/*******************************************************************************
*
* Module Name: nssearch - Namespace search
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2018, 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.h"
#include "accommon.h"
#include "acnamesp.h"
#ifdef ACPI_ASL_COMPILER
#include "amlcode.h"
#endif
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME ("nssearch")
/* Local prototypes */
static ACPI_STATUS
AcpiNsSearchParentTree (
UINT32 TargetName,
ACPI_NAMESPACE_NODE *Node,
ACPI_OBJECT_TYPE Type,
ACPI_NAMESPACE_NODE **ReturnNode);
/*******************************************************************************
*
* FUNCTION: AcpiNsSearchOneScope
*
* PARAMETERS: TargetName - Ascii ACPI name to search for
* ParentNode - Starting node where search will begin
* Type - Object type to match
* ReturnNode - Where the matched Named obj is returned
*
* RETURN: Status
*
* DESCRIPTION: Search a single level of the namespace. Performs a
* simple search of the specified level, and does not add
* entries or search parents.
*
*
* Named object lists are built (and subsequently dumped) in the
* order in which the names are encountered during the namespace load;
*
* All namespace searching is linear in this implementation, but
* could be easily modified to support any improved search
* algorithm. However, the linear search was chosen for simplicity
* and because the trees are small and the other interpreter
* execution overhead is relatively high.
*
* Note: CPU execution analysis has shown that the AML interpreter spends
* a very small percentage of its time searching the namespace. Therefore,
* the linear search seems to be sufficient, as there would seem to be
* little value in improving the search.
*
******************************************************************************/
ACPI_STATUS
AcpiNsSearchOneScope (
UINT32 TargetName,
ACPI_NAMESPACE_NODE *ParentNode,
ACPI_OBJECT_TYPE Type,
ACPI_NAMESPACE_NODE **ReturnNode)
{
ACPI_NAMESPACE_NODE *Node;
ACPI_FUNCTION_TRACE (NsSearchOneScope);
#ifdef ACPI_DEBUG_OUTPUT
if (ACPI_LV_NAMES & AcpiDbgLevel)
{
char *ScopeName;
ScopeName = AcpiNsGetNormalizedPathname (ParentNode, TRUE);
if (ScopeName)
{
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"Searching %s (%p) For [%4.4s] (%s)\n",
ScopeName, ParentNode, ACPI_CAST_PTR (char, &TargetName),
AcpiUtGetTypeName (Type)));
ACPI_FREE (ScopeName);
}
}
#endif
/*
* Search for name at this namespace level, which is to say that we
* must search for the name among the children of this object
*/
Node = ParentNode->Child;
while (Node)
{
/* Check for match against the name */
if (Node->Name.Integer == TargetName)
{
/* Resolve a control method alias if any */
if (AcpiNsGetType (Node) == ACPI_TYPE_LOCAL_METHOD_ALIAS)
{
Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, Node->Object);
}
/* Found matching entry */
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n",
ACPI_CAST_PTR (char, &TargetName),
AcpiUtGetTypeName (Node->Type),
Node, AcpiUtGetNodeName (ParentNode), ParentNode));
*ReturnNode = Node;
return_ACPI_STATUS (AE_OK);
}
/* Didn't match name, move on to the next peer object */
Node = Node->Peer;
}
/* Searched entire namespace level, not found */
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"Name [%4.4s] (%s) not found in search in scope [%4.4s] "
"%p first child %p\n",
ACPI_CAST_PTR (char, &TargetName), AcpiUtGetTypeName (Type),
AcpiUtGetNodeName (ParentNode), ParentNode, ParentNode->Child));
return_ACPI_STATUS (AE_NOT_FOUND);
}
/*******************************************************************************
*
* FUNCTION: AcpiNsSearchParentTree
*
* PARAMETERS: TargetName - Ascii ACPI name to search for
* Node - Starting node where search will begin
* Type - Object type to match
* ReturnNode - Where the matched Node is returned
*
* RETURN: Status
*
* DESCRIPTION: Called when a name has not been found in the current namespace
* level. Before adding it or giving up, ACPI scope rules require
* searching enclosing scopes in cases identified by AcpiNsLocal().
*
* "A name is located by finding the matching name in the current
* name space, and then in the parent name space. If the parent
* name space does not contain the name, the search continues
* recursively until either the name is found or the name space
* does not have a parent (the root of the name space). This
* indicates that the name is not found" (From ACPI Specification,
* section 5.3)
*
******************************************************************************/
static ACPI_STATUS
AcpiNsSearchParentTree (
UINT32 TargetName,
ACPI_NAMESPACE_NODE *Node,
ACPI_OBJECT_TYPE Type,
ACPI_NAMESPACE_NODE **ReturnNode)
{
ACPI_STATUS Status;
ACPI_NAMESPACE_NODE *ParentNode;
ACPI_FUNCTION_TRACE (NsSearchParentTree);
ParentNode = Node->Parent;
/*
* If there is no parent (i.e., we are at the root) or type is "local",
* we won't be searching the parent tree.
*/
if (!ParentNode)
{
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "[%4.4s] has no parent\n",
ACPI_CAST_PTR (char, &TargetName)));
return_ACPI_STATUS (AE_NOT_FOUND);
}
if (AcpiNsLocal (Type))
{
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"[%4.4s] type [%s] must be local to this scope (no parent search)\n",
ACPI_CAST_PTR (char, &TargetName), AcpiUtGetTypeName (Type)));
return_ACPI_STATUS (AE_NOT_FOUND);
}
/* Search the parent tree */
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"Searching parent [%4.4s] for [%4.4s]\n",
AcpiUtGetNodeName (ParentNode), ACPI_CAST_PTR (char, &TargetName)));
/* Search parents until target is found or we have backed up to the root */
while (ParentNode)
{
/*
* Search parent scope. Use TYPE_ANY because we don't care about the
* object type at this point, we only care about the existence of
* the actual name we are searching for. Typechecking comes later.
*/
Status = AcpiNsSearchOneScope (
TargetName, ParentNode, ACPI_TYPE_ANY, ReturnNode);
if (ACPI_SUCCESS (Status))
{
return_ACPI_STATUS (Status);
}
/* Not found here, go up another level (until we reach the root) */
ParentNode = ParentNode->Parent;
}
/* Not found in parent tree */
return_ACPI_STATUS (AE_NOT_FOUND);
}
/*******************************************************************************
*
* FUNCTION: AcpiNsSearchAndEnter
*
* PARAMETERS: TargetName - Ascii ACPI name to search for (4 chars)
* WalkState - Current state of the walk
* Node - Starting node where search will begin
* InterpreterMode - Add names only in ACPI_MODE_LOAD_PASS_x.
* Otherwise,search only.
* Type - Object type to match
* Flags - Flags describing the search restrictions
* ReturnNode - Where the Node is returned
*
* RETURN: Status
*
* DESCRIPTION: Search for a name segment in a single namespace level,
* optionally adding it if it is not found. If the passed
* Type is not Any and the type previously stored in the
* entry was Any (i.e. unknown), update the stored type.
*
* In ACPI_IMODE_EXECUTE, search only.
* In other modes, search and add if not found.
*
******************************************************************************/
ACPI_STATUS
AcpiNsSearchAndEnter (
UINT32 TargetName,
ACPI_WALK_STATE *WalkState,
ACPI_NAMESPACE_NODE *Node,
ACPI_INTERPRETER_MODE InterpreterMode,
ACPI_OBJECT_TYPE Type,
UINT32 Flags,
ACPI_NAMESPACE_NODE **ReturnNode)
{
ACPI_STATUS Status;
ACPI_NAMESPACE_NODE *NewNode;
ACPI_FUNCTION_TRACE (NsSearchAndEnter);
/* Parameter validation */
if (!Node || !TargetName || !ReturnNode)
{
ACPI_ERROR ((AE_INFO,
"Null parameter: Node %p Name 0x%X ReturnNode %p",
Node, TargetName, ReturnNode));
return_ACPI_STATUS (AE_BAD_PARAMETER);
}
/*
* Name must consist of valid ACPI characters. We will repair the name if
* necessary because we don't want to abort because of this, but we want
* all namespace names to be printable. A warning message is appropriate.
*
* This issue came up because there are in fact machines that exhibit
* this problem, and we want to be able to enable ACPI support for them,
* even though there are a few bad names.
*/
AcpiUtRepairName (ACPI_CAST_PTR (char, &TargetName));
/* Try to find the name in the namespace level specified by the caller */
*ReturnNode = ACPI_ENTRY_NOT_FOUND;
Status = AcpiNsSearchOneScope (TargetName, Node, Type, ReturnNode);
if (Status != AE_NOT_FOUND)
{
/*
* If we found it AND the request specifies that a find is an error,
* return the error
*/
if (Status == AE_OK)
{
/* The node was found in the namespace */
/*
* If the namespace override feature is enabled for this node,
* delete any existing attached sub-object and make the node
* look like a new node that is owned by the override table.
*/
if (Flags & ACPI_NS_OVERRIDE_IF_FOUND)
{
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"Namespace override: %4.4s pass %u type %X Owner %X\n",
ACPI_CAST_PTR(char, &TargetName), InterpreterMode,
(*ReturnNode)->Type, WalkState->OwnerId));
AcpiNsDeleteChildren (*ReturnNode);
if (AcpiGbl_RuntimeNamespaceOverride)
{
AcpiUtRemoveReference ((*ReturnNode)->Object);
(*ReturnNode)->Object = NULL;
(*ReturnNode)->OwnerId = WalkState->OwnerId;
}
else
{
AcpiNsRemoveNode (*ReturnNode);
*ReturnNode = ACPI_ENTRY_NOT_FOUND;
}
}
/* Return an error if we don't expect to find the object */
else if (Flags & ACPI_NS_ERROR_IF_FOUND)
{
Status = AE_ALREADY_EXISTS;
}
}
#ifdef ACPI_ASL_COMPILER
if (*ReturnNode && (*ReturnNode)->Type == ACPI_TYPE_ANY)
{
(*ReturnNode)->Flags |= ANOBJ_IS_EXTERNAL;
}
#endif
/* Either found it or there was an error: finished either way */
return_ACPI_STATUS (Status);
}
/*
* The name was not found. If we are NOT performing the first pass
* (name entry) of loading the namespace, search the parent tree (all the
* way to the root if necessary.) We don't want to perform the parent
* search when the namespace is actually being loaded. We want to perform
* the search when namespace references are being resolved (load pass 2)
* and during the execution phase.
*/
if ((InterpreterMode != ACPI_IMODE_LOAD_PASS1) &&
(Flags & ACPI_NS_SEARCH_PARENT))
{
/*
* Not found at this level - search parent tree according to the
* ACPI specification
*/
Status = AcpiNsSearchParentTree (TargetName, Node, Type, ReturnNode);
if (ACPI_SUCCESS (Status))
{
return_ACPI_STATUS (Status);
}
}
/* In execute mode, just search, never add names. Exit now */
if (InterpreterMode == ACPI_IMODE_EXECUTE)
{
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"%4.4s Not found in %p [Not adding]\n",
ACPI_CAST_PTR (char, &TargetName), Node));
return_ACPI_STATUS (AE_NOT_FOUND);
}
/* Create the new named object */
NewNode = AcpiNsCreateNode (TargetName);
if (!NewNode)
{
return_ACPI_STATUS (AE_NO_MEMORY);
}
#ifdef ACPI_ASL_COMPILER
/* Node is an object defined by an External() statement */
if (Flags & ACPI_NS_EXTERNAL ||
(WalkState && WalkState->Opcode == AML_SCOPE_OP))
{
NewNode->Flags |= ANOBJ_IS_EXTERNAL;
}
#endif
if (Flags & ACPI_NS_TEMPORARY)
{
NewNode->Flags |= ANOBJ_TEMPORARY;
}
/* Install the new object into the parent's list of children */
AcpiNsInstallNode (WalkState, Node, NewNode, Type);
*ReturnNode = NewNode;
return_ACPI_STATUS (AE_OK);
}