[linux-2.6-block.git] / drivers / acpi / acpica / nswalk.c

/******************************************************************************
 *
 * 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/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;
	}

	/* 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);
}
Commit	Line	Data
1da177e4 LT	1	/******************************************************************************
	2	*
	3	* Module Name: nswalk - Functions for walking the ACPI namespace
	4	*
	5	*****************************************************************************/
	6
	7	/*
c8100dc4	8	* Copyright (C) 2000 - 2016, Intel Corp.
1da177e4 LT	9	* All rights reserved.
	10	*
	11	* Redistribution and use in source and binary forms, with or without
	12	* modification, are permitted provided that the following conditions
	13	* are met:
	14	* 1. Redistributions of source code must retain the above copyright
	15	* notice, this list of conditions, and the following disclaimer,
	16	* without modification.
	17	* 2. Redistributions in binary form must reproduce at minimum a disclaimer
	18	* substantially similar to the "NO WARRANTY" disclaimer below
	19	* ("Disclaimer") and any redistribution must be conditioned upon
	20	* including a substantially similar Disclaimer requirement for further
	21	* binary redistribution.
	22	* 3. Neither the names of the above-listed copyright holders nor the names
	23	* of any contributors may be used to endorse or promote products derived
	24	* from this software without specific prior written permission.
	25	*
	26	* Alternatively, this software may be distributed under the terms of the
	27	* GNU General Public License ("GPL") version 2 as published by the Free
	28	* Software Foundation.
	29	*
	30	* NO WARRANTY
	31	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	32	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	33	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
	34	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	35	* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	36	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	37	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	38	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	39	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
	40	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	41	* POSSIBILITY OF SUCH DAMAGES.
	42	*/
	43
1da177e4	44	#include <acpi/acpi.h>
e2f7a777 LB	45	#include "accommon.h"
e2f7a777 LB	46	#include "acnamesp.h"
1da177e4	47
1da177e4	48	#define _COMPONENT ACPI_NAMESPACE
4be44fcd	49	ACPI_MODULE_NAME("nswalk")
1da177e4 LT	50
	51	/*******************************************************************************
	52	*
	53	* FUNCTION: acpi_ns_get_next_node
	54	*
8c725bf9	55	* PARAMETERS: parent_node - Parent node whose children we are
44f6c012	56	* getting
1da177e4 LT	57	* child_node - Previous child that was found.
	58	* The NEXT child will be returned
	59	*
	60	* RETURN: struct acpi_namespace_node - Pointer to the NEXT child or NULL if
	61	* none is found.
	62	*
73a3090a BM	63	* DESCRIPTION: Return the next peer node within the namespace. If Handle
73a3090a BM	64	* is valid, Scope is ignored. Otherwise, the first node
1da177e4 LT	65	* within Scope is returned.
	66	*
	67	******************************************************************************/
8c725bf9 BM	68	struct acpi_namespace_node *acpi_ns_get_next_node(struct acpi_namespace_node
	69	*parent_node,
	70	struct acpi_namespace_node
4be44fcd	71	*child_node)
1da177e4	72	{
4be44fcd	73	ACPI_FUNCTION_ENTRY();
1da177e4 LT	74
1da177e4 LT	75	if (!child_node) {
52fc0b02	76
1da177e4 LT	77	/* It's really the parent's _scope_ that we want */
1da177e4 LT	78
9c0d7939	79	return (parent_node->child);
1da177e4 LT	80	}
1da177e4 LT	81
8c725bf9 BM	82	/* Otherwise just return the next peer */
8c725bf9 BM	83
9c0d7939	84	return (child_node->peer);
8c725bf9 BM	85	}
	86
	87	/*******************************************************************************
	88	*
	89	* FUNCTION: acpi_ns_get_next_node_typed
	90	*
ba494bee	91	* PARAMETERS: type - Type of node to be searched for
8c725bf9 BM	92	* parent_node - Parent node whose children we are
	93	* getting
	94	* child_node - Previous child that was found.
	95	* The NEXT child will be returned
	96	*
	97	* RETURN: struct acpi_namespace_node - Pointer to the NEXT child or NULL if
	98	* none is found.
	99	*
73a3090a BM	100	* DESCRIPTION: Return the next peer node within the namespace. If Handle
73a3090a BM	101	* is valid, Scope is ignored. Otherwise, the first node
8c725bf9 BM	102	* within Scope is returned.
	103	*
	104	******************************************************************************/
	105
	106	struct acpi_namespace_node *acpi_ns_get_next_node_typed(acpi_object_type type,
	107	struct
	108	acpi_namespace_node
	109	*parent_node,
	110	struct
	111	acpi_namespace_node
	112	*child_node)
	113	{
	114	struct acpi_namespace_node *next_node = NULL;
	115
	116	ACPI_FUNCTION_ENTRY();
	117
	118	next_node = acpi_ns_get_next_node(parent_node, child_node);
	119
	120
1da177e4 LT	121	/* If any type is OK, we are done */
	122
	123	if (type == ACPI_TYPE_ANY) {
52fc0b02	124
1da177e4 LT	125	/* next_node is NULL if we are at the end-of-list */
	126
	127	return (next_node);
	128	}
	129
	130	/* Must search for the node -- but within this scope only */
	131
	132	while (next_node) {
52fc0b02	133
1da177e4 LT	134	/* If type matches, we are done */
	135
	136	if (next_node->type == type) {
	137	return (next_node);
	138	}
	139
c45b5c09	140	/* Otherwise, move on to the next peer node */
1da177e4	141
c45b5c09	142	next_node = next_node->peer;
1da177e4 LT	143	}
	144
	145	/* Not found */
	146
	147	return (NULL);
	148	}
	149
1da177e4 LT	150	/*******************************************************************************
	151	*
	152	* FUNCTION: acpi_ns_walk_namespace
	153	*
ba494bee	154	* PARAMETERS: type - acpi_object_type to search for
1da177e4 LT	155	* start_node - Handle in namespace where search begins
1da177e4 LT	156	* max_depth - Depth to which search is to reach
ba494bee	157	* flags - Whether to unlock the NS before invoking
1da177e4	158	* the callback routine
4ef17507	159	* descending_callback - Called during tree descent
2263576c	160	* when an object of "Type" is found
4ef17507	161	* ascending_callback - Called during tree ascent
2263576c	162	* when an object of "Type" is found
ba494bee	163	* context - Passed to user function(s) above
2263576c LM	164	* return_value - from the user_function if terminated
2263576c LM	165	* early. Otherwise, returns NULL.
1da177e4 LT	166	* RETURNS: Status
	167	*
	168	* DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
	169	* starting (and ending) at the node specified by start_handle.
2263576c LM	170	* The callback function is called whenever a node that matches
2263576c LM	171	* the type parameter is found. If the callback function returns
d4913dc6 BM	172	* a non-zero value, the search is terminated immediately and
d4913dc6 BM	173	* this value is returned to the caller.
1da177e4 LT	174	*
	175	* The point of this procedure is to provide a generic namespace
	176	* walk routine that can be called from multiple places to
2263576c LM	177	* provide multiple services; the callback function(s) can be
	178	* tailored to each task, whether it is a print function,
	179	* a compare function, etc.
1da177e4 LT	180	*
	181	******************************************************************************/
	182
	183	acpi_status
4be44fcd LB	184	acpi_ns_walk_namespace(acpi_object_type type,
	185	acpi_handle start_node,
	186	u32 max_depth,
d1fdda83	187	u32 flags,
4ef17507 BM	188	acpi_walk_callback descending_callback,
4ef17507 BM	189	acpi_walk_callback ascending_callback,
4be44fcd	190	void context, void *return_value)
1da177e4	191	{
4be44fcd LB	192	acpi_status status;
	193	acpi_status mutex_status;
	194	struct acpi_namespace_node *child_node;
	195	struct acpi_namespace_node *parent_node;
	196	acpi_object_type child_type;
	197	u32 level;
2263576c	198	u8 node_previously_visited = FALSE;
1da177e4	199
b229cf92	200	ACPI_FUNCTION_TRACE(ns_walk_namespace);
1da177e4 LT	201
	202	/* Special case for the namespace Root Node */
	203
	204	if (start_node == ACPI_ROOT_OBJECT) {
	205	start_node = acpi_gbl_root_node;
	206	}
	207
	208	/* Null child means "get first node" */
	209
	210	parent_node = start_node;
2263576c	211	child_node = acpi_ns_get_next_node(parent_node, NULL);
4be44fcd LB	212	child_type = ACPI_TYPE_ANY;
4be44fcd LB	213	level = 1;
1da177e4 LT	214
	215	/*
	216	* Traverse the tree of nodes until we bubble back up to where we
	217	* started. When Level is zero, the loop is done because we have
	218	* bubbled up to (and passed) the original parent handle (start_entry)
	219	*/
2263576c LM	220	while (level > 0 && child_node) {
2263576c LM	221	status = AE_OK;
52fc0b02	222
2263576c	223	/* Found next child, get the type if we are not searching for ANY */
1da177e4	224
2263576c LM	225	if (type != ACPI_TYPE_ANY) {
	226	child_type = child_node->type;
	227	}
3effba32	228
2263576c LM	229	/*
	230	* Ignore all temporary namespace nodes (created during control
	231	* method execution) unless told otherwise. These temporary nodes
	232	* can cause a race condition because they can be deleted during
	233	* the execution of the user function (if the namespace is
	234	* unlocked before invocation of the user function.) Only the
	235	* debugger namespace dump will examine the temporary nodes.
	236	*/
	237	if ((child_node->flags & ANOBJ_TEMPORARY) &&
	238	!(flags & ACPI_NS_WALK_TEMP_NODES)) {
	239	status = AE_CTRL_DEPTH;
	240	}
3effba32	241
2263576c	242	/* Type must match requested type */
1da177e4	243
2263576c	244	else if (child_type == type) {
3effba32	245	/*
2263576c LM	246	* Found a matching node, invoke the user callback function.
2263576c LM	247	* Unlock the namespace if flag is set.
3effba32	248	*/
2263576c LM	249	if (flags & ACPI_NS_WALK_UNLOCK) {
	250	mutex_status =
	251	acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	252	if (ACPI_FAILURE(mutex_status)) {
	253	return_ACPI_STATUS(mutex_status);
	254	}
c1014629 BM	255	}
c1014629 BM	256
2263576c	257	/*
4ef17507	258	* Invoke the user function, either descending, ascending,
2263576c LM	259	* or both.
	260	*/
	261	if (!node_previously_visited) {
4ef17507	262	if (descending_callback) {
2263576c	263	status =
4ef17507 BM	264	descending_callback(child_node,
	265	level, context,
	266	return_value);
1da177e4	267	}
2263576c	268	} else {
4ef17507	269	if (ascending_callback) {
2263576c	270	status =
4ef17507 BM	271	ascending_callback(child_node,
	272	level, context,
	273	return_value);
2263576c LM	274	}
2263576c LM	275	}
1da177e4	276
2263576c LM	277	if (flags & ACPI_NS_WALK_UNLOCK) {
	278	mutex_status =
	279	acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	280	if (ACPI_FAILURE(mutex_status)) {
	281	return_ACPI_STATUS(mutex_status);
1da177e4	282	}
2263576c	283	}
1da177e4	284
2263576c LM	285	switch (status) {
	286	case AE_OK:
	287	case AE_CTRL_DEPTH:
1da177e4	288
2263576c LM	289	/* Just keep going */
2263576c LM	290	break;
1da177e4	291
2263576c	292	case AE_CTRL_TERMINATE:
1da177e4	293
2263576c	294	/* Exit now, with OK status */
1da177e4	295
2263576c	296	return_ACPI_STATUS(AE_OK);
1da177e4	297
2263576c	298	default:
1da177e4	299
2263576c	300	/* All others are valid exceptions */
1da177e4	301
2263576c LM	302	return_ACPI_STATUS(status);
	303	}
	304	}
	305
	306	/*
	307	* Depth first search: Attempt to go down another level in the
73a3090a	308	* namespace if we are allowed to. Don't go any further if we have
2263576c LM	309	* reached the caller specified maximum depth or if the user
	310	* function has specified that the maximum depth has been reached.
	311	*/
	312	if (!node_previously_visited &&
	313	(level < max_depth) && (status != AE_CTRL_DEPTH)) {
	314	if (child_node->child) {
	315
	316	/* There is at least one child of this node, visit it */
	317
	318	level++;
	319	parent_node = child_node;
	320	child_node =
	321	acpi_ns_get_next_node(parent_node, NULL);
	322	continue;
1da177e4	323	}
2263576c	324	}
1da177e4	325
2263576c	326	/* No more children, re-visit this node */
3effba32	327
2263576c LM	328	if (!node_previously_visited) {
	329	node_previously_visited = TRUE;
	330	continue;
	331	}
3effba32	332
2263576c LM	333	/* No more children, visit peers */
	334
	335	child_node = acpi_ns_get_next_node(parent_node, child_node);
	336	if (child_node) {
	337	node_previously_visited = FALSE;
	338	}
	339
	340	/* No peers, re-visit parent */
	341
	342	else {
1da177e4	343	/*
3effba32 BM	344	* No more children of this node (acpi_ns_get_next_node failed), go
3effba32 BM	345	* back upwards in the namespace tree to the node's parent.
1da177e4 LT	346	*/
	347	level--;
	348	child_node = parent_node;
c45b5c09	349	parent_node = parent_node->parent;
2263576c LM	350
2263576c LM	351	node_previously_visited = TRUE;
1da177e4 LT	352	}
	353	}
	354
	355	/* Complete walk, not terminated by user function */
	356
4be44fcd	357	return_ACPI_STATUS(AE_OK);
1da177e4	358	}