1/*-
2 * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29#ifndef _SYS_EVENT_H_
30#define _SYS_EVENT_H_
31
32#include <sys/queue.h>
33
34#define EVFILT_READ		(-1)
35#define EVFILT_WRITE		(-2)
36#define EVFILT_AIO		(-3)	/* attached to aio requests */
37#define EVFILT_VNODE		(-4)	/* attached to vnodes */
38#define EVFILT_PROC		(-5)	/* attached to struct proc */
39#define EVFILT_SIGNAL		(-6)	/* attached to struct proc */
40#define EVFILT_TIMER		(-7)	/* timers */
41/*	EVFILT_NETDEV		(-8)	   no longer supported */
42#define EVFILT_FS		(-9)	/* filesystem events */
43#define EVFILT_LIO		(-10)	/* attached to lio requests */
44#define EVFILT_USER		(-11)	/* User events */
45#define EVFILT_SYSCOUNT		11
46
47#define EV_SET(kevp_, a, b, c, d, e, f) do {	\
48	struct kevent *kevp = (kevp_);		\
49	(kevp)->ident = (a);			\
50	(kevp)->filter = (b);			\
51	(kevp)->flags = (c);			\
52	(kevp)->fflags = (d);			\
53	(kevp)->data = (e);			\
54	(kevp)->udata = (f);			\
55} while(0)
56
57struct kevent {
58	uintptr_t	ident;		/* identifier for this event */
59	short		filter;		/* filter for event */
60	u_short		flags;
61	u_int		fflags;
62	intptr_t	data;
63	void		*udata;		/* opaque user data identifier */
64};
65
66/* actions */
67#define EV_ADD		0x0001		/* add event to kq (implies enable) */
68#define EV_DELETE	0x0002		/* delete event from kq */
69#define EV_ENABLE	0x0004		/* enable event */
70#define EV_DISABLE	0x0008		/* disable event (not reported) */
71
72/* flags */
73#define EV_ONESHOT	0x0010		/* only report one occurrence */
74#define EV_CLEAR	0x0020		/* clear event state after reporting */
75#define EV_RECEIPT	0x0040		/* force EV_ERROR on success, data=0 */
76#define EV_DISPATCH	0x0080		/* disable event after reporting */
77
78#define EV_SYSFLAGS	0xF000		/* reserved by system */
79#define	EV_DROP		0x1000		/* note should be dropped */
80#define EV_FLAG1	0x2000		/* filter-specific flag */
81
82/* returned values */
83#define EV_EOF		0x8000		/* EOF detected */
84#define EV_ERROR	0x4000		/* error, data contains errno */
85
86 /*
87  * data/hint flags/masks for EVFILT_USER, shared with userspace
88  *
89  * On input, the top two bits of fflags specifies how the lower twenty four
90  * bits should be applied to the stored value of fflags.
91  *
92  * On output, the top two bits will always be set to NOTE_FFNOP and the
93  * remaining twenty four bits will contain the stored fflags value.
94  */
95#define NOTE_FFNOP	0x00000000		/* ignore input fflags */
96#define NOTE_FFAND	0x40000000		/* AND fflags */
97#define NOTE_FFOR	0x80000000		/* OR fflags */
98#define NOTE_FFCOPY	0xc0000000		/* copy fflags */
99#define NOTE_FFCTRLMASK	0xc0000000		/* masks for operations */
100#define NOTE_FFLAGSMASK	0x00ffffff
101
102#define NOTE_TRIGGER	0x01000000		/* Cause the event to be
103						   triggered for output. */
104
105/*
106 * data/hint flags for EVFILT_{READ|WRITE}, shared with userspace
107 */
108#define NOTE_LOWAT	0x0001			/* low water mark */
109
110/*
111 * data/hint flags for EVFILT_VNODE, shared with userspace
112 */
113#define	NOTE_DELETE	0x0001			/* vnode was removed */
114#define	NOTE_WRITE	0x0002			/* data contents changed */
115#define	NOTE_EXTEND	0x0004			/* size increased */
116#define	NOTE_ATTRIB	0x0008			/* attributes changed */
117#define	NOTE_LINK	0x0010			/* link count changed */
118#define	NOTE_RENAME	0x0020			/* vnode was renamed */
119#define	NOTE_REVOKE	0x0040			/* vnode access was revoked */
120
121/*
122 * data/hint flags for EVFILT_PROC, shared with userspace
123 */
124#define	NOTE_EXIT	0x80000000		/* process exited */
125#define	NOTE_FORK	0x40000000		/* process forked */
126#define	NOTE_EXEC	0x20000000		/* process exec'd */
127#define	NOTE_PCTRLMASK	0xf0000000		/* mask for hint bits */
128#define	NOTE_PDATAMASK	0x000fffff		/* mask for pid */
129
130/* additional flags for EVFILT_PROC */
131#define	NOTE_TRACK	0x00000001		/* follow across forks */
132#define	NOTE_TRACKERR	0x00000002		/* could not track child */
133#define	NOTE_CHILD	0x00000004		/* am a child process */
134
135struct knote;
136SLIST_HEAD(klist, knote);
137struct kqueue;
138TAILQ_HEAD(kqlist, kqueue);
139struct knlist {
140	struct	klist	kl_list;
141	void    (*kl_lock)(void *);	/* lock function */
142	void    (*kl_unlock)(void *);
143	void	(*kl_assert_locked)(void *);
144	void	(*kl_assert_unlocked)(void *);
145	void *kl_lockarg;		/* argument passed to kl_lockf() */
146};
147
148
149#ifdef _KERNEL
150
151/*
152 * Flags for knote call
153 */
154#define	KNF_LISTLOCKED	0x0001			/* knlist is locked */
155#define	KNF_NOKQLOCK	0x0002			/* do not keep KQ_LOCK */
156
157#define KNOTE(list, hist, flags)	knote(list, hist, flags)
158#define KNOTE_LOCKED(list, hint)	knote(list, hint, KNF_LISTLOCKED)
159#define KNOTE_UNLOCKED(list, hint)	knote(list, hint, 0)
160
161#define	KNLIST_EMPTY(list)		SLIST_EMPTY(&(list)->kl_list)
162
163/*
164 * Flag indicating hint is a signal.  Used by EVFILT_SIGNAL, and also
165 * shared by EVFILT_PROC  (all knotes attached to p->p_klist)
166 */
167#define NOTE_SIGNAL	0x08000000
168
169/*
170 * Hint values for the optional f_touch event filter.  If f_touch is not set
171 * to NULL and f_isfd is zero the f_touch filter will be called with the type
172 * argument set to EVENT_REGISTER during a kevent() system call.  It is also
173 * called under the same conditions with the type argument set to EVENT_PROCESS
174 * when the event has been triggered.
175 */
176#define EVENT_REGISTER	1
177#define EVENT_PROCESS	2
178
179struct filterops {
180	int	f_isfd;		/* true if ident == filedescriptor */
181	int	(*f_attach)(struct knote *kn);
182	void	(*f_detach)(struct knote *kn);
183	int	(*f_event)(struct knote *kn, long hint);
184	void	(*f_touch)(struct knote *kn, struct kevent *kev, u_long type);
185};
186
187/*
188 * Setting the KN_INFLUX flag enables you to unlock the kq that this knote
189 * is on, and modify kn_status as if you had the KQ lock.
190 *
191 * kn_sfflags, kn_sdata, and kn_kevent are protected by the knlist lock.
192 */
193struct knote {
194	SLIST_ENTRY(knote)	kn_link;	/* for kq */
195	SLIST_ENTRY(knote)	kn_selnext;	/* for struct selinfo */
196	struct			knlist *kn_knlist;	/* f_attach populated */
197	TAILQ_ENTRY(knote)	kn_tqe;
198	struct			kqueue *kn_kq;	/* which queue we are on */
199	struct 			kevent kn_kevent;
200	int			kn_status;	/* protected by kq lock */
201#define KN_ACTIVE	0x01			/* event has been triggered */
202#define KN_QUEUED	0x02			/* event is on queue */
203#define KN_DISABLED	0x04			/* event is disabled */
204#define KN_DETACHED	0x08			/* knote is detached */
205#define KN_INFLUX	0x10			/* knote is in flux */
206#define KN_MARKER	0x20			/* ignore this knote */
207#define KN_KQUEUE	0x40			/* this knote belongs to a kq */
208#define KN_HASKQLOCK	0x80			/* for _inevent */
209#define	KN_SCAN		0x100			/* flux set in kqueue_scan() */
210	int			kn_sfflags;	/* saved filter flags */
211	intptr_t		kn_sdata;	/* saved data field */
212	union {
213		struct		file *p_fp;	/* file data pointer */
214		struct		proc *p_proc;	/* proc pointer */
215		struct		aiocblist *p_aio;	/* AIO job pointer */
216		struct		aioliojob *p_lio;	/* LIO job pointer */
217	} kn_ptr;
218	struct			filterops *kn_fop;
219	void			*kn_hook;
220	int			kn_hookid;
221
222#define kn_id		kn_kevent.ident
223#define kn_filter	kn_kevent.filter
224#define kn_flags	kn_kevent.flags
225#define kn_fflags	kn_kevent.fflags
226#define kn_data		kn_kevent.data
227#define kn_fp		kn_ptr.p_fp
228};
229struct kevent_copyops {
230	void	*arg;
231	int	(*k_copyout)(void *arg, struct kevent *kevp, int count);
232	int	(*k_copyin)(void *arg, struct kevent *kevp, int count);
233};
234
235struct thread;
236struct proc;
237struct knlist;
238struct mtx;
239struct rwlock;
240
241extern void	knote(struct knlist *list, long hint, int lockflags);
242extern void	knote_fork(struct knlist *list, int pid);
243extern void	knlist_add(struct knlist *knl, struct knote *kn, int islocked);
244extern void	knlist_remove(struct knlist *knl, struct knote *kn, int islocked);
245extern void	knlist_remove_inevent(struct knlist *knl, struct knote *kn);
246extern int	knlist_empty(struct knlist *knl);
247extern void	knlist_init(struct knlist *knl, void *lock,
248    void (*kl_lock)(void *), void (*kl_unlock)(void *),
249    void (*kl_assert_locked)(void *), void (*kl_assert_unlocked)(void *));
250extern void	knlist_init_mtx(struct knlist *knl, struct mtx *lock);
251extern void	knlist_init_rw_reader(struct knlist *knl, struct rwlock *lock);
252extern void	knlist_destroy(struct knlist *knl);
253extern void	knlist_cleardel(struct knlist *knl, struct thread *td,
254	int islocked, int killkn);
255#define knlist_clear(knl, islocked)				\
256		knlist_cleardel((knl), NULL, (islocked), 0)
257#define knlist_delete(knl, td, islocked)			\
258		knlist_cleardel((knl), (td), (islocked), 1)
259extern void	knote_fdclose(struct thread *p, int fd);
260extern int 	kqfd_register(int fd, struct kevent *kev, struct thread *p,
261		    int waitok);
262extern int	kqueue_add_filteropts(int filt, struct filterops *filtops);
263extern int	kqueue_del_filteropts(int filt);
264
265#else 	/* !_KERNEL */
266
267#include <sys/cdefs.h>
268struct timespec;
269
270__BEGIN_DECLS
271int     kqueue(void);
272int     kevent(int kq, const struct kevent *changelist, int nchanges,
273	    struct kevent *eventlist, int nevents,
274	    const struct timespec *timeout);
275__END_DECLS
276
277#endif /* !_KERNEL */
278
279#endif /* !_SYS_EVENT_H_ */
280