1 /*
2 * Copyright (c) 2000-2020 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /*
29 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
30 *
31 * HISTORY
32 *
33 * 29 June 2000 (debo)
34 * Created.
35 */
36
37 #include <mach/mach_types.h>
38 #include <mach/mach_traps.h>
39 #include <mach/mach_port_server.h>
40
41 #include <mach/mk_timer.h>
42
43 #include <ipc/ipc_space.h>
44
45 #include <kern/lock_group.h>
46 #include <kern/thread_call.h>
47 #include <ipc/ipc_kmsg.h>
48
49 struct mk_timer {
50 decl_simple_lock_data(, lock);
51 thread_call_data_t mkt_thread_call;
52 uint32_t is_dead:1,
53 is_armed:1;
54 int active;
55 ipc_port_t port;
56 };
57
58 static ZONE_DEFINE_TYPE(mk_timer_zone, "mk_timer",
59 struct mk_timer, ZC_ZFREE_CLEARMEM);
60
61 static void mk_timer_port_destroy(ipc_port_t);
62 static void mk_timer_expire(void *p0, void *p1);
63
64 IPC_KOBJECT_DEFINE(IKOT_TIMER,
65 .iko_op_destroy = mk_timer_port_destroy);
66
67 __abortlike
68 static void
ipc_kobject_mktimer_require_panic(ipc_port_t port)69 ipc_kobject_mktimer_require_panic(
70 ipc_port_t port)
71 {
72 panic("port %p / mktimer %p: circularity check failed",
73 port, ipc_kobject_get_raw(port, IKOT_TIMER));
74 }
75
76 void
ipc_kobject_mktimer_require_locked(ipc_port_t port)77 ipc_kobject_mktimer_require_locked(
78 ipc_port_t port)
79 {
80 struct mk_timer *timer;
81
82 timer = ipc_kobject_get_locked(port, IKOT_TIMER);
83 if (timer->port != port) {
84 ipc_kobject_mktimer_require_panic(port);
85 }
86 }
87
88 mach_port_name_t
mk_timer_create_trap(__unused struct mk_timer_create_trap_args * args)89 mk_timer_create_trap(
90 __unused struct mk_timer_create_trap_args *args)
91 {
92 struct mk_timer* timer;
93 ipc_space_t myspace = current_space();
94 mach_port_name_t name = MACH_PORT_NULL;
95 ipc_port_init_flags_t init_flags;
96 ipc_port_t port;
97 kern_return_t result;
98 ipc_kmsg_t kmsg;
99
100 /* Allocate and initialize local state of a timer object */
101 timer = zalloc_flags(mk_timer_zone, Z_ZERO | Z_WAITOK | Z_NOFAIL);
102 simple_lock_init(&timer->lock, 0);
103 thread_call_setup(&timer->mkt_thread_call, mk_timer_expire, timer);
104
105 /* Pre-allocate a kmsg for the timer messages */
106 kmsg = ipc_kmsg_alloc(sizeof(mk_timer_expire_msg_t), 0, 0,
107 IPC_KMSG_ALLOC_KERNEL | IPC_KMSG_ALLOC_ZERO |
108 IPC_KMSG_ALLOC_SAVED | IPC_KMSG_ALLOC_NOFAIL);
109
110 init_flags = IPC_PORT_INIT_MESSAGE_QUEUE;
111 result = ipc_port_alloc(myspace, init_flags, &name, &port);
112 if (result != KERN_SUCCESS) {
113 zfree(mk_timer_zone, timer);
114 ipc_kmsg_free(kmsg);
115 return MACH_PORT_NULL;
116 }
117
118 /* Associate the pre-allocated kmsg with the port */
119 ipc_kmsg_set_prealloc(kmsg, port);
120
121 /* port locked, receive right at user-space */
122 ipc_kobject_upgrade_mktimer_locked(port, (ipc_kobject_t)timer);
123
124 /* make a (naked) send right for the timer to keep */
125 timer->port = ipc_port_make_send_any_locked(port);
126
127 ip_mq_unlock(port);
128
129 return name;
130 }
131
132 static void
mk_timer_port_destroy(ipc_port_t port)133 mk_timer_port_destroy(
134 ipc_port_t port)
135 {
136 struct mk_timer *timer = NULL;
137
138 timer = ipc_kobject_disable(port, IKOT_TIMER);
139
140 simple_lock(&timer->lock, LCK_GRP_NULL);
141
142 if (thread_call_cancel(&timer->mkt_thread_call)) {
143 timer->active--;
144 }
145 timer->is_armed = FALSE;
146
147 timer->is_dead = TRUE;
148 if (timer->active == 0) {
149 simple_unlock(&timer->lock);
150 zfree(mk_timer_zone, timer);
151
152 ipc_port_release_send(port);
153 return;
154 }
155
156 simple_unlock(&timer->lock);
157 }
158
159 static void
mk_timer_expire(void * p0,__unused void * p1)160 mk_timer_expire(
161 void *p0,
162 __unused void *p1)
163 {
164 struct mk_timer* timer = p0;
165
166 simple_lock(&timer->lock, LCK_GRP_NULL);
167
168 if (timer->active > 1) {
169 timer->active--;
170 simple_unlock(&timer->lock);
171 return;
172 }
173
174 ipc_port_t port = timer->port;
175 assert(port != IP_NULL);
176 assert(timer->active == 1);
177
178 while (timer->is_armed && timer->active == 1) {
179 mk_timer_expire_msg_t msg;
180
181 timer->is_armed = FALSE;
182 simple_unlock(&timer->lock);
183
184 msg.header.msgh_bits =
185 MACH_MSGH_BITS_SET(MACH_MSG_TYPE_COPY_SEND, 0, 0, 0);
186 msg.header.msgh_remote_port = port;
187 msg.header.msgh_local_port = MACH_PORT_NULL;
188 msg.header.msgh_voucher_port = MACH_PORT_NULL;
189 msg.header.msgh_id = 0;
190
191 msg.unused[0] = msg.unused[1] = msg.unused[2] = 0;
192
193 (void) mach_msg_send_from_kernel_proper(&msg.header, sizeof(msg));
194
195 simple_lock(&timer->lock, LCK_GRP_NULL);
196 }
197
198 if (--timer->active == 0 && timer->is_dead) {
199 simple_unlock(&timer->lock);
200 zfree(mk_timer_zone, timer);
201
202 ipc_port_release_send(port);
203 return;
204 }
205
206 simple_unlock(&timer->lock);
207 }
208
209 /*
210 * mk_timer_destroy_trap: Destroy the Mach port associated with a timer
211 *
212 * Parameters: args User argument descriptor (see below)
213 *
214 * Indirect: args->name Mach port name
215 *
216 *
217 * Returns: 0 Success
218 * !0 Not success
219 *
220 */
221 kern_return_t
mk_timer_destroy_trap(struct mk_timer_destroy_trap_args * args)222 mk_timer_destroy_trap(
223 struct mk_timer_destroy_trap_args *args)
224 {
225 mach_port_name_t name = args->name;
226 ipc_space_t myspace = current_space();
227 ipc_port_t port;
228 kern_return_t result;
229
230 result = ipc_port_translate_receive(myspace, name, &port);
231 if (result != KERN_SUCCESS) {
232 return result;
233 }
234
235 if (ip_kotype(port) == IKOT_TIMER) {
236 ip_mq_unlock(port);
237 /* TODO: this should be mach_port_mod_refs */
238 result = mach_port_destroy(myspace, name);
239 } else {
240 ip_mq_unlock(port);
241 result = KERN_INVALID_ARGUMENT;
242 }
243
244 return result;
245 }
246
247 /*
248 * mk_timer_arm_trap: Start (arm) a timer
249 *
250 * Parameters: args User argument descriptor (see below)
251 *
252 * Indirect: args->name Mach port name
253 * args->expire_time Time when timer expires
254 *
255 *
256 * Returns: 0 Success
257 * !0 Not success
258 *
259 */
260
261 static kern_return_t
mk_timer_arm_trap_internal(mach_port_name_t name,uint64_t expire_time,uint64_t mk_leeway,uint64_t mk_timer_flags)262 mk_timer_arm_trap_internal(mach_port_name_t name, uint64_t expire_time, uint64_t mk_leeway, uint64_t mk_timer_flags)
263 {
264 struct mk_timer* timer;
265 ipc_space_t myspace = current_space();
266 ipc_port_t port;
267 kern_return_t result;
268
269 result = ipc_port_translate_receive(myspace, name, &port);
270 if (result != KERN_SUCCESS) {
271 return result;
272 }
273
274 timer = ipc_kobject_get_locked(port, IKOT_TIMER);
275
276 if (timer) {
277
278 simple_lock(&timer->lock, LCK_GRP_NULL);
279 assert(timer->port == port);
280 ip_mq_unlock(port);
281
282 if (!timer->is_dead) {
283 timer->is_armed = TRUE;
284
285 if (expire_time > mach_absolute_time()) {
286 uint32_t tcflags = THREAD_CALL_DELAY_USER_NORMAL;
287
288 if (mk_timer_flags & MK_TIMER_CRITICAL) {
289 tcflags = THREAD_CALL_DELAY_USER_CRITICAL;
290 }
291
292 if (mk_leeway != 0) {
293 tcflags |= THREAD_CALL_DELAY_LEEWAY;
294 }
295
296 if (!thread_call_enter_delayed_with_leeway(
297 &timer->mkt_thread_call, NULL,
298 expire_time, mk_leeway, tcflags)) {
299 timer->active++;
300 }
301 } else {
302 if (!thread_call_enter1(&timer->mkt_thread_call, NULL)) {
303 timer->active++;
304 }
305 }
306 }
307
308 simple_unlock(&timer->lock);
309 } else {
310 ip_mq_unlock(port);
311 result = KERN_INVALID_ARGUMENT;
312 }
313 return result;
314 }
315
316 kern_return_t
mk_timer_arm_trap(struct mk_timer_arm_trap_args * args)317 mk_timer_arm_trap(struct mk_timer_arm_trap_args *args)
318 {
319 return mk_timer_arm_trap_internal(args->name, args->expire_time, 0, MK_TIMER_NORMAL);
320 }
321
322 kern_return_t
mk_timer_arm_leeway_trap(struct mk_timer_arm_leeway_trap_args * args)323 mk_timer_arm_leeway_trap(struct mk_timer_arm_leeway_trap_args *args)
324 {
325 return mk_timer_arm_trap_internal(args->name, args->expire_time, args->mk_leeway, args->mk_timer_flags);
326 }
327
328 /*
329 * mk_timer_cancel_trap: Cancel a timer
330 *
331 * Parameters: args User argument descriptor (see below)
332 *
333 * Indirect: args->name Mach port name
334 * args->result_time The armed time of the cancelled timer (return value)
335 *
336 *
337 * Returns: 0 Success
338 * !0 Not success
339 *
340 */
341 kern_return_t
mk_timer_cancel_trap(struct mk_timer_cancel_trap_args * args)342 mk_timer_cancel_trap(
343 struct mk_timer_cancel_trap_args *args)
344 {
345 mach_port_name_t name = args->name;
346 mach_vm_address_t result_time_addr = args->result_time;
347 uint64_t armed_time = 0;
348 struct mk_timer* timer;
349 ipc_space_t myspace = current_space();
350 ipc_port_t port;
351 kern_return_t result;
352
353 result = ipc_port_translate_receive(myspace, name, &port);
354 if (result != KERN_SUCCESS) {
355 return result;
356 }
357
358 timer = ipc_kobject_get_locked(port, IKOT_TIMER);
359 if (timer != NULL) {
360 simple_lock(&timer->lock, LCK_GRP_NULL);
361 assert(timer->port == port);
362 ip_mq_unlock(port);
363
364 if (timer->is_armed) {
365 armed_time = thread_call_get_armed_deadline(&timer->mkt_thread_call);
366 if (thread_call_cancel(&timer->mkt_thread_call)) {
367 timer->active--;
368 }
369 timer->is_armed = FALSE;
370 }
371
372 simple_unlock(&timer->lock);
373 } else {
374 ip_mq_unlock(port);
375 result = KERN_INVALID_ARGUMENT;
376 }
377
378 if (result == KERN_SUCCESS && result_time_addr != 0) {
379 if (copyout((void *)&armed_time, result_time_addr, sizeof(armed_time)) != 0) {
380 result = KERN_FAILURE;
381 }
382 }
383
384 return result;
385 }
386