1
/*******************************************************************************
3
* Module Name: nsaccess - Top-level functions for accessing ACPI namespace
5
******************************************************************************/
8
* Copyright (C) 2000 - 2011, Intel Corp.
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions, and the following disclaimer,
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* without modification.
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* 2. Redistributions in binary form must reproduce at minimum a disclaimer
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* substantially similar to the "NO WARRANTY" disclaimer below
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* ("Disclaimer") and any redistribution must be conditioned upon
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* including a substantially similar Disclaimer requirement for further
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* binary redistribution.
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* 3. Neither the names of the above-listed copyright holders nor the names
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* of any contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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* Alternatively, this software may be distributed under the terms of the
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* GNU General Public License ("GPL") version 2 as published by the Free
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* Software Foundation.
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGES.
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#include <acpi/acpi.h>
50
#define _COMPONENT ACPI_NAMESPACE
51
ACPI_MODULE_NAME("nsaccess")
53
/*******************************************************************************
55
* FUNCTION: acpi_ns_root_initialize
61
* DESCRIPTION: Allocate and initialize the default root named objects
63
* MUTEX: Locks namespace for entire execution
65
******************************************************************************/
66
acpi_status acpi_ns_root_initialize(void)
69
const struct acpi_predefined_names *init_val = NULL;
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struct acpi_namespace_node *new_node;
71
union acpi_operand_object *obj_desc;
72
acpi_string val = NULL;
74
ACPI_FUNCTION_TRACE(ns_root_initialize);
76
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
77
if (ACPI_FAILURE(status)) {
78
return_ACPI_STATUS(status);
82
* The global root ptr is initially NULL, so a non-NULL value indicates
83
* that acpi_ns_root_initialize() has already been called; just return.
85
if (acpi_gbl_root_node) {
91
* Tell the rest of the subsystem that the root is initialized
92
* (This is OK because the namespace is locked)
94
acpi_gbl_root_node = &acpi_gbl_root_node_struct;
96
/* Enter the pre-defined names in the name table */
98
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
99
"Entering predefined entries into namespace\n"));
101
for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) {
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/* _OSI is optional for now, will be permanent later */
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if (!ACPI_STRCMP(init_val->name, "_OSI")
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&& !acpi_gbl_create_osi_method) {
110
status = acpi_ns_lookup(NULL, init_val->name, init_val->type,
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ACPI_IMODE_LOAD_PASS2,
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ACPI_NS_NO_UPSEARCH, NULL, &new_node);
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if (ACPI_FAILURE(status) || (!new_node)) { /* Must be on same line for code converter */
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ACPI_EXCEPTION((AE_INFO, status,
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"Could not create predefined name %s",
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* Name entered successfully. If entry in pre_defined_names[] specifies
122
* an initial value, create the initial value.
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status = acpi_os_predefined_override(init_val, &val);
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if (ACPI_FAILURE(status)) {
128
"Could not override predefined %s",
137
* Entry requests an initial value, allocate a
141
acpi_ut_create_internal_object(init_val->type);
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status = AE_NO_MEMORY;
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goto unlock_and_exit;
148
* Convert value string from table entry to
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* internal representation. Only types actually
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* used for initial values are implemented here.
152
switch (init_val->type) {
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case ACPI_TYPE_METHOD:
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obj_desc->method.param_count =
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(u8) ACPI_TO_INTEGER(val);
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obj_desc->common.flags |= AOPOBJ_DATA_VALID;
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#if defined (ACPI_ASL_COMPILER)
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/* Save the parameter count for the i_aSL compiler */
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new_node->value = obj_desc->method.param_count;
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/* Mark this as a very SPECIAL method */
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obj_desc->method.info_flags =
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ACPI_METHOD_INTERNAL_ONLY;
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obj_desc->method.dispatch.implementation =
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acpi_ut_osi_implementation;
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case ACPI_TYPE_INTEGER:
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obj_desc->integer.value = ACPI_TO_INTEGER(val);
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case ACPI_TYPE_STRING:
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/* Build an object around the static string */
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obj_desc->string.length =
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(u32) ACPI_STRLEN(val);
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obj_desc->string.pointer = val;
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obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
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case ACPI_TYPE_MUTEX:
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obj_desc->mutex.node = new_node;
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obj_desc->mutex.sync_level =
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(u8) (ACPI_TO_INTEGER(val) - 1);
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acpi_os_create_mutex(&obj_desc->mutex.
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if (ACPI_FAILURE(status)) {
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acpi_ut_remove_reference(obj_desc);
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goto unlock_and_exit;
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/* Special case for ACPI Global Lock */
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if (ACPI_STRCMP(init_val->name, "_GL_") == 0) {
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acpi_gbl_global_lock_mutex = obj_desc;
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/* Create additional counting semaphore for global lock */
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acpi_os_create_semaphore(1, 0,
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&acpi_gbl_global_lock_semaphore);
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if (ACPI_FAILURE(status)) {
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acpi_ut_remove_reference
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goto unlock_and_exit;
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"Unsupported initial type value 0x%X",
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acpi_ut_remove_reference(obj_desc);
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/* Store pointer to value descriptor in the Node */
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status = acpi_ns_attach_object(new_node, obj_desc,
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obj_desc->common.type);
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/* Remove local reference to the object */
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acpi_ut_remove_reference(obj_desc);
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(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
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/* Save a handle to "_GPE", it is always present */
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if (ACPI_SUCCESS(status)) {
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status = acpi_ns_get_node(NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
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&acpi_gbl_fadt_gpe_device);
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return_ACPI_STATUS(status);
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/*******************************************************************************
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* FUNCTION: acpi_ns_lookup
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* PARAMETERS: scope_info - Current scope info block
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* Pathname - Search pathname, in internal format
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* (as represented in the AML stream)
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* Type - Type associated with name
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* interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
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* Flags - Flags describing the search restrictions
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* walk_state - Current state of the walk
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* return_node - Where the Node is placed (if found
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* or created successfully)
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* DESCRIPTION: Find or enter the passed name in the name space.
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* Log an error if name not found in Exec mode.
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* MUTEX: Assumes namespace is locked.
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******************************************************************************/
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acpi_ns_lookup(union acpi_generic_state *scope_info,
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acpi_object_type type,
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acpi_interpreter_mode interpreter_mode,
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struct acpi_walk_state *walk_state,
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struct acpi_namespace_node **return_node)
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char *path = pathname;
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struct acpi_namespace_node *prefix_node;
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struct acpi_namespace_node *current_node = NULL;
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struct acpi_namespace_node *this_node = NULL;
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acpi_name simple_name;
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acpi_object_type type_to_check_for;
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acpi_object_type this_search_type;
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u32 search_parent_flag = ACPI_NS_SEARCH_PARENT;
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ACPI_FUNCTION_TRACE(ns_lookup);
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return_ACPI_STATUS(AE_BAD_PARAMETER);
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local_flags = flags & ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_SEARCH_PARENT);
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*return_node = ACPI_ENTRY_NOT_FOUND;
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acpi_gbl_ns_lookup_count++;
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if (!acpi_gbl_root_node) {
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return_ACPI_STATUS(AE_NO_NAMESPACE);
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/* Get the prefix scope. A null scope means use the root scope */
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if ((!scope_info) || (!scope_info->scope.node)) {
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ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
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"Null scope prefix, using root node (%p)\n",
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acpi_gbl_root_node));
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prefix_node = acpi_gbl_root_node;
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prefix_node = scope_info->scope.node;
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if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) !=
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ACPI_DESC_TYPE_NAMED) {
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ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]",
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acpi_ut_get_descriptor_name(prefix_node)));
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return_ACPI_STATUS(AE_AML_INTERNAL);
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if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) {
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* This node might not be a actual "scope" node (such as a
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* Device/Method, etc.) It could be a Package or other object
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* node. Backup up the tree to find the containing scope node.
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while (!acpi_ns_opens_scope(prefix_node->type) &&
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prefix_node->type != ACPI_TYPE_ANY) {
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prefix_node = prefix_node->parent;
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/* Save type. TBD: may be no longer necessary */
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type_to_check_for = type;
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* Begin examination of the actual pathname
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/* A Null name_path is allowed and refers to the root */
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this_node = acpi_gbl_root_node;
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ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
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"Null Pathname (Zero segments), Flags=%X\n",
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* Name pointer is valid (and must be in internal name format)
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* Check for scope prefixes:
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* As represented in the AML stream, a namepath consists of an
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* optional scope prefix followed by a name segment part.
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* If present, the scope prefix is either a Root Prefix (in
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* which case the name is fully qualified), or one or more
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* Parent Prefixes (in which case the name's scope is relative
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* to the current scope).
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if (*path == (u8) AML_ROOT_PREFIX) {
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/* Pathname is fully qualified, start from the root */
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this_node = acpi_gbl_root_node;
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search_parent_flag = ACPI_NS_NO_UPSEARCH;
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/* Point to name segment part */
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ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
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"Path is absolute from root [%p]\n",
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/* Pathname is relative to current scope, start there */
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ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
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"Searching relative to prefix scope [%4.4s] (%p)\n",
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acpi_ut_get_node_name(prefix_node),
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* Handle multiple Parent Prefixes (carat) by just getting
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* the parent node for each prefix instance.
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this_node = prefix_node;
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while (*path == (u8) AML_PARENT_PREFIX) {
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/* Name is fully qualified, no search rules apply */
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search_parent_flag = ACPI_NS_NO_UPSEARCH;
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* Point past this prefix to the name segment
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* part or the next Parent Prefix
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/* Backup to the parent node */
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this_node = this_node->parent;
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/* Current scope has no parent scope */
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"ACPI path has too many parent prefixes (^) "
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"- reached beyond root node"));
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return_ACPI_STATUS(AE_NOT_FOUND);
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if (search_parent_flag == ACPI_NS_NO_UPSEARCH) {
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ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
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"Search scope is [%4.4s], path has %u carat(s)\n",
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acpi_ut_get_node_name
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(this_node), num_carats));
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* Determine the number of ACPI name segments in this pathname.
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* The segment part consists of either:
445
* - A Null name segment (0)
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* - A dual_name_prefix followed by two 4-byte name segments
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* - A multi_name_prefix followed by a byte indicating the
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* number of segments and the segments themselves.
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* - A single 4-byte name segment
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* Examine the name prefix opcode, if any, to determine the number of
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* Null name after a root or parent prefixes. We already
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* have the correct target node and there are no name segments.
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type = this_node->type;
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ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
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"Prefix-only Pathname (Zero name segments), Flags=%X\n",
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case AML_DUAL_NAME_PREFIX:
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/* More than one name_seg, search rules do not apply */
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search_parent_flag = ACPI_NS_NO_UPSEARCH;
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/* Two segments, point to first name segment */
479
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
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"Dual Pathname (2 segments, Flags=%X)\n",
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case AML_MULTI_NAME_PREFIX_OP:
486
/* More than one name_seg, search rules do not apply */
488
search_parent_flag = ACPI_NS_NO_UPSEARCH;
490
/* Extract segment count, point to first name segment */
493
num_segments = (u32) (u8) * path;
496
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
497
"Multi Pathname (%u Segments, Flags=%X)\n",
498
num_segments, flags));
503
* Not a Null name, no Dual or Multi prefix, hence there is
504
* only one name segment and Pathname is already pointing to it.
508
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
509
"Simple Pathname (1 segment, Flags=%X)\n",
514
ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path));
518
* Search namespace for each segment of the name. Loop through and
519
* verify (or add to the namespace) each name segment.
521
* The object type is significant only at the last name
522
* segment. (We don't care about the types along the path, only
523
* the type of the final target object.)
525
this_search_type = ACPI_TYPE_ANY;
526
current_node = this_node;
527
while (num_segments && current_node) {
531
/* This is the last segment, enable typechecking */
533
this_search_type = type;
536
* Only allow automatic parent search (search rules) if the caller
537
* requested it AND we have a single, non-fully-qualified name_seg
539
if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) &&
540
(flags & ACPI_NS_SEARCH_PARENT)) {
541
local_flags |= ACPI_NS_SEARCH_PARENT;
544
/* Set error flag according to caller */
546
if (flags & ACPI_NS_ERROR_IF_FOUND) {
547
local_flags |= ACPI_NS_ERROR_IF_FOUND;
551
/* Extract one ACPI name from the front of the pathname */
553
ACPI_MOVE_32_TO_32(&simple_name, path);
555
/* Try to find the single (4 character) ACPI name */
558
acpi_ns_search_and_enter(simple_name, walk_state,
559
current_node, interpreter_mode,
560
this_search_type, local_flags,
562
if (ACPI_FAILURE(status)) {
563
if (status == AE_NOT_FOUND) {
565
/* Name not found in ACPI namespace */
567
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
568
"Name [%4.4s] not found in scope [%4.4s] %p\n",
569
(char *)&simple_name,
570
(char *)¤t_node->name,
574
*return_node = this_node;
575
return_ACPI_STATUS(status);
578
/* More segments to follow? */
580
if (num_segments > 0) {
582
* If we have an alias to an object that opens a scope (such as a
583
* device or processor), we need to dereference the alias here so
584
* that we can access any children of the original node (via the
585
* remaining segments).
587
if (this_node->type == ACPI_TYPE_LOCAL_ALIAS) {
588
if (!this_node->object) {
589
return_ACPI_STATUS(AE_NOT_EXIST);
592
if (acpi_ns_opens_scope
593
(((struct acpi_namespace_node *)
594
this_node->object)->type)) {
596
(struct acpi_namespace_node *)
602
/* Special handling for the last segment (num_segments == 0) */
606
* Sanity typecheck of the target object:
608
* If 1) This is the last segment (num_segments == 0)
609
* 2) And we are looking for a specific type
610
* (Not checking for TYPE_ANY)
611
* 3) Which is not an alias
612
* 4) Which is not a local type (TYPE_SCOPE)
613
* 5) And the type of target object is known (not TYPE_ANY)
614
* 6) And target object does not match what we are looking for
616
* Then we have a type mismatch. Just warn and ignore it.
618
if ((type_to_check_for != ACPI_TYPE_ANY) &&
619
(type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
620
(type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS)
621
&& (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE)
622
&& (this_node->type != ACPI_TYPE_ANY)
623
&& (this_node->type != type_to_check_for)) {
625
/* Complain about a type mismatch */
627
ACPI_WARNING((AE_INFO,
628
"NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
629
ACPI_CAST_PTR(char, &simple_name),
630
acpi_ut_get_type_name(this_node->
632
acpi_ut_get_type_name
633
(type_to_check_for)));
637
* If this is the last name segment and we are not looking for a
638
* specific type, but the type of found object is known, use that
639
* type to (later) see if it opens a scope.
641
if (type == ACPI_TYPE_ANY) {
642
type = this_node->type;
646
/* Point to next name segment and make this node current */
648
path += ACPI_NAME_SIZE;
649
current_node = this_node;
652
/* Always check if we need to open a new scope */
654
if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) {
656
* If entry is a type which opens a scope, push the new scope on the
659
if (acpi_ns_opens_scope(type)) {
661
acpi_ds_scope_stack_push(this_node, type,
663
if (ACPI_FAILURE(status)) {
664
return_ACPI_STATUS(status);
669
*return_node = this_node;
670
return_ACPI_STATUS(AE_OK);