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 39 struct 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 46 struct 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) \ 101 struct eventhandler_list *_eventhandler_list_ ## name ; \ 102 static void _ehl_init_ ## name (void * ctx __unused) \ 103 { \ 104 _eventhandler_list_ ## name = eventhandler_create_list(#name); \ 105 } \ 106 SYSINIT(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, ...) \ 132 do { \ 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) \ 143 do { \ 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) \ 151 do { \ 152 struct eventhandler_list *_el; \ 153 \ 154 if ((_el = eventhandler_find_list(#name)) != NULL) \ 155 eventhandler_deregister_nowait(_el, tag); \ 156 } while (0) 157 158 eventhandler_tag eventhandler_register(struct eventhandler_list *list, 159 const char *name, void *func, void *arg, int priority); 160 void eventhandler_deregister(struct eventhandler_list *list, 161 eventhandler_tag tag); 162 void eventhandler_deregister_nowait(struct eventhandler_list *list, 163 eventhandler_tag tag); 164 struct eventhandler_list *eventhandler_find_list(const char *name); 165 void eventhandler_prune_list(struct eventhandler_list *list); 166 struct eventhandler_list *eventhandler_create_list(const char *name); 167 168 #ifdef VIMAGE 169 typedef void (*vimage_iterator_func_t)(void *, ...); 170 171 eventhandler_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 */ 193 typedef 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 198 199 EVENTHANDLER_DECLARE(shutdown_pre_sync, shutdown_fn); /* before fs sync */ 200 EVENTHANDLER_DECLARE(shutdown_post_sync, shutdown_fn); /* after fs sync */ 201 EVENTHANDLER_DECLARE(shutdown_final, shutdown_fn); 202 203 /* Power state change events */ 204 typedef void (*power_change_fn)(void *); 205 EVENTHANDLER_DECLARE(power_resume, power_change_fn); 206 EVENTHANDLER_DECLARE(power_suspend, power_change_fn); 207 EVENTHANDLER_DECLARE(power_suspend_early, power_change_fn); 208 209 /* Low memory event */ 210 typedef void (*vm_lowmem_handler_t)(void *, int); 211 #define LOWMEM_PRI_DEFAULT EVENTHANDLER_PRI_FIRST 212 EVENTHANDLER_DECLARE(vm_lowmem, vm_lowmem_handler_t); 213 /* Some of mbuf(9) zones reached maximum */ 214 EVENTHANDLER_DECLARE(mbuf_lowmem, vm_lowmem_handler_t); 215 216 /* Root mounted event */ 217 typedef void (*mountroot_handler_t)(void *); 218 EVENTHANDLER_DECLARE(mountroot, mountroot_handler_t); 219 220 /* File system mount events */ 221 struct mount; 222 struct vnode; 223 struct thread; 224 typedef void (*vfs_mounted_notify_fn)(void *, struct mount *, struct vnode *, 225 struct thread *); 226 typedef void (*vfs_unmounted_notify_fn)(void *, struct mount *, 227 struct thread *); 228 EVENTHANDLER_DECLARE(vfs_mounted, vfs_mounted_notify_fn); 229 EVENTHANDLER_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 */ 236 struct proc; 237 struct image_params; 238 239 typedef void (*exitlist_fn)(void *, struct proc *); 240 typedef void (*forklist_fn)(void *, struct proc *, struct proc *, int); 241 typedef void (*execlist_fn)(void *, struct proc *, struct image_params *); 242 typedef void (*proc_ctor_fn)(void *, struct proc *); 243 typedef void (*proc_dtor_fn)(void *, struct proc *); 244 typedef void (*proc_init_fn)(void *, struct proc *); 245 typedef void (*proc_fini_fn)(void *, struct proc *); 246 EVENTHANDLER_DECLARE(process_ctor, proc_ctor_fn); 247 EVENTHANDLER_DECLARE(process_dtor, proc_dtor_fn); 248 EVENTHANDLER_DECLARE(process_init, proc_init_fn); 249 EVENTHANDLER_DECLARE(process_fini, proc_fini_fn); 250 EVENTHANDLER_DECLARE(process_exit, exitlist_fn); 251 EVENTHANDLER_DECLARE(process_fork, forklist_fn); 252 EVENTHANDLER_DECLARE(process_exec, execlist_fn); 253 254 /* 255 * application dump event 256 */ 257 typedef void (*app_coredump_start_fn)(void *, struct thread *, char *name); 258 typedef void (*app_coredump_progress_fn)(void *, struct thread *td, int byte_count); 259 typedef void (*app_coredump_finish_fn)(void *, struct thread *td); 260 typedef void (*app_coredump_error_fn)(void *, struct thread *td, char *msg, ...); 261 262 EVENTHANDLER_DECLARE(app_coredump_start, app_coredump_start_fn); 263 EVENTHANDLER_DECLARE(app_coredump_progress, app_coredump_progress_fn); 264 EVENTHANDLER_DECLARE(app_coredump_finish, app_coredump_finish_fn); 265 EVENTHANDLER_DECLARE(app_coredump_error, app_coredump_error_fn); 266 267 typedef void (*thread_ctor_fn)(void *, struct thread *); 268 typedef void (*thread_dtor_fn)(void *, struct thread *); 269 typedef void (*thread_fini_fn)(void *, struct thread *); 270 typedef void (*thread_init_fn)(void *, struct thread *); 271 EVENTHANDLER_DECLARE(thread_ctor, thread_ctor_fn); 272 EVENTHANDLER_DECLARE(thread_dtor, thread_dtor_fn); 273 EVENTHANDLER_DECLARE(thread_init, thread_init_fn); 274 EVENTHANDLER_DECLARE(thread_fini, thread_fini_fn); 275 276 typedef void (*uma_zone_chfn)(void *); 277 EVENTHANDLER_DECLARE(nmbclusters_change, uma_zone_chfn); 278 EVENTHANDLER_DECLARE(nmbufs_change, uma_zone_chfn); 279 EVENTHANDLER_DECLARE(maxsockets_change, uma_zone_chfn); 280 281 /* Kernel linker file load and unload events */ 282 struct linker_file; 283 typedef void (*kld_load_fn)(void *, struct linker_file *); 284 typedef void (*kld_unload_fn)(void *, const char *, caddr_t, size_t); 285 typedef void (*kld_unload_try_fn)(void *, struct linker_file *, int *); 286 EVENTHANDLER_DECLARE(kld_load, kld_load_fn); 287 EVENTHANDLER_DECLARE(kld_unload, kld_unload_fn); 288 EVENTHANDLER_DECLARE(kld_unload_try, kld_unload_try_fn); 289 290 /* Generic graphics framebuffer interface */ 291 struct fb_info; 292 typedef void (*register_framebuffer_fn)(void *, struct fb_info *); 293 typedef void (*unregister_framebuffer_fn)(void *, struct fb_info *); 294 EVENTHANDLER_DECLARE(register_framebuffer, register_framebuffer_fn); 295 EVENTHANDLER_DECLARE(unregister_framebuffer, unregister_framebuffer_fn); 296 297 /* Veto ada attachment */ 298 struct cam_path; 299 struct ata_params; 300 typedef void (*ada_probe_veto_fn)(void *, struct cam_path *, 301 struct ata_params *, int *); 302 EVENTHANDLER_DECLARE(ada_probe_veto, ada_probe_veto_fn); 303 304 /* Swap device events */ 305 struct swdevt; 306 typedef void (*swapon_fn)(void *, struct swdevt *); 307 typedef void (*swapoff_fn)(void *, struct swdevt *); 308 EVENTHANDLER_DECLARE(swapon, swapon_fn); 309 EVENTHANDLER_DECLARE(swapoff, swapoff_fn); 310 311 /* newbus device events */ 312 enum 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 }; 317 typedef void (*device_attach_fn)(void *, device_t); 318 typedef void (*device_detach_fn)(void *, device_t, enum evhdev_detach); 319 typedef void (*device_nomatch_fn)(void *, device_t); 320 EVENTHANDLER_DECLARE(device_attach, device_attach_fn); 321 EVENTHANDLER_DECLARE(device_detach, device_detach_fn); 322 EVENTHANDLER_DECLARE(device_nomatch, device_nomatch_fn); 323 324 /* Interface address addition and removal event */ 325 struct ifaddr; 326 typedef void (*rt_addrmsg_fn)(void *, struct ifaddr *, int); 327 EVENTHANDLER_DECLARE(rt_addrmsg, rt_addrmsg_fn); 328 329 /* Kernel environment variable change event */ 330 typedef void (*env_change_fn)(void *, const char *); 331 EVENTHANDLER_DECLARE(setenv, env_change_fn); 332 EVENTHANDLER_DECLARE(unsetenv, env_change_fn); 333 334 #endif /* _SYS_EVENTHANDLER_H_ */ 335