/* * Copyright (c) 2000-2006 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. 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 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @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 #include #include #include #include #include #include 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[] = { { SOCK_RAW, &systemdomain, SYSPROTO_EVENT, PR_ATOMIC, 0, 0, 0, 0, 0, 0, 0, 0, 0, #if __APPLE__ 0, #endif &event_usrreqs, 0, 0, 0, #if __APPLE__ {0, 0}, 0, {0} #endif } }; 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 * extension load time */ int kern_event_init(void) { int 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); } static int kev_attach(struct socket *so, __unused int proto, __unused struct proc *p) { int error; struct kern_event_pcb *ev_pcb; 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; ev_pcb->ev_socket = so; 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); lck_mtx_unlock(sys_mtx); return 0; } static int kev_detach(struct socket *so) { struct kern_event_pcb *ev_pcb = (struct kern_event_pcb *) so->so_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) { struct mbuf *m, *m2; struct kern_event_pcb *ev_pcb; struct kern_event_msg *ev; char *tmp; 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) return ENOBUFS; ev = mtod(m, struct kern_event_msg *); total_size = KEV_MSG_HEADER_SIZE; tmp = (char *) &ev->event_data[0]; for (i = 0; i < 5; i++) { if (event_msg->dv[i].data_length == 0) break; total_size += event_msg->dv[i].data_length; bcopy(event_msg->dv[i].data_ptr, tmp, event_msg->dv[i].data_length); tmp += event_msg->dv[i].data_length; } ev->id = ++static_event_id; ev->total_size = total_size; ev->vendor_code = event_msg->vendor_code; ev->kev_class = event_msg->kev_class; ev->kev_subclass = event_msg->kev_subclass; 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)) { if (ev_pcb->vendor_code_filter != KEV_ANY_VENDOR) { if (ev_pcb->vendor_code_filter != ev->vendor_code) continue; if (ev_pcb->class_filter != KEV_ANY_CLASS) { if (ev_pcb->class_filter != ev->kev_class) continue; if ((ev_pcb->subclass_filter != KEV_ANY_SUBCLASS) && (ev_pcb->subclass_filter != ev->kev_subclass)) continue; } } m2 = m_copym(m, 0, m->m_len, M_NOWAIT); if (m2 == 0) { m_free(m); lck_mtx_unlock(sys_mtx); return ENOBUFS; } /* 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; } 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; 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; } #endif /* SOCKETS */ int fill_kqueueinfo(struct kqueue *kq, struct kqueue_info * kinfo) { struct vinfo_stat * st; /* No need for the funnel as fd is kept alive */ st = &kinfo->kq_stat; 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); }