2 * SPDX-License-Identifier: BSD-2-Clause
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
29 #ifndef _SYS_EVENTHANDLER_H_
30 #define _SYS_EVENTHANDLER_H_
32 #include <sys/_eventhandler.h>
35 #include <sys/mutex.h>
36 #include <sys/queue.h>
39 struct eventhandler_entry_vimage {
40 void (* func)(void); /* Original function registered. */
41 void *ee_arg; /* Original argument registered. */
46 struct eventhandler_list {
48 int el_flags; /* Unused. */
51 TAILQ_ENTRY(eventhandler_list) el_link;
52 TAILQ_HEAD(,eventhandler_entry) el_entries;
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)
60 * Macro to invoke the handlers for a given event.
62 #define _EVENTHANDLER_INVOKE(name, list, ...) do { \
63 struct eventhandler_entry *_ep; \
64 struct eventhandler_entry_ ## name *_t; \
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) { \
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__); \
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); \
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.
100 #define EVENTHANDLER_LIST_DEFINE(name) \
101 struct eventhandler_list *_eventhandler_list_ ## name ; \
102 static void _ehl_init_ ## name (void * ctx __unused) \
104 _eventhandler_list_ ## name = eventhandler_create_list(#name); \
106 SYSINIT(name ## _ehl_init, SI_SUB_EVENTHANDLER, SI_ORDER_ANY, \
107 _ehl_init_ ## name, NULL); \
110 #define EVENTHANDLER_DIRECT_INVOKE(name, ...) do { \
111 struct eventhandler_list *_el; \
113 _el = _eventhandler_list_ ## name ; \
114 if (!TAILQ_EMPTY(&_el->el_entries)) { \
116 _EVENTHANDLER_INVOKE(name, _el , ## __VA_ARGS__); \
120 #define EVENTHANDLER_DEFINE(name, func, arg, priority) \
121 static eventhandler_tag name ## _tag; \
122 static void name ## _evh_init(void *ctx) \
124 name ## _tag = EVENTHANDLER_REGISTER(name, func, ctx, \
127 SYSINIT(name ## _evh_init, SI_SUB_CONFIGURE, SI_ORDER_ANY, \
128 name ## _evh_init, arg); \
131 #define EVENTHANDLER_INVOKE(name, ...) \
133 struct eventhandler_list *_el; \
135 if ((_el = eventhandler_find_list(#name)) != NULL) \
136 _EVENTHANDLER_INVOKE(name, _el , ## __VA_ARGS__); \
139 #define EVENTHANDLER_REGISTER(name, func, arg, priority) \
140 eventhandler_register(NULL, #name, func, arg, priority)
142 #define EVENTHANDLER_DEREGISTER(name, tag) \
144 struct eventhandler_list *_el; \
146 if ((_el = eventhandler_find_list(#name)) != NULL) \
147 eventhandler_deregister(_el, tag); \
150 #define EVENTHANDLER_DEREGISTER_NOWAIT(name, tag) \
152 struct eventhandler_list *_el; \
154 if ((_el = eventhandler_find_list(#name)) != NULL) \
155 eventhandler_deregister_nowait(_el, tag); \
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);
169 typedef void (*vimage_iterator_func_t)(void *, ...);
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);
177 * Standard system event queues.
180 /* Generic priority levels */
181 #define EVENTHANDLER_PRI_FIRST 0
182 #define EVENTHANDLER_PRI_ANY 10000
183 #define EVENTHANDLER_PRI_LAST 20000
186 * Successive shutdown events invoked by kern_reboot(9).
188 * Handlers will receive the 'howto' value as their second argument.
190 * All handlers must be prepared to be executed from a panic/debugger context;
191 * see the man page for details.
193 typedef void (*shutdown_fn)(void *, int);
195 #define SHUTDOWN_PRI_FIRST EVENTHANDLER_PRI_FIRST
196 #define SHUTDOWN_PRI_DEFAULT EVENTHANDLER_PRI_ANY
197 #define SHUTDOWN_PRI_LAST EVENTHANDLER_PRI_LAST
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);
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);
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);
216 /* Root mounted event */
217 typedef void (*mountroot_handler_t)(void *);
218 EVENTHANDLER_DECLARE(mountroot, mountroot_handler_t);
220 /* File system mount events */
224 typedef void (*vfs_mounted_notify_fn)(void *, struct mount *, struct vnode *,
226 typedef void (*vfs_unmounted_notify_fn)(void *, struct mount *,
228 EVENTHANDLER_DECLARE(vfs_mounted, vfs_mounted_notify_fn);
229 EVENTHANDLER_DECLARE(vfs_unmounted, vfs_unmounted_notify_fn);
233 * process_fork and exit handlers are called without Giant.
234 * exec handlers are called with Giant, but that is by accident.
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);
255 * application dump event
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, ...);
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);
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);
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);
281 /* Kernel linker file load and unload events */
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);
290 /* Generic graphics framebuffer interface */
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);
297 /* Veto ada attachment */
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);
304 /* Swap device events */
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);
311 /* newbus device events */
313 EVHDEV_DETACH_BEGIN, /* Before detach() is called */
314 EVHDEV_DETACH_COMPLETE, /* After detach() returns 0 */
315 EVHDEV_DETACH_FAILED /* After detach() returns err */
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);
324 /* Interface address addition and removal event */
326 typedef void (*rt_addrmsg_fn)(void *, struct ifaddr *, int);
327 EVENTHANDLER_DECLARE(rt_addrmsg, rt_addrmsg_fn);
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);
334 #endif /* _SYS_EVENTHANDLER_H_ */