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linux/drivers/acpi/namespace/nswalk.c

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/******************************************************************************
*
* Module Name: nswalk - Functions for walking the ACPI namespace
*
*****************************************************************************/
/*
* 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>
#include <acpi/acnamesp.h>
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("nswalk")
/*******************************************************************************
*
* FUNCTION: acpi_ns_get_next_node
*
* PARAMETERS: Type - Type of node to be searched for
* parent_node - Parent node whose children we are
ACPICA 20050408 from Bob Moore Fixed three cases in the interpreter where an "index" argument to an ASL function was still (internally) 32 bits instead of the required 64 bits. This was the Index argument to the Index, Mid, and Match operators. The "strupr" function is now permanently local (acpi_ut_strupr), since this is not a POSIX-defined function and not present in most kernel-level C libraries. References to the C library strupr function have been removed from the headers. Completed the deployment of static functions/prototypes. All prototypes with the static attribute have been moved from the headers to the owning C file. ACPICA 20050329 from Bob Moore An error is now generated if an attempt is made to create a Buffer Field of length zero (A CreateField with a length operand of zero.) The interpreter now issues a warning whenever executable code at the module level is detected during ACPI table load. This will give some idea of the prevalence of this type of code. Implemented support for references to named objects (other than control methods) within package objects. Enhanced package object output for the debug object. Package objects are now completely dumped, showing all elements. Enhanced miscellaneous object output for the debug object. Any object can now be written to the debug object (for example, a device object can be written, and the type of the object will be displayed.) The "static" qualifier has been added to all local functions across the core subsystem. The number of "long" lines (> 80 chars) within the source has been significantly reduced, by about 1/3. Cleaned up all header files to ensure that all CA/iASL functions are prototyped (even static functions) and the formatting is consistent. Two new header files have been added, acopcode.h and acnames.h. Removed several obsolete functions that were no longer used. Signed-off-by: Len Brown <len.brown@intel.com>
2005-04-18 19:49:35 -07:00
* 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(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();
if (!child_node) {
/* It's really the parent's _scope_ that we want */
if (parent_node->child) {
next_node = parent_node->child;
}
}
else {
/* Start search at the NEXT node */
next_node = acpi_ns_get_next_valid_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
* user_function - Called when an object of "Type" is found
* Context - Passed to user function
* 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 user_function is called whenever a node that matches
* the type parameter is found. If the user 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 User Function 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 user_function,
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;
ACPI: ACPICA 20060421 Removed a device initialization optimization introduced in 20051216 where the _STA method was not run unless an _INI was also present for the same device. This optimization could cause problems because it could allow _INI methods to be run within a not-present device subtree (If a not-present device had no _INI, _STA would not be run, the not-present status would not be discovered, and the children of the device would be incorrectly traversed.) Implemented a new _STA optimization where namespace subtrees that do not contain _INI are identified and ignored during device initialization. Selectively running _STA can significantly improve boot time on large machines (with assistance from Len Brown.) Implemented support for the device initialization case where the returned _STA flags indicate a device not-present but functioning. In this case, _INI is not run, but the device children are examined for presence, as per the ACPI specification. Implemented an additional change to the IndexField support in order to conform to MS behavior. The value written to the Index Register is not simply a byte offset, it is a byte offset in units of the access width of the parent Index Field. (Fiodor Suietov) Defined and deployed a new OSL interface, acpi_os_validate_address(). This interface is called during the creation of all AML operation regions, and allows the host OS to exert control over what addresses it will allow the AML code to access. Operation Regions whose addresses are disallowed will cause a runtime exception when they are actually accessed (will not affect or abort table loading.) Defined and deployed a new OSL interface, acpi_os_validate_interface(). This interface allows the host OS to match the various "optional" interface/behavior strings for the _OSI predefined control method as appropriate (with assistance from Bjorn Helgaas.) Restructured and corrected various problems in the exception handling code paths within DsCallControlMethod and DsTerminateControlMethod in dsmethod (with assistance from Takayoshi Kochi.) Modified the Linux source converter to ignore quoted string literals while converting identifiers from mixed to lower case. This will correct problems with the disassembler and other areas where such strings must not be modified. The ACPI_FUNCTION_* macros no longer require quotes around the function name. This allows the Linux source converter to convert the names, now that the converter ignores quoted strings. Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-04-21 14:15:00 -07:00
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 = 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) {
/* Get the next node in this scope. Null if not found */
status = AE_OK;
child_node =
acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node,
child_node);
if (child_node) {
/* 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);
}
}
status =
user_function(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 ((level < max_depth) && (status != AE_CTRL_DEPTH)) {
if (acpi_ns_get_next_node
(ACPI_TYPE_ANY, child_node, NULL)) {
/* There is at least one child of this node, visit it */
level++;
parent_node = child_node;
child_node = NULL;
}
}
} 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);
}
}
/* Complete walk, not terminated by user function */
return_ACPI_STATUS(AE_OK);
}