Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | |
2 | /****************************************************************************** | |
3 | * | |
4 | * Module Name: exmutex - ASL Mutex Acquire/Release functions | |
5 | * | |
6 | *****************************************************************************/ | |
7 | ||
8 | /* | |
9 | * Copyright (C) 2000 - 2005, 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 | |
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 | /* Doubly linked list */ | |
77 | ||
78 | if (obj_desc->mutex.next) { | |
79 | (obj_desc->mutex.next)->mutex.prev = obj_desc->mutex.prev; | |
80 | } | |
81 | ||
82 | if (obj_desc->mutex.prev) { | |
83 | (obj_desc->mutex.prev)->mutex.next = obj_desc->mutex.next; | |
84 | } | |
85 | else { | |
86 | thread->acquired_mutex_list = obj_desc->mutex.next; | |
87 | } | |
88 | } | |
89 | ||
90 | ||
91 | /******************************************************************************* | |
92 | * | |
93 | * FUNCTION: acpi_ex_link_mutex | |
94 | * | |
95 | * PARAMETERS: obj_desc - The mutex to be linked | |
96 | * list_head - head of the "acquired_mutex" list | |
97 | * | |
98 | * RETURN: Status | |
99 | * | |
100 | * DESCRIPTION: Add a mutex to the "acquired_mutex" list for this walk | |
101 | * | |
102 | ******************************************************************************/ | |
103 | ||
104 | void | |
105 | acpi_ex_link_mutex ( | |
106 | union acpi_operand_object *obj_desc, | |
107 | struct acpi_thread_state *thread) | |
108 | { | |
109 | union acpi_operand_object *list_head; | |
110 | ||
111 | ||
112 | list_head = thread->acquired_mutex_list; | |
113 | ||
114 | /* This object will be the first object in the list */ | |
115 | ||
116 | obj_desc->mutex.prev = NULL; | |
117 | obj_desc->mutex.next = list_head; | |
118 | ||
119 | /* Update old first object to point back to this object */ | |
120 | ||
121 | if (list_head) { | |
122 | list_head->mutex.prev = obj_desc; | |
123 | } | |
124 | ||
125 | /* Update list head */ | |
126 | ||
127 | thread->acquired_mutex_list = obj_desc; | |
128 | } | |
129 | ||
130 | ||
131 | /******************************************************************************* | |
132 | * | |
133 | * FUNCTION: acpi_ex_acquire_mutex | |
134 | * | |
135 | * PARAMETERS: time_desc - The 'time to delay' object descriptor | |
136 | * obj_desc - The object descriptor for this op | |
137 | * | |
138 | * RETURN: Status | |
139 | * | |
140 | * DESCRIPTION: Acquire an AML mutex | |
141 | * | |
142 | ******************************************************************************/ | |
143 | ||
144 | acpi_status | |
145 | acpi_ex_acquire_mutex ( | |
146 | union acpi_operand_object *time_desc, | |
147 | union acpi_operand_object *obj_desc, | |
148 | struct acpi_walk_state *walk_state) | |
149 | { | |
150 | acpi_status status; | |
151 | ||
152 | ||
153 | ACPI_FUNCTION_TRACE_PTR ("ex_acquire_mutex", obj_desc); | |
154 | ||
155 | ||
156 | if (!obj_desc) { | |
157 | return_ACPI_STATUS (AE_BAD_PARAMETER); | |
158 | } | |
159 | ||
160 | /* Sanity check -- we must have a valid thread ID */ | |
161 | ||
162 | if (!walk_state->thread) { | |
163 | ACPI_REPORT_ERROR (("Cannot acquire Mutex [%4.4s], null thread info\n", | |
164 | acpi_ut_get_node_name (obj_desc->mutex.node))); | |
165 | return_ACPI_STATUS (AE_AML_INTERNAL); | |
166 | } | |
167 | ||
168 | /* | |
169 | * Current Sync must be less than or equal to the sync level of the | |
170 | * mutex. This mechanism provides some deadlock prevention | |
171 | */ | |
172 | if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) { | |
173 | ACPI_REPORT_ERROR (("Cannot acquire Mutex [%4.4s], incorrect sync_level\n", | |
174 | acpi_ut_get_node_name (obj_desc->mutex.node))); | |
175 | return_ACPI_STATUS (AE_AML_MUTEX_ORDER); | |
176 | } | |
177 | ||
178 | /* Support for multiple acquires by the owning thread */ | |
179 | ||
180 | if (obj_desc->mutex.owner_thread) { | |
181 | /* Special case for Global Lock, allow all threads */ | |
182 | ||
183 | if ((obj_desc->mutex.owner_thread->thread_id == walk_state->thread->thread_id) || | |
184 | (obj_desc->mutex.semaphore == acpi_gbl_global_lock_semaphore)) { | |
185 | /* | |
186 | * The mutex is already owned by this thread, | |
187 | * just increment the acquisition depth | |
188 | */ | |
189 | obj_desc->mutex.acquisition_depth++; | |
190 | return_ACPI_STATUS (AE_OK); | |
191 | } | |
192 | } | |
193 | ||
194 | /* Acquire the mutex, wait if necessary */ | |
195 | ||
196 | status = acpi_ex_system_acquire_mutex (time_desc, obj_desc); | |
197 | if (ACPI_FAILURE (status)) { | |
198 | /* Includes failure from a timeout on time_desc */ | |
199 | ||
200 | return_ACPI_STATUS (status); | |
201 | } | |
202 | ||
203 | /* Have the mutex: update mutex and walk info and save the sync_level */ | |
204 | ||
205 | obj_desc->mutex.owner_thread = walk_state->thread; | |
206 | obj_desc->mutex.acquisition_depth = 1; | |
207 | obj_desc->mutex.original_sync_level = walk_state->thread->current_sync_level; | |
208 | ||
209 | walk_state->thread->current_sync_level = obj_desc->mutex.sync_level; | |
210 | ||
211 | /* Link the mutex to the current thread for force-unlock at method exit */ | |
212 | ||
213 | acpi_ex_link_mutex (obj_desc, walk_state->thread); | |
214 | ||
215 | return_ACPI_STATUS (AE_OK); | |
216 | } | |
217 | ||
218 | ||
219 | /******************************************************************************* | |
220 | * | |
221 | * FUNCTION: acpi_ex_release_mutex | |
222 | * | |
223 | * PARAMETERS: obj_desc - The object descriptor for this op | |
224 | * | |
225 | * RETURN: Status | |
226 | * | |
227 | * DESCRIPTION: Release a previously acquired Mutex. | |
228 | * | |
229 | ******************************************************************************/ | |
230 | ||
231 | acpi_status | |
232 | acpi_ex_release_mutex ( | |
233 | union acpi_operand_object *obj_desc, | |
234 | struct acpi_walk_state *walk_state) | |
235 | { | |
236 | acpi_status status; | |
237 | ||
238 | ||
239 | ACPI_FUNCTION_TRACE ("ex_release_mutex"); | |
240 | ||
241 | ||
242 | if (!obj_desc) { | |
243 | return_ACPI_STATUS (AE_BAD_PARAMETER); | |
244 | } | |
245 | ||
246 | /* The mutex must have been previously acquired in order to release it */ | |
247 | ||
248 | if (!obj_desc->mutex.owner_thread) { | |
249 | ACPI_REPORT_ERROR (("Cannot release Mutex [%4.4s], not acquired\n", | |
250 | acpi_ut_get_node_name (obj_desc->mutex.node))); | |
251 | return_ACPI_STATUS (AE_AML_MUTEX_NOT_ACQUIRED); | |
252 | } | |
253 | ||
254 | /* Sanity check -- we must have a valid thread ID */ | |
255 | ||
256 | if (!walk_state->thread) { | |
257 | ACPI_REPORT_ERROR (("Cannot release Mutex [%4.4s], null thread info\n", | |
258 | acpi_ut_get_node_name (obj_desc->mutex.node))); | |
259 | return_ACPI_STATUS (AE_AML_INTERNAL); | |
260 | } | |
261 | ||
262 | /* | |
263 | * The Mutex is owned, but this thread must be the owner. | |
264 | * Special case for Global Lock, any thread can release | |
265 | */ | |
266 | if ((obj_desc->mutex.owner_thread->thread_id != walk_state->thread->thread_id) && | |
267 | (obj_desc->mutex.semaphore != acpi_gbl_global_lock_semaphore)) { | |
268 | ACPI_REPORT_ERROR (( | |
269 | "Thread %X cannot release Mutex [%4.4s] acquired by thread %X\n", | |
270 | walk_state->thread->thread_id, | |
271 | acpi_ut_get_node_name (obj_desc->mutex.node), | |
272 | obj_desc->mutex.owner_thread->thread_id)); | |
273 | return_ACPI_STATUS (AE_AML_NOT_OWNER); | |
274 | } | |
275 | ||
276 | /* | |
277 | * The sync level of the mutex must be less than or | |
278 | * equal to the current sync level | |
279 | */ | |
280 | if (obj_desc->mutex.sync_level > walk_state->thread->current_sync_level) { | |
281 | ACPI_REPORT_ERROR (("Cannot release Mutex [%4.4s], incorrect sync_level\n", | |
282 | acpi_ut_get_node_name (obj_desc->mutex.node))); | |
283 | return_ACPI_STATUS (AE_AML_MUTEX_ORDER); | |
284 | } | |
285 | ||
286 | /* Match multiple Acquires with multiple Releases */ | |
287 | ||
288 | obj_desc->mutex.acquisition_depth--; | |
289 | if (obj_desc->mutex.acquisition_depth != 0) { | |
290 | /* Just decrement the depth and return */ | |
291 | ||
292 | return_ACPI_STATUS (AE_OK); | |
293 | } | |
294 | ||
295 | /* Unlink the mutex from the owner's list */ | |
296 | ||
297 | acpi_ex_unlink_mutex (obj_desc); | |
298 | ||
299 | /* Release the mutex */ | |
300 | ||
301 | status = acpi_ex_system_release_mutex (obj_desc); | |
302 | ||
303 | /* Update the mutex and walk state, restore sync_level before acquire */ | |
304 | ||
305 | obj_desc->mutex.owner_thread = NULL; | |
306 | walk_state->thread->current_sync_level = obj_desc->mutex.original_sync_level; | |
307 | ||
308 | return_ACPI_STATUS (status); | |
309 | } | |
310 | ||
311 | ||
312 | /******************************************************************************* | |
313 | * | |
314 | * FUNCTION: acpi_ex_release_all_mutexes | |
315 | * | |
316 | * PARAMETERS: mutex_list - Head of the mutex list | |
317 | * | |
318 | * RETURN: Status | |
319 | * | |
320 | * DESCRIPTION: Release all mutexes in the list | |
321 | * | |
322 | ******************************************************************************/ | |
323 | ||
324 | void | |
325 | acpi_ex_release_all_mutexes ( | |
326 | struct acpi_thread_state *thread) | |
327 | { | |
328 | union acpi_operand_object *next = thread->acquired_mutex_list; | |
329 | union acpi_operand_object *this; | |
330 | acpi_status status; | |
331 | ||
332 | ||
333 | ACPI_FUNCTION_ENTRY (); | |
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 | /* Update Thread sync_level (Last mutex is the important one) */ | |
358 | ||
359 | thread->current_sync_level = this->mutex.original_sync_level; | |
360 | } | |
361 | } | |
362 | ||
363 |