1 /******************************************************************************
2 *
3 * Module Name: exmutex - ASL Mutex Acquire/Release functions
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2014, 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 #include "acpi.h"
45 #include "accommon.h"
46 #include "acinterp.h"
47 #include "acevents.h"
48
49 #define _COMPONENT ACPI_EXECUTER
50 ACPI_MODULE_NAME ("exmutex")
51
52 /* Local prototypes */
53
54 static void
55 AcpiExLinkMutex (
56 ACPI_OPERAND_OBJECT *ObjDesc,
57 ACPI_THREAD_STATE *Thread);
58
59
60 /*******************************************************************************
61 *
62 * FUNCTION: AcpiExUnlinkMutex
63 *
64 * PARAMETERS: ObjDesc - The mutex to be unlinked
65 *
66 * RETURN: None
67 *
68 * DESCRIPTION: Remove a mutex from the "AcquiredMutex" list
69 *
70 ******************************************************************************/
71
72 void
AcpiExUnlinkMutex(ACPI_OPERAND_OBJECT * ObjDesc)73 AcpiExUnlinkMutex (
74 ACPI_OPERAND_OBJECT *ObjDesc)
75 {
76 ACPI_THREAD_STATE *Thread = ObjDesc->Mutex.OwnerThread;
77
78
79 if (!Thread)
80 {
81 return;
82 }
83
84 /* Doubly linked list */
85
86 if (ObjDesc->Mutex.Next)
87 {
88 (ObjDesc->Mutex.Next)->Mutex.Prev = ObjDesc->Mutex.Prev;
89 }
90
91 if (ObjDesc->Mutex.Prev)
92 {
93 (ObjDesc->Mutex.Prev)->Mutex.Next = ObjDesc->Mutex.Next;
94
95 /*
96 * Migrate the previous sync level associated with this mutex to
97 * the previous mutex on the list so that it may be preserved.
98 * This handles the case where several mutexes have been acquired
99 * at the same level, but are not released in opposite order.
100 */
101 (ObjDesc->Mutex.Prev)->Mutex.OriginalSyncLevel =
102 ObjDesc->Mutex.OriginalSyncLevel;
103 }
104 else
105 {
106 Thread->AcquiredMutexList = ObjDesc->Mutex.Next;
107 }
108 }
109
110
111 /*******************************************************************************
112 *
113 * FUNCTION: AcpiExLinkMutex
114 *
115 * PARAMETERS: ObjDesc - The mutex to be linked
116 * Thread - Current executing thread object
117 *
118 * RETURN: None
119 *
120 * DESCRIPTION: Add a mutex to the "AcquiredMutex" list for this walk
121 *
122 ******************************************************************************/
123
124 static void
AcpiExLinkMutex(ACPI_OPERAND_OBJECT * ObjDesc,ACPI_THREAD_STATE * Thread)125 AcpiExLinkMutex (
126 ACPI_OPERAND_OBJECT *ObjDesc,
127 ACPI_THREAD_STATE *Thread)
128 {
129 ACPI_OPERAND_OBJECT *ListHead;
130
131
132 ListHead = Thread->AcquiredMutexList;
133
134 /* This object will be the first object in the list */
135
136 ObjDesc->Mutex.Prev = NULL;
137 ObjDesc->Mutex.Next = ListHead;
138
139 /* Update old first object to point back to this object */
140
141 if (ListHead)
142 {
143 ListHead->Mutex.Prev = ObjDesc;
144 }
145
146 /* Update list head */
147
148 Thread->AcquiredMutexList = ObjDesc;
149 }
150
151
152 /*******************************************************************************
153 *
154 * FUNCTION: AcpiExAcquireMutexObject
155 *
156 * PARAMETERS: Timeout - Timeout in milliseconds
157 * ObjDesc - Mutex object
158 * ThreadId - Current thread state
159 *
160 * RETURN: Status
161 *
162 * DESCRIPTION: Acquire an AML mutex, low-level interface. Provides a common
163 * path that supports multiple acquires by the same thread.
164 *
165 * MUTEX: Interpreter must be locked
166 *
167 * NOTE: This interface is called from three places:
168 * 1) From AcpiExAcquireMutex, via an AML Acquire() operator
169 * 2) From AcpiExAcquireGlobalLock when an AML Field access requires the
170 * global lock
171 * 3) From the external interface, AcpiAcquireGlobalLock
172 *
173 ******************************************************************************/
174
175 ACPI_STATUS
AcpiExAcquireMutexObject(UINT16 Timeout,ACPI_OPERAND_OBJECT * ObjDesc,ACPI_THREAD_ID ThreadId)176 AcpiExAcquireMutexObject (
177 UINT16 Timeout,
178 ACPI_OPERAND_OBJECT *ObjDesc,
179 ACPI_THREAD_ID ThreadId)
180 {
181 ACPI_STATUS Status;
182
183
184 ACPI_FUNCTION_TRACE_PTR (ExAcquireMutexObject, ObjDesc);
185
186
187 if (!ObjDesc)
188 {
189 return_ACPI_STATUS (AE_BAD_PARAMETER);
190 }
191
192 /* Support for multiple acquires by the owning thread */
193
194 if (ObjDesc->Mutex.ThreadId == ThreadId)
195 {
196 /*
197 * The mutex is already owned by this thread, just increment the
198 * acquisition depth
199 */
200 ObjDesc->Mutex.AcquisitionDepth++;
201 return_ACPI_STATUS (AE_OK);
202 }
203
204 /* Acquire the mutex, wait if necessary. Special case for Global Lock */
205
206 if (ObjDesc == AcpiGbl_GlobalLockMutex)
207 {
208 Status = AcpiEvAcquireGlobalLock (Timeout);
209 }
210 else
211 {
212 Status = AcpiExSystemWaitMutex (ObjDesc->Mutex.OsMutex,
213 Timeout);
214 }
215
216 if (ACPI_FAILURE (Status))
217 {
218 /* Includes failure from a timeout on TimeDesc */
219
220 return_ACPI_STATUS (Status);
221 }
222
223 /* Acquired the mutex: update mutex object */
224
225 ObjDesc->Mutex.ThreadId = ThreadId;
226 ObjDesc->Mutex.AcquisitionDepth = 1;
227 ObjDesc->Mutex.OriginalSyncLevel = 0;
228 ObjDesc->Mutex.OwnerThread = NULL; /* Used only for AML Acquire() */
229
230 return_ACPI_STATUS (AE_OK);
231 }
232
233
234 /*******************************************************************************
235 *
236 * FUNCTION: AcpiExAcquireMutex
237 *
238 * PARAMETERS: TimeDesc - Timeout integer
239 * ObjDesc - Mutex object
240 * WalkState - Current method execution state
241 *
242 * RETURN: Status
243 *
244 * DESCRIPTION: Acquire an AML mutex
245 *
246 ******************************************************************************/
247
248 ACPI_STATUS
AcpiExAcquireMutex(ACPI_OPERAND_OBJECT * TimeDesc,ACPI_OPERAND_OBJECT * ObjDesc,ACPI_WALK_STATE * WalkState)249 AcpiExAcquireMutex (
250 ACPI_OPERAND_OBJECT *TimeDesc,
251 ACPI_OPERAND_OBJECT *ObjDesc,
252 ACPI_WALK_STATE *WalkState)
253 {
254 ACPI_STATUS Status;
255
256
257 ACPI_FUNCTION_TRACE_PTR (ExAcquireMutex, ObjDesc);
258
259
260 if (!ObjDesc)
261 {
262 return_ACPI_STATUS (AE_BAD_PARAMETER);
263 }
264
265 /* Must have a valid thread state struct */
266
267 if (!WalkState->Thread)
268 {
269 ACPI_ERROR ((AE_INFO,
270 "Cannot acquire Mutex [%4.4s], null thread info",
271 AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
272 return_ACPI_STATUS (AE_AML_INTERNAL);
273 }
274
275 /*
276 * Current sync level must be less than or equal to the sync level of the
277 * mutex. This mechanism provides some deadlock prevention
278 */
279 if (WalkState->Thread->CurrentSyncLevel > ObjDesc->Mutex.SyncLevel)
280 {
281 ACPI_ERROR ((AE_INFO,
282 "Cannot acquire Mutex [%4.4s], current SyncLevel is too large (%u)",
283 AcpiUtGetNodeName (ObjDesc->Mutex.Node),
284 WalkState->Thread->CurrentSyncLevel));
285 return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
286 }
287
288 Status = AcpiExAcquireMutexObject ((UINT16) TimeDesc->Integer.Value,
289 ObjDesc, WalkState->Thread->ThreadId);
290 if (ACPI_SUCCESS (Status) && ObjDesc->Mutex.AcquisitionDepth == 1)
291 {
292 /* Save Thread object, original/current sync levels */
293
294 ObjDesc->Mutex.OwnerThread = WalkState->Thread;
295 ObjDesc->Mutex.OriginalSyncLevel = WalkState->Thread->CurrentSyncLevel;
296 WalkState->Thread->CurrentSyncLevel = ObjDesc->Mutex.SyncLevel;
297
298 /* Link the mutex to the current thread for force-unlock at method exit */
299
300 AcpiExLinkMutex (ObjDesc, WalkState->Thread);
301 }
302
303 return_ACPI_STATUS (Status);
304 }
305
306
307 /*******************************************************************************
308 *
309 * FUNCTION: AcpiExReleaseMutexObject
310 *
311 * PARAMETERS: ObjDesc - The object descriptor for this op
312 *
313 * RETURN: Status
314 *
315 * DESCRIPTION: Release a previously acquired Mutex, low level interface.
316 * Provides a common path that supports multiple releases (after
317 * previous multiple acquires) by the same thread.
318 *
319 * MUTEX: Interpreter must be locked
320 *
321 * NOTE: This interface is called from three places:
322 * 1) From AcpiExReleaseMutex, via an AML Acquire() operator
323 * 2) From AcpiExReleaseGlobalLock when an AML Field access requires the
324 * global lock
325 * 3) From the external interface, AcpiReleaseGlobalLock
326 *
327 ******************************************************************************/
328
329 ACPI_STATUS
AcpiExReleaseMutexObject(ACPI_OPERAND_OBJECT * ObjDesc)330 AcpiExReleaseMutexObject (
331 ACPI_OPERAND_OBJECT *ObjDesc)
332 {
333 ACPI_STATUS Status = AE_OK;
334
335
336 ACPI_FUNCTION_TRACE (ExReleaseMutexObject);
337
338
339 if (ObjDesc->Mutex.AcquisitionDepth == 0)
340 {
341 return_ACPI_STATUS (AE_NOT_ACQUIRED);
342 }
343
344 /* Match multiple Acquires with multiple Releases */
345
346 ObjDesc->Mutex.AcquisitionDepth--;
347 if (ObjDesc->Mutex.AcquisitionDepth != 0)
348 {
349 /* Just decrement the depth and return */
350
351 return_ACPI_STATUS (AE_OK);
352 }
353
354 if (ObjDesc->Mutex.OwnerThread)
355 {
356 /* Unlink the mutex from the owner's list */
357
358 AcpiExUnlinkMutex (ObjDesc);
359 ObjDesc->Mutex.OwnerThread = NULL;
360 }
361
362 /* Release the mutex, special case for Global Lock */
363
364 if (ObjDesc == AcpiGbl_GlobalLockMutex)
365 {
366 Status = AcpiEvReleaseGlobalLock ();
367 }
368 else
369 {
370 AcpiOsReleaseMutex (ObjDesc->Mutex.OsMutex);
371 }
372
373 /* Clear mutex info */
374
375 ObjDesc->Mutex.ThreadId = 0;
376 return_ACPI_STATUS (Status);
377 }
378
379
380 /*******************************************************************************
381 *
382 * FUNCTION: AcpiExReleaseMutex
383 *
384 * PARAMETERS: ObjDesc - The object descriptor for this op
385 * WalkState - Current method execution state
386 *
387 * RETURN: Status
388 *
389 * DESCRIPTION: Release a previously acquired Mutex.
390 *
391 ******************************************************************************/
392
393 ACPI_STATUS
AcpiExReleaseMutex(ACPI_OPERAND_OBJECT * ObjDesc,ACPI_WALK_STATE * WalkState)394 AcpiExReleaseMutex (
395 ACPI_OPERAND_OBJECT *ObjDesc,
396 ACPI_WALK_STATE *WalkState)
397 {
398 ACPI_STATUS Status = AE_OK;
399 UINT8 PreviousSyncLevel;
400 ACPI_THREAD_STATE *OwnerThread;
401
402
403 ACPI_FUNCTION_TRACE (ExReleaseMutex);
404
405
406 if (!ObjDesc)
407 {
408 return_ACPI_STATUS (AE_BAD_PARAMETER);
409 }
410
411 OwnerThread = ObjDesc->Mutex.OwnerThread;
412
413 /* The mutex must have been previously acquired in order to release it */
414
415 if (!OwnerThread)
416 {
417 ACPI_ERROR ((AE_INFO,
418 "Cannot release Mutex [%4.4s], not acquired",
419 AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
420 return_ACPI_STATUS (AE_AML_MUTEX_NOT_ACQUIRED);
421 }
422
423 /* Must have a valid thread ID */
424
425 if (!WalkState->Thread)
426 {
427 ACPI_ERROR ((AE_INFO,
428 "Cannot release Mutex [%4.4s], null thread info",
429 AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
430 return_ACPI_STATUS (AE_AML_INTERNAL);
431 }
432
433 /*
434 * The Mutex is owned, but this thread must be the owner.
435 * Special case for Global Lock, any thread can release
436 */
437 if ((OwnerThread->ThreadId != WalkState->Thread->ThreadId) &&
438 (ObjDesc != AcpiGbl_GlobalLockMutex))
439 {
440 ACPI_ERROR ((AE_INFO,
441 "Thread %u cannot release Mutex [%4.4s] acquired by thread %u",
442 (UINT32) WalkState->Thread->ThreadId,
443 AcpiUtGetNodeName (ObjDesc->Mutex.Node),
444 (UINT32) OwnerThread->ThreadId));
445 return_ACPI_STATUS (AE_AML_NOT_OWNER);
446 }
447
448 /*
449 * The sync level of the mutex must be equal to the current sync level. In
450 * other words, the current level means that at least one mutex at that
451 * level is currently being held. Attempting to release a mutex of a
452 * different level can only mean that the mutex ordering rule is being
453 * violated. This behavior is clarified in ACPI 4.0 specification.
454 */
455 if (ObjDesc->Mutex.SyncLevel != OwnerThread->CurrentSyncLevel)
456 {
457 ACPI_ERROR ((AE_INFO,
458 "Cannot release Mutex [%4.4s], SyncLevel mismatch: mutex %u current %u",
459 AcpiUtGetNodeName (ObjDesc->Mutex.Node),
460 ObjDesc->Mutex.SyncLevel, WalkState->Thread->CurrentSyncLevel));
461 return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
462 }
463
464 /*
465 * Get the previous SyncLevel from the head of the acquired mutex list.
466 * This handles the case where several mutexes at the same level have been
467 * acquired, but are not released in reverse order.
468 */
469 PreviousSyncLevel =
470 OwnerThread->AcquiredMutexList->Mutex.OriginalSyncLevel;
471
472 Status = AcpiExReleaseMutexObject (ObjDesc);
473 if (ACPI_FAILURE (Status))
474 {
475 return_ACPI_STATUS (Status);
476 }
477
478 if (ObjDesc->Mutex.AcquisitionDepth == 0)
479 {
480 /* Restore the previous SyncLevel */
481
482 OwnerThread->CurrentSyncLevel = PreviousSyncLevel;
483 }
484
485 return_ACPI_STATUS (Status);
486 }
487
488
489 /*******************************************************************************
490 *
491 * FUNCTION: AcpiExReleaseAllMutexes
492 *
493 * PARAMETERS: Thread - Current executing thread object
494 *
495 * RETURN: Status
496 *
497 * DESCRIPTION: Release all mutexes held by this thread
498 *
499 * NOTE: This function is called as the thread is exiting the interpreter.
500 * Mutexes are not released when an individual control method is exited, but
501 * only when the parent thread actually exits the interpreter. This allows one
502 * method to acquire a mutex, and a different method to release it, as long as
503 * this is performed underneath a single parent control method.
504 *
505 ******************************************************************************/
506
507 void
AcpiExReleaseAllMutexes(ACPI_THREAD_STATE * Thread)508 AcpiExReleaseAllMutexes (
509 ACPI_THREAD_STATE *Thread)
510 {
511 ACPI_OPERAND_OBJECT *Next = Thread->AcquiredMutexList;
512 ACPI_OPERAND_OBJECT *ObjDesc;
513
514
515 ACPI_FUNCTION_NAME (ExReleaseAllMutexes);
516
517
518 /* Traverse the list of owned mutexes, releasing each one */
519
520 while (Next)
521 {
522 ObjDesc = Next;
523 Next = ObjDesc->Mutex.Next;
524
525 ObjDesc->Mutex.Prev = NULL;
526 ObjDesc->Mutex.Next = NULL;
527 ObjDesc->Mutex.AcquisitionDepth = 0;
528
529 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
530 "Force-releasing held mutex: %p\n", ObjDesc));
531
532 /* Release the mutex, special case for Global Lock */
533
534 if (ObjDesc == AcpiGbl_GlobalLockMutex)
535 {
536 /* Ignore errors */
537
538 (void) AcpiEvReleaseGlobalLock ();
539 }
540 else
541 {
542 AcpiOsReleaseMutex (ObjDesc->Mutex.OsMutex);
543 }
544
545 /* Mark mutex unowned */
546
547 ObjDesc->Mutex.OwnerThread = NULL;
548 ObjDesc->Mutex.ThreadId = 0;
549
550 /* Update Thread SyncLevel (Last mutex is the important one) */
551
552 Thread->CurrentSyncLevel = ObjDesc->Mutex.OriginalSyncLevel;
553 }
554 }
555