linux/drivers/acpi/namespace/nswalk.c
Bob Moore b229cf92ee 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>
2006-06-14 02:30:55 -04:00

288 lines
8.7 KiB
C

/******************************************************************************
*
* Module Name: nswalk - Functions for walking the ACPI namespace
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2006, 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
* 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
* unlock_before_callback- 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,
u8 unlock_before_callback,
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_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 node, Get the type if we are not
* searching for ANY
*/
if (type != ACPI_TYPE_ANY) {
child_type = child_node->type;
}
if (child_type == type) {
/*
* Found a matching node, invoke the user
* callback function
*/
if (unlock_before_callback) {
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 (unlock_before_callback) {
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 the onde
*/
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);
}