1 /******************************************************************************
2 *
3 * Module Name: exmutex - ASL Mutex Acquire/Release functions
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2013, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44 #define __EXMUTEX_C__
45
46 #include "acpi.h"
47 #include "accommon.h"
48 #include "acinterp.h"
49 #include "acevents.h"
50
51 #define _COMPONENT ACPI_EXECUTER
52 ACPI_MODULE_NAME ("exmutex")
53
54 /* Local prototypes */
55
56 static void
57 AcpiExLinkMutex (
58 ACPI_OPERAND_OBJECT *ObjDesc,
59 ACPI_THREAD_STATE *Thread);
60
61
62 /*******************************************************************************
63 *
64 * FUNCTION: AcpiExUnlinkMutex
65 *
66 * PARAMETERS: ObjDesc - The mutex to be unlinked
67 *
68 * RETURN: None
69 *
70 * DESCRIPTION: Remove a mutex from the "AcquiredMutex" list
71 *
72 ******************************************************************************/
73
74 void
75 AcpiExUnlinkMutex (
76 ACPI_OPERAND_OBJECT *ObjDesc)
77 {
78 ACPI_THREAD_STATE *Thread = ObjDesc->Mutex.OwnerThread;
79
80
81 if (!Thread)
82 {
83 return;
84 }
85
86 /* Doubly linked list */
87
88 if (ObjDesc->Mutex.Next)
89 {
90 (ObjDesc->Mutex.Next)->Mutex.Prev = ObjDesc->Mutex.Prev;
91 }
92
93 if (ObjDesc->Mutex.Prev)
94 {
95 (ObjDesc->Mutex.Prev)->Mutex.Next = ObjDesc->Mutex.Next;
96
97 /*
98 * Migrate the previous sync level associated with this mutex to
99 * the previous mutex on the list so that it may be preserved.
100 * This handles the case where several mutexes have been acquired
101 * at the same level, but are not released in opposite order.
102 */
103 (ObjDesc->Mutex.Prev)->Mutex.OriginalSyncLevel =
104 ObjDesc->Mutex.OriginalSyncLevel;
105 }
106 else
107 {
108 Thread->AcquiredMutexList = ObjDesc->Mutex.Next;
109 }
110 }
111
112
113 /*******************************************************************************
114 *
115 * FUNCTION: AcpiExLinkMutex
116 *
117 * PARAMETERS: ObjDesc - The mutex to be linked
118 * Thread - Current executing thread object
119 *
120 * RETURN: None
121 *
122 * DESCRIPTION: Add a mutex to the "AcquiredMutex" list for this walk
123 *
124 ******************************************************************************/
125
126 static void
127 AcpiExLinkMutex (
128 ACPI_OPERAND_OBJECT *ObjDesc,
129 ACPI_THREAD_STATE *Thread)
130 {
131 ACPI_OPERAND_OBJECT *ListHead;
132
133
134 ListHead = Thread->AcquiredMutexList;
135
136 /* This object will be the first object in the list */
137
138 ObjDesc->Mutex.Prev = NULL;
139 ObjDesc->Mutex.Next = ListHead;
140
141 /* Update old first object to point back to this object */
142
143 if (ListHead)
144 {
145 ListHead->Mutex.Prev = ObjDesc;
146 }
147
148 /* Update list head */
149
150 Thread->AcquiredMutexList = ObjDesc;
151 }
152
153
154 /*******************************************************************************
155 *
156 * FUNCTION: AcpiExAcquireMutexObject
157 *
158 * PARAMETERS: Timeout - Timeout in milliseconds
159 * ObjDesc - Mutex object
160 * ThreadId - Current thread state
161 *
162 * RETURN: Status
163 *
164 * DESCRIPTION: Acquire an AML mutex, low-level interface. Provides a common
165 * path that supports multiple acquires by the same thread.
166 *
167 * MUTEX: Interpreter must be locked
168 *
169 * NOTE: This interface is called from three places:
170 * 1) From AcpiExAcquireMutex, via an AML Acquire() operator
171 * 2) From AcpiExAcquireGlobalLock when an AML Field access requires the
172 * global lock
173 * 3) From the external interface, AcpiAcquireGlobalLock
174 *
175 ******************************************************************************/
176
177 ACPI_STATUS
178 AcpiExAcquireMutexObject (
179 UINT16 Timeout,
180 ACPI_OPERAND_OBJECT *ObjDesc,
181 ACPI_THREAD_ID ThreadId)
182 {
183 ACPI_STATUS Status;
184
185
186 ACPI_FUNCTION_TRACE_PTR (ExAcquireMutexObject, ObjDesc);
187
188
189 if (!ObjDesc)
190 {
191 return_ACPI_STATUS (AE_BAD_PARAMETER);
192 }
193
194 /* Support for multiple acquires by the owning thread */
195
196 if (ObjDesc->Mutex.ThreadId == ThreadId)
197 {
198 /*
199 * The mutex is already owned by this thread, just increment the
200 * acquisition depth
201 */
202 ObjDesc->Mutex.AcquisitionDepth++;
203 return_ACPI_STATUS (AE_OK);
204 }
205
206 /* Acquire the mutex, wait if necessary. Special case for Global Lock */
207
208 if (ObjDesc == AcpiGbl_GlobalLockMutex)
209 {
210 Status = AcpiEvAcquireGlobalLock (Timeout);
211 }
212 else
213 {
214 Status = AcpiExSystemWaitMutex (ObjDesc->Mutex.OsMutex,
215 Timeout);
216 }
217
218 if (ACPI_FAILURE (Status))
219 {
220 /* Includes failure from a timeout on TimeDesc */
221
222 return_ACPI_STATUS (Status);
223 }
224
225 /* Acquired the mutex: update mutex object */
226
227 ObjDesc->Mutex.ThreadId = ThreadId;
228 ObjDesc->Mutex.AcquisitionDepth = 1;
229 ObjDesc->Mutex.OriginalSyncLevel = 0;
230 ObjDesc->Mutex.OwnerThread = NULL; /* Used only for AML Acquire() */
231
232 return_ACPI_STATUS (AE_OK);
233 }
234
235
236 /*******************************************************************************
237 *
238 * FUNCTION: AcpiExAcquireMutex
239 *
240 * PARAMETERS: TimeDesc - Timeout integer
241 * ObjDesc - Mutex object
242 * WalkState - Current method execution state
243 *
244 * RETURN: Status
245 *
246 * DESCRIPTION: Acquire an AML mutex
247 *
248 ******************************************************************************/
249
250 ACPI_STATUS
251 AcpiExAcquireMutex (
252 ACPI_OPERAND_OBJECT *TimeDesc,
253 ACPI_OPERAND_OBJECT *ObjDesc,
254 ACPI_WALK_STATE *WalkState)
255 {
256 ACPI_STATUS Status;
257
258
259 ACPI_FUNCTION_TRACE_PTR (ExAcquireMutex, ObjDesc);
260
261
262 if (!ObjDesc)
263 {
264 return_ACPI_STATUS (AE_BAD_PARAMETER);
265 }
266
267 /* Must have a valid thread state struct */
268
269 if (!WalkState->Thread)
270 {
271 ACPI_ERROR ((AE_INFO,
272 "Cannot acquire Mutex [%4.4s], null thread info",
273 AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
274 return_ACPI_STATUS (AE_AML_INTERNAL);
275 }
276
277 /*
278 * Current sync level must be less than or equal to the sync level of the
279 * mutex. This mechanism provides some deadlock prevention
280 */
281 if (WalkState->Thread->CurrentSyncLevel > ObjDesc->Mutex.SyncLevel)
282 {
283 ACPI_ERROR ((AE_INFO,
284 "Cannot acquire Mutex [%4.4s], current SyncLevel is too large (%u)",
285 AcpiUtGetNodeName (ObjDesc->Mutex.Node),
286 WalkState->Thread->CurrentSyncLevel));
287 return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
288 }
289
290 Status = AcpiExAcquireMutexObject ((UINT16) TimeDesc->Integer.Value,
291 ObjDesc, WalkState->Thread->ThreadId);
292 if (ACPI_SUCCESS (Status) && ObjDesc->Mutex.AcquisitionDepth == 1)
293 {
294 /* Save Thread object, original/current sync levels */
295
296 ObjDesc->Mutex.OwnerThread = WalkState->Thread;
297 ObjDesc->Mutex.OriginalSyncLevel = WalkState->Thread->CurrentSyncLevel;
298 WalkState->Thread->CurrentSyncLevel = ObjDesc->Mutex.SyncLevel;
299
300 /* Link the mutex to the current thread for force-unlock at method exit */
301
302 AcpiExLinkMutex (ObjDesc, WalkState->Thread);
303 }
304
305 return_ACPI_STATUS (Status);
306 }
307
308
309 /*******************************************************************************
310 *
311 * FUNCTION: AcpiExReleaseMutexObject
312 *
313 * PARAMETERS: ObjDesc - The object descriptor for this op
314 *
315 * RETURN: Status
316 *
317 * DESCRIPTION: Release a previously acquired Mutex, low level interface.
318 * Provides a common path that supports multiple releases (after
319 * previous multiple acquires) by the same thread.
320 *
321 * MUTEX: Interpreter must be locked
322 *
323 * NOTE: This interface is called from three places:
324 * 1) From AcpiExReleaseMutex, via an AML Acquire() operator
325 * 2) From AcpiExReleaseGlobalLock when an AML Field access requires the
326 * global lock
327 * 3) From the external interface, AcpiReleaseGlobalLock
328 *
329 ******************************************************************************/
330
331 ACPI_STATUS
332 AcpiExReleaseMutexObject (
333 ACPI_OPERAND_OBJECT *ObjDesc)
334 {
335 ACPI_STATUS Status = AE_OK;
336
337
338 ACPI_FUNCTION_TRACE (ExReleaseMutexObject);
339
340
341 if (ObjDesc->Mutex.AcquisitionDepth == 0)
342 {
343 return_ACPI_STATUS (AE_NOT_ACQUIRED);
344 }
345
346 /* Match multiple Acquires with multiple Releases */
347
348 ObjDesc->Mutex.AcquisitionDepth--;
349 if (ObjDesc->Mutex.AcquisitionDepth != 0)
350 {
351 /* Just decrement the depth and return */
352
353 return_ACPI_STATUS (AE_OK);
354 }
355
356 if (ObjDesc->Mutex.OwnerThread)
357 {
358 /* Unlink the mutex from the owner's list */
359
360 AcpiExUnlinkMutex (ObjDesc);
361 ObjDesc->Mutex.OwnerThread = NULL;
362 }
363
364 /* Release the mutex, special case for Global Lock */
365
366 if (ObjDesc == AcpiGbl_GlobalLockMutex)
367 {
368 Status = AcpiEvReleaseGlobalLock ();
369 }
370 else
371 {
372 AcpiOsReleaseMutex (ObjDesc->Mutex.OsMutex);
373 }
374
375 /* Clear mutex info */
376
377 ObjDesc->Mutex.ThreadId = 0;
378 return_ACPI_STATUS (Status);
379 }
380
381
382 /*******************************************************************************
383 *
384 * FUNCTION: AcpiExReleaseMutex
385 *
386 * PARAMETERS: ObjDesc - The object descriptor for this op
387 * WalkState - Current method execution state
388 *
389 * RETURN: Status
390 *
391 * DESCRIPTION: Release a previously acquired Mutex.
392 *
393 ******************************************************************************/
394
395 ACPI_STATUS
396 AcpiExReleaseMutex (
397 ACPI_OPERAND_OBJECT *ObjDesc,
398 ACPI_WALK_STATE *WalkState)
399 {
400 ACPI_STATUS Status = AE_OK;
401 UINT8 PreviousSyncLevel;
402 ACPI_THREAD_STATE *OwnerThread;
403
404
405 ACPI_FUNCTION_TRACE (ExReleaseMutex);
406
407
408 if (!ObjDesc)
409 {
410 return_ACPI_STATUS (AE_BAD_PARAMETER);
411 }
412
413 OwnerThread = ObjDesc->Mutex.OwnerThread;
414
415 /* The mutex must have been previously acquired in order to release it */
416
417 if (!OwnerThread)
418 {
419 ACPI_ERROR ((AE_INFO,
420 "Cannot release Mutex [%4.4s], not acquired",
421 AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
422 return_ACPI_STATUS (AE_AML_MUTEX_NOT_ACQUIRED);
423 }
424
425 /* Must have a valid thread ID */
426
427 if (!WalkState->Thread)
428 {
429 ACPI_ERROR ((AE_INFO,
430 "Cannot release Mutex [%4.4s], null thread info",
431 AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
432 return_ACPI_STATUS (AE_AML_INTERNAL);
433 }
434
435 /*
436 * The Mutex is owned, but this thread must be the owner.
437 * Special case for Global Lock, any thread can release
438 */
439 if ((OwnerThread->ThreadId != WalkState->Thread->ThreadId) &&
440 (ObjDesc != AcpiGbl_GlobalLockMutex))
441 {
442 ACPI_ERROR ((AE_INFO,
443 "Thread %u cannot release Mutex [%4.4s] acquired by thread %u",
444 (UINT32) WalkState->Thread->ThreadId,
445 AcpiUtGetNodeName (ObjDesc->Mutex.Node),
446 (UINT32) OwnerThread->ThreadId));
447 return_ACPI_STATUS (AE_AML_NOT_OWNER);
448 }
449
450 /*
451 * The sync level of the mutex must be equal to the current sync level. In
452 * other words, the current level means that at least one mutex at that
453 * level is currently being held. Attempting to release a mutex of a
454 * different level can only mean that the mutex ordering rule is being
455 * violated. This behavior is clarified in ACPI 4.0 specification.
456 */
457 if (ObjDesc->Mutex.SyncLevel != OwnerThread->CurrentSyncLevel)
458 {
459 ACPI_ERROR ((AE_INFO,
460 "Cannot release Mutex [%4.4s], SyncLevel mismatch: mutex %u current %u",
461 AcpiUtGetNodeName (ObjDesc->Mutex.Node),
462 ObjDesc->Mutex.SyncLevel, WalkState->Thread->CurrentSyncLevel));
463 return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
464 }
465
466 /*
467 * Get the previous SyncLevel from the head of the acquired mutex list.
468 * This handles the case where several mutexes at the same level have been
469 * acquired, but are not released in reverse order.
470 */
471 PreviousSyncLevel =
472 OwnerThread->AcquiredMutexList->Mutex.OriginalSyncLevel;
473
474 Status = AcpiExReleaseMutexObject (ObjDesc);
475 if (ACPI_FAILURE (Status))
476 {
477 return_ACPI_STATUS (Status);
478 }
479
480 if (ObjDesc->Mutex.AcquisitionDepth == 0)
481 {
482 /* Restore the previous SyncLevel */
483
484 OwnerThread->CurrentSyncLevel = PreviousSyncLevel;
485 }
486
487 return_ACPI_STATUS (Status);
488 }
489
490
491 /*******************************************************************************
492 *
493 * FUNCTION: AcpiExReleaseAllMutexes
494 *
495 * PARAMETERS: Thread - Current executing thread object
496 *
497 * RETURN: Status
498 *
499 * DESCRIPTION: Release all mutexes held by this thread
500 *
501 * NOTE: This function is called as the thread is exiting the interpreter.
502 * Mutexes are not released when an individual control method is exited, but
503 * only when the parent thread actually exits the interpreter. This allows one
504 * method to acquire a mutex, and a different method to release it, as long as
505 * this is performed underneath a single parent control method.
506 *
507 ******************************************************************************/
508
509 void
510 AcpiExReleaseAllMutexes (
511 ACPI_THREAD_STATE *Thread)
512 {
513 ACPI_OPERAND_OBJECT *Next = Thread->AcquiredMutexList;
514 ACPI_OPERAND_OBJECT *ObjDesc;
515
516
517 ACPI_FUNCTION_NAME (ExReleaseAllMutexes);
518
519
520 /* Traverse the list of owned mutexes, releasing each one */
521
522 while (Next)
523 {
524 ObjDesc = Next;
525 Next = ObjDesc->Mutex.Next;
526
527 ObjDesc->Mutex.Prev = NULL;
528 ObjDesc->Mutex.Next = NULL;
529 ObjDesc->Mutex.AcquisitionDepth = 0;
530
531 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
532 "Force-releasing held mutex: %p\n", ObjDesc));
533
534 /* Release the mutex, special case for Global Lock */
535
536 if (ObjDesc == AcpiGbl_GlobalLockMutex)
537 {
538 /* Ignore errors */
539
540 (void) AcpiEvReleaseGlobalLock ();
541 }
542 else
543 {
544 AcpiOsReleaseMutex (ObjDesc->Mutex.OsMutex);
545 }
546
547 /* Mark mutex unowned */
548
549 ObjDesc->Mutex.OwnerThread = NULL;
550 ObjDesc->Mutex.ThreadId = 0;
551
552 /* Update Thread SyncLevel (Last mutex is the important one) */
553
554 Thread->CurrentSyncLevel = ObjDesc->Mutex.OriginalSyncLevel;
555 }
556 }