diff options
Diffstat (limited to 'drivers/acpi/executer/exmutex.c')
| -rw-r--r-- | drivers/acpi/executer/exmutex.c | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/drivers/acpi/executer/exmutex.c b/drivers/acpi/executer/exmutex.c new file mode 100644 index 0000000..68c4bb1 --- /dev/null +++ b/drivers/acpi/executer/exmutex.c @@ -0,0 +1,363 @@ + +/****************************************************************************** + * + * Module Name: exmutex - ASL Mutex Acquire/Release functions + * + *****************************************************************************/ + +/* + * Copyright (C) 2000 - 2005, 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") + + +/******************************************************************************* + * + * FUNCTION: acpi_ex_unlink_mutex + * + * PARAMETERS: obj_desc - The mutex to be unlinked + * + * RETURN: Status + * + * 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 + * list_head - head of the "acquired_mutex" list + * + * RETURN: Status + * + * DESCRIPTION: Add a mutex to the "acquired_mutex" list for this walk + * + ******************************************************************************/ + +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 - The 'time to delay' object descriptor + * obj_desc - The object descriptor for this op + * + * 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_REPORT_ERROR (("Cannot acquire Mutex [%4.4s], null thread info\n", + 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_REPORT_ERROR (("Cannot acquire Mutex [%4.4s], incorrect sync_level\n", + 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 + * + * 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_REPORT_ERROR (("Cannot release Mutex [%4.4s], not acquired\n", + 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_REPORT_ERROR (("Cannot release Mutex [%4.4s], null thread info\n", + 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_REPORT_ERROR (( + "Thread %X cannot release Mutex [%4.4s] acquired by thread %X\n", + 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_REPORT_ERROR (("Cannot release Mutex [%4.4s], incorrect sync_level\n", + 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: mutex_list - Head of the mutex list + * + * RETURN: Status + * + * DESCRIPTION: Release all mutexes in the list + * + ******************************************************************************/ + +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; + } +} + + |
