linux/drivers/acpi/acpica/nswalk.c
Bob Moore a8357b0c95 ACPICA: Update all ACPICA copyrights and signons to 2010
Add 2010 copyright to all module headers and signons, including
the Linux header. This affects virtually every file in the ACPICA
core subsystem, iASL compiler, and all utilities.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-01-22 12:30:05 -05:00

368 lines
11 KiB
C

/******************************************************************************
*
* Module Name: nswalk - Functions for walking the ACPI namespace
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2010, Intel Corp.
* 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 "accommon.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("nswalk")
/*******************************************************************************
*
* FUNCTION: acpi_ns_get_next_node
*
* PARAMETERS: parent_node - Parent node whose children we are
* getting
* child_node - Previous child that was found.
* The NEXT child will be returned
*
* RETURN: struct acpi_namespace_node - Pointer to the NEXT child or NULL if
* none is found.
*
* DESCRIPTION: Return the next peer node within the namespace. If Handle
* is valid, Scope is ignored. Otherwise, the first node
* within Scope is returned.
*
******************************************************************************/
struct acpi_namespace_node *acpi_ns_get_next_node(struct acpi_namespace_node
*parent_node,
struct acpi_namespace_node
*child_node)
{
ACPI_FUNCTION_ENTRY();
if (!child_node) {
/* It's really the parent's _scope_ that we want */
return parent_node->child;
}
/*
* Get the next node.
*
* If we are at the end of this peer list, return NULL
*/
if (child_node->flags & ANOBJ_END_OF_PEER_LIST) {
return NULL;
}
/* Otherwise just return the next peer */
return child_node->peer;
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_get_next_node_typed
*
* PARAMETERS: Type - Type of node to be searched for
* parent_node - Parent node whose children we are
* getting
* child_node - Previous child that was found.
* The NEXT child will be returned
*
* RETURN: struct acpi_namespace_node - Pointer to the NEXT child or NULL if
* none is found.
*
* DESCRIPTION: Return the next peer node within the namespace. If Handle
* is valid, Scope is ignored. Otherwise, the first node
* within Scope is returned.
*
******************************************************************************/
struct acpi_namespace_node *acpi_ns_get_next_node_typed(acpi_object_type type,
struct
acpi_namespace_node
*parent_node,
struct
acpi_namespace_node
*child_node)
{
struct acpi_namespace_node *next_node = NULL;
ACPI_FUNCTION_ENTRY();
next_node = acpi_ns_get_next_node(parent_node, child_node);
/* If any type is OK, we are done */
if (type == ACPI_TYPE_ANY) {
/* next_node is NULL if we are at the end-of-list */
return (next_node);
}
/* Must search for the node -- but within this scope only */
while (next_node) {
/* If type matches, we are done */
if (next_node->type == type) {
return (next_node);
}
/* Otherwise, move on to the next node */
next_node = acpi_ns_get_next_valid_node(next_node);
}
/* Not found */
return (NULL);
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_walk_namespace
*
* PARAMETERS: Type - acpi_object_type to search for
* start_node - Handle in namespace where search begins
* max_depth - Depth to which search is to reach
* Flags - Whether to unlock the NS before invoking
* the callback routine
* pre_order_visit - Called during tree pre-order visit
* when an object of "Type" is found
* post_order_visit - Called during tree post-order visit
* when an object of "Type" is found
* Context - Passed to user function(s) above
* return_value - from the user_function if terminated
* early. Otherwise, returns NULL.
* RETURNS: Status
*
* DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
* starting (and ending) at the node specified by start_handle.
* The callback function is called whenever a node that matches
* the type parameter is found. If the callback function returns
* a non-zero value, the search is terminated immediately and
* this value is returned to the caller.
*
* The point of this procedure is to provide a generic namespace
* walk routine that can be called from multiple places to
* provide multiple services; the callback function(s) can be
* tailored to each task, whether it is a print function,
* a compare function, etc.
*
******************************************************************************/
acpi_status
acpi_ns_walk_namespace(acpi_object_type type,
acpi_handle start_node,
u32 max_depth,
u32 flags,
acpi_walk_callback pre_order_visit,
acpi_walk_callback post_order_visit,
void *context, void **return_value)
{
acpi_status status;
acpi_status mutex_status;
struct acpi_namespace_node *child_node;
struct acpi_namespace_node *parent_node;
acpi_object_type child_type;
u32 level;
u8 node_previously_visited = FALSE;
ACPI_FUNCTION_TRACE(ns_walk_namespace);
/* Special case for the namespace Root Node */
if (start_node == ACPI_ROOT_OBJECT) {
start_node = acpi_gbl_root_node;
}
/* Null child means "get first node" */
parent_node = start_node;
child_node = acpi_ns_get_next_node(parent_node, NULL);
child_type = ACPI_TYPE_ANY;
level = 1;
/*
* Traverse the tree of nodes until we bubble back up to where we
* started. When Level is zero, the loop is done because we have
* bubbled up to (and passed) the original parent handle (start_entry)
*/
while (level > 0 && child_node) {
status = AE_OK;
/* Found next child, get the type if we are not searching for ANY */
if (type != ACPI_TYPE_ANY) {
child_type = child_node->type;
}
/*
* Ignore all temporary namespace nodes (created during control
* method execution) unless told otherwise. These temporary nodes
* can cause a race condition because they can be deleted during
* the execution of the user function (if the namespace is
* unlocked before invocation of the user function.) Only the
* debugger namespace dump will examine the temporary nodes.
*/
if ((child_node->flags & ANOBJ_TEMPORARY) &&
!(flags & ACPI_NS_WALK_TEMP_NODES)) {
status = AE_CTRL_DEPTH;
}
/* Type must match requested type */
else if (child_type == type) {
/*
* Found a matching node, invoke the user callback function.
* Unlock the namespace if flag is set.
*/
if (flags & ACPI_NS_WALK_UNLOCK) {
mutex_status =
acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(mutex_status)) {
return_ACPI_STATUS(mutex_status);
}
}
/*
* Invoke the user function, either pre-order or post-order
* or both.
*/
if (!node_previously_visited) {
if (pre_order_visit) {
status =
pre_order_visit(child_node, level,
context,
return_value);
}
} else {
if (post_order_visit) {
status =
post_order_visit(child_node, level,
context,
return_value);
}
}
if (flags & ACPI_NS_WALK_UNLOCK) {
mutex_status =
acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(mutex_status)) {
return_ACPI_STATUS(mutex_status);
}
}
switch (status) {
case AE_OK:
case AE_CTRL_DEPTH:
/* Just keep going */
break;
case AE_CTRL_TERMINATE:
/* Exit now, with OK status */
return_ACPI_STATUS(AE_OK);
default:
/* All others are valid exceptions */
return_ACPI_STATUS(status);
}
}
/*
* Depth first search: Attempt to go down another level in the
* namespace if we are allowed to. Don't go any further if we have
* reached the caller specified maximum depth or if the user
* function has specified that the maximum depth has been reached.
*/
if (!node_previously_visited &&
(level < max_depth) && (status != AE_CTRL_DEPTH)) {
if (child_node->child) {
/* There is at least one child of this node, visit it */
level++;
parent_node = child_node;
child_node =
acpi_ns_get_next_node(parent_node, NULL);
continue;
}
}
/* No more children, re-visit this node */
if (!node_previously_visited) {
node_previously_visited = TRUE;
continue;
}
/* No more children, visit peers */
child_node = acpi_ns_get_next_node(parent_node, child_node);
if (child_node) {
node_previously_visited = FALSE;
}
/* No peers, re-visit parent */
else {
/*
* No more children of this node (acpi_ns_get_next_node failed), go
* back upwards in the namespace tree to the node's parent.
*/
level--;
child_node = parent_node;
parent_node = acpi_ns_get_parent_node(parent_node);
node_previously_visited = TRUE;
}
}
/* Complete walk, not terminated by user function */
return_ACPI_STATUS(AE_OK);
}