1 /*
2  * Copyright (c) 2006 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/systimer.h>
39 #include <sys/sysctl.h>
40 #include <sys/signal.h>
41 #include <sys/interrupt.h>
42 #include <sys/bus.h>
43 #include <sys/time.h>
44 #include <sys/event.h>
45 #include <machine/cpu.h>
46 #include <machine/globaldata.h>
47 #include <machine/md_var.h>
48 
49 #include <sys/thread2.h>
50 
51 #include <unistd.h>
52 #include <signal.h>
53 #include <stdlib.h>
54 #include <fcntl.h>
55 
56 struct kqueue_info {
57 	void (*func)(void *, struct intrframe *);
58 	void *data;
59 	int fd;
60 };
61 
62 static int KQueueFd = -1;
63 
64 /*
65  * Initialize kqueue based I/O
66  *
67  * Use SIGIO to get an immediate event when the kqueue has something waiting
68  * for us.  Setup the SIGIO signal as a mailbox signal for efficiency.
69  *
70  * Currently only read events are supported.
71  */
72 void
73 init_kqueue(void)
74 {
75 #if 0
76 	struct sigaction sa;
77 	bzero(&sa, sizeof(sa));
78 	/*sa.sa_mailbox = &mdcpu->gd_mailbox;*/
79 	sa.sa_flags = 0;
80 	sa.sa_handler = kqueuesig;
81 	sigemptyset(&sa.sa_mask);
82 	sigaction(SIGIO, &sa, NULL);
83 #endif
84 	KQueueFd = kqueue();
85 	if (fcntl(KQueueFd, F_SETOWN, getpid()) < 0)
86 		panic("Cannot configure kqueue for SIGIO, update your kernel");
87 	if (fcntl(KQueueFd, F_SETFL, O_ASYNC) < 0)
88 		panic("Cannot configure kqueue for SIGIO, update your kernel");
89 }
90 
91 #if 0
92 /*
93  * Signal handler dispatches interrupt thread.  Use interrupt #1
94  */
95 static void
96 kqueuesig(int signo)
97 {
98 	signalintr(1);
99 }
100 
101 #endif
102 
103 /*
104  * Generic I/O event support
105  */
106 struct kqueue_info *
107 kqueue_add(int fd, void (*func)(void *, struct intrframe *), void *data)
108 {
109 	struct timespec ts = { 0, 0 };
110 	struct kqueue_info *info;
111 	struct kevent kev;
112 
113 	info = kmalloc(sizeof(*info), M_DEVBUF, M_ZERO|M_INTWAIT);
114 	info->func = func;
115 	info->data = data;
116 	info->fd = fd;
117 	EV_SET(&kev, fd, EVFILT_READ, EV_ADD|EV_ENABLE|EV_CLEAR, 0, 0, info);
118 	if (kevent(KQueueFd, &kev, 1, NULL, 0, &ts) < 0)
119 		panic("kqueue: kevent() call could not add descriptor");
120 	return(info);
121 }
122 
123 #if 0
124 /*
125  * Medium resolution timer support
126  */
127 struct kqueue_info *
128 kqueue_add_timer(void (*func)(void *, struct intrframe *), void *data)
129 {
130 	struct kqueue_info *info;
131 
132 	info = kmalloc(sizeof(*info), M_DEVBUF, M_ZERO|M_INTWAIT);
133 	info->func = func;
134 	info->data = data;
135 	info->fd = (uintptr_t)info;
136 
137 	return(info);
138 }
139 
140 void
141 kqueue_reload_timer(struct kqueue_info *info, int ms)
142 {
143 	struct timespec ts = { 0, 0 };
144 	struct kevent kev;
145 
146 	KKASSERT(ms > 0);
147 
148 	EV_SET(&kev, info->fd, EVFILT_TIMER,
149 		EV_ADD|EV_ENABLE|EV_ONESHOT|EV_CLEAR, 0, (uintptr_t)ms, info);
150 	if (kevent(KQueueFd, &kev, 1, NULL, 0, &ts) < 0)
151 		panic("kqueue_reload_timer: Failed");
152 }
153 #endif
154 
155 /*
156  * Destroy a previously added kqueue event
157  */
158 void
159 kqueue_del(struct kqueue_info *info)
160 {
161 	struct timespec ts = { 0, 0 };
162 	struct kevent kev;
163 
164 	KKASSERT(info->fd >= 0);
165 	EV_SET(&kev, info->fd, EVFILT_READ, EV_DELETE, 0, 0, NULL);
166 	if (kevent(KQueueFd, &kev, 1, NULL, 0, &ts) < 0)
167 		panic("kevent: failed to delete descriptor %d", info->fd);
168 	info->fd = -1;
169 	kfree(info, M_DEVBUF);
170 }
171 
172 /*
173  * Safely called via DragonFly's normal interrupt handling mechanism.
174  *
175  * Calleld with the MP lock held.  Note that this is still an interrupt
176  * thread context.
177  */
178 void
179 kqueue_intr(struct intrframe *frame)
180 {
181 	struct timespec ts;
182 	struct kevent kevary[8];
183 	int n;
184 	int i;
185 
186 	ts.tv_sec = 0;
187 	ts.tv_nsec = 0;
188 	do {
189 		n = kevent(KQueueFd, NULL, 0, kevary, 8, &ts);
190 		for (i = 0; i < n; ++i) {
191 			struct kevent *kev = &kevary[i];
192 			struct kqueue_info *info = (void *)kev->udata;
193 
194 			info->func(info->data, frame);
195 		}
196 	} while (n == 8);
197 }
198