mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-27 13:05:03 +08:00
33ccf4f817
[ Upstream commit0c9992315e] ACPICA commit b1c3656ef4950098e530be68d4b589584f06cddc Prevent acpi_ns_walk_namespace() from crashing when called with start_node equal to ACPI_ROOT_OBJECT if the Namespace has not been instantiated yet and acpi_gbl_root_node is NULL. For instance, this can happen if the kernel is run with "acpi=off" in the command line. Link:b1c3656ef4Link: https://lore.kernel.org/linux-acpi/CAJZ5v0hJWW_vZ3wwajE7xT38aWjY7cZyvqMJpXHzUL98-SiCVQ@mail.gmail.com/ Reported-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
328 lines
9.4 KiB
C
328 lines
9.4 KiB
C
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
|
|
/******************************************************************************
|
|
*
|
|
* Module Name: nswalk - Functions for walking the ACPI namespace
|
|
*
|
|
* Copyright (C) 2000 - 2021, Intel Corp.
|
|
*
|
|
*****************************************************************************/
|
|
|
|
#include <acpi/acpi.h>
|
|
#include "accommon.h"
|
|
#include "acnamesp.h"
|
|
|
|
#define _COMPONENT ACPI_NAMESPACE
|
|
ACPI_MODULE_NAME("nswalk")
|
|
|
|
/*******************************************************************************
|
|
*
|
|
* FUNCTION: acpi_ns_get_next_node
|
|
*
|
|
* PARAMETERS: 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(struct acpi_namespace_node
|
|
*parent_node,
|
|
struct acpi_namespace_node
|
|
*child_node)
|
|
{
|
|
ACPI_FUNCTION_ENTRY();
|
|
|
|
if (!child_node) {
|
|
|
|
/* It's really the parent's _scope_ that we want */
|
|
|
|
return (parent_node->child);
|
|
}
|
|
|
|
/* Otherwise just return the next peer */
|
|
|
|
return (child_node->peer);
|
|
}
|
|
|
|
/*******************************************************************************
|
|
*
|
|
* FUNCTION: acpi_ns_get_next_node_typed
|
|
*
|
|
* 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_typed(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();
|
|
|
|
next_node = acpi_ns_get_next_node(parent_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 peer node */
|
|
|
|
next_node = next_node->peer;
|
|
}
|
|
|
|
/* 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
|
|
* flags - Whether to unlock the NS before invoking
|
|
* the callback routine
|
|
* descending_callback - Called during tree descent
|
|
* when an object of "Type" is found
|
|
* ascending_callback - Called during tree ascent
|
|
* when an object of "Type" is found
|
|
* context - Passed to user function(s) above
|
|
* 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 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
|
|
acpi_ns_walk_namespace(acpi_object_type type,
|
|
acpi_handle start_node,
|
|
u32 max_depth,
|
|
u32 flags,
|
|
acpi_walk_callback descending_callback,
|
|
acpi_walk_callback ascending_callback,
|
|
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;
|
|
u8 node_previously_visited = FALSE;
|
|
|
|
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;
|
|
if (!start_node) {
|
|
return_ACPI_STATUS(AE_NO_NAMESPACE);
|
|
}
|
|
}
|
|
|
|
/* Null child means "get first node" */
|
|
|
|
parent_node = start_node;
|
|
child_node = acpi_ns_get_next_node(parent_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 && child_node) {
|
|
status = AE_OK;
|
|
|
|
/* Found next child, get the type if we are not searching for ANY */
|
|
|
|
if (type != ACPI_TYPE_ANY) {
|
|
child_type = child_node->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 ((child_node->flags & ANOBJ_TEMPORARY) &&
|
|
!(flags & ACPI_NS_WALK_TEMP_NODES)) {
|
|
status = AE_CTRL_DEPTH;
|
|
}
|
|
|
|
/* Type must match requested type */
|
|
|
|
else if (child_type == type) {
|
|
/*
|
|
* Found a matching node, invoke the user callback function.
|
|
* Unlock the namespace if flag is set.
|
|
*/
|
|
if (flags & ACPI_NS_WALK_UNLOCK) {
|
|
mutex_status =
|
|
acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
|
|
if (ACPI_FAILURE(mutex_status)) {
|
|
return_ACPI_STATUS(mutex_status);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Invoke the user function, either descending, ascending,
|
|
* or both.
|
|
*/
|
|
if (!node_previously_visited) {
|
|
if (descending_callback) {
|
|
status =
|
|
descending_callback(child_node,
|
|
level, context,
|
|
return_value);
|
|
}
|
|
} else {
|
|
if (ascending_callback) {
|
|
status =
|
|
ascending_callback(child_node,
|
|
level, context,
|
|
return_value);
|
|
}
|
|
}
|
|
|
|
if (flags & ACPI_NS_WALK_UNLOCK) {
|
|
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 (!node_previously_visited &&
|
|
(level < max_depth) && (status != AE_CTRL_DEPTH)) {
|
|
if (child_node->child) {
|
|
|
|
/* There is at least one child of this node, visit it */
|
|
|
|
level++;
|
|
parent_node = child_node;
|
|
child_node =
|
|
acpi_ns_get_next_node(parent_node, NULL);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
/* No more children, re-visit this node */
|
|
|
|
if (!node_previously_visited) {
|
|
node_previously_visited = TRUE;
|
|
continue;
|
|
}
|
|
|
|
/* No more children, visit peers */
|
|
|
|
child_node = acpi_ns_get_next_node(parent_node, child_node);
|
|
if (child_node) {
|
|
node_previously_visited = FALSE;
|
|
}
|
|
|
|
/* No peers, re-visit parent */
|
|
|
|
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 = parent_node->parent;
|
|
|
|
node_previously_visited = TRUE;
|
|
}
|
|
}
|
|
|
|
/* Complete walk, not terminated by user function */
|
|
|
|
return_ACPI_STATUS(AE_OK);
|
|
}
|