1
2 /******************************************************************************
3 *
4 * Module Name: exmutex - ASL Mutex Acquire/Release functions
5 *
6 *****************************************************************************/
7
8 /*
9 * Copyright (C) 2000 - 2008, Intel Corp.
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 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "acinterp.h"
48 #include "acevents.h"
49
50 #define _COMPONENT ACPI_EXECUTER
51 ACPI_MODULE_NAME("exmutex")
52
53 /* Local prototypes */
54 static void
55 acpi_ex_link_mutex(union acpi_operand_object *obj_desc,
56 struct acpi_thread_state *thread);
57
58 /*******************************************************************************
59 *
60 * FUNCTION: acpi_ex_unlink_mutex
61 *
62 * PARAMETERS: obj_desc - The mutex to be unlinked
63 *
64 * RETURN: None
65 *
66 * DESCRIPTION: Remove a mutex from the "AcquiredMutex" list
67 *
68 ******************************************************************************/
69
acpi_ex_unlink_mutex(union acpi_operand_object * obj_desc)70 void acpi_ex_unlink_mutex(union acpi_operand_object *obj_desc)
71 {
72 struct acpi_thread_state *thread = obj_desc->mutex.owner_thread;
73
74 if (!thread) {
75 return;
76 }
77
78 /* Doubly linked list */
79
80 if (obj_desc->mutex.next) {
81 (obj_desc->mutex.next)->mutex.prev = obj_desc->mutex.prev;
82 }
83
84 if (obj_desc->mutex.prev) {
85 (obj_desc->mutex.prev)->mutex.next = obj_desc->mutex.next;
86 } else {
87 thread->acquired_mutex_list = obj_desc->mutex.next;
88 }
89 }
90
91 /*******************************************************************************
92 *
93 * FUNCTION: acpi_ex_link_mutex
94 *
95 * PARAMETERS: obj_desc - The mutex to be linked
96 * Thread - Current executing thread object
97 *
98 * RETURN: None
99 *
100 * DESCRIPTION: Add a mutex to the "AcquiredMutex" list for this walk
101 *
102 ******************************************************************************/
103
104 static void
acpi_ex_link_mutex(union acpi_operand_object * obj_desc,struct acpi_thread_state * thread)105 acpi_ex_link_mutex(union acpi_operand_object *obj_desc,
106 struct acpi_thread_state *thread)
107 {
108 union acpi_operand_object *list_head;
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 * FUNCTION: acpi_ex_acquire_mutex_object
131 *
132 * PARAMETERS: time_desc - Timeout in milliseconds
133 * obj_desc - Mutex object
134 * Thread - Current thread state
135 *
136 * RETURN: Status
137 *
138 * DESCRIPTION: Acquire an AML mutex, low-level interface. Provides a common
139 * path that supports multiple acquires by the same thread.
140 *
141 * MUTEX: Interpreter must be locked
142 *
143 * NOTE: This interface is called from three places:
144 * 1) From acpi_ex_acquire_mutex, via an AML Acquire() operator
145 * 2) From acpi_ex_acquire_global_lock when an AML Field access requires the
146 * global lock
147 * 3) From the external interface, acpi_acquire_global_lock
148 *
149 ******************************************************************************/
150
151 acpi_status
acpi_ex_acquire_mutex_object(u16 timeout,union acpi_operand_object * obj_desc,acpi_thread_id thread_id)152 acpi_ex_acquire_mutex_object(u16 timeout,
153 union acpi_operand_object *obj_desc,
154 acpi_thread_id thread_id)
155 {
156 acpi_status status;
157
158 ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex_object, obj_desc);
159
160 if (!obj_desc) {
161 return_ACPI_STATUS(AE_BAD_PARAMETER);
162 }
163
164 /* Support for multiple acquires by the owning thread */
165
166 if (obj_desc->mutex.thread_id == thread_id) {
167 /*
168 * The mutex is already owned by this thread, just increment the
169 * acquisition depth
170 */
171 obj_desc->mutex.acquisition_depth++;
172 return_ACPI_STATUS(AE_OK);
173 }
174
175 /* Acquire the mutex, wait if necessary. Special case for Global Lock */
176
177 if (obj_desc == acpi_gbl_global_lock_mutex) {
178 status = acpi_ev_acquire_global_lock(timeout);
179 } else {
180 status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex,
181 timeout);
182 }
183
184 if (ACPI_FAILURE(status)) {
185
186 /* Includes failure from a timeout on time_desc */
187
188 return_ACPI_STATUS(status);
189 }
190
191 /* Acquired the mutex: update mutex object */
192
193 obj_desc->mutex.thread_id = thread_id;
194 obj_desc->mutex.acquisition_depth = 1;
195 obj_desc->mutex.original_sync_level = 0;
196 obj_desc->mutex.owner_thread = NULL; /* Used only for AML Acquire() */
197
198 return_ACPI_STATUS(AE_OK);
199 }
200
201 /*******************************************************************************
202 *
203 * FUNCTION: acpi_ex_acquire_mutex
204 *
205 * PARAMETERS: time_desc - Timeout integer
206 * obj_desc - Mutex object
207 * walk_state - Current method execution state
208 *
209 * RETURN: Status
210 *
211 * DESCRIPTION: Acquire an AML mutex
212 *
213 ******************************************************************************/
214
215 acpi_status
acpi_ex_acquire_mutex(union acpi_operand_object * time_desc,union acpi_operand_object * obj_desc,struct acpi_walk_state * walk_state)216 acpi_ex_acquire_mutex(union acpi_operand_object *time_desc,
217 union acpi_operand_object *obj_desc,
218 struct acpi_walk_state *walk_state)
219 {
220 acpi_status status;
221
222 ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex, obj_desc);
223
224 if (!obj_desc) {
225 return_ACPI_STATUS(AE_BAD_PARAMETER);
226 }
227
228 /* Must have a valid thread ID */
229
230 if (!walk_state->thread) {
231 ACPI_ERROR((AE_INFO,
232 "Cannot acquire Mutex [%4.4s], null thread info",
233 acpi_ut_get_node_name(obj_desc->mutex.node)));
234 return_ACPI_STATUS(AE_AML_INTERNAL);
235 }
236
237 /*
238 * Current sync level must be less than or equal to the sync level of the
239 * mutex. This mechanism provides some deadlock prevention
240 */
241 if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) {
242 ACPI_ERROR((AE_INFO,
243 "Cannot acquire Mutex [%4.4s], current SyncLevel is too large (%d)",
244 acpi_ut_get_node_name(obj_desc->mutex.node),
245 walk_state->thread->current_sync_level));
246 return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
247 }
248
249 status = acpi_ex_acquire_mutex_object((u16) time_desc->integer.value,
250 obj_desc,
251 walk_state->thread->thread_id);
252 if (ACPI_SUCCESS(status) && obj_desc->mutex.acquisition_depth == 1) {
253
254 /* Save Thread object, original/current sync levels */
255
256 obj_desc->mutex.owner_thread = walk_state->thread;
257 obj_desc->mutex.original_sync_level =
258 walk_state->thread->current_sync_level;
259 walk_state->thread->current_sync_level =
260 obj_desc->mutex.sync_level;
261
262 /* Link the mutex to the current thread for force-unlock at method exit */
263
264 acpi_ex_link_mutex(obj_desc, walk_state->thread);
265 }
266
267 return_ACPI_STATUS(status);
268 }
269
270 /*******************************************************************************
271 *
272 * FUNCTION: acpi_ex_release_mutex_object
273 *
274 * PARAMETERS: obj_desc - The object descriptor for this op
275 *
276 * RETURN: Status
277 *
278 * DESCRIPTION: Release a previously acquired Mutex, low level interface.
279 * Provides a common path that supports multiple releases (after
280 * previous multiple acquires) by the same thread.
281 *
282 * MUTEX: Interpreter must be locked
283 *
284 * NOTE: This interface is called from three places:
285 * 1) From acpi_ex_release_mutex, via an AML Acquire() operator
286 * 2) From acpi_ex_release_global_lock when an AML Field access requires the
287 * global lock
288 * 3) From the external interface, acpi_release_global_lock
289 *
290 ******************************************************************************/
291
acpi_ex_release_mutex_object(union acpi_operand_object * obj_desc)292 acpi_status acpi_ex_release_mutex_object(union acpi_operand_object *obj_desc)
293 {
294 acpi_status status = AE_OK;
295
296 ACPI_FUNCTION_TRACE(ex_release_mutex_object);
297
298 if (obj_desc->mutex.acquisition_depth == 0) {
299 return (AE_NOT_ACQUIRED);
300 }
301
302 /* Match multiple Acquires with multiple Releases */
303
304 obj_desc->mutex.acquisition_depth--;
305 if (obj_desc->mutex.acquisition_depth != 0) {
306
307 /* Just decrement the depth and return */
308
309 return_ACPI_STATUS(AE_OK);
310 }
311
312 if (obj_desc->mutex.owner_thread) {
313
314 /* Unlink the mutex from the owner's list */
315
316 acpi_ex_unlink_mutex(obj_desc);
317 obj_desc->mutex.owner_thread = NULL;
318 }
319
320 /* Release the mutex, special case for Global Lock */
321
322 if (obj_desc == acpi_gbl_global_lock_mutex) {
323 status = acpi_ev_release_global_lock();
324 } else {
325 acpi_os_release_mutex(obj_desc->mutex.os_mutex);
326 }
327
328 /* Clear mutex info */
329
330 obj_desc->mutex.thread_id = NULL;
331 return_ACPI_STATUS(status);
332 }
333
334 /*******************************************************************************
335 *
336 * FUNCTION: acpi_ex_release_mutex
337 *
338 * PARAMETERS: obj_desc - The object descriptor for this op
339 * walk_state - Current method execution state
340 *
341 * RETURN: Status
342 *
343 * DESCRIPTION: Release a previously acquired Mutex.
344 *
345 ******************************************************************************/
346
347 acpi_status
acpi_ex_release_mutex(union acpi_operand_object * obj_desc,struct acpi_walk_state * walk_state)348 acpi_ex_release_mutex(union acpi_operand_object *obj_desc,
349 struct acpi_walk_state *walk_state)
350 {
351 acpi_status status = AE_OK;
352
353 ACPI_FUNCTION_TRACE(ex_release_mutex);
354
355 if (!obj_desc) {
356 return_ACPI_STATUS(AE_BAD_PARAMETER);
357 }
358
359 /* The mutex must have been previously acquired in order to release it */
360
361 if (!obj_desc->mutex.owner_thread) {
362 ACPI_ERROR((AE_INFO,
363 "Cannot release Mutex [%4.4s], not acquired",
364 acpi_ut_get_node_name(obj_desc->mutex.node)));
365 return_ACPI_STATUS(AE_AML_MUTEX_NOT_ACQUIRED);
366 }
367
368 /*
369 * The Mutex is owned, but this thread must be the owner.
370 * Special case for Global Lock, any thread can release
371 */
372 if ((obj_desc->mutex.owner_thread->thread_id !=
373 walk_state->thread->thread_id)
374 && (obj_desc != acpi_gbl_global_lock_mutex)) {
375 ACPI_ERROR((AE_INFO,
376 "Thread %lX cannot release Mutex [%4.4s] acquired by thread %lX",
377 (unsigned long)walk_state->thread->thread_id,
378 acpi_ut_get_node_name(obj_desc->mutex.node),
379 (unsigned long)obj_desc->mutex.owner_thread->
380 thread_id));
381 return_ACPI_STATUS(AE_AML_NOT_OWNER);
382 }
383
384 /* Must have a valid thread ID */
385
386 if (!walk_state->thread) {
387 ACPI_ERROR((AE_INFO,
388 "Cannot release Mutex [%4.4s], null thread info",
389 acpi_ut_get_node_name(obj_desc->mutex.node)));
390 return_ACPI_STATUS(AE_AML_INTERNAL);
391 }
392
393 /*
394 * The sync level of the mutex must be less than or equal to the current
395 * sync level
396 */
397 if (obj_desc->mutex.sync_level > walk_state->thread->current_sync_level) {
398 ACPI_ERROR((AE_INFO,
399 "Cannot release Mutex [%4.4s], SyncLevel mismatch: mutex %d current %d",
400 acpi_ut_get_node_name(obj_desc->mutex.node),
401 obj_desc->mutex.sync_level,
402 walk_state->thread->current_sync_level));
403 return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
404 }
405
406 status = acpi_ex_release_mutex_object(obj_desc);
407
408 if (obj_desc->mutex.acquisition_depth == 0) {
409
410 /* Restore the original sync_level */
411
412 walk_state->thread->current_sync_level =
413 obj_desc->mutex.original_sync_level;
414 }
415 return_ACPI_STATUS(status);
416 }
417
418 /*******************************************************************************
419 *
420 * FUNCTION: acpi_ex_release_all_mutexes
421 *
422 * PARAMETERS: Thread - Current executing thread object
423 *
424 * RETURN: Status
425 *
426 * DESCRIPTION: Release all mutexes held by this thread
427 *
428 * NOTE: This function is called as the thread is exiting the interpreter.
429 * Mutexes are not released when an individual control method is exited, but
430 * only when the parent thread actually exits the interpreter. This allows one
431 * method to acquire a mutex, and a different method to release it, as long as
432 * this is performed underneath a single parent control method.
433 *
434 ******************************************************************************/
435
acpi_ex_release_all_mutexes(struct acpi_thread_state * thread)436 void acpi_ex_release_all_mutexes(struct acpi_thread_state *thread)
437 {
438 union acpi_operand_object *next = thread->acquired_mutex_list;
439 union acpi_operand_object *obj_desc;
440
441 ACPI_FUNCTION_ENTRY();
442
443 /* Traverse the list of owned mutexes, releasing each one */
444
445 while (next) {
446 obj_desc = next;
447 next = obj_desc->mutex.next;
448
449 obj_desc->mutex.prev = NULL;
450 obj_desc->mutex.next = NULL;
451 obj_desc->mutex.acquisition_depth = 0;
452
453 /* Release the mutex, special case for Global Lock */
454
455 if (obj_desc == acpi_gbl_global_lock_mutex) {
456
457 /* Ignore errors */
458
459 (void)acpi_ev_release_global_lock();
460 } else {
461 acpi_os_release_mutex(obj_desc->mutex.os_mutex);
462 }
463
464 /* Mark mutex unowned */
465
466 obj_desc->mutex.owner_thread = NULL;
467 obj_desc->mutex.thread_id = NULL;
468
469 /* Update Thread sync_level (Last mutex is the important one) */
470
471 thread->current_sync_level =
472 obj_desc->mutex.original_sync_level;
473 }
474 }
475