2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 1999 Michael Smith <msmith@freebsd.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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
31 #ifndef _SYS_EVENTHANDLER_H_
32 #define _SYS_EVENTHANDLER_H_
36 #include <sys/mutex.h>
37 #include <sys/queue.h>
39 struct eventhandler_entry {
40 TAILQ_ENTRY(eventhandler_entry) ee_link;
42 #define EHE_DEAD_PRIORITY (-1)
47 struct eventhandler_entry_vimage {
48 void (* func)(void); /* Original function registered. */
49 void *ee_arg; /* Original argument registered. */
54 struct eventhandler_list {
56 int el_flags; /* Unused. */
59 TAILQ_ENTRY(eventhandler_list) el_link;
60 TAILQ_HEAD(,eventhandler_entry) el_entries;
63 typedef struct eventhandler_entry *eventhandler_tag;
65 #define EHL_LOCK(p) mtx_lock(&(p)->el_lock)
66 #define EHL_UNLOCK(p) mtx_unlock(&(p)->el_lock)
67 #define EHL_LOCK_ASSERT(p, x) mtx_assert(&(p)->el_lock, x)
70 * Macro to invoke the handlers for a given event.
72 #define _EVENTHANDLER_INVOKE(name, list, ...) do { \
73 struct eventhandler_entry *_ep; \
74 struct eventhandler_entry_ ## name *_t; \
76 EHL_LOCK_ASSERT((list), MA_OWNED); \
77 (list)->el_runcount++; \
78 KASSERT((list)->el_runcount > 0, \
79 ("eventhandler_invoke: runcount overflow")); \
80 CTR0(KTR_EVH, "eventhandler_invoke(\"" __STRING(name) "\")"); \
81 TAILQ_FOREACH(_ep, &((list)->el_entries), ee_link) { \
82 if (_ep->ee_priority != EHE_DEAD_PRIORITY) { \
84 _t = (struct eventhandler_entry_ ## name *)_ep; \
85 CTR1(KTR_EVH, "eventhandler_invoke: executing %p", \
86 (void *)_t->eh_func); \
87 _t->eh_func(_ep->ee_arg , ## __VA_ARGS__); \
91 KASSERT((list)->el_runcount > 0, \
92 ("eventhandler_invoke: runcount underflow")); \
93 (list)->el_runcount--; \
94 if ((list)->el_runcount == 0) \
95 eventhandler_prune_list(list); \
100 * You can optionally use the EVENTHANDLER_LIST and EVENTHANDLER_DIRECT macros
101 * to pre-define a symbol for the eventhandler list. This symbol can be used by
102 * EVENTHANDLER_DIRECT_INVOKE, which has the advantage of not needing to do a
103 * locked search of the global list of eventhandler lists. At least
104 * EVENTHANDLER_LIST_DEFINE must be be used for EVENTHANDLER_DIRECT_INVOKE to
105 * work. EVENTHANDLER_LIST_DECLARE is only needed if the call to
106 * EVENTHANDLER_DIRECT_INVOKE is in a different compilation unit from
107 * EVENTHANDLER_LIST_DEFINE. If the events are even relatively high frequency
108 * it is suggested that you directly define a list for them.
110 #define EVENTHANDLER_LIST_DECLARE(name) \
111 extern struct eventhandler_list *_eventhandler_list_ ## name \
113 #define EVENTHANDLER_LIST_DEFINE(name) \
114 struct eventhandler_list *_eventhandler_list_ ## name ; \
115 static void _ehl_init_ ## name (void * ctx __unused) \
117 _eventhandler_list_ ## name = eventhandler_create_list(#name); \
119 SYSINIT(name ## _ehl_init, SI_SUB_EVENTHANDLER, SI_ORDER_ANY, \
120 _ehl_init_ ## name, NULL); \
123 #define EVENTHANDLER_DIRECT_INVOKE(name, ...) do { \
124 struct eventhandler_list *_el; \
126 _el = _eventhandler_list_ ## name ; \
127 if (!TAILQ_EMPTY(&_el->el_entries)) { \
129 _EVENTHANDLER_INVOKE(name, _el , ## __VA_ARGS__); \
134 * Event handlers need to be declared, but do not need to be defined. The
135 * declaration must be in scope wherever the handler is to be invoked.
137 #define EVENTHANDLER_DECLARE(name, type) \
138 struct eventhandler_entry_ ## name \
140 struct eventhandler_entry ee; \
145 #define EVENTHANDLER_DEFINE(name, func, arg, priority) \
146 static eventhandler_tag name ## _tag; \
147 static void name ## _evh_init(void *ctx) \
149 name ## _tag = EVENTHANDLER_REGISTER(name, func, ctx, \
152 SYSINIT(name ## _evh_init, SI_SUB_CONFIGURE, SI_ORDER_ANY, \
153 name ## _evh_init, arg); \
156 #define EVENTHANDLER_INVOKE(name, ...) \
158 struct eventhandler_list *_el; \
160 if ((_el = eventhandler_find_list(#name)) != NULL) \
161 _EVENTHANDLER_INVOKE(name, _el , ## __VA_ARGS__); \
164 #define EVENTHANDLER_REGISTER(name, func, arg, priority) \
165 eventhandler_register(NULL, #name, func, arg, priority)
167 #define EVENTHANDLER_DEREGISTER(name, tag) \
169 struct eventhandler_list *_el; \
171 if ((_el = eventhandler_find_list(#name)) != NULL) \
172 eventhandler_deregister(_el, tag); \
175 #define EVENTHANDLER_DEREGISTER_NOWAIT(name, tag) \
177 struct eventhandler_list *_el; \
179 if ((_el = eventhandler_find_list(#name)) != NULL) \
180 eventhandler_deregister_nowait(_el, tag); \
183 eventhandler_tag eventhandler_register(struct eventhandler_list *list,
184 const char *name, void *func, void *arg, int priority);
185 void eventhandler_deregister(struct eventhandler_list *list,
186 eventhandler_tag tag);
187 void eventhandler_deregister_nowait(struct eventhandler_list *list,
188 eventhandler_tag tag);
189 struct eventhandler_list *eventhandler_find_list(const char *name);
190 void eventhandler_prune_list(struct eventhandler_list *list);
191 struct eventhandler_list *eventhandler_create_list(const char *name);
194 typedef void (*vimage_iterator_func_t)(void *, ...);
196 eventhandler_tag vimage_eventhandler_register(struct eventhandler_list *list,
197 const char *name, void *func, void *arg, int priority,
198 vimage_iterator_func_t);
202 * Standard system event queues.
205 /* Generic priority levels */
206 #define EVENTHANDLER_PRI_FIRST 0
207 #define EVENTHANDLER_PRI_ANY 10000
208 #define EVENTHANDLER_PRI_LAST 20000
210 /* Shutdown events */
211 typedef void (*shutdown_fn)(void *, int);
213 #define SHUTDOWN_PRI_FIRST EVENTHANDLER_PRI_FIRST
214 #define SHUTDOWN_PRI_DEFAULT EVENTHANDLER_PRI_ANY
215 #define SHUTDOWN_PRI_LAST EVENTHANDLER_PRI_LAST
217 EVENTHANDLER_DECLARE(shutdown_pre_sync, shutdown_fn); /* before fs sync */
218 EVENTHANDLER_DECLARE(shutdown_post_sync, shutdown_fn); /* after fs sync */
219 EVENTHANDLER_DECLARE(shutdown_final, shutdown_fn);
221 /* Power state change events */
222 typedef void (*power_change_fn)(void *);
223 EVENTHANDLER_DECLARE(power_resume, power_change_fn);
224 EVENTHANDLER_DECLARE(power_suspend, power_change_fn);
225 EVENTHANDLER_DECLARE(power_suspend_early, power_change_fn);
227 /* Low memory event */
228 typedef void (*vm_lowmem_handler_t)(void *, int);
229 #define LOWMEM_PRI_DEFAULT EVENTHANDLER_PRI_FIRST
230 EVENTHANDLER_DECLARE(vm_lowmem, vm_lowmem_handler_t);
232 /* Root mounted event */
233 typedef void (*mountroot_handler_t)(void *);
234 EVENTHANDLER_DECLARE(mountroot, mountroot_handler_t);
236 /* File system mount events */
240 typedef void (*vfs_mounted_notify_fn)(void *, struct mount *, struct vnode *,
242 typedef void (*vfs_unmounted_notify_fn)(void *, struct mount *,
244 EVENTHANDLER_DECLARE(vfs_mounted, vfs_mounted_notify_fn);
245 EVENTHANDLER_DECLARE(vfs_unmounted, vfs_unmounted_notify_fn);
249 * process_fork and exit handlers are called without Giant.
250 * exec handlers are called with Giant, but that is by accident.
255 typedef void (*exitlist_fn)(void *, struct proc *);
256 typedef void (*forklist_fn)(void *, struct proc *, struct proc *, int);
257 typedef void (*execlist_fn)(void *, struct proc *, struct image_params *);
258 typedef void (*proc_ctor_fn)(void *, struct proc *);
259 typedef void (*proc_dtor_fn)(void *, struct proc *);
260 typedef void (*proc_init_fn)(void *, struct proc *);
261 typedef void (*proc_fini_fn)(void *, struct proc *);
262 EVENTHANDLER_DECLARE(process_ctor, proc_ctor_fn);
263 EVENTHANDLER_DECLARE(process_dtor, proc_dtor_fn);
264 EVENTHANDLER_DECLARE(process_init, proc_init_fn);
265 EVENTHANDLER_DECLARE(process_fini, proc_fini_fn);
266 EVENTHANDLER_DECLARE(process_exit, exitlist_fn);
267 EVENTHANDLER_DECLARE(process_fork, forklist_fn);
268 EVENTHANDLER_DECLARE(process_exec, execlist_fn);
271 * application dump event
273 typedef void (*app_coredump_start_fn)(void *, struct thread *, char *name);
274 typedef void (*app_coredump_progress_fn)(void *, struct thread *td, int byte_count);
275 typedef void (*app_coredump_finish_fn)(void *, struct thread *td);
276 typedef void (*app_coredump_error_fn)(void *, struct thread *td, char *msg, ...);
278 EVENTHANDLER_DECLARE(app_coredump_start, app_coredump_start_fn);
279 EVENTHANDLER_DECLARE(app_coredump_progress, app_coredump_progress_fn);
280 EVENTHANDLER_DECLARE(app_coredump_finish, app_coredump_finish_fn);
281 EVENTHANDLER_DECLARE(app_coredump_error, app_coredump_error_fn);
283 typedef void (*thread_ctor_fn)(void *, struct thread *);
284 typedef void (*thread_dtor_fn)(void *, struct thread *);
285 typedef void (*thread_fini_fn)(void *, struct thread *);
286 typedef void (*thread_init_fn)(void *, struct thread *);
287 EVENTHANDLER_DECLARE(thread_ctor, thread_ctor_fn);
288 EVENTHANDLER_DECLARE(thread_dtor, thread_dtor_fn);
289 EVENTHANDLER_DECLARE(thread_init, thread_init_fn);
290 EVENTHANDLER_DECLARE(thread_fini, thread_fini_fn);
292 typedef void (*uma_zone_chfn)(void *);
293 EVENTHANDLER_DECLARE(nmbclusters_change, uma_zone_chfn);
294 EVENTHANDLER_DECLARE(nmbufs_change, uma_zone_chfn);
295 EVENTHANDLER_DECLARE(maxsockets_change, uma_zone_chfn);
297 /* Kernel linker file load and unload events */
299 typedef void (*kld_load_fn)(void *, struct linker_file *);
300 typedef void (*kld_unload_fn)(void *, const char *, caddr_t, size_t);
301 typedef void (*kld_unload_try_fn)(void *, struct linker_file *, int *);
302 EVENTHANDLER_DECLARE(kld_load, kld_load_fn);
303 EVENTHANDLER_DECLARE(kld_unload, kld_unload_fn);
304 EVENTHANDLER_DECLARE(kld_unload_try, kld_unload_try_fn);
306 /* Generic graphics framebuffer interface */
308 typedef void (*register_framebuffer_fn)(void *, struct fb_info *);
309 typedef void (*unregister_framebuffer_fn)(void *, struct fb_info *);
310 EVENTHANDLER_DECLARE(register_framebuffer, register_framebuffer_fn);
311 EVENTHANDLER_DECLARE(unregister_framebuffer, unregister_framebuffer_fn);
313 /* Veto ada attachment */
316 typedef void (*ada_probe_veto_fn)(void *, struct cam_path *,
317 struct ata_params *, int *);
318 EVENTHANDLER_DECLARE(ada_probe_veto, ada_probe_veto_fn);
320 /* Swap device events */
322 typedef void (*swapon_fn)(void *, struct swdevt *);
323 typedef void (*swapoff_fn)(void *, struct swdevt *);
324 EVENTHANDLER_DECLARE(swapon, swapon_fn);
325 EVENTHANDLER_DECLARE(swapoff, swapoff_fn);
327 /* newbus device events */
329 EVHDEV_DETACH_BEGIN, /* Before detach() is called */
330 EVHDEV_DETACH_COMPLETE, /* After detach() returns 0 */
331 EVHDEV_DETACH_FAILED /* After detach() returns err */
333 typedef void (*device_attach_fn)(void *, device_t);
334 typedef void (*device_detach_fn)(void *, device_t, enum evhdev_detach);
335 EVENTHANDLER_DECLARE(device_attach, device_attach_fn);
336 EVENTHANDLER_DECLARE(device_detach, device_detach_fn);
338 #endif /* _SYS_EVENTHANDLER_H_ */