| /****************************************************************************** |
| * |
| * Module Name: nswalk - Functions for walking the ACPI namespace |
| * |
| *****************************************************************************/ |
| |
| /* |
| * Copyright (C) 2000 - 2016, 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" |
| |
| |
| #define _COMPONENT ACPI_NAMESPACE |
| ACPI_MODULE_NAME ("nswalk") |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiNsGetNextNode |
| * |
| * PARAMETERS: ParentNode - Parent node whose children we are |
| * getting |
| * ChildNode - Previous child that was found. |
| * The NEXT child will be returned |
| * |
| * RETURN: 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. |
| * |
| ******************************************************************************/ |
| |
| ACPI_NAMESPACE_NODE * |
| AcpiNsGetNextNode ( |
| ACPI_NAMESPACE_NODE *ParentNode, |
| ACPI_NAMESPACE_NODE *ChildNode) |
| { |
| ACPI_FUNCTION_ENTRY (); |
| |
| |
| if (!ChildNode) |
| { |
| /* It's really the parent's _scope_ that we want */ |
| |
| return (ParentNode->Child); |
| } |
| |
| /* Otherwise just return the next peer */ |
| |
| return (ChildNode->Peer); |
| } |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiNsGetNextNodeTyped |
| * |
| * PARAMETERS: Type - Type of node to be searched for |
| * ParentNode - Parent node whose children we are |
| * getting |
| * ChildNode - Previous child that was found. |
| * The NEXT child will be returned |
| * |
| * RETURN: 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. |
| * |
| ******************************************************************************/ |
| |
| ACPI_NAMESPACE_NODE * |
| AcpiNsGetNextNodeTyped ( |
| ACPI_OBJECT_TYPE Type, |
| ACPI_NAMESPACE_NODE *ParentNode, |
| ACPI_NAMESPACE_NODE *ChildNode) |
| { |
| ACPI_NAMESPACE_NODE *NextNode = NULL; |
| |
| |
| ACPI_FUNCTION_ENTRY (); |
| |
| |
| NextNode = AcpiNsGetNextNode (ParentNode, ChildNode); |
| |
| /* If any type is OK, we are done */ |
| |
| if (Type == ACPI_TYPE_ANY) |
| { |
| /* NextNode is NULL if we are at the end-of-list */ |
| |
| return (NextNode); |
| } |
| |
| /* Must search for the node -- but within this scope only */ |
| |
| while (NextNode) |
| { |
| /* If type matches, we are done */ |
| |
| if (NextNode->Type == Type) |
| { |
| return (NextNode); |
| } |
| |
| /* Otherwise, move on to the next peer node */ |
| |
| NextNode = NextNode->Peer; |
| } |
| |
| /* Not found */ |
| |
| return (NULL); |
| } |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiNsWalkNamespace |
| * |
| * PARAMETERS: Type - ACPI_OBJECT_TYPE to search for |
| * StartNode - Handle in namespace where search begins |
| * MaxDepth - Depth to which search is to reach |
| * Flags - Whether to unlock the NS before invoking |
| * the callback routine |
| * DescendingCallback - Called during tree descent |
| * when an object of "Type" is found |
| * AscendingCallback - Called during tree ascent |
| * when an object of "Type" is found |
| * Context - Passed to user function(s) above |
| * ReturnValue - from the UserFunction 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 StartHandle. |
| * The callback function is called whenever a node that matches |
| * the type parameter is found. If the callback 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 callback function(s) can be |
| * tailored to each task, whether it is a print function, |
| * a compare function, etc. |
| * |
| ******************************************************************************/ |
| |
| ACPI_STATUS |
| AcpiNsWalkNamespace ( |
| ACPI_OBJECT_TYPE Type, |
| ACPI_HANDLE StartNode, |
| UINT32 MaxDepth, |
| UINT32 Flags, |
| ACPI_WALK_CALLBACK DescendingCallback, |
| ACPI_WALK_CALLBACK AscendingCallback, |
| void *Context, |
| void **ReturnValue) |
| { |
| ACPI_STATUS Status; |
| ACPI_STATUS MutexStatus; |
| ACPI_NAMESPACE_NODE *ChildNode; |
| ACPI_NAMESPACE_NODE *ParentNode; |
| ACPI_OBJECT_TYPE ChildType; |
| UINT32 Level; |
| BOOLEAN NodePreviouslyVisited = FALSE; |
| |
| |
| ACPI_FUNCTION_TRACE (NsWalkNamespace); |
| |
| |
| /* Special case for the namespace Root Node */ |
| |
| if (StartNode == ACPI_ROOT_OBJECT) |
| { |
| StartNode = AcpiGbl_RootNode; |
| } |
| |
| /* Null child means "get first node" */ |
| |
| ParentNode = StartNode; |
| ChildNode = AcpiNsGetNextNode (ParentNode, NULL); |
| ChildType = 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 (StartEntry) |
| */ |
| while (Level > 0 && ChildNode) |
| { |
| Status = AE_OK; |
| |
| /* Found next child, get the type if we are not searching for ANY */ |
| |
| if (Type != ACPI_TYPE_ANY) |
| { |
| ChildType = ChildNode->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 ((ChildNode->Flags & ANOBJ_TEMPORARY) && |
| !(Flags & ACPI_NS_WALK_TEMP_NODES)) |
| { |
| Status = AE_CTRL_DEPTH; |
| } |
| |
| /* Type must match requested type */ |
| |
| else if (ChildType == Type) |
| { |
| /* |
| * Found a matching node, invoke the user callback function. |
| * Unlock the namespace if flag is set. |
| */ |
| if (Flags & ACPI_NS_WALK_UNLOCK) |
| { |
| MutexStatus = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE); |
| if (ACPI_FAILURE (MutexStatus)) |
| { |
| return_ACPI_STATUS (MutexStatus); |
| } |
| } |
| |
| /* |
| * Invoke the user function, either descending, ascending, |
| * or both. |
| */ |
| if (!NodePreviouslyVisited) |
| { |
| if (DescendingCallback) |
| { |
| Status = DescendingCallback (ChildNode, Level, |
| Context, ReturnValue); |
| } |
| } |
| else |
| { |
| if (AscendingCallback) |
| { |
| Status = AscendingCallback (ChildNode, Level, |
| Context, ReturnValue); |
| } |
| } |
| |
| if (Flags & ACPI_NS_WALK_UNLOCK) |
| { |
| MutexStatus = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE); |
| if (ACPI_FAILURE (MutexStatus)) |
| { |
| return_ACPI_STATUS (MutexStatus); |
| } |
| } |
| |
| 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 (!NodePreviouslyVisited && |
| (Level < MaxDepth) && |
| (Status != AE_CTRL_DEPTH)) |
| { |
| if (ChildNode->Child) |
| { |
| /* There is at least one child of this node, visit it */ |
| |
| Level++; |
| ParentNode = ChildNode; |
| ChildNode = AcpiNsGetNextNode (ParentNode, NULL); |
| continue; |
| } |
| } |
| |
| /* No more children, re-visit this node */ |
| |
| if (!NodePreviouslyVisited) |
| { |
| NodePreviouslyVisited = TRUE; |
| continue; |
| } |
| |
| /* No more children, visit peers */ |
| |
| ChildNode = AcpiNsGetNextNode (ParentNode, ChildNode); |
| if (ChildNode) |
| { |
| NodePreviouslyVisited = FALSE; |
| } |
| |
| /* No peers, re-visit parent */ |
| |
| else |
| { |
| /* |
| * No more children of this node (AcpiNsGetNextNode failed), go |
| * back upwards in the namespace tree to the node's parent. |
| */ |
| Level--; |
| ChildNode = ParentNode; |
| ParentNode = ParentNode->Parent; |
| |
| NodePreviouslyVisited = TRUE; |
| } |
| } |
| |
| /* Complete walk, not terminated by user function */ |
| |
| return_ACPI_STATUS (AE_OK); |
| } |
