1
2 /******************************************************************************
3 *
4 * Module Name: exmutex - ASL Mutex Acquire/Release functions
5 *
6 *****************************************************************************/
7
8 /*
9 * Copyright (C) 2000 - 2004, R. Byron Moore
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 * substantially similar to the "NO WARRANTY" disclaimer below
20 * ("Disclaimer") and any redistribution must be conditioned upon
21 * including a substantially similar Disclaimer requirement for further
22 * binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 * of any contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
30 *
31 * NO WARRANTY
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGES.
43 */
44
45
46 #include <acpi/acpi.h>
47 #include <acpi/acinterp.h>
48
49 #define _COMPONENT ACPI_EXECUTER
50 ACPI_MODULE_NAME ("exmutex")
51
52
53 /*******************************************************************************
54 *
55 * FUNCTION: acpi_ex_unlink_mutex
56 *
57 * PARAMETERS: *obj_desc - The mutex to be unlinked
58 *
59 * RETURN: Status
60 *
61 * DESCRIPTION: Remove a mutex from the "acquired_mutex" list
62 *
63 ******************************************************************************/
64
65 void
acpi_ex_unlink_mutex(union acpi_operand_object * obj_desc)66 acpi_ex_unlink_mutex (
67 union acpi_operand_object *obj_desc)
68 {
69 struct acpi_thread_state *thread = obj_desc->mutex.owner_thread;
70
71
72 if (!thread) {
73 return;
74 }
75
76 if (obj_desc->mutex.next) {
77 (obj_desc->mutex.next)->mutex.prev = obj_desc->mutex.prev;
78 }
79
80 if (obj_desc->mutex.prev) {
81 (obj_desc->mutex.prev)->mutex.next = obj_desc->mutex.next;
82 }
83 else {
84 thread->acquired_mutex_list = obj_desc->mutex.next;
85 }
86 }
87
88
89 /*******************************************************************************
90 *
91 * FUNCTION: acpi_ex_link_mutex
92 *
93 * PARAMETERS: *obj_desc - The mutex to be linked
94 * *list_head - head of the "acquired_mutex" list
95 *
96 * RETURN: Status
97 *
98 * DESCRIPTION: Add a mutex to the "acquired_mutex" list for this walk
99 *
100 ******************************************************************************/
101
102 void
acpi_ex_link_mutex(union acpi_operand_object * obj_desc,struct acpi_thread_state * thread)103 acpi_ex_link_mutex (
104 union acpi_operand_object *obj_desc,
105 struct acpi_thread_state *thread)
106 {
107 union acpi_operand_object *list_head;
108
109
110 list_head = thread->acquired_mutex_list;
111
112 /* This object will be the first object in the list */
113
114 obj_desc->mutex.prev = NULL;
115 obj_desc->mutex.next = list_head;
116
117 /* Update old first object to point back to this object */
118
119 if (list_head) {
120 list_head->mutex.prev = obj_desc;
121 }
122
123 /* Update list head */
124
125 thread->acquired_mutex_list = obj_desc;
126 }
127
128
129 /*******************************************************************************
130 *
131 * FUNCTION: acpi_ex_acquire_mutex
132 *
133 * PARAMETERS: *time_desc - The 'time to delay' object descriptor
134 * *obj_desc - The object descriptor for this op
135 *
136 * RETURN: Status
137 *
138 * DESCRIPTION: Acquire an AML mutex
139 *
140 ******************************************************************************/
141
142 acpi_status
acpi_ex_acquire_mutex(union acpi_operand_object * time_desc,union acpi_operand_object * obj_desc,struct acpi_walk_state * walk_state)143 acpi_ex_acquire_mutex (
144 union acpi_operand_object *time_desc,
145 union acpi_operand_object *obj_desc,
146 struct acpi_walk_state *walk_state)
147 {
148 acpi_status status;
149
150
151 ACPI_FUNCTION_TRACE_PTR ("ex_acquire_mutex", obj_desc);
152
153
154 if (!obj_desc) {
155 return_ACPI_STATUS (AE_BAD_PARAMETER);
156 }
157
158 /* Sanity check -- we must have a valid thread ID */
159
160 if (!walk_state->thread) {
161 ACPI_REPORT_ERROR (("Cannot acquire Mutex [%4.4s], null thread info\n",
162 acpi_ut_get_node_name (obj_desc->mutex.node)));
163 return_ACPI_STATUS (AE_AML_INTERNAL);
164 }
165
166 /*
167 * Current Sync must be less than or equal to the sync level of the
168 * mutex. This mechanism provides some deadlock prevention
169 */
170 if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) {
171 ACPI_REPORT_ERROR (("Cannot acquire Mutex [%4.4s], incorrect sync_level\n",
172 acpi_ut_get_node_name (obj_desc->mutex.node)));
173 return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
174 }
175
176 /*
177 * Support for multiple acquires by the owning thread
178 */
179 if (obj_desc->mutex.owner_thread) {
180 /* Special case for Global Lock, allow all threads */
181
182 if ((obj_desc->mutex.owner_thread->thread_id == walk_state->thread->thread_id) ||
183 (obj_desc->mutex.semaphore == acpi_gbl_global_lock_semaphore)) {
184 /*
185 * The mutex is already owned by this thread,
186 * just increment the acquisition depth
187 */
188 obj_desc->mutex.acquisition_depth++;
189 return_ACPI_STATUS (AE_OK);
190 }
191 }
192
193 /* Acquire the mutex, wait if necessary */
194
195 status = acpi_ex_system_acquire_mutex (time_desc, obj_desc);
196 if (ACPI_FAILURE (status)) {
197 /* Includes failure from a timeout on time_desc */
198
199 return_ACPI_STATUS (status);
200 }
201
202 /* Have the mutex, update mutex and walk info */
203
204 obj_desc->mutex.owner_thread = walk_state->thread;
205 obj_desc->mutex.acquisition_depth = 1;
206
207 walk_state->thread->current_sync_level = obj_desc->mutex.sync_level;
208
209 /* Link the mutex to the current thread for force-unlock at method exit */
210
211 acpi_ex_link_mutex (obj_desc, walk_state->thread);
212
213 return_ACPI_STATUS (AE_OK);
214 }
215
216
217 /*******************************************************************************
218 *
219 * FUNCTION: acpi_ex_release_mutex
220 *
221 * PARAMETERS: *obj_desc - The object descriptor for this op
222 *
223 * RETURN: Status
224 *
225 * DESCRIPTION: Release a previously acquired Mutex.
226 *
227 ******************************************************************************/
228
229 acpi_status
acpi_ex_release_mutex(union acpi_operand_object * obj_desc,struct acpi_walk_state * walk_state)230 acpi_ex_release_mutex (
231 union acpi_operand_object *obj_desc,
232 struct acpi_walk_state *walk_state)
233 {
234 acpi_status status;
235
236
237 ACPI_FUNCTION_TRACE ("ex_release_mutex");
238
239
240 if (!obj_desc) {
241 return_ACPI_STATUS (AE_BAD_PARAMETER);
242 }
243
244 /* The mutex must have been previously acquired in order to release it */
245
246 if (!obj_desc->mutex.owner_thread) {
247 ACPI_REPORT_ERROR (("Cannot release Mutex [%4.4s], not acquired\n",
248 acpi_ut_get_node_name (obj_desc->mutex.node)));
249 return_ACPI_STATUS (AE_AML_MUTEX_NOT_ACQUIRED);
250 }
251
252 /* Sanity check -- we must have a valid thread ID */
253
254 if (!walk_state->thread) {
255 ACPI_REPORT_ERROR (("Cannot release Mutex [%4.4s], null thread info\n",
256 acpi_ut_get_node_name (obj_desc->mutex.node)));
257 return_ACPI_STATUS (AE_AML_INTERNAL);
258 }
259
260 /*
261 * The Mutex is owned, but this thread must be the owner.
262 * Special case for Global Lock, any thread can release
263 */
264 if ((obj_desc->mutex.owner_thread->thread_id != walk_state->thread->thread_id) &&
265 (obj_desc->mutex.semaphore != acpi_gbl_global_lock_semaphore)) {
266 ACPI_REPORT_ERROR ((
267 "Thread %X cannot release Mutex [%4.4s] acquired by thread %X\n",
268 walk_state->thread->thread_id,
269 acpi_ut_get_node_name (obj_desc->mutex.node),
270 obj_desc->mutex.owner_thread->thread_id));
271 return_ACPI_STATUS (AE_AML_NOT_OWNER);
272 }
273
274 /*
275 * The sync level of the mutex must be less than or
276 * equal to the current sync level
277 */
278 if (obj_desc->mutex.sync_level > walk_state->thread->current_sync_level) {
279 ACPI_REPORT_ERROR (("Cannot release Mutex [%4.4s], incorrect sync_level\n",
280 acpi_ut_get_node_name (obj_desc->mutex.node)));
281 return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
282 }
283
284 /*
285 * Match multiple Acquires with multiple Releases
286 */
287 obj_desc->mutex.acquisition_depth--;
288 if (obj_desc->mutex.acquisition_depth != 0) {
289 /* Just decrement the depth and return */
290
291 return_ACPI_STATUS (AE_OK);
292 }
293
294 /* Unlink the mutex from the owner's list */
295
296 acpi_ex_unlink_mutex (obj_desc);
297
298 /* Release the mutex */
299
300 status = acpi_ex_system_release_mutex (obj_desc);
301
302 /* Update the mutex and walk state */
303
304 obj_desc->mutex.owner_thread = NULL;
305 walk_state->thread->current_sync_level = obj_desc->mutex.sync_level;
306
307 return_ACPI_STATUS (status);
308 }
309
310
311 /*******************************************************************************
312 *
313 * FUNCTION: acpi_ex_release_all_mutexes
314 *
315 * PARAMETERS: *mutex_list - Head of the mutex list
316 *
317 * RETURN: Status
318 *
319 * DESCRIPTION: Release all mutexes in the list
320 *
321 ******************************************************************************/
322
323 void
acpi_ex_release_all_mutexes(struct acpi_thread_state * thread)324 acpi_ex_release_all_mutexes (
325 struct acpi_thread_state *thread)
326 {
327 union acpi_operand_object *next = thread->acquired_mutex_list;
328 union acpi_operand_object *this;
329 acpi_status status;
330
331
332 ACPI_FUNCTION_ENTRY ();
333
334
335 /*
336 * Traverse the list of owned mutexes, releasing each one.
337 */
338 while (next) {
339 this = next;
340 next = this->mutex.next;
341
342 this->mutex.acquisition_depth = 1;
343 this->mutex.prev = NULL;
344 this->mutex.next = NULL;
345
346 /* Release the mutex */
347
348 status = acpi_ex_system_release_mutex (this);
349 if (ACPI_FAILURE (status)) {
350 continue;
351 }
352
353 /* Mark mutex unowned */
354
355 this->mutex.owner_thread = NULL;
356 }
357 }
358
359
360