patch-2.4.6 linux/drivers/acpi/executer/exmutex.c
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- Lines: 282
- Date:
Wed Jun 20 17:47:40 2001
- Orig file:
v2.4.5/linux/drivers/acpi/executer/exmutex.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.4.5/linux/drivers/acpi/executer/exmutex.c linux/drivers/acpi/executer/exmutex.c
@@ -0,0 +1,281 @@
+
+/******************************************************************************
+ *
+ * Module Name: exmutex - ASL Mutex Acquire/Release functions
+ * $Revision: 5 $
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000, 2001 R. Byron Moore
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+
+#include "acpi.h"
+#include "acinterp.h"
+#include "acnamesp.h"
+#include "achware.h"
+#include "acevents.h"
+
+#define _COMPONENT ACPI_EXECUTER
+ 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 (
+ ACPI_OPERAND_OBJECT *obj_desc)
+{
+
+ 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;
+ }
+}
+
+
+/*******************************************************************************
+ *
+ * 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 (
+ ACPI_OPERAND_OBJECT *obj_desc,
+ ACPI_OPERAND_OBJECT *list_head)
+{
+
+ /* This object will be the first object in the list */
+
+ obj_desc->mutex.prev = list_head;
+ obj_desc->mutex.next = list_head->mutex.next;
+
+ /* Update old first object to point back to this object */
+
+ if (list_head->mutex.next) {
+ (list_head->mutex.next)->mutex.prev = obj_desc;
+ }
+
+ /* Update list head */
+
+ list_head->mutex.next = 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 (
+ ACPI_OPERAND_OBJECT *time_desc,
+ ACPI_OPERAND_OBJECT *obj_desc,
+ ACPI_WALK_STATE *walk_state)
+{
+ ACPI_STATUS status;
+
+
+ if (!obj_desc) {
+ return (AE_BAD_PARAMETER);
+ }
+
+ /*
+ * Current Sync must be less than or equal to the sync level of the
+ * mutex. This mechanism provides some deadlock prevention
+ */
+ if (walk_state->current_sync_level > obj_desc->mutex.sync_level) {
+ return (AE_AML_MUTEX_ORDER);
+ }
+
+ /*
+ * If the mutex is already owned by this thread,
+ * just increment the acquisition depth
+ */
+ if (obj_desc->mutex.owner == walk_state) {
+ obj_desc->mutex.acquisition_depth++;
+ return (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 (status);
+ }
+
+ /* Have the mutex, update mutex and walk info */
+
+ obj_desc->mutex.owner = walk_state;
+ obj_desc->mutex.acquisition_depth = 1;
+ walk_state->current_sync_level = obj_desc->mutex.sync_level;
+
+ /* Link the mutex to the walk state for force-unlock at method exit */
+
+ acpi_ex_link_mutex (obj_desc, (ACPI_OPERAND_OBJECT *)
+ &(walk_state->walk_list->acquired_mutex_list));
+
+ return (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 (
+ ACPI_OPERAND_OBJECT *obj_desc,
+ ACPI_WALK_STATE *walk_state)
+{
+ ACPI_STATUS status;
+
+
+ if (!obj_desc) {
+ return (AE_BAD_PARAMETER);
+ }
+
+ /* The mutex must have been previously acquired in order to release it */
+
+ if (!obj_desc->mutex.owner) {
+ return (AE_AML_MUTEX_NOT_ACQUIRED);
+ }
+
+ /* The Mutex is owned, but this thread must be the owner */
+
+ if (obj_desc->mutex.owner != walk_state) {
+ return (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->current_sync_level) {
+ return (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 (AE_OK);
+ }
+
+
+ /* Release the mutex */
+
+ status = acpi_ex_system_release_mutex (obj_desc);
+
+ /* Update the mutex and walk state */
+
+ obj_desc->mutex.owner = NULL;
+ walk_state->current_sync_level = obj_desc->mutex.sync_level;
+
+ /* Unlink the mutex from the owner's list */
+
+ acpi_ex_unlink_mutex (obj_desc);
+
+ return (status);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION: Acpi_ex_release_all_mutexes
+ *
+ * PARAMETERS: *Mutex_list - Head of the mutex list
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Release all mutexes in the list
+ *
+ ******************************************************************************/
+
+ACPI_STATUS
+acpi_ex_release_all_mutexes (
+ ACPI_OPERAND_OBJECT *list_head)
+{
+ ACPI_OPERAND_OBJECT *next = list_head->mutex.next;
+ ACPI_OPERAND_OBJECT *this;
+
+
+ /*
+ * Traverse the list of owned mutexes, releasing each one.
+ */
+ while (next) {
+ this = next;
+ next = this->mutex.next;
+
+ /* Mark mutex un-owned */
+
+ this->mutex.owner = NULL;
+ this->mutex.prev = NULL;
+ this->mutex.next = NULL;
+ this->mutex.acquisition_depth = 0;
+
+ /* Release the mutex */
+
+ acpi_ex_system_release_mutex (this);
+ }
+
+ return (AE_OK);
+}
+
+
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