[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / acpi / executer / exmutex.c


/******************************************************************************
 *
 * Module Name: exmutex - ASL Mutex Acquire/Release functions
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2006, R. Byron Moore
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include <acpi/acinterp.h>

#define _COMPONENT          ACPI_EXECUTER
ACPI_MODULE_NAME("exmutex")

/* Local prototypes */
static void
acpi_ex_link_mutex(union acpi_operand_object *obj_desc,
		   struct acpi_thread_state *thread);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_unlink_mutex
 *
 * PARAMETERS:  obj_desc            - The mutex to be unlinked
 *
 * RETURN:      None
 *
 * DESCRIPTION: Remove a mutex from the "acquired_mutex" list
 *
 ******************************************************************************/

void acpi_ex_unlink_mutex(union acpi_operand_object *obj_desc)
{
	struct acpi_thread_state *thread = obj_desc->mutex.owner_thread;

	if (!thread) {
		return;
	}

	/* Doubly linked list */

	if (obj_desc->mutex.next) {
		(obj_desc->mutex.next)->mutex.prev = obj_desc->mutex.prev;
	}

	if (obj_desc->mutex.prev) {
		(obj_desc->mutex.prev)->mutex.next = obj_desc->mutex.next;
	} else {
		thread->acquired_mutex_list = obj_desc->mutex.next;
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_link_mutex
 *
 * PARAMETERS:  obj_desc        - The mutex to be linked
 *              Thread          - Current executing thread object
 *
 * RETURN:      None
 *
 * DESCRIPTION: Add a mutex to the "acquired_mutex" list for this walk
 *
 ******************************************************************************/

static void
acpi_ex_link_mutex(union acpi_operand_object *obj_desc,
		   struct acpi_thread_state *thread)
{
	union acpi_operand_object *list_head;

	list_head = thread->acquired_mutex_list;

	/* This object will be the first object in the list */

	obj_desc->mutex.prev = NULL;
	obj_desc->mutex.next = list_head;

	/* Update old first object to point back to this object */

	if (list_head) {
		list_head->mutex.prev = obj_desc;
	}

	/* Update list head */

	thread->acquired_mutex_list = obj_desc;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_acquire_mutex
 *
 * PARAMETERS:  time_desc           - Timeout integer
 *              obj_desc            - Mutex object
 *              walk_state          - Current method execution state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Acquire an AML mutex
 *
 ******************************************************************************/

acpi_status
acpi_ex_acquire_mutex(union acpi_operand_object *time_desc,
		      union acpi_operand_object *obj_desc,
		      struct acpi_walk_state *walk_state)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE_PTR("ex_acquire_mutex", obj_desc);

	if (!obj_desc) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/* Sanity check -- we must have a valid thread ID */

	if (!walk_state->thread) {
		ACPI_ERROR((AE_INFO,
			    "Cannot acquire Mutex [%4.4s], null thread info",
			    acpi_ut_get_node_name(obj_desc->mutex.node)));
		return_ACPI_STATUS(AE_AML_INTERNAL);
	}

	/*
	 * Current Sync must be less than or equal to the sync level of the
	 * mutex.  This mechanism provides some deadlock prevention
	 */
	if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) {
		ACPI_ERROR((AE_INFO,
			    "Cannot acquire Mutex [%4.4s], incorrect sync_level",
			    acpi_ut_get_node_name(obj_desc->mutex.node)));
		return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
	}

	/* Support for multiple acquires by the owning thread */

	if (obj_desc->mutex.owner_thread) {

		/* Special case for Global Lock, allow all threads */

		if ((obj_desc->mutex.owner_thread->thread_id ==
		     walk_state->thread->thread_id) ||
		    (obj_desc->mutex.semaphore ==
		     acpi_gbl_global_lock_semaphore)) {
			/*
			 * The mutex is already owned by this thread,
			 * just increment the acquisition depth
			 */
			obj_desc->mutex.acquisition_depth++;
			return_ACPI_STATUS(AE_OK);
		}
	}

	/* Acquire the mutex, wait if necessary */

	status = acpi_ex_system_acquire_mutex(time_desc, obj_desc);
	if (ACPI_FAILURE(status)) {

		/* Includes failure from a timeout on time_desc */

		return_ACPI_STATUS(status);
	}

	/* Have the mutex: update mutex and walk info and save the sync_level */

	obj_desc->mutex.owner_thread = walk_state->thread;
	obj_desc->mutex.acquisition_depth = 1;
	obj_desc->mutex.original_sync_level =
	    walk_state->thread->current_sync_level;

	walk_state->thread->current_sync_level = obj_desc->mutex.sync_level;

	/* Link the mutex to the current thread for force-unlock at method exit */

	acpi_ex_link_mutex(obj_desc, walk_state->thread);

	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_release_mutex
 *
 * PARAMETERS:  obj_desc            - The object descriptor for this op
 *              walk_state          - Current method execution state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Release a previously acquired Mutex.
 *
 ******************************************************************************/

acpi_status
acpi_ex_release_mutex(union acpi_operand_object *obj_desc,
		      struct acpi_walk_state *walk_state)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE("ex_release_mutex");

	if (!obj_desc) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/* The mutex must have been previously acquired in order to release it */

	if (!obj_desc->mutex.owner_thread) {
		ACPI_ERROR((AE_INFO,
			    "Cannot release Mutex [%4.4s], not acquired",
			    acpi_ut_get_node_name(obj_desc->mutex.node)));
		return_ACPI_STATUS(AE_AML_MUTEX_NOT_ACQUIRED);
	}

	/* Sanity check -- we must have a valid thread ID */

	if (!walk_state->thread) {
		ACPI_ERROR((AE_INFO,
			    "Cannot release Mutex [%4.4s], null thread info",
			    acpi_ut_get_node_name(obj_desc->mutex.node)));
		return_ACPI_STATUS(AE_AML_INTERNAL);
	}

	/*
	 * The Mutex is owned, but this thread must be the owner.
	 * Special case for Global Lock, any thread can release
	 */
	if ((obj_desc->mutex.owner_thread->thread_id !=
	     walk_state->thread->thread_id)
	    && (obj_desc->mutex.semaphore != acpi_gbl_global_lock_semaphore)) {
		ACPI_ERROR((AE_INFO,
			    "Thread %X cannot release Mutex [%4.4s] acquired by thread %X",
			    walk_state->thread->thread_id,
			    acpi_ut_get_node_name(obj_desc->mutex.node),
			    obj_desc->mutex.owner_thread->thread_id));
		return_ACPI_STATUS(AE_AML_NOT_OWNER);
	}

	/*
	 * The sync level of the mutex must be less than or
	 * equal to the current sync level
	 */
	if (obj_desc->mutex.sync_level > walk_state->thread->current_sync_level) {
		ACPI_ERROR((AE_INFO,
			    "Cannot release Mutex [%4.4s], incorrect sync_level",
			    acpi_ut_get_node_name(obj_desc->mutex.node)));
		return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
	}

	/* Match multiple Acquires with multiple Releases */

	obj_desc->mutex.acquisition_depth--;
	if (obj_desc->mutex.acquisition_depth != 0) {

		/* Just decrement the depth and return */

		return_ACPI_STATUS(AE_OK);
	}

	/* Unlink the mutex from the owner's list */

	acpi_ex_unlink_mutex(obj_desc);

	/* Release the mutex */

	status = acpi_ex_system_release_mutex(obj_desc);

	/* Update the mutex and walk state, restore sync_level before acquire */

	obj_desc->mutex.owner_thread = NULL;
	walk_state->thread->current_sync_level =
	    obj_desc->mutex.original_sync_level;

	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_release_all_mutexes
 *
 * PARAMETERS:  Thread          - Current executing thread object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Release all mutexes held by this thread
 *
 ******************************************************************************/

void acpi_ex_release_all_mutexes(struct acpi_thread_state *thread)
{
	union acpi_operand_object *next = thread->acquired_mutex_list;
	union acpi_operand_object *this;
	acpi_status status;

	ACPI_FUNCTION_ENTRY();

	/* Traverse the list of owned mutexes, releasing each one */

	while (next) {
		this = next;
		next = this->mutex.next;

		this->mutex.acquisition_depth = 1;
		this->mutex.prev = NULL;
		this->mutex.next = NULL;

		/* Release the mutex */

		status = acpi_ex_system_release_mutex(this);
		if (ACPI_FAILURE(status)) {
			continue;
		}

		/* Mark mutex unowned */

		this->mutex.owner_thread = NULL;

		/* Update Thread sync_level (Last mutex is the important one) */

		thread->current_sync_level = this->mutex.original_sync_level;
	}
}
Commit	Line	Data
1da177e4 LT	1
	2	/******************************************************************************
	3	*
	4	* Module Name: exmutex - ASL Mutex Acquire/Release functions
	5	*
	6	*****************************************************************************/
	7
	8	/*
4a90c7e8	9	* Copyright (C) 2000 - 2006, R. Byron Moore
1da177e4 LT	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
1da177e4 LT	45	#include <acpi/acpi.h>
	46	#include <acpi/acinterp.h>
	47
	48	#define _COMPONENT ACPI_EXECUTER
4be44fcd	49	ACPI_MODULE_NAME("exmutex")
1da177e4	50
44f6c012	51	/* Local prototypes */
44f6c012	52	static void
4be44fcd LB	53	acpi_ex_link_mutex(union acpi_operand_object *obj_desc,
4be44fcd LB	54	struct acpi_thread_state *thread);
1da177e4 LT	55
	56	/*******************************************************************************
	57	*
	58	* FUNCTION: acpi_ex_unlink_mutex
	59	*
	60	* PARAMETERS: obj_desc - The mutex to be unlinked
	61	*
44f6c012	62	* RETURN: None
1da177e4 LT	63	*
	64	* DESCRIPTION: Remove a mutex from the "acquired_mutex" list
	65	*
	66	******************************************************************************/
	67
4be44fcd	68	void acpi_ex_unlink_mutex(union acpi_operand_object *obj_desc)
1da177e4	69	{
4be44fcd	70	struct acpi_thread_state *thread = obj_desc->mutex.owner_thread;
1da177e4 LT	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;
4be44fcd	84	} else {
1da177e4 LT	85	thread->acquired_mutex_list = obj_desc->mutex.next;
	86	}
	87	}
	88
1da177e4 LT	89	/*******************************************************************************
	90	*
	91	* FUNCTION: acpi_ex_link_mutex
	92	*
44f6c012 RM	93	* PARAMETERS: obj_desc - The mutex to be linked
44f6c012 RM	94	* Thread - Current executing thread object
1da177e4	95	*
44f6c012	96	* RETURN: None
1da177e4 LT	97	*
	98	* DESCRIPTION: Add a mutex to the "acquired_mutex" list for this walk
	99	*
	100	******************************************************************************/
	101
44f6c012	102	static void
4be44fcd LB	103	acpi_ex_link_mutex(union acpi_operand_object *obj_desc,
4be44fcd LB	104	struct acpi_thread_state *thread)
1da177e4	105	{
4be44fcd	106	union acpi_operand_object *list_head;
1da177e4 LT	107
	108	list_head = thread->acquired_mutex_list;
	109
	110	/* This object will be the first object in the list */
	111
	112	obj_desc->mutex.prev = NULL;
	113	obj_desc->mutex.next = list_head;
	114
	115	/* Update old first object to point back to this object */
	116
	117	if (list_head) {
	118	list_head->mutex.prev = obj_desc;
	119	}
	120
	121	/* Update list head */
	122
	123	thread->acquired_mutex_list = obj_desc;
	124	}
	125
1da177e4 LT	126	/*******************************************************************************
	127	*
	128	* FUNCTION: acpi_ex_acquire_mutex
	129	*
44f6c012 RM	130	* PARAMETERS: time_desc - Timeout integer
	131	* obj_desc - Mutex object
	132	* walk_state - Current method execution state
1da177e4 LT	133	*
	134	* RETURN: Status
	135	*
	136	* DESCRIPTION: Acquire an AML mutex
	137	*
	138	******************************************************************************/
	139
	140	acpi_status
4be44fcd LB	141	acpi_ex_acquire_mutex(union acpi_operand_object *time_desc,
	142	union acpi_operand_object *obj_desc,
	143	struct acpi_walk_state *walk_state)
1da177e4	144	{
4be44fcd	145	acpi_status status;
1da177e4	146
4be44fcd	147	ACPI_FUNCTION_TRACE_PTR("ex_acquire_mutex", obj_desc);
1da177e4 LT	148
1da177e4 LT	149	if (!obj_desc) {
4be44fcd	150	return_ACPI_STATUS(AE_BAD_PARAMETER);
1da177e4 LT	151	}
	152
	153	/* Sanity check -- we must have a valid thread ID */
	154
	155	if (!walk_state->thread) {
b8e4d893 BM	156	ACPI_ERROR((AE_INFO,
	157	"Cannot acquire Mutex [%4.4s], null thread info",
	158	acpi_ut_get_node_name(obj_desc->mutex.node)));
4be44fcd	159	return_ACPI_STATUS(AE_AML_INTERNAL);
1da177e4 LT	160	}
	161
	162	/*
	163	* Current Sync must be less than or equal to the sync level of the
	164	* mutex. This mechanism provides some deadlock prevention
	165	*/
	166	if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) {
b8e4d893 BM	167	ACPI_ERROR((AE_INFO,
	168	"Cannot acquire Mutex [%4.4s], incorrect sync_level",
	169	acpi_ut_get_node_name(obj_desc->mutex.node)));
4be44fcd	170	return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
1da177e4 LT	171	}
	172
	173	/* Support for multiple acquires by the owning thread */
	174
	175	if (obj_desc->mutex.owner_thread) {
52fc0b02	176
1da177e4 LT	177	/* Special case for Global Lock, allow all threads */
1da177e4 LT	178
44f6c012	179	if ((obj_desc->mutex.owner_thread->thread_id ==
4be44fcd LB	180	walk_state->thread->thread_id) \|\|
	181	(obj_desc->mutex.semaphore ==
	182	acpi_gbl_global_lock_semaphore)) {
1da177e4 LT	183	/*
	184	* The mutex is already owned by this thread,
	185	* just increment the acquisition depth
	186	*/
	187	obj_desc->mutex.acquisition_depth++;
4be44fcd	188	return_ACPI_STATUS(AE_OK);
1da177e4 LT	189	}
	190	}
	191
	192	/* Acquire the mutex, wait if necessary */
	193
4be44fcd LB	194	status = acpi_ex_system_acquire_mutex(time_desc, obj_desc);
4be44fcd LB	195	if (ACPI_FAILURE(status)) {
52fc0b02	196
1da177e4 LT	197	/* Includes failure from a timeout on time_desc */
1da177e4 LT	198
4be44fcd	199	return_ACPI_STATUS(status);
1da177e4 LT	200	}
	201
	202	/* Have the mutex: update mutex and walk info and save the sync_level */
	203
4be44fcd	204	obj_desc->mutex.owner_thread = walk_state->thread;
1da177e4	205	obj_desc->mutex.acquisition_depth = 1;
4be44fcd LB	206	obj_desc->mutex.original_sync_level =
4be44fcd LB	207	walk_state->thread->current_sync_level;
1da177e4 LT	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
4be44fcd	213	acpi_ex_link_mutex(obj_desc, walk_state->thread);
1da177e4	214
4be44fcd	215	return_ACPI_STATUS(AE_OK);
1da177e4 LT	216	}
1da177e4 LT	217
1da177e4 LT	218	/*******************************************************************************
	219	*
	220	* FUNCTION: acpi_ex_release_mutex
	221	*
	222	* PARAMETERS: obj_desc - The object descriptor for this op
44f6c012	223	* walk_state - Current method execution state
1da177e4 LT	224	*
	225	* RETURN: Status
	226	*
	227	* DESCRIPTION: Release a previously acquired Mutex.
	228	*
	229	******************************************************************************/
	230
	231	acpi_status
4be44fcd LB	232	acpi_ex_release_mutex(union acpi_operand_object *obj_desc,
4be44fcd LB	233	struct acpi_walk_state *walk_state)
1da177e4	234	{
4be44fcd	235	acpi_status status;
1da177e4	236
4be44fcd	237	ACPI_FUNCTION_TRACE("ex_release_mutex");
1da177e4 LT	238
1da177e4 LT	239	if (!obj_desc) {
4be44fcd	240	return_ACPI_STATUS(AE_BAD_PARAMETER);
1da177e4 LT	241	}
	242
	243	/* The mutex must have been previously acquired in order to release it */
	244
	245	if (!obj_desc->mutex.owner_thread) {
b8e4d893 BM	246	ACPI_ERROR((AE_INFO,
	247	"Cannot release Mutex [%4.4s], not acquired",
	248	acpi_ut_get_node_name(obj_desc->mutex.node)));
4be44fcd	249	return_ACPI_STATUS(AE_AML_MUTEX_NOT_ACQUIRED);
1da177e4 LT	250	}
	251
	252	/* Sanity check -- we must have a valid thread ID */
	253
	254	if (!walk_state->thread) {
b8e4d893 BM	255	ACPI_ERROR((AE_INFO,
	256	"Cannot release Mutex [%4.4s], null thread info",
	257	acpi_ut_get_node_name(obj_desc->mutex.node)));
4be44fcd	258	return_ACPI_STATUS(AE_AML_INTERNAL);
1da177e4 LT	259	}
	260
	261	/*
	262	* The Mutex is owned, but this thread must be the owner.
	263	* Special case for Global Lock, any thread can release
	264	*/
4be44fcd LB	265	if ((obj_desc->mutex.owner_thread->thread_id !=
	266	walk_state->thread->thread_id)
	267	&& (obj_desc->mutex.semaphore != acpi_gbl_global_lock_semaphore)) {
b8e4d893 BM	268	ACPI_ERROR((AE_INFO,
	269	"Thread %X cannot release Mutex [%4.4s] acquired by thread %X",
	270	walk_state->thread->thread_id,
	271	acpi_ut_get_node_name(obj_desc->mutex.node),
	272	obj_desc->mutex.owner_thread->thread_id));
4be44fcd	273	return_ACPI_STATUS(AE_AML_NOT_OWNER);
1da177e4 LT	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) {
b8e4d893 BM	281	ACPI_ERROR((AE_INFO,
	282	"Cannot release Mutex [%4.4s], incorrect sync_level",
	283	acpi_ut_get_node_name(obj_desc->mutex.node)));
4be44fcd	284	return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
1da177e4 LT	285	}
	286
	287	/* Match multiple Acquires with multiple Releases */
	288
	289	obj_desc->mutex.acquisition_depth--;
	290	if (obj_desc->mutex.acquisition_depth != 0) {
52fc0b02	291
1da177e4 LT	292	/* Just decrement the depth and return */
1da177e4 LT	293
4be44fcd	294	return_ACPI_STATUS(AE_OK);
1da177e4 LT	295	}
	296
	297	/* Unlink the mutex from the owner's list */
	298
4be44fcd	299	acpi_ex_unlink_mutex(obj_desc);
1da177e4 LT	300
	301	/* Release the mutex */
	302
4be44fcd	303	status = acpi_ex_system_release_mutex(obj_desc);
1da177e4 LT	304
	305	/* Update the mutex and walk state, restore sync_level before acquire */
	306
	307	obj_desc->mutex.owner_thread = NULL;
4be44fcd LB	308	walk_state->thread->current_sync_level =
4be44fcd LB	309	obj_desc->mutex.original_sync_level;
1da177e4	310
4be44fcd	311	return_ACPI_STATUS(status);
1da177e4 LT	312	}
1da177e4 LT	313
1da177e4 LT	314	/*******************************************************************************
	315	*
	316	* FUNCTION: acpi_ex_release_all_mutexes
	317	*
44f6c012	318	* PARAMETERS: Thread - Current executing thread object
1da177e4 LT	319	*
	320	* RETURN: Status
	321	*
44f6c012	322	* DESCRIPTION: Release all mutexes held by this thread
1da177e4 LT	323	*
	324	******************************************************************************/
	325
4be44fcd	326	void acpi_ex_release_all_mutexes(struct acpi_thread_state *thread)
1da177e4	327	{
4be44fcd LB	328	union acpi_operand_object *next = thread->acquired_mutex_list;
	329	union acpi_operand_object *this;
	330	acpi_status status;
1da177e4	331
4be44fcd	332	ACPI_FUNCTION_ENTRY();
1da177e4 LT	333
	334	/* Traverse the list of owned mutexes, releasing each one */
	335
	336	while (next) {
	337	this = next;
	338	next = this->mutex.next;
	339
	340	this->mutex.acquisition_depth = 1;
4be44fcd LB	341	this->mutex.prev = NULL;
4be44fcd LB	342	this->mutex.next = NULL;
1da177e4	343
4be44fcd	344	/* Release the mutex */
1da177e4	345
4be44fcd LB	346	status = acpi_ex_system_release_mutex(this);
4be44fcd LB	347	if (ACPI_FAILURE(status)) {
1da177e4 LT	348	continue;
	349	}
	350
	351	/* Mark mutex unowned */
	352
	353	this->mutex.owner_thread = NULL;
	354
	355	/* Update Thread sync_level (Last mutex is the important one) */
	356
	357	thread->current_sync_level = this->mutex.original_sync_level;
	358	}
	359	}