/*******************************************************************************
*
* Module Name: nsaccess - Top-level functions for accessing ACPI namespace
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2012, 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 "amlcode.h"
#include "acnamesp.h"
#include "acdispat.h"
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("nsaccess")
/*******************************************************************************
*
* FUNCTION: acpi_ns_root_initialize
*
* PARAMETERS: None
*
* RETURN: Status
*
* DESCRIPTION: Allocate and initialize the default root named objects
*
* MUTEX: Locks namespace for entire execution
*
******************************************************************************/
acpi_status acpi_ns_root_initialize(void)
{
acpi_status status;
const struct acpi_predefined_names *init_val = NULL;
struct acpi_namespace_node *new_node;
union acpi_operand_object *obj_desc;
acpi_string val = NULL;
ACPI_FUNCTION_TRACE(ns_root_initialize);
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* The global root ptr is initially NULL, so a non-NULL value indicates
* that acpi_ns_root_initialize() has already been called; just return.
*/
if (acpi_gbl_root_node) {
status = AE_OK;
goto unlock_and_exit;
}
/*
* Tell the rest of the subsystem that the root is initialized
* (This is OK because the namespace is locked)
*/
acpi_gbl_root_node = &acpi_gbl_root_node_struct;
/* Enter the pre-defined names in the name table */
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Entering predefined entries into namespace\n"));
for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) {
/* _OSI is optional for now, will be permanent later */
if (!ACPI_STRCMP(init_val->name, "_OSI")
&& !acpi_gbl_create_osi_method) {
continue;
}
status = acpi_ns_lookup(NULL, init_val->name, init_val->type,
ACPI_IMODE_LOAD_PASS2,
ACPI_NS_NO_UPSEARCH, NULL, &new_node);
if (ACPI_FAILURE(status) || (!new_node)) { /* Must be on same line for code converter */
ACPI_EXCEPTION((AE_INFO, status,
"Could not create predefined name %s",
init_val->name));
}
/*
* Name entered successfully. If entry in pre_defined_names[] specifies
* an initial value, create the initial value.
*/
if (init_val->val) {
status = acpi_os_predefined_override(init_val, &val);
if (ACPI_FAILURE(status)) {
ACPI_ERROR((AE_INFO,
"Could not override predefined %s",
init_val->name));
}
if (!val) {
val = init_val->val;
}
/*
* Entry requests an initial value, allocate a
* descriptor for it.
*/
obj_desc =
acpi_ut_create_internal_object(init_val->type);
if (!obj_desc) {
status = AE_NO_MEMORY;
goto unlock_and_exit;
}
/*
* Convert value string from table entry to
* internal representation. Only types actually
* used for initial values are implemented here.
*/
switch (init_val->type) {
case ACPI_TYPE_METHOD:
obj_desc->method.param_count =
(u8) ACPI_TO_INTEGER(val);
obj_desc->common.flags |= AOPOBJ_DATA_VALID;
#if defined (ACPI_ASL_COMPILER)
/* Save the parameter count for the i_aSL compiler */
new_node->value = obj_desc->method.param_count;
#else
/* Mark this as a very SPECIAL method */
obj_desc->method.info_flags =
ACPI_METHOD_INTERNAL_ONLY;
obj_desc->method.dispatch.implementation =
acpi_ut_osi_implementation;
#endif
break;
case ACPI_TYPE_INTEGER:
obj_desc->integer.value = ACPI_TO_INTEGER(val);
break;
case ACPI_TYPE_STRING:
/* Build an object around the static string */
obj_desc->string.length =
(u32) ACPI_STRLEN(val);
obj_desc->string.pointer = val;
obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
break;
case ACPI_TYPE_MUTEX:
obj_desc->mutex.node = new_node;
obj_desc->mutex.sync_level =
(u8) (ACPI_TO_INTEGER(val) - 1);
/* Create a mutex */
status =
acpi_os_create_mutex(&obj_desc->mutex.
os_mutex);
if (ACPI_FAILURE(status)) {
acpi_ut_remove_reference(obj_desc);
goto unlock_and_exit;
}
/* Special case for ACPI Global Lock */
if (ACPI_STRCMP(init_val->name, "_GL_") == 0) {
acpi_gbl_global_lock_mutex = obj_desc;
/* Create additional counting semaphore for global lock */
status =
acpi_os_create_semaphore(1, 0,
&acpi_gbl_global_lock_semaphore);
if (ACPI_FAILURE(status)) {
acpi_ut_remove_reference
(obj_desc);
goto unlock_and_exit;
}
}
break;
default:
ACPI_ERROR((AE_INFO,
"Unsupported initial type value 0x%X",
init_val->type));
acpi_ut_remove_reference(obj_desc);
obj_desc = NULL;
continue;
}
/* Store pointer to value descriptor in the Node */
status = acpi_ns_attach_object(new_node, obj_desc,
obj_desc->common.type);
/* Remove local reference to the object */
acpi_ut_remove_reference(obj_desc);
}
}
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
/* Save a handle to "_GPE", it is always present */
if (ACPI_SUCCESS(status)) {
status = acpi_ns_get_node(NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
&acpi_gbl_fadt_gpe_device);
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_lookup
*
* PARAMETERS: scope_info - Current scope info block
* Pathname - Search pathname, in internal format
* (as represented in the AML stream)
* Type - Type associated with name
* interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
* Flags - Flags describing the search restrictions
* walk_state - Current state of the walk
* return_node - Where the Node is placed (if found
* or created successfully)
*
* RETURN: Status
*
* DESCRIPTION: Find or enter the passed name in the name space.
* Log an error if name not found in Exec mode.
*
* MUTEX: Assumes namespace is locked.
*
******************************************************************************/
acpi_status
acpi_ns_lookup(union acpi_generic_state *scope_info,
char *pathname,
acpi_object_type type,
acpi_interpreter_mode interpreter_mode,
u32 flags,
struct acpi_walk_state *walk_state,
struct acpi_namespace_node **return_node)
{
acpi_status status;
char *path = pathname;
struct acpi_namespace_node *prefix_node;
struct acpi_namespace_node *current_node = NULL;
struct acpi_namespace_node *this_node = NULL;
u32 num_segments;
u32 num_carats;
acpi_name simple_name;
acpi_object_type type_to_check_for;
acpi_object_type this_search_type;
u32 search_parent_flag = ACPI_NS_SEARCH_PARENT;
u32 local_flags;
ACPI_FUNCTION_TRACE(ns_lookup);
if (!return_node) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
local_flags = flags & ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_SEARCH_PARENT);
*return_node = ACPI_ENTRY_NOT_FOUND;
acpi_gbl_ns_lookup_count++;
if (!acpi_gbl_root_node) {
return_ACPI_STATUS(AE_NO_NAMESPACE);
}
/* Get the prefix scope. A null scope means use the root scope */
if ((!scope_info) || (!scope_info->scope.node)) {
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Null scope prefix, using root node (%p)\n",
acpi_gbl_root_node));
prefix_node = acpi_gbl_root_node;
} else {
prefix_node = scope_info->scope.node;
if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) !=
ACPI_DESC_TYPE_NAMED) {
ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]",
prefix_node,
acpi_ut_get_descriptor_name(prefix_node)));
return_ACPI_STATUS(AE_AML_INTERNAL);
}
if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) {
/*
* This node might not be a actual "scope" node (such as a
* Device/Method, etc.) It could be a Package or other object
* node. Backup up the tree to find the containing scope node.
*/
while (!acpi_ns_opens_scope(prefix_node->type) &&
prefix_node->type != ACPI_TYPE_ANY) {
prefix_node = prefix_node->parent;
}
}
}
/* Save type. TBD: may be no longer necessary */
type_to_check_for = type;
/*
* Begin examination of the actual pathname
*/
if (!pathname) {
/* A Null name_path is allowed and refers to the root */
num_segments = 0;
this_node = acpi_gbl_root_node;
path = "";
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Null Pathname (Zero segments), Flags=%X\n",
flags));
} else {
/*
* Name pointer is valid (and must be in internal name format)
*
* Check for scope prefixes:
*
* As represented in the AML stream, a namepath consists of an
* optional scope prefix followed by a name segment part.
*
* If present, the scope prefix is either a Root Prefix (in
* which case the name is fully qualified), or one or more
* Parent Prefixes (in which case the name's scope is relative
* to the current scope).
*/
if (*path == (u8) AML_ROOT_PREFIX) {
/* Pathname is fully qualified, start from the root */
this_node = acpi_gbl_root_node;
search_parent_flag = ACPI_NS_NO_UPSEARCH;
/* Point to name segment part */
path++;
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Path is absolute from root [%p]\n",
this_node));
} else {
/* Pathname is relative to current scope, start there */
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Searching relative to prefix scope [%4.4s] (%p)\n",
acpi_ut_get_node_name(prefix_node),
prefix_node));
/*
* Handle multiple Parent Prefixes (carat) by just getting
* the parent node for each prefix instance.
*/
this_node = prefix_node;
num_carats = 0;
while (*path == (u8) AML_PARENT_PREFIX) {
/* Name is fully qualified, no search rules apply */
search_parent_flag = ACPI_NS_NO_UPSEARCH;
/*
* Point past this prefix to the name segment
* part or the next Parent Prefix
*/
path++;
/* Backup to the parent node */
num_carats++;
this_node = this_node->parent;
if (!this_node) {
/* Current scope has no parent scope */
ACPI_ERROR((AE_INFO,
"ACPI path has too many parent prefixes (^) "
"- reached beyond root node"));
return_ACPI_STATUS(AE_NOT_FOUND);
}
}
if (search_parent_flag == ACPI_NS_NO_UPSEARCH) {
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Search scope is [%4.4s], path has %u carat(s)\n",
acpi_ut_get_node_name
(this_node), num_carats));
}
}
/*
* Determine the number of ACPI name segments in this pathname.
*
* The segment part consists of either:
* - A Null name segment (0)
* - A dual_name_prefix followed by two 4-byte name segments
* - A multi_name_prefix followed by a byte indicating the
* number of segments and the segments themselves.
* - A single 4-byte name segment
*
* Examine the name prefix opcode, if any, to determine the number of
* segments.
*/
switch (*path) {
case 0:
/*
* Null name after a root or parent prefixes. We already
* have the correct target node and there are no name segments.
*/
num_segments = 0;
type = this_node->type;
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Prefix-only Pathname (Zero name segments), Flags=%X\n",
flags));
break;
case AML_DUAL_NAME_PREFIX:
/* More than one name_seg, search rules do not apply */
search_parent_flag = ACPI_NS_NO_UPSEARCH;
/* Two segments, point to first name segment */
num_segments = 2;
path++;
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Dual Pathname (2 segments, Flags=%X)\n",
flags));
break;
case AML_MULTI_NAME_PREFIX_OP:
/* More than one name_seg, search rules do not apply */
search_parent_flag = ACPI_NS_NO_UPSEARCH;
/* Extract segment count, point to first name segment */
path++;
num_segments = (u32) (u8) * path;
path++;
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Multi Pathname (%u Segments, Flags=%X)\n",
num_segments, flags));
break;
default:
/*
* Not a Null name, no Dual or Multi prefix, hence there is
* only one name segment and Pathname is already pointing to it.
*/
num_segments = 1;
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Simple Pathname (1 segment, Flags=%X)\n",
flags));
break;
}
ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path));
}
/*
* Search namespace for each segment of the name. Loop through and
* verify (or add to the namespace) each name segment.
*
* The object type is significant only at the last name
* segment. (We don't care about the types along the path, only
* the type of the final target object.)
*/
this_search_type = ACPI_TYPE_ANY;
current_node = this_node;
while (num_segments && current_node) {
num_segments--;
if (!num_segments) {
/* This is the last segment, enable typechecking */
this_search_type = type;
/*
* Only allow automatic parent search (search rules) if the caller
* requested it AND we have a single, non-fully-qualified name_seg
*/
if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) &&
(flags & ACPI_NS_SEARCH_PARENT)) {
local_flags |= ACPI_NS_SEARCH_PARENT;
}
/* Set error flag according to caller */
if (flags & ACPI_NS_ERROR_IF_FOUND) {
local_flags |= ACPI_NS_ERROR_IF_FOUND;
}
}
/* Extract one ACPI name from the front of the pathname */
ACPI_MOVE_32_TO_32(&simple_name, path);
/* Try to find the single (4 character) ACPI name */
status =
acpi_ns_search_and_enter(simple_name, walk_state,
current_node, interpreter_mode,
this_search_type, local_flags,
&this_node);
if (ACPI_FAILURE(status)) {
if (status == AE_NOT_FOUND) {
/* Name not found in ACPI namespace */
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Name [%4.4s] not found in scope [%4.4s] %p\n",
(char *)&simple_name,
(char *)¤t_node->name,
current_node));
}
*return_node = this_node;
return_ACPI_STATUS(status);
}
/* More segments to follow? */
if (num_segments > 0) {
/*
* If we have an alias to an object that opens a scope (such as a
* device or processor), we need to dereference the alias here so
* that we can access any children of the original node (via the
* remaining segments).
*/
if (this_node->type == ACPI_TYPE_LOCAL_ALIAS) {
if (!this_node->object) {
return_ACPI_STATUS(AE_NOT_EXIST);
}
if (acpi_ns_opens_scope
(((struct acpi_namespace_node *)
this_node->object)->type)) {
this_node =
(struct acpi_namespace_node *)
this_node->object;
}
}
}
/* Special handling for the last segment (num_segments == 0) */
else {
/*
* Sanity typecheck of the target object:
*
* If 1) This is the last segment (num_segments == 0)
* 2) And we are looking for a specific type
* (Not checking for TYPE_ANY)
* 3) Which is not an alias
* 4) Which is not a local type (TYPE_SCOPE)
* 5) And the type of target object is known (not TYPE_ANY)
* 6) And target object does not match what we are looking for
*
* Then we have a type mismatch. Just warn and ignore it.
*/
if ((type_to_check_for != ACPI_TYPE_ANY) &&
(type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
(type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS)
&& (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE)
&& (this_node->type != ACPI_TYPE_ANY)
&& (this_node->type != type_to_check_for)) {
/* Complain about a type mismatch */
ACPI_WARNING((AE_INFO,
"NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
ACPI_CAST_PTR(char, &simple_name),
acpi_ut_get_type_name(this_node->
type),
acpi_ut_get_type_name
(type_to_check_for)));
}
/*
* If this is the last name segment and we are not looking for a
* specific type, but the type of found object is known, use that
* type to (later) see if it opens a scope.
*/
if (type == ACPI_TYPE_ANY) {
type = this_node->type;
}
}
/* Point to next name segment and make this node current */
path += ACPI_NAME_SIZE;
current_node = this_node;
}
/* Always check if we need to open a new scope */
if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) {
/*
* If entry is a type which opens a scope, push the new scope on the
* scope stack.
*/
if (acpi_ns_opens_scope(type)) {
status =
acpi_ds_scope_stack_push(this_node, type,
walk_state);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
}
*return_node = this_node;
return_ACPI_STATUS(AE_OK);
}