xref: /freebsd/sys/kern/subr_autoconf.c (revision 77a62bf55d9fa10d6376ee53c1ddd9790dd41d36)
1 /*-
2  * Copyright (c) 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This software was developed by the Computer Systems Engineering group
6  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7  * contributed to Berkeley.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)subr_autoconf.c	8.1 (Berkeley) 6/10/93
34  *
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include "opt_ddb.h"
41 
42 #include <sys/param.h>
43 #include <sys/kernel.h>
44 #include <sys/linker.h>
45 #include <sys/lock.h>
46 #include <sys/mutex.h>
47 #include <sys/systm.h>
48 
49 /*
50  * Autoconfiguration subroutines.
51  */
52 
53 /*
54  * "Interrupt driven config" functions.
55  */
56 static TAILQ_HEAD(, intr_config_hook) intr_config_hook_list =
57 	TAILQ_HEAD_INITIALIZER(intr_config_hook_list);
58 static struct mtx intr_config_hook_lock;
59 MTX_SYSINIT(intr_config_hook, &intr_config_hook_lock, "intr config", MTX_DEF);
60 
61 /* ARGSUSED */
62 static void run_interrupt_driven_config_hooks(void *dummy);
63 
64 /*
65  * If we wait too long for an interrupt-driven config hook to return, print
66  * a diagnostic.
67  */
68 #define	WARNING_INTERVAL_SECS	60
69 static void
70 run_interrupt_driven_config_hooks_warning(int warned)
71 {
72 	struct intr_config_hook *hook_entry;
73 	char namebuf[64];
74 	long offset;
75 
76 	if (warned < 6) {
77 		printf("run_interrupt_driven_hooks: still waiting after %d "
78 		    "seconds for", warned * WARNING_INTERVAL_SECS);
79 		TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) {
80 			if (linker_search_symbol_name(
81 			    (caddr_t)hook_entry->ich_func, namebuf,
82 			    sizeof(namebuf), &offset) == 0)
83 				printf(" %s", namebuf);
84 			else
85 				printf(" %p", hook_entry->ich_func);
86 		}
87 		printf("\n");
88 	}
89 	KASSERT(warned < 6,
90 	    ("run_interrupt_driven_config_hooks: waited too long"));
91 }
92 
93 static void
94 run_interrupt_driven_config_hooks(dummy)
95 	void *dummy;
96 {
97 	struct intr_config_hook *hook_entry, *next_entry;
98 	int warned;
99 
100 	mtx_lock(&intr_config_hook_lock);
101 	TAILQ_FOREACH_SAFE(hook_entry, &intr_config_hook_list, ich_links,
102 	    next_entry) {
103 		mtx_unlock(&intr_config_hook_lock);
104 		(*hook_entry->ich_func)(hook_entry->ich_arg);
105 		mtx_lock(&intr_config_hook_lock);
106 	}
107 
108 	warned = 0;
109 	while (!TAILQ_EMPTY(&intr_config_hook_list)) {
110 		if (msleep(&intr_config_hook_list, &intr_config_hook_lock,
111 		    PCONFIG, "conifhk", WARNING_INTERVAL_SECS * hz) ==
112 		    EWOULDBLOCK) {
113 			mtx_unlock(&intr_config_hook_lock);
114 			warned++;
115 			run_interrupt_driven_config_hooks_warning(warned);
116 			mtx_lock(&intr_config_hook_lock);
117 		}
118 	}
119 	mtx_unlock(&intr_config_hook_lock);
120 }
121 SYSINIT(intr_config_hooks, SI_SUB_INT_CONFIG_HOOKS, SI_ORDER_FIRST,
122 	run_interrupt_driven_config_hooks, NULL);
123 
124 /*
125  * Register a hook that will be called after "cold"
126  * autoconfiguration is complete and interrupts can
127  * be used to complete initialization.
128  */
129 int
130 config_intrhook_establish(hook)
131 	struct intr_config_hook *hook;
132 {
133 	struct intr_config_hook *hook_entry;
134 
135 	mtx_lock(&intr_config_hook_lock);
136 	TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links)
137 		if (hook_entry == hook)
138 			break;
139 	if (hook_entry != NULL) {
140 		mtx_unlock(&intr_config_hook_lock);
141 		printf("config_intrhook_establish: establishing an "
142 		       "already established hook.\n");
143 		return (1);
144 	}
145 	TAILQ_INSERT_TAIL(&intr_config_hook_list, hook, ich_links);
146 	mtx_unlock(&intr_config_hook_lock);
147 	if (cold == 0)
148 		/* XXX Sufficient for modules loaded after initial config??? */
149 		run_interrupt_driven_config_hooks(NULL);
150 	return (0);
151 }
152 
153 void
154 config_intrhook_disestablish(hook)
155 	struct intr_config_hook *hook;
156 {
157 	struct intr_config_hook *hook_entry;
158 
159 	mtx_lock(&intr_config_hook_lock);
160 	TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links)
161 		if (hook_entry == hook)
162 			break;
163 	if (hook_entry == NULL)
164 		panic("config_intrhook_disestablish: disestablishing an "
165 		      "unestablished hook");
166 
167 	TAILQ_REMOVE(&intr_config_hook_list, hook, ich_links);
168 
169 	/* Wakeup anyone watching the list */
170 	wakeup(&intr_config_hook_list);
171 	mtx_unlock(&intr_config_hook_lock);
172 }
173 
174 #ifdef DDB
175 #include <ddb/ddb.h>
176 
177 DB_SHOW_COMMAND(conifhk, db_show_conifhk)
178 {
179 	struct intr_config_hook *hook_entry;
180 	char namebuf[64];
181 	long offset;
182 
183 	TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) {
184 		if (linker_ddb_search_symbol_name(
185 		    (caddr_t)hook_entry->ich_func, namebuf, sizeof(namebuf),
186 		    &offset) == 0) {
187 			db_printf("hook: %p at %s+%#lx arg: %p\n",
188 			    hook_entry->ich_func, namebuf, offset,
189 			    hook_entry->ich_arg);
190 		} else {
191 			db_printf("hook: %p at ??+?? arg %p\n",
192 			    hook_entry->ich_func, hook_entry->ich_arg);
193 		}
194 	}
195 }
196 #endif /* DDB */
197