +/* + * XXX + * This could be expanded to call kqueue_scan, if desired. + */ +/*ARGSUSED*/ +static int +kqueue_read(__unused struct fileproc *fp, + __unused struct uio *uio, + __unused int flags, + __unused vfs_context_t ctx) +{ + return (ENXIO); +} + +/*ARGSUSED*/ +static int +kqueue_write(__unused struct fileproc *fp, + __unused struct uio *uio, + __unused int flags, + __unused vfs_context_t ctx) +{ + return (ENXIO); +} + +/*ARGSUSED*/ +static int +kqueue_ioctl(__unused struct fileproc *fp, + __unused u_long com, + __unused caddr_t data, + __unused vfs_context_t ctx) +{ + return (ENOTTY); +} + +/*ARGSUSED*/ +static int +kqueue_select(struct fileproc *fp, int which, void *wql, vfs_context_t ctx) +{ + struct kqueue *kq = (struct kqueue *)fp->f_data; + int retnum = 0; + + if (which == FREAD) { + kqlock(kq); + if (kq->kq_count) { + retnum = 1; + } else { + selrecord(vfs_context_proc(ctx), &kq->kq_sel, wql); + kq->kq_state |= KQ_SEL; + } + kqunlock(kq); + } + return (retnum); +} + +/* + * kqueue_close - + */ +/*ARGSUSED*/ +static int +kqueue_close(struct fileglob *fg, __unused vfs_context_t ctx) +{ + struct kqueue *kq = (struct kqueue *)fg->fg_data; + + kqueue_dealloc(kq); + fg->fg_data = NULL; + return (0); +} + +/*ARGSUSED*/ +/* + * The callers has taken a use-count reference on this kqueue and will donate it + * to the kqueue we are being added to. This keeps the kqueue from closing until + * that relationship is torn down. + */ +static int +kqueue_kqfilter(__unused struct fileproc *fp, struct knote *kn, __unused vfs_context_t ctx) +{ + struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data; + struct kqueue *parentkq = kn->kn_kq; + + if (parentkq == kq || + kn->kn_filter != EVFILT_READ) + return (1); + + /* + * We have to avoid creating a cycle when nesting kqueues + * inside another. Rather than trying to walk the whole + * potential DAG of nested kqueues, we just use a simple + * ceiling protocol. When a kqueue is inserted into another, + * we check that the (future) parent is not already nested + * into another kqueue at a lower level than the potenial + * child (because it could indicate a cycle). If that test + * passes, we just mark the nesting levels accordingly. + */ + + kqlock(parentkq); + if (parentkq->kq_level > 0 && + parentkq->kq_level < kq->kq_level) + { + kqunlock(parentkq); + return (1); + } else { + /* set parent level appropriately */ + if (parentkq->kq_level == 0) + parentkq->kq_level = 2; + if (parentkq->kq_level < kq->kq_level + 1) + parentkq->kq_level = kq->kq_level + 1; + kqunlock(parentkq); + + kn->kn_fop = &kqread_filtops; + kqlock(kq); + KNOTE_ATTACH(&kq->kq_sel.si_note, kn); + /* indicate nesting in child, if needed */ + if (kq->kq_level == 0) + kq->kq_level = 1; + kqunlock(kq); + return (0); + } +} + +/*ARGSUSED*/ +int +kqueue_stat(struct fileproc *fp, void *ub, int isstat64, __unused vfs_context_t ctx) +{ + struct stat *sb = (struct stat *)0; /* warning avoidance ; protected by isstat64 */ + struct stat64 * sb64 = (struct stat64 *)0; /* warning avoidance ; protected by isstat64 */ + + struct kqueue *kq = (struct kqueue *)fp->f_data; + if (isstat64 != 0) { + sb64 = (struct stat64 *)ub; + bzero((void *)sb64, sizeof(*sb64)); + sb64->st_size = kq->kq_count; + sb64->st_blksize = sizeof(struct kevent); + sb64->st_mode = S_IFIFO; + } else { + sb = (struct stat *)ub; + bzero((void *)sb, sizeof(*sb)); + sb->st_size = kq->kq_count; + sb->st_blksize = sizeof(struct kevent); + sb->st_mode = S_IFIFO; + } + + return (0); +} + +/* + * Called with the kqueue locked + */ +static void +kqueue_wakeup(struct kqueue *kq) +{ + + if (kq->kq_state & KQ_SLEEP) { + kq->kq_state &= ~KQ_SLEEP; + thread_wakeup(kq); + } + if (kq->kq_state & KQ_SEL) { + kq->kq_state &= ~KQ_SEL; + selwakeup(&kq->kq_sel); + } + KNOTE(&kq->kq_sel.si_note, 0); +} + +void +klist_init(struct klist *list) +{ + SLIST_INIT(list); +} + + +/* + * Query/Post each knote in the object's list + * + * The object lock protects the list. It is assumed + * that the filter/event routine for the object can + * determine that the object is already locked (via + * the hind) and not deadlock itself. + * + * The object lock should also hold off pending + * detach/drop operations. But we'll prevent it here + * too - just in case. + */ +void +knote(struct klist *list, long hint) +{ + struct knote *kn; + + SLIST_FOREACH(kn, list, kn_selnext) { + struct kqueue *kq = kn->kn_kq; + + kqlock(kq); + if (kqlock2knoteuse(kq, kn)) { + int result; + + /* call the event with only a use count */ + result = kn->kn_fop->f_event(kn, hint); + + /* if its not going away and triggered */ + if (knoteuse2kqlock(kq, kn) && result) + knote_activate(kn); + /* lock held again */ + } + kqunlock(kq); + } +} + +/* + * attach a knote to the specified list. Return true if this is the first entry. + * The list is protected by whatever lock the object it is associated with uses. + */ +int +knote_attach(struct klist *list, struct knote *kn) +{ + int ret = SLIST_EMPTY(list); + SLIST_INSERT_HEAD(list, kn, kn_selnext); + return ret; +} + +/* + * detach a knote from the specified list. Return true if that was the last entry. + * The list is protected by whatever lock the object it is associated with uses. + */ +int +knote_detach(struct klist *list, struct knote *kn) +{ + SLIST_REMOVE(list, kn, knote, kn_selnext); + return SLIST_EMPTY(list); +} + +/* + * remove all knotes referencing a specified fd + * + * Essentially an inlined knote_remove & knote_drop + * when we know for sure that the thing is a file + * + * Entered with the proc_fd lock already held. + * It returns the same way, but may drop it temporarily. + */ +void +knote_fdclose(struct proc *p, int fd) +{ + struct filedesc *fdp = p->p_fd; + struct klist *list; + struct knote *kn; + + list = &fdp->fd_knlist[fd]; + while ((kn = SLIST_FIRST(list)) != NULL) { + struct kqueue *kq = kn->kn_kq; + + if (kq->kq_p != p) + panic("knote_fdclose: proc mismatch (kq->kq_p=%p != p=%p)", kq->kq_p, p); + + kqlock(kq); + proc_fdunlock(p); + + /* + * Convert the lock to a drop ref. + * If we get it, go ahead and drop it. + * Otherwise, we waited for it to + * be dropped by the other guy, so + * it is safe to move on in the list. + */ + if (kqlock2knotedrop(kq, kn)) { + kn->kn_fop->f_detach(kn); + knote_drop(kn, p); + } + + proc_fdlock(p); + + /* the fd tables may have changed - start over */ + list = &fdp->fd_knlist[fd]; + } +} + +/* proc_fdlock held on entry (and exit) */ +static int +knote_fdpattach(struct knote *kn, struct filedesc *fdp, __unused struct proc *p) +{ + struct klist *list = NULL; + + if (! kn->kn_fop->f_isfd) { + if (fdp->fd_knhashmask == 0) + fdp->fd_knhash = hashinit(CONFIG_KN_HASHSIZE, M_KQUEUE, + &fdp->fd_knhashmask); + list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)]; + } else { + if ((u_int)fdp->fd_knlistsize <= kn->kn_id) { + u_int size = 0; + + /* have to grow the fd_knlist */ + size = fdp->fd_knlistsize; + while (size <= kn->kn_id) + size += KQEXTENT; + MALLOC(list, struct klist *, + size * sizeof(struct klist *), M_KQUEUE, M_WAITOK); + if (list == NULL) + return (ENOMEM); + + 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 *)); + FREE(fdp->fd_knlist, M_KQUEUE); + fdp->fd_knlist = list; + fdp->fd_knlistsize = size; + } + list = &fdp->fd_knlist[kn->kn_id]; + } + SLIST_INSERT_HEAD(list, kn, kn_link); + return (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, __unused struct proc *ctxp) +{ + struct kqueue *kq = kn->kn_kq; + struct proc *p = kq->kq_p; + struct filedesc *fdp = p->p_fd; + struct klist *list; + + proc_fdlock(p); + 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); + kqlock(kq); + knote_dequeue(kn); + if (kn->kn_status & KN_DROPWAIT) + thread_wakeup(&kn->kn_status); + kqunlock(kq); + proc_fdunlock(p); + + if (kn->kn_fop->f_isfd) + fp_drop(p, kn->kn_id, kn->kn_fp, 0); + + knote_free(kn); +} + +/* called with kqueue lock held */ +static void +knote_activate(struct knote *kn) +{ + struct kqueue *kq = kn->kn_kq; + + kn->kn_status |= KN_ACTIVE; + knote_enqueue(kn); + kqueue_wakeup(kq); + } + +/* called with kqueue lock held */ +static void +knote_deactivate(struct knote *kn) +{ + kn->kn_status &= ~KN_ACTIVE; + knote_dequeue(kn); +} + +/* called with kqueue lock held */ +static void +knote_enqueue(struct knote *kn) +{ + struct kqueue *kq = kn->kn_kq; + + if ((kn->kn_status & (KN_QUEUED | KN_DISABLED)) == 0) { + struct kqtailq *tq = kn->kn_tq; + + TAILQ_INSERT_TAIL(tq, kn, kn_tqe); + kn->kn_status |= KN_QUEUED; + kq->kq_count++; + } +} + +/* called with kqueue lock held */ +static void +knote_dequeue(struct knote *kn) +{ + struct kqueue *kq = kn->kn_kq; + + //assert((kn->kn_status & KN_DISABLED) == 0); + if ((kn->kn_status & KN_QUEUED) == KN_QUEUED) { + struct kqtailq *tq = kn->kn_tq; + + TAILQ_REMOVE(tq, kn, kn_tqe); + kn->kn_tq = &kq->kq_head; + kn->kn_status &= ~KN_QUEUED; + kq->kq_count--; + } +} + +void +knote_init(void) +{ + knote_zone = zinit(sizeof(struct knote), 8192*sizeof(struct knote), 8192, "knote zone"); + + /* allocate kq lock group attribute and group */ + kq_lck_grp_attr= lck_grp_attr_alloc_init(); + + kq_lck_grp = lck_grp_alloc_init("kqueue", kq_lck_grp_attr); + + /* Allocate kq lock attribute */ + kq_lck_attr = lck_attr_alloc_init(); + + /* Initialize the timer filter lock */ + lck_mtx_init(&_filt_timerlock, kq_lck_grp, kq_lck_attr); +} +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); +} + +#if SOCKETS #include #include #include @@ -38,8 +2016,17 @@ #include -int raw_usrreq(); -struct pr_usrreqs event_usrreqs; +static int kev_attach(struct socket *so, int proto, struct proc *p); +static int kev_detach(struct socket *so); +static int kev_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp, struct proc *p); + +struct pr_usrreqs event_usrreqs = { + pru_abort_notsupp, pru_accept_notsupp, kev_attach, pru_bind_notsupp, pru_connect_notsupp, + pru_connect2_notsupp, kev_control, kev_detach, pru_disconnect_notsupp, + pru_listen_notsupp, pru_peeraddr_notsupp, pru_rcvd_notsupp, pru_rcvoob_notsupp, + pru_send_notsupp, pru_sense_null, pru_shutdown_notsupp, pru_sockaddr_notsupp, + pru_sosend_notsupp, soreceive, pru_sopoll_notsupp +}; struct protosw eventsw[] = { { @@ -47,7 +2034,14 @@ struct protosw eventsw[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, &event_usrreqs +#if __APPLE__ + 0, +#endif + &event_usrreqs, + 0, 0, 0, +#if __APPLE__ + {0, 0}, 0, {0} +#endif } }; @@ -55,6 +2049,8 @@ static struct kern_event_head kern_event_head; static u_long static_event_id = 0; +struct domain *sysdom = &systemdomain; +static lck_mtx_t *sys_mtx; /* * Install the protosw's for the NKE manager. Invoked at @@ -65,19 +2061,30 @@ kern_event_init(void) { int retval; - if ((retval = net_add_proto(eventsw, &systemdomain)) == 0) - return(KERN_SUCCESS); - - log(LOG_WARNING, "Can't install kernel events protocol (%d)\n", retval); - return(retval); + if ((retval = net_add_proto(eventsw, &systemdomain)) != 0) { + log(LOG_WARNING, "Can't install kernel events protocol (%d)\n", retval); + return(retval); + } + + /* + * Use the domain mutex for all system event sockets + */ + sys_mtx = sysdom->dom_mtx; + + return(KERN_SUCCESS); } -int kev_attach(struct socket *so, int proto, struct proc *p) +static int +kev_attach(struct socket *so, __unused int proto, __unused struct proc *p) { int error; struct kern_event_pcb *ev_pcb; - ev_pcb = _MALLOC(sizeof(struct kern_event_pcb), M_PCB, M_WAITOK); + error = soreserve(so, KEV_SNDSPACE, KEV_RECVSPACE); + if (error) + return error; + + MALLOC(ev_pcb, struct kern_event_pcb *, sizeof(struct kern_event_pcb), M_PCB, M_WAITOK); if (ev_pcb == 0) return ENOBUFS; @@ -85,26 +2092,63 @@ int kev_attach(struct socket *so, int proto, struct proc *p) ev_pcb->vendor_code_filter = 0xffffffff; so->so_pcb = (caddr_t) ev_pcb; + lck_mtx_lock(sys_mtx); LIST_INSERT_HEAD(&kern_event_head, ev_pcb, ev_link); - error = soreserve(so, KEV_SNDSPACE, KEV_RECVSPACE); - if (error) - return error; + lck_mtx_unlock(sys_mtx); return 0; } -int kev_detach(struct socket *so) +static int +kev_detach(struct socket *so) { struct kern_event_pcb *ev_pcb = (struct kern_event_pcb *) so->so_pcb; - LIST_REMOVE(ev_pcb, ev_link); - if (ev_pcb) - FREE(ev_pcb, M_PCB); + if (ev_pcb != 0) { + LIST_REMOVE(ev_pcb, ev_link); + FREE(ev_pcb, M_PCB); + so->so_pcb = 0; + so->so_flags |= SOF_PCBCLEARING; + } return 0; } +/* + * For now, kev_vendor_code and mbuf_tags use the same + * mechanism. + */ + +errno_t kev_vendor_code_find( + const char *string, + u_int32_t *out_vendor_code) +{ + if (strlen(string) >= KEV_VENDOR_CODE_MAX_STR_LEN) { + return EINVAL; + } + return mbuf_tag_id_find_internal(string, out_vendor_code, 1); +} + +errno_t kev_msg_post(struct kev_msg *event_msg) +{ + mbuf_tag_id_t min_vendor, max_vendor; + + mbuf_tag_id_first_last(&min_vendor, &max_vendor); + + if (event_msg == NULL) + return EINVAL; + + /* Limit third parties to posting events for registered vendor codes only */ + if (event_msg->vendor_code < min_vendor || + event_msg->vendor_code > max_vendor) + { + return EINVAL; + } + + return kev_post_msg(event_msg); +} + int kev_post_msg(struct kev_msg *event_msg) { @@ -112,9 +2156,21 @@ int kev_post_msg(struct kev_msg *event_msg) struct kern_event_pcb *ev_pcb; struct kern_event_msg *ev; char *tmp; - int total_size; + unsigned long total_size; int i; + /* Verify the message is small enough to fit in one mbuf w/o cluster */ + total_size = KEV_MSG_HEADER_SIZE; + + for (i = 0; i < 5; i++) { + if (event_msg->dv[i].data_length == 0) + break; + total_size += event_msg->dv[i].data_length; + } + + if (total_size > MLEN) { + return EMSGSIZE; + } m = m_get(M_DONTWAIT, MT_DATA); if (m == 0) @@ -134,7 +2190,6 @@ int kev_post_msg(struct kev_msg *event_msg) tmp += event_msg->dv[i].data_length; } - ev->id = ++static_event_id; ev->total_size = total_size; ev->vendor_code = event_msg->vendor_code; @@ -143,6 +2198,7 @@ int kev_post_msg(struct kev_msg *event_msg) ev->event_code = event_msg->event_code; m->m_len = total_size; + lck_mtx_lock(sys_mtx); for (ev_pcb = LIST_FIRST(&kern_event_head); ev_pcb; ev_pcb = LIST_NEXT(ev_pcb, ev_link)) { @@ -164,67 +2220,88 @@ int kev_post_msg(struct kev_msg *event_msg) m2 = m_copym(m, 0, m->m_len, M_NOWAIT); if (m2 == 0) { m_free(m); + lck_mtx_unlock(sys_mtx); return ENOBUFS; } - - sbappendrecord(&ev_pcb->ev_socket->so_rcv, m2); - sorwakeup(ev_pcb->ev_socket); + /* the socket is already locked because we hold the sys_mtx here */ + if (sbappendrecord(&ev_pcb->ev_socket->so_rcv, m2)) + sorwakeup(ev_pcb->ev_socket); } - m_free(m); + lck_mtx_unlock(sys_mtx); return 0; } - -int kev_control(so, cmd, data, ifp, p) - struct socket *so; - u_long cmd; - caddr_t data; - register struct ifnet *ifp; - struct proc *p; +static int +kev_control(struct socket *so, + u_long cmd, + caddr_t data, + __unused struct ifnet *ifp, + __unused struct proc *p) { - struct kev_request *kev_req = (struct kev_request *) data; - int stat = 0; - struct kern_event_pcb *ev_pcb; - u_long *id_value = (u_long *) data; - + struct kev_request *kev_req = (struct kev_request *) data; + struct kern_event_pcb *ev_pcb; + struct kev_vendor_code *kev_vendor; + u_long *id_value = (u_long *) data; + + + switch (cmd) { + + case SIOCGKEVID: + *id_value = static_event_id; + break; + + case SIOCSKEVFILT: + ev_pcb = (struct kern_event_pcb *) so->so_pcb; + ev_pcb->vendor_code_filter = kev_req->vendor_code; + ev_pcb->class_filter = kev_req->kev_class; + ev_pcb->subclass_filter = kev_req->kev_subclass; + break; + + case SIOCGKEVFILT: + ev_pcb = (struct kern_event_pcb *) so->so_pcb; + kev_req->vendor_code = ev_pcb->vendor_code_filter; + kev_req->kev_class = ev_pcb->class_filter; + kev_req->kev_subclass = ev_pcb->subclass_filter; + break; + + case SIOCGKEVVENDOR: + kev_vendor = (struct kev_vendor_code*)data; + + /* Make sure string is NULL terminated */ + kev_vendor->vendor_string[KEV_VENDOR_CODE_MAX_STR_LEN-1] = 0; + + return mbuf_tag_id_find_internal(kev_vendor->vendor_string, + &kev_vendor->vendor_code, 0); + + default: + return ENOTSUP; + } + + return 0; +} - switch (cmd) { +#endif /* SOCKETS */ - case SIOCGKEVID: - *id_value = static_event_id; - break; - case SIOCSKEVFILT: - ev_pcb = (struct kern_event_pcb *) so->so_pcb; - ev_pcb->vendor_code_filter = kev_req->vendor_code; - ev_pcb->class_filter = kev_req->kev_class; - ev_pcb->subclass_filter = kev_req->kev_subclass; - break; +int +fill_kqueueinfo(struct kqueue *kq, struct kqueue_info * kinfo) +{ + struct vinfo_stat * st; - case SIOCGKEVFILT: - ev_pcb = (struct kern_event_pcb *) so->so_pcb; - kev_req->vendor_code = ev_pcb->vendor_code_filter; - kev_req->kev_class = ev_pcb->class_filter; - kev_req->kev_subclass = ev_pcb->subclass_filter; - break; + /* No need for the funnel as fd is kept alive */ + + st = &kinfo->kq_stat; - default: - return EOPNOTSUPP; - } + st->vst_size = kq->kq_count; + st->vst_blksize = sizeof(struct kevent); + st->vst_mode = S_IFIFO; + if (kq->kq_state & KQ_SEL) + kinfo->kq_state |= PROC_KQUEUE_SELECT; + if (kq->kq_state & KQ_SLEEP) + kinfo->kq_state |= PROC_KQUEUE_SLEEP; - return 0; + return(0); } - -struct pr_usrreqs event_usrreqs = { - pru_abort_notsupp, pru_accept_notsupp, kev_attach, pru_bind_notsupp, pru_connect_notsupp, - pru_connect2_notsupp, kev_control, kev_detach, pru_disconnect_notsupp, - pru_listen_notsupp, pru_peeraddr_notsupp, pru_rcvd_notsupp, pru_rcvoob_notsupp, - pru_send_notsupp, pru_sense_null, pru_shutdown_notsupp, pru_sockaddr_notsupp, - pru_sosend_notsupp, soreceive, sopoll -}; - - -