/******************************************************************************* * * Module Name: utmutex - local mutex support * ******************************************************************************/ /* * Copyright (C) 2000 - 2007, 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> #define _COMPONENT ACPI_UTILITIES ACPI_MODULE_NAME("utmutex") /* Local prototypes */ static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id); static acpi_status acpi_ut_delete_mutex(acpi_mutex_handle mutex_id); /******************************************************************************* * * FUNCTION: acpi_ut_mutex_initialize * * PARAMETERS: None. * * RETURN: Status * * DESCRIPTION: Create the system mutex objects. * ******************************************************************************/ acpi_status acpi_ut_mutex_initialize(void) { u32 i; acpi_status status; ACPI_FUNCTION_TRACE(ut_mutex_initialize); /* * Create each of the predefined mutex objects */ for (i = 0; i < ACPI_NUM_MUTEX; i++) { status = acpi_ut_create_mutex(i); if (ACPI_FAILURE(status)) { return_ACPI_STATUS(status); } } /* Create the spinlocks for use at interrupt level */ spin_lock_init(acpi_gbl_gpe_lock); spin_lock_init(acpi_gbl_hardware_lock); return_ACPI_STATUS(status); } /******************************************************************************* * * FUNCTION: acpi_ut_mutex_terminate * * PARAMETERS: None. * * RETURN: None. * * DESCRIPTION: Delete all of the system mutex objects. * ******************************************************************************/ void acpi_ut_mutex_terminate(void) { u32 i; ACPI_FUNCTION_TRACE(ut_mutex_terminate); /* * Delete each predefined mutex object */ for (i = 0; i < ACPI_NUM_MUTEX; i++) { (void)acpi_ut_delete_mutex(i); } /* Delete the spinlocks */ acpi_os_delete_lock(acpi_gbl_gpe_lock); acpi_os_delete_lock(acpi_gbl_hardware_lock); return_VOID; } /******************************************************************************* * * FUNCTION: acpi_ut_create_mutex * * PARAMETERS: mutex_iD - ID of the mutex to be created * * RETURN: Status * * DESCRIPTION: Create a mutex object. * ******************************************************************************/ static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id) { acpi_status status = AE_OK; ACPI_FUNCTION_TRACE_U32(ut_create_mutex, mutex_id); if (mutex_id > ACPI_MAX_MUTEX) { return_ACPI_STATUS(AE_BAD_PARAMETER); } if (!acpi_gbl_mutex_info[mutex_id].mutex) { status = acpi_os_create_mutex(&acpi_gbl_mutex_info[mutex_id].mutex); acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED; acpi_gbl_mutex_info[mutex_id].use_count = 0; } return_ACPI_STATUS(status); } /******************************************************************************* * * FUNCTION: acpi_ut_delete_mutex * * PARAMETERS: mutex_iD - ID of the mutex to be deleted * * RETURN: Status * * DESCRIPTION: Delete a mutex object. * ******************************************************************************/ static acpi_status acpi_ut_delete_mutex(acpi_mutex_handle mutex_id) { ACPI_FUNCTION_TRACE_U32(ut_delete_mutex, mutex_id); if (mutex_id > ACPI_MAX_MUTEX) { return_ACPI_STATUS(AE_BAD_PARAMETER); } acpi_os_delete_mutex(acpi_gbl_mutex_info[mutex_id].mutex); acpi_gbl_mutex_info[mutex_id].mutex = NULL; acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED; return_ACPI_STATUS(AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ut_acquire_mutex * * PARAMETERS: mutex_iD - ID of the mutex to be acquired * * RETURN: Status * * DESCRIPTION: Acquire a mutex object. * ******************************************************************************/ acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id) { acpi_status status; acpi_thread_id this_thread_id; ACPI_FUNCTION_NAME(ut_acquire_mutex); if (mutex_id > ACPI_MAX_MUTEX) { return (AE_BAD_PARAMETER); } this_thread_id = acpi_os_get_thread_id(); #ifdef ACPI_MUTEX_DEBUG { u32 i; /* * Mutex debug code, for internal debugging only. * * Deadlock prevention. Check if this thread owns any mutexes of value * greater than or equal to this one. If so, the thread has violated * the mutex ordering rule. This indicates a coding error somewhere in * the ACPI subsystem code. */ for (i = mutex_id; i < ACPI_MAX_MUTEX; i++) { if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) { if (i == mutex_id) { ACPI_ERROR((AE_INFO, "Mutex [%s] already acquired by this thread [%X]", acpi_ut_get_mutex_name (mutex_id), this_thread_id)); return (AE_ALREADY_ACQUIRED); } ACPI_ERROR((AE_INFO, "Invalid acquire order: Thread %X owns [%s], wants [%s]", this_thread_id, acpi_ut_get_mutex_name(i), acpi_ut_get_mutex_name(mutex_id))); return (AE_ACQUIRE_DEADLOCK); } } } #endif ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %lX attempting to acquire Mutex [%s]\n", (unsigned long) this_thread_id, acpi_ut_get_mutex_name(mutex_id))); status = acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex, ACPI_WAIT_FOREVER); if (ACPI_SUCCESS(status)) { ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %lX acquired Mutex [%s]\n", (unsigned long) this_thread_id, acpi_ut_get_mutex_name(mutex_id))); acpi_gbl_mutex_info[mutex_id].use_count++; acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id; } else { ACPI_EXCEPTION((AE_INFO, status, "Thread %lX could not acquire Mutex [%X]", (unsigned long) this_thread_id, mutex_id)); } return (status); } /******************************************************************************* * * FUNCTION: acpi_ut_release_mutex * * PARAMETERS: mutex_iD - ID of the mutex to be released * * RETURN: Status * * DESCRIPTION: Release a mutex object. * ******************************************************************************/ acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id) { acpi_thread_id this_thread_id; ACPI_FUNCTION_NAME(ut_release_mutex); this_thread_id = acpi_os_get_thread_id(); ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %lX releasing Mutex [%s]\n", (unsigned long) this_thread_id, acpi_ut_get_mutex_name(mutex_id))); if (mutex_id > ACPI_MAX_MUTEX) { return (AE_BAD_PARAMETER); } /* * Mutex must be acquired in order to release it! */ if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) { ACPI_ERROR((AE_INFO, "Mutex [%X] is not acquired, cannot release", mutex_id)); return (AE_NOT_ACQUIRED); } #ifdef ACPI_MUTEX_DEBUG { u32 i; /* * Mutex debug code, for internal debugging only. * * Deadlock prevention. Check if this thread owns any mutexes of value * greater than this one. If so, the thread has violated the mutex * ordering rule. This indicates a coding error somewhere in * the ACPI subsystem code. */ for (i = mutex_id; i < ACPI_MAX_MUTEX; i++) { if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) { if (i == mutex_id) { continue; } ACPI_ERROR((AE_INFO, "Invalid release order: owns [%s], releasing [%s]", acpi_ut_get_mutex_name(i), acpi_ut_get_mutex_name(mutex_id))); return (AE_RELEASE_DEADLOCK); } } } #endif /* Mark unlocked FIRST */ acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED; acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex); return (AE_OK); }