sys/kern/subr_autoconf.c

   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 */