1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)subr_autoconf.c 8.1 (Berkeley) 6/10/93 36 * 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include "opt_ddb.h" 43 44 #include <sys/param.h> 45 #include <sys/kernel.h> 46 #include <sys/linker.h> 47 #include <sys/lock.h> 48 #include <sys/malloc.h> 49 #include <sys/mutex.h> 50 #include <sys/systm.h> 51 52 /* 53 * Autoconfiguration subroutines. 54 */ 55 56 /* 57 * "Interrupt driven config" functions. 58 */ 59 static STAILQ_HEAD(, intr_config_hook) intr_config_hook_list = 60 STAILQ_HEAD_INITIALIZER(intr_config_hook_list); 61 static struct intr_config_hook *next_to_notify; 62 static struct mtx intr_config_hook_lock; 63 MTX_SYSINIT(intr_config_hook, &intr_config_hook_lock, "intr config", MTX_DEF); 64 65 /* ARGSUSED */ 66 static void run_interrupt_driven_config_hooks(void); 67 68 /* 69 * Private data and a shim function for implementing config_interhook_oneshot(). 70 */ 71 struct oneshot_config_hook { 72 struct intr_config_hook 73 och_hook; /* Must be first */ 74 ich_func_t och_func; 75 void *och_arg; 76 }; 77 78 static void 79 config_intrhook_oneshot_func(void *arg) 80 { 81 struct oneshot_config_hook *ohook; 82 83 ohook = arg; 84 ohook->och_func(ohook->och_arg); 85 config_intrhook_disestablish(&ohook->och_hook); 86 free(ohook, M_DEVBUF); 87 } 88 89 /* 90 * If we wait too long for an interrupt-driven config hook to return, print 91 * a diagnostic. 92 */ 93 #define WARNING_INTERVAL_SECS 60 94 static void 95 run_interrupt_driven_config_hooks_warning(int warned) 96 { 97 struct intr_config_hook *hook_entry; 98 char namebuf[64]; 99 long offset; 100 101 if (warned < 6) { 102 printf("run_interrupt_driven_hooks: still waiting after %d " 103 "seconds for", warned * WARNING_INTERVAL_SECS); 104 STAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) { 105 if (linker_search_symbol_name( 106 (caddr_t)hook_entry->ich_func, namebuf, 107 sizeof(namebuf), &offset) == 0) 108 printf(" %s", namebuf); 109 else 110 printf(" %p", hook_entry->ich_func); 111 } 112 printf("\n"); 113 } 114 KASSERT(warned < 6, 115 ("run_interrupt_driven_config_hooks: waited too long")); 116 } 117 118 static void 119 run_interrupt_driven_config_hooks() 120 { 121 static int running; 122 struct intr_config_hook *hook_entry; 123 124 mtx_lock(&intr_config_hook_lock); 125 126 /* 127 * If hook processing is already active, any newly 128 * registered hooks will eventually be notified. 129 * Let the currently running session issue these 130 * notifications. 131 */ 132 if (running != 0) { 133 mtx_unlock(&intr_config_hook_lock); 134 return; 135 } 136 running = 1; 137 138 while (next_to_notify != NULL) { 139 hook_entry = next_to_notify; 140 next_to_notify = STAILQ_NEXT(hook_entry, ich_links); 141 hook_entry->ich_state = ICHS_RUNNING; 142 mtx_unlock(&intr_config_hook_lock); 143 (*hook_entry->ich_func)(hook_entry->ich_arg); 144 mtx_lock(&intr_config_hook_lock); 145 } 146 147 running = 0; 148 mtx_unlock(&intr_config_hook_lock); 149 } 150 151 static void 152 boot_run_interrupt_driven_config_hooks(void *dummy) 153 { 154 int warned; 155 156 run_interrupt_driven_config_hooks(); 157 158 /* Block boot processing until all hooks are disestablished. */ 159 TSWAIT("config hooks"); 160 mtx_lock(&intr_config_hook_lock); 161 warned = 0; 162 while (!STAILQ_EMPTY(&intr_config_hook_list)) { 163 if (msleep(&intr_config_hook_list, &intr_config_hook_lock, 164 0, "conifhk", WARNING_INTERVAL_SECS * hz) == 165 EWOULDBLOCK) { 166 mtx_unlock(&intr_config_hook_lock); 167 warned++; 168 run_interrupt_driven_config_hooks_warning(warned); 169 mtx_lock(&intr_config_hook_lock); 170 } 171 } 172 mtx_unlock(&intr_config_hook_lock); 173 TSUNWAIT("config hooks"); 174 } 175 176 SYSINIT(intr_config_hooks, SI_SUB_INT_CONFIG_HOOKS, SI_ORDER_FIRST, 177 boot_run_interrupt_driven_config_hooks, NULL); 178 179 /* 180 * Register a hook that will be called after "cold" 181 * autoconfiguration is complete and interrupts can 182 * be used to complete initialization. 183 */ 184 int 185 config_intrhook_establish(struct intr_config_hook *hook) 186 { 187 struct intr_config_hook *hook_entry; 188 189 TSHOLD("config hooks"); 190 mtx_lock(&intr_config_hook_lock); 191 STAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) 192 if (hook_entry == hook) 193 break; 194 if (hook_entry != NULL) { 195 mtx_unlock(&intr_config_hook_lock); 196 printf("config_intrhook_establish: establishing an " 197 "already established hook.\n"); 198 return (1); 199 } 200 STAILQ_INSERT_TAIL(&intr_config_hook_list, hook, ich_links); 201 if (next_to_notify == NULL) 202 next_to_notify = hook; 203 hook->ich_state = ICHS_QUEUED; 204 mtx_unlock(&intr_config_hook_lock); 205 if (cold == 0) 206 /* 207 * XXX Call from a task since not all drivers expect 208 * to be re-entered at the time a hook is established. 209 */ 210 /* XXX Sufficient for modules loaded after initial config??? */ 211 run_interrupt_driven_config_hooks(); 212 return (0); 213 } 214 215 /* 216 * Register a hook function that is automatically unregistered after it runs. 217 */ 218 void 219 config_intrhook_oneshot(ich_func_t func, void *arg) 220 { 221 struct oneshot_config_hook *ohook; 222 223 ohook = malloc(sizeof(*ohook), M_DEVBUF, M_WAITOK); 224 ohook->och_func = func; 225 ohook->och_arg = arg; 226 ohook->och_hook.ich_func = config_intrhook_oneshot_func; 227 ohook->och_hook.ich_arg = ohook; 228 config_intrhook_establish(&ohook->och_hook); 229 } 230 231 static void 232 config_intrhook_disestablish_locked(struct intr_config_hook *hook) 233 { 234 struct intr_config_hook *hook_entry; 235 236 STAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) 237 if (hook_entry == hook) 238 break; 239 if (hook_entry == NULL) 240 panic("config_intrhook_disestablish: disestablishing an " 241 "unestablished hook"); 242 243 if (next_to_notify == hook) 244 next_to_notify = STAILQ_NEXT(hook, ich_links); 245 STAILQ_REMOVE(&intr_config_hook_list, hook, intr_config_hook, ich_links); 246 TSRELEASE("config hooks"); 247 248 /* Wakeup anyone watching the list */ 249 hook->ich_state = ICHS_DONE; 250 wakeup(&intr_config_hook_list); 251 } 252 253 void 254 config_intrhook_disestablish(struct intr_config_hook *hook) 255 { 256 mtx_lock(&intr_config_hook_lock); 257 config_intrhook_disestablish_locked(hook); 258 mtx_unlock(&intr_config_hook_lock); 259 } 260 261 int 262 config_intrhook_drain(struct intr_config_hook *hook) 263 { 264 mtx_lock(&intr_config_hook_lock); 265 266 /* 267 * The config hook has completed, so just return. 268 */ 269 if (hook->ich_state == ICHS_DONE) { 270 mtx_unlock(&intr_config_hook_lock); 271 return (ICHS_DONE); 272 } 273 274 /* 275 * The config hook hasn't started running, just call disestablish. 276 */ 277 if (hook->ich_state == ICHS_QUEUED) { 278 config_intrhook_disestablish_locked(hook); 279 mtx_unlock(&intr_config_hook_lock); 280 return (ICHS_QUEUED); 281 } 282 283 /* 284 * The config hook is running, so wait for it to complete and return. 285 */ 286 while (hook->ich_state != ICHS_DONE) { 287 if (msleep(&intr_config_hook_list, &intr_config_hook_lock, 288 0, "confhd", hz) == EWOULDBLOCK) { 289 // XXX do I whine? 290 } 291 } 292 mtx_unlock(&intr_config_hook_lock); 293 return (ICHS_RUNNING); 294 } 295 296 #ifdef DDB 297 #include <ddb/ddb.h> 298 299 DB_SHOW_COMMAND(conifhk, db_show_conifhk) 300 { 301 struct intr_config_hook *hook_entry; 302 char namebuf[64]; 303 long offset; 304 305 STAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) { 306 if (linker_ddb_search_symbol_name( 307 (caddr_t)hook_entry->ich_func, namebuf, sizeof(namebuf), 308 &offset) == 0) { 309 db_printf("hook: %p at %s+%#lx arg: %p\n", 310 hook_entry->ich_func, namebuf, offset, 311 hook_entry->ich_arg); 312 } else { 313 db_printf("hook: %p at ??+?? arg %p\n", 314 hook_entry->ich_func, hook_entry->ich_arg); 315 } 316 } 317 } 318 #endif /* DDB */ 319