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 static_assert(sizeof(mk_timer_expire_msg_t) < IKM_SAVED_MSG_SIZE);
110
111 init_flags = IPC_PORT_INIT_MESSAGE_QUEUE;
112 result = ipc_port_alloc(myspace, init_flags, &name, &port);
113 if (result != KERN_SUCCESS) {
114 zfree(mk_timer_zone, timer);
115 ipc_kmsg_free(kmsg);
116 return MACH_PORT_NULL;
117 }
118
119 /* Associate the pre-allocated kmsg with the port */
120 ipc_kmsg_set_prealloc(kmsg, port);
121
122 /* port locked, receive right at user-space */
123 ipc_kobject_upgrade_mktimer_locked(port, (ipc_kobject_t)timer);
124
125 /* make a (naked) send right for the timer to keep */
126 timer->port = ipc_port_make_send_any_locked(port);
127
128 ip_mq_unlock(port);
129
130 return name;
131 }
132
133 static void
mk_timer_port_destroy(ipc_port_t port)134 mk_timer_port_destroy(
135 ipc_port_t port)
136 {
137 struct mk_timer *timer = NULL;
138
139 timer = ipc_kobject_disable(port, IKOT_TIMER);
140
141 simple_lock(&timer->lock, LCK_GRP_NULL);
142
143 if (thread_call_cancel(&timer->mkt_thread_call)) {
144 timer->active--;
145 }
146 timer->is_armed = FALSE;
147
148 timer->is_dead = TRUE;
149 if (timer->active == 0) {
150 simple_unlock(&timer->lock);
151 zfree(mk_timer_zone, timer);
152
153 ipc_port_release_send(port);
154 return;
155 }
156
157 simple_unlock(&timer->lock);
158 }
159
160 static void
mk_timer_expire(void * p0,__unused void * p1)161 mk_timer_expire(
162 void *p0,
163 __unused void *p1)
164 {
165 struct mk_timer* timer = p0;
166
167 simple_lock(&timer->lock, LCK_GRP_NULL);
168
169 if (timer->active > 1) {
170 timer->active--;
171 simple_unlock(&timer->lock);
172 return;
173 }
174
175 ipc_port_t port = timer->port;
176 assert(port != IP_NULL);
177 assert(timer->active == 1);
178
179 while (timer->is_armed && timer->active == 1) {
180 mk_timer_expire_msg_t msg;
181
182 timer->is_armed = FALSE;
183 simple_unlock(&timer->lock);
184
185 msg.header.msgh_bits =
186 MACH_MSGH_BITS_SET(MACH_MSG_TYPE_COPY_SEND, 0, 0, 0);
187 msg.header.msgh_remote_port = port;
188 msg.header.msgh_local_port = MACH_PORT_NULL;
189 msg.header.msgh_voucher_port = MACH_PORT_NULL;
190 msg.header.msgh_id = 0;
191
192 msg.unused[0] = msg.unused[1] = msg.unused[2] = 0;
193
194 (void) mach_msg_send_from_kernel_proper(&msg.header, sizeof(msg));
195
196 simple_lock(&timer->lock, LCK_GRP_NULL);
197 }
198
199 if (--timer->active == 0 && timer->is_dead) {
200 simple_unlock(&timer->lock);
201 zfree(mk_timer_zone, timer);
202
203 ipc_port_release_send(port);
204 return;
205 }
206
207 simple_unlock(&timer->lock);
208 }
209
210 /*
211 * mk_timer_destroy_trap: Destroy the Mach port associated with a timer
212 *
213 * Parameters: args User argument descriptor (see below)
214 *
215 * Indirect: args->name Mach port name
216 *
217 *
218 * Returns: 0 Success
219 * !0 Not success
220 *
221 */
222 kern_return_t
mk_timer_destroy_trap(struct mk_timer_destroy_trap_args * args)223 mk_timer_destroy_trap(
224 struct mk_timer_destroy_trap_args *args)
225 {
226 mach_port_name_t name = args->name;
227 ipc_space_t myspace = current_space();
228 ipc_port_t port;
229 kern_return_t result;
230
231 result = ipc_port_translate_receive(myspace, name, &port);
232 if (result != KERN_SUCCESS) {
233 return result;
234 }
235
236 if (ip_kotype(port) == IKOT_TIMER) {
237 ip_mq_unlock(port);
238 /* TODO: this should be mach_port_mod_refs */
239 result = mach_port_destroy(myspace, name);
240 } else {
241 ip_mq_unlock(port);
242 result = KERN_INVALID_ARGUMENT;
243 }
244
245 return result;
246 }
247
248 /*
249 * mk_timer_arm_trap: Start (arm) a timer
250 *
251 * Parameters: args User argument descriptor (see below)
252 *
253 * Indirect: args->name Mach port name
254 * args->expire_time Time when timer expires
255 *
256 *
257 * Returns: 0 Success
258 * !0 Not success
259 *
260 */
261
262 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)263 mk_timer_arm_trap_internal(mach_port_name_t name, uint64_t expire_time, uint64_t mk_leeway, uint64_t mk_timer_flags)
264 {
265 struct mk_timer* timer;
266 ipc_space_t myspace = current_space();
267 ipc_port_t port;
268 kern_return_t result;
269
270 result = ipc_port_translate_receive(myspace, name, &port);
271 if (result != KERN_SUCCESS) {
272 return result;
273 }
274
275 timer = ipc_kobject_get_locked(port, IKOT_TIMER);
276
277 if (timer) {
278
279 simple_lock(&timer->lock, LCK_GRP_NULL);
280 assert(timer->port == port);
281 ip_mq_unlock(port);
282
283 if (!timer->is_dead) {
284 timer->is_armed = TRUE;
285
286 if (expire_time > mach_absolute_time()) {
287 uint32_t tcflags = THREAD_CALL_DELAY_USER_NORMAL;
288
289 if (mk_timer_flags & MK_TIMER_CRITICAL) {
290 tcflags = THREAD_CALL_DELAY_USER_CRITICAL;
291 }
292
293 if (mk_leeway != 0) {
294 tcflags |= THREAD_CALL_DELAY_LEEWAY;
295 }
296
297 if (!thread_call_enter_delayed_with_leeway(
298 &timer->mkt_thread_call, NULL,
299 expire_time, mk_leeway, tcflags)) {
300 timer->active++;
301 }
302 } else {
303 if (!thread_call_enter1(&timer->mkt_thread_call, NULL)) {
304 timer->active++;
305 }
306 }
307 }
308
309 simple_unlock(&timer->lock);
310 } else {
311 ip_mq_unlock(port);
312 result = KERN_INVALID_ARGUMENT;
313 }
314 return result;
315 }
316
317 kern_return_t
mk_timer_arm_trap(struct mk_timer_arm_trap_args * args)318 mk_timer_arm_trap(struct mk_timer_arm_trap_args *args)
319 {
320 return mk_timer_arm_trap_internal(args->name, args->expire_time, 0, MK_TIMER_NORMAL);
321 }
322
323 kern_return_t
mk_timer_arm_leeway_trap(struct mk_timer_arm_leeway_trap_args * args)324 mk_timer_arm_leeway_trap(struct mk_timer_arm_leeway_trap_args *args)
325 {
326 return mk_timer_arm_trap_internal(args->name, args->expire_time, args->mk_leeway, args->mk_timer_flags);
327 }
328
329 /*
330 * mk_timer_cancel_trap: Cancel a timer
331 *
332 * Parameters: args User argument descriptor (see below)
333 *
334 * Indirect: args->name Mach port name
335 * args->result_time The armed time of the cancelled timer (return value)
336 *
337 *
338 * Returns: 0 Success
339 * !0 Not success
340 *
341 */
342 kern_return_t
mk_timer_cancel_trap(struct mk_timer_cancel_trap_args * args)343 mk_timer_cancel_trap(
344 struct mk_timer_cancel_trap_args *args)
345 {
346 mach_port_name_t name = args->name;
347 mach_vm_address_t result_time_addr = args->result_time;
348 uint64_t armed_time = 0;
349 struct mk_timer* timer;
350 ipc_space_t myspace = current_space();
351 ipc_port_t port;
352 kern_return_t result;
353
354 result = ipc_port_translate_receive(myspace, name, &port);
355 if (result != KERN_SUCCESS) {
356 return result;
357 }
358
359 timer = ipc_kobject_get_locked(port, IKOT_TIMER);
360 if (timer != NULL) {
361 simple_lock(&timer->lock, LCK_GRP_NULL);
362 assert(timer->port == port);
363 ip_mq_unlock(port);
364
365 if (timer->is_armed) {
366 armed_time = thread_call_get_armed_deadline(&timer->mkt_thread_call);
367 if (thread_call_cancel(&timer->mkt_thread_call)) {
368 timer->active--;
369 }
370 timer->is_armed = FALSE;
371 }
372
373 simple_unlock(&timer->lock);
374 } else {
375 ip_mq_unlock(port);
376 result = KERN_INVALID_ARGUMENT;
377 }
378
379 if (result == KERN_SUCCESS && result_time_addr != 0) {
380 if (copyout((void *)&armed_time, result_time_addr, sizeof(armed_time)) != 0) {
381 result = KERN_FAILURE;
382 }
383 }
384
385 return result;
386 }
387