1/*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 1999 Michael Smith <msmith@freebsd.org> 5 * All rights reserved. 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 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29#ifndef _SYS_EVENTHANDLER_H_ 30#define _SYS_EVENTHANDLER_H_ 31 32#include <sys/_eventhandler.h> 33#include <sys/lock.h> 34#include <sys/ktr.h> 35#include <sys/mutex.h> 36#include <sys/queue.h> 37 38#ifdef VIMAGE 39struct eventhandler_entry_vimage { 40 void (* func)(void); /* Original function registered. */ 41 void *ee_arg; /* Original argument registered. */ 42 void *sparep[2]; 43}; 44#endif 45 46struct eventhandler_list { 47 char *el_name; 48 int el_flags; /* Unused. */ 49 u_int el_runcount; 50 struct mtx el_lock; 51 TAILQ_ENTRY(eventhandler_list) el_link; 52 TAILQ_HEAD(,eventhandler_entry) el_entries; 53}; 54 55#define EHL_LOCK(p) mtx_lock(&(p)->el_lock) 56#define EHL_UNLOCK(p) mtx_unlock(&(p)->el_lock) 57#define EHL_LOCK_ASSERT(p, x) mtx_assert(&(p)->el_lock, x) 58 59/* 60 * Macro to invoke the handlers for a given event. 61 */ 62#define _EVENTHANDLER_INVOKE(name, list, ...) do { \ 63 struct eventhandler_entry *_ep; \ 64 struct eventhandler_entry_ ## name *_t; \ 65 \ 66 EHL_LOCK_ASSERT((list), MA_OWNED); \ 67 (list)->el_runcount++; \ 68 KASSERT((list)->el_runcount > 0, \ 69 ("eventhandler_invoke: runcount overflow")); \ 70 CTR0(KTR_EVH, "eventhandler_invoke(\"" __STRING(name) "\")"); \ 71 TAILQ_FOREACH(_ep, &((list)->el_entries), ee_link) { \ 72 if (_ep->ee_priority != EHE_DEAD_PRIORITY) { \ 73 EHL_UNLOCK((list)); \ 74 _t = (struct eventhandler_entry_ ## name *)_ep; \ 75 CTR1(KTR_EVH, "eventhandler_invoke: executing %p", \ 76 (void *)_t->eh_func); \ 77 _t->eh_func(_ep->ee_arg , ## __VA_ARGS__); \ 78 EHL_LOCK((list)); \ 79 } \ 80 } \ 81 KASSERT((list)->el_runcount > 0, \ 82 ("eventhandler_invoke: runcount underflow")); \ 83 (list)->el_runcount--; \ 84 if ((list)->el_runcount == 0) \ 85 eventhandler_prune_list(list); \ 86 EHL_UNLOCK((list)); \ 87} while (0) 88 89/* 90 * You can optionally use the EVENTHANDLER_LIST and EVENTHANDLER_DIRECT macros 91 * to pre-define a symbol for the eventhandler list. This symbol can be used by 92 * EVENTHANDLER_DIRECT_INVOKE, which has the advantage of not needing to do a 93 * locked search of the global list of eventhandler lists. At least 94 * EVENTHANDLER_LIST_DEFINE must be used for EVENTHANDLER_DIRECT_INVOKE to 95 * work. EVENTHANDLER_LIST_DECLARE is only needed if the call to 96 * EVENTHANDLER_DIRECT_INVOKE is in a different compilation unit from 97 * EVENTHANDLER_LIST_DEFINE. If the events are even relatively high frequency 98 * it is suggested that you directly define a list for them. 99 */ 100#define EVENTHANDLER_LIST_DEFINE(name) \ 101struct eventhandler_list *_eventhandler_list_ ## name ; \ 102static void _ehl_init_ ## name (void * ctx __unused) \ 103{ \ 104 _eventhandler_list_ ## name = eventhandler_create_list(#name); \ 105} \ 106SYSINIT(name ## _ehl_init, SI_SUB_EVENTHANDLER, SI_ORDER_ANY, \ 107 _ehl_init_ ## name, NULL); \ 108 struct __hack 109 110#define EVENTHANDLER_DIRECT_INVOKE(name, ...) do { \ 111 struct eventhandler_list *_el; \ 112 \ 113 _el = _eventhandler_list_ ## name ; \ 114 if (!TAILQ_EMPTY(&_el->el_entries)) { \ 115 EHL_LOCK(_el); \ 116 _EVENTHANDLER_INVOKE(name, _el , ## __VA_ARGS__); \ 117 } \ 118} while (0) 119 120#define EVENTHANDLER_DEFINE(name, func, arg, priority) \ 121 static eventhandler_tag name ## _tag; \ 122 static void name ## _evh_init(void *ctx) \ 123 { \ 124 name ## _tag = EVENTHANDLER_REGISTER(name, func, ctx, \ 125 priority); \ 126 } \ 127 SYSINIT(name ## _evh_init, SI_SUB_CONFIGURE, SI_ORDER_ANY, \ 128 name ## _evh_init, arg); \ 129 struct __hack 130 131#define EVENTHANDLER_INVOKE(name, ...) \ 132do { \ 133 struct eventhandler_list *_el; \ 134 \ 135 if ((_el = eventhandler_find_list(#name)) != NULL) \ 136 _EVENTHANDLER_INVOKE(name, _el , ## __VA_ARGS__); \ 137} while (0) 138 139#define EVENTHANDLER_REGISTER(name, func, arg, priority) \ 140 eventhandler_register(NULL, #name, func, arg, priority) 141 142#define EVENTHANDLER_DEREGISTER(name, tag) \ 143do { \ 144 struct eventhandler_list *_el; \ 145 \ 146 if ((_el = eventhandler_find_list(#name)) != NULL) \ 147 eventhandler_deregister(_el, tag); \ 148} while (0) 149 150#define EVENTHANDLER_DEREGISTER_NOWAIT(name, tag) \ 151do { \ 152 struct eventhandler_list *_el; \ 153 \ 154 if ((_el = eventhandler_find_list(#name)) != NULL) \ 155 eventhandler_deregister_nowait(_el, tag); \ 156} while (0) 157 158eventhandler_tag eventhandler_register(struct eventhandler_list *list, 159 const char *name, void *func, void *arg, int priority); 160void eventhandler_deregister(struct eventhandler_list *list, 161 eventhandler_tag tag); 162void eventhandler_deregister_nowait(struct eventhandler_list *list, 163 eventhandler_tag tag); 164struct eventhandler_list *eventhandler_find_list(const char *name); 165void eventhandler_prune_list(struct eventhandler_list *list); 166struct eventhandler_list *eventhandler_create_list(const char *name); 167 168#ifdef VIMAGE 169typedef void (*vimage_iterator_func_t)(void *, ...); 170 171eventhandler_tag vimage_eventhandler_register(struct eventhandler_list *list, 172 const char *name, void *func, void *arg, int priority, 173 vimage_iterator_func_t); 174#endif 175 176/* 177 * Standard system event queues. 178 */ 179 180/* Generic priority levels */ 181#define EVENTHANDLER_PRI_FIRST 0 182#define EVENTHANDLER_PRI_ANY 10000 183#define EVENTHANDLER_PRI_LAST 20000 184 185/* 186 * Successive shutdown events invoked by kern_reboot(9). 187 * 188 * Handlers will receive the 'howto' value as their second argument. 189 * 190 * All handlers must be prepared to be executed from a panic/debugger context; 191 * see the man page for details. 192 */ 193typedef void (*shutdown_fn)(void *, int); 194 195#define SHUTDOWN_PRI_FIRST EVENTHANDLER_PRI_FIRST 196#define SHUTDOWN_PRI_DEFAULT EVENTHANDLER_PRI_ANY 197#define SHUTDOWN_PRI_LAST EVENTHANDLER_PRI_LAST 198 199EVENTHANDLER_DECLARE(shutdown_pre_sync, shutdown_fn); /* before fs sync */ 200EVENTHANDLER_DECLARE(shutdown_post_sync, shutdown_fn); /* after fs sync */ 201EVENTHANDLER_DECLARE(shutdown_final, shutdown_fn); 202 203/* Power state change events */ 204typedef void (*power_change_fn)(void *); 205EVENTHANDLER_DECLARE(power_resume, power_change_fn); 206EVENTHANDLER_DECLARE(power_suspend, power_change_fn); 207EVENTHANDLER_DECLARE(power_suspend_early, power_change_fn); 208 209/* Low memory event */ 210typedef void (*vm_lowmem_handler_t)(void *, int); 211#define LOWMEM_PRI_DEFAULT EVENTHANDLER_PRI_FIRST 212EVENTHANDLER_DECLARE(vm_lowmem, vm_lowmem_handler_t); 213/* Some of mbuf(9) zones reached maximum */ 214EVENTHANDLER_DECLARE(mbuf_lowmem, vm_lowmem_handler_t); 215 216/* Root mounted event */ 217typedef void (*mountroot_handler_t)(void *); 218EVENTHANDLER_DECLARE(mountroot, mountroot_handler_t); 219 220/* File system mount events */ 221struct mount; 222struct vnode; 223struct thread; 224typedef void (*vfs_mounted_notify_fn)(void *, struct mount *, struct vnode *, 225 struct thread *); 226typedef void (*vfs_unmounted_notify_fn)(void *, struct mount *, 227 struct thread *); 228EVENTHANDLER_DECLARE(vfs_mounted, vfs_mounted_notify_fn); 229EVENTHANDLER_DECLARE(vfs_unmounted, vfs_unmounted_notify_fn); 230 231/* 232 * Process events 233 * process_fork and exit handlers are called without Giant. 234 * exec handlers are called with Giant, but that is by accident. 235 */ 236struct proc; 237struct image_params; 238 239typedef void (*exitlist_fn)(void *, struct proc *); 240typedef void (*forklist_fn)(void *, struct proc *, struct proc *, int); 241typedef void (*execlist_fn)(void *, struct proc *, struct image_params *); 242typedef void (*proc_ctor_fn)(void *, struct proc *); 243typedef void (*proc_dtor_fn)(void *, struct proc *); 244typedef void (*proc_init_fn)(void *, struct proc *); 245typedef void (*proc_fini_fn)(void *, struct proc *); 246EVENTHANDLER_DECLARE(process_ctor, proc_ctor_fn); 247EVENTHANDLER_DECLARE(process_dtor, proc_dtor_fn); 248EVENTHANDLER_DECLARE(process_init, proc_init_fn); 249EVENTHANDLER_DECLARE(process_fini, proc_fini_fn); 250EVENTHANDLER_DECLARE(process_exit, exitlist_fn); 251EVENTHANDLER_DECLARE(process_fork, forklist_fn); 252EVENTHANDLER_DECLARE(process_exec, execlist_fn); 253 254/* 255 * application dump event 256 */ 257typedef void (*app_coredump_start_fn)(void *, struct thread *, char *name); 258typedef void (*app_coredump_progress_fn)(void *, struct thread *td, int byte_count); 259typedef void (*app_coredump_finish_fn)(void *, struct thread *td); 260typedef void (*app_coredump_error_fn)(void *, struct thread *td, char *msg, ...); 261 262EVENTHANDLER_DECLARE(app_coredump_start, app_coredump_start_fn); 263EVENTHANDLER_DECLARE(app_coredump_progress, app_coredump_progress_fn); 264EVENTHANDLER_DECLARE(app_coredump_finish, app_coredump_finish_fn); 265EVENTHANDLER_DECLARE(app_coredump_error, app_coredump_error_fn); 266 267typedef void (*thread_ctor_fn)(void *, struct thread *); 268typedef void (*thread_dtor_fn)(void *, struct thread *); 269typedef void (*thread_fini_fn)(void *, struct thread *); 270typedef void (*thread_init_fn)(void *, struct thread *); 271EVENTHANDLER_DECLARE(thread_ctor, thread_ctor_fn); 272EVENTHANDLER_DECLARE(thread_dtor, thread_dtor_fn); 273EVENTHANDLER_DECLARE(thread_init, thread_init_fn); 274EVENTHANDLER_DECLARE(thread_fini, thread_fini_fn); 275 276typedef void (*uma_zone_chfn)(void *); 277EVENTHANDLER_DECLARE(nmbclusters_change, uma_zone_chfn); 278EVENTHANDLER_DECLARE(nmbufs_change, uma_zone_chfn); 279EVENTHANDLER_DECLARE(maxsockets_change, uma_zone_chfn); 280 281/* Kernel linker file load and unload events */ 282struct linker_file; 283typedef void (*kld_load_fn)(void *, struct linker_file *); 284typedef void (*kld_unload_fn)(void *, const char *, caddr_t, size_t); 285typedef void (*kld_unload_try_fn)(void *, struct linker_file *, int *); 286EVENTHANDLER_DECLARE(kld_load, kld_load_fn); 287EVENTHANDLER_DECLARE(kld_unload, kld_unload_fn); 288EVENTHANDLER_DECLARE(kld_unload_try, kld_unload_try_fn); 289 290/* Generic graphics framebuffer interface */ 291struct fb_info; 292typedef void (*register_framebuffer_fn)(void *, struct fb_info *); 293typedef void (*unregister_framebuffer_fn)(void *, struct fb_info *); 294EVENTHANDLER_DECLARE(register_framebuffer, register_framebuffer_fn); 295EVENTHANDLER_DECLARE(unregister_framebuffer, unregister_framebuffer_fn); 296 297/* Veto ada attachment */ 298struct cam_path; 299struct ata_params; 300typedef void (*ada_probe_veto_fn)(void *, struct cam_path *, 301 struct ata_params *, int *); 302EVENTHANDLER_DECLARE(ada_probe_veto, ada_probe_veto_fn); 303 304/* Swap device events */ 305struct swdevt; 306typedef void (*swapon_fn)(void *, struct swdevt *); 307typedef void (*swapoff_fn)(void *, struct swdevt *); 308EVENTHANDLER_DECLARE(swapon, swapon_fn); 309EVENTHANDLER_DECLARE(swapoff, swapoff_fn); 310 311/* newbus device events */ 312enum evhdev_detach { 313 EVHDEV_DETACH_BEGIN, /* Before detach() is called */ 314 EVHDEV_DETACH_COMPLETE, /* After detach() returns 0 */ 315 EVHDEV_DETACH_FAILED /* After detach() returns err */ 316}; 317typedef void (*device_attach_fn)(void *, device_t); 318typedef void (*device_detach_fn)(void *, device_t, enum evhdev_detach); 319typedef void (*device_nomatch_fn)(void *, device_t); 320EVENTHANDLER_DECLARE(device_attach, device_attach_fn); 321EVENTHANDLER_DECLARE(device_detach, device_detach_fn); 322EVENTHANDLER_DECLARE(device_nomatch, device_nomatch_fn); 323 324/* Interface address addition and removal event */ 325struct ifaddr; 326typedef void (*rt_addrmsg_fn)(void *, struct ifaddr *, int); 327EVENTHANDLER_DECLARE(rt_addrmsg, rt_addrmsg_fn); 328 329/* Kernel environment variable change event */ 330typedef void (*env_change_fn)(void *, const char *); 331EVENTHANDLER_DECLARE(setenv, env_change_fn); 332EVENTHANDLER_DECLARE(unsetenv, env_change_fn); 333 334#endif /* _SYS_EVENTHANDLER_H_ */ 335