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

/*******************************************************************************
 *
 * Module Name: nssearch - Namespace search
 *
 ******************************************************************************/

/*
 * Copyright (C) 2000 - 2008, 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("nssearch")

/* Local prototypes */
static acpi_status
acpi_ns_search_parent_tree(u32 target_name,
			   struct acpi_namespace_node *node,
			   acpi_object_type type,
			   struct acpi_namespace_node **return_node);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_search_one_scope
 *
 * PARAMETERS:  target_name     - Ascii ACPI name to search for
 *              parent_node     - Starting node where search will begin
 *              Type            - Object type to match
 *              return_node     - 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
acpi_ns_search_one_scope(u32 target_name,
			 struct acpi_namespace_node *parent_node,
			 acpi_object_type type,
			 struct acpi_namespace_node **return_node)
{
	struct acpi_namespace_node *node;

	ACPI_FUNCTION_TRACE(ns_search_one_scope);

#ifdef ACPI_DEBUG_OUTPUT
	if (ACPI_LV_NAMES & acpi_dbg_level) {
		char *scope_name;

		scope_name = acpi_ns_get_external_pathname(parent_node);
		if (scope_name) {
			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
					  "Searching %s (%p) For [%4.4s] (%s)\n",
					  scope_name, parent_node,
					  ACPI_CAST_PTR(char, &target_name),
					  acpi_ut_get_type_name(type)));

			ACPI_FREE(scope_name);
		}
	}
#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 = parent_node->child;
	while (node) {

		/* Check for match against the name */

		if (node->name.integer == target_name) {

			/* Resolve a control method alias if any */

			if (acpi_ns_get_type(node) ==
			    ACPI_TYPE_LOCAL_METHOD_ALIAS) {
				node =
				    ACPI_CAST_PTR(struct 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, &target_name),
					  acpi_ut_get_type_name(node->type),
					  node,
					  acpi_ut_get_node_name(parent_node),
					  parent_node));

			*return_node = node;
			return_ACPI_STATUS(AE_OK);
		}

		/*
		 * The last entry in the list points back to the parent,
		 * so a flag is used to indicate the end-of-list
		 */
		if (node->flags & ANOBJ_END_OF_PEER_LIST) {

			/* Searched entire list, we are done */

			break;
		}

		/* 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, &target_name),
			  acpi_ut_get_type_name(type),
			  acpi_ut_get_node_name(parent_node), parent_node,
			  parent_node->child));

	return_ACPI_STATUS(AE_NOT_FOUND);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_search_parent_tree
 *
 * PARAMETERS:  target_name     - Ascii ACPI name to search for
 *              Node            - Starting node where search will begin
 *              Type            - Object type to match
 *              return_node     - 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 acpi_ns_local().
 *
 *              "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
acpi_ns_search_parent_tree(u32 target_name,
			   struct acpi_namespace_node *node,
			   acpi_object_type type,
			   struct acpi_namespace_node **return_node)
{
	acpi_status status;
	struct acpi_namespace_node *parent_node;

	ACPI_FUNCTION_TRACE(ns_search_parent_tree);

	parent_node = acpi_ns_get_parent_node(node);

	/*
	 * 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 (!parent_node) {
		ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "[%4.4s] has no parent\n",
				  ACPI_CAST_PTR(char, &target_name)));
		return_ACPI_STATUS(AE_NOT_FOUND);
	}

	if (acpi_ns_local(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, &target_name),
				  acpi_ut_get_type_name(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",
			  acpi_ut_get_node_name(parent_node),
			  ACPI_CAST_PTR(char, &target_name)));

	/* Search parents until target is found or we have backed up to the root */

	while (parent_node) {
		/*
		 * 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 =
		    acpi_ns_search_one_scope(target_name, parent_node,
					     ACPI_TYPE_ANY, return_node);
		if (ACPI_SUCCESS(status)) {
			return_ACPI_STATUS(status);
		}

		/* Not found here, go up another level (until we reach the root) */

		parent_node = acpi_ns_get_parent_node(parent_node);
	}

	/* Not found in parent tree */

	return_ACPI_STATUS(AE_NOT_FOUND);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_search_and_enter
 *
 * PARAMETERS:  target_name         - Ascii ACPI name to search for (4 chars)
 *              walk_state          - Current state of the walk
 *              Node                - Starting node where search will begin
 *              interpreter_mode    - Add names only in ACPI_MODE_LOAD_PASS_x.
 *                                    Otherwise,search only.
 *              Type                - Object type to match
 *              Flags               - Flags describing the search restrictions
 *              return_node         - 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
acpi_ns_search_and_enter(u32 target_name,
			 struct acpi_walk_state *walk_state,
			 struct acpi_namespace_node *node,
			 acpi_interpreter_mode interpreter_mode,
			 acpi_object_type type,
			 u32 flags, struct acpi_namespace_node **return_node)
{
	acpi_status status;
	struct acpi_namespace_node *new_node;

	ACPI_FUNCTION_TRACE(ns_search_and_enter);

	/* Parameter validation */

	if (!node || !target_name || !return_node) {
		ACPI_ERROR((AE_INFO,
			    "Null parameter: Node %p Name %X ReturnNode %p",
			    node, target_name, return_node));
		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.
	 */
	if (!acpi_ut_valid_acpi_name(target_name)) {
		target_name =
		    acpi_ut_repair_name(ACPI_CAST_PTR(char, &target_name));

		/* Report warning only if in strict mode or debug mode */

		if (!acpi_gbl_enable_interpreter_slack) {
			ACPI_WARNING((AE_INFO,
				      "Found bad character(s) in name, repaired: [%4.4s]\n",
				      ACPI_CAST_PTR(char, &target_name)));
		} else {
			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
					  "Found bad character(s) in name, repaired: [%4.4s]\n",
					  ACPI_CAST_PTR(char, &target_name)));
		}
	}

	/* Try to find the name in the namespace level specified by the caller */

	*return_node = ACPI_ENTRY_NOT_FOUND;
	status = acpi_ns_search_one_scope(target_name, node, type, return_node);
	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) && (flags & ACPI_NS_ERROR_IF_FOUND)) {
			status = AE_ALREADY_EXISTS;
		}

		/* 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 ((interpreter_mode != ACPI_IMODE_LOAD_PASS1) &&
	    (flags & ACPI_NS_SEARCH_PARENT)) {
		/*
		 * Not found at this level - search parent tree according to the
		 * ACPI specification
		 */
		status =
		    acpi_ns_search_parent_tree(target_name, node, type,
					       return_node);
		if (ACPI_SUCCESS(status)) {
			return_ACPI_STATUS(status);
		}
	}

	/* In execute mode, just search, never add names. Exit now */

	if (interpreter_mode == ACPI_IMODE_EXECUTE) {
		ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
				  "%4.4s Not found in %p [Not adding]\n",
				  ACPI_CAST_PTR(char, &target_name), node));

		return_ACPI_STATUS(AE_NOT_FOUND);
	}

	/* Create the new named object */

	new_node = acpi_ns_create_node(target_name);
	if (!new_node) {
		return_ACPI_STATUS(AE_NO_MEMORY);
	}
#ifdef ACPI_ASL_COMPILER

	/* Node is an object defined by an External() statement */

	if (flags & ACPI_NS_EXTERNAL) {
		new_node->flags |= ANOBJ_IS_EXTERNAL;
	}
#endif

	if (flags & ACPI_NS_TEMPORARY) {
		new_node->flags |= ANOBJ_TEMPORARY;
	}

	/* Install the new object into the parent's list of children */

	acpi_ns_install_node(walk_state, node, new_node, type);
	*return_node = new_node;
	return_ACPI_STATUS(AE_OK);
}
Commit	Line	Data
1da177e4 LT	1	/*******************************************************************************
	2	*
	3	* Module Name: nssearch - Namespace search
	4	*
	5	******************************************************************************/
	6
	7	/*
75a44ce0	8	* Copyright (C) 2000 - 2008, 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("nssearch")
1da177e4	50
44f6c012	51	/* Local prototypes */
44f6c012	52	static acpi_status
4be44fcd LB	53	acpi_ns_search_parent_tree(u32 target_name,
	54	struct acpi_namespace_node *node,
	55	acpi_object_type type,
	56	struct acpi_namespace_node **return_node);
1da177e4 LT	57
	58	/*******************************************************************************
	59	*
4119532c	60	* FUNCTION: acpi_ns_search_one_scope
1da177e4	61	*
44f6c012	62	* PARAMETERS: target_name - Ascii ACPI name to search for
4119532c	63	* parent_node - Starting node where search will begin
44f6c012 RM	64	* Type - Object type to match
44f6c012 RM	65	* return_node - Where the matched Named obj is returned
1da177e4 LT	66	*
	67	* RETURN: Status
	68	*
4119532c	69	* DESCRIPTION: Search a single level of the namespace. Performs a
1da177e4 LT	70	* simple search of the specified level, and does not add
	71	* entries or search parents.
	72	*
	73	*
	74	* Named object lists are built (and subsequently dumped) in the
	75	* order in which the names are encountered during the namespace load;
	76	*
	77	* All namespace searching is linear in this implementation, but
	78	* could be easily modified to support any improved search
4119532c	79	* algorithm. However, the linear search was chosen for simplicity
1da177e4 LT	80	* and because the trees are small and the other interpreter
	81	* execution overhead is relatively high.
	82	*
4119532c BM	83	* Note: CPU execution analysis has shown that the AML interpreter spends
	84	* a very small percentage of its time searching the namespace. Therefore,
	85	* the linear search seems to be sufficient, as there would seem to be
	86	* little value in improving the search.
	87	*
1da177e4 LT	88	******************************************************************************/
	89
	90	acpi_status
4119532c BM	91	acpi_ns_search_one_scope(u32 target_name,
	92	struct acpi_namespace_node *parent_node,
	93	acpi_object_type type,
	94	struct acpi_namespace_node **return_node)
1da177e4	95	{
4119532c	96	struct acpi_namespace_node *node;
1da177e4	97
4119532c	98	ACPI_FUNCTION_TRACE(ns_search_one_scope);
1da177e4 LT	99
	100	#ifdef ACPI_DEBUG_OUTPUT
	101	if (ACPI_LV_NAMES & acpi_dbg_level) {
4be44fcd	102	char *scope_name;
1da177e4	103
4119532c	104	scope_name = acpi_ns_get_external_pathname(parent_node);
1da177e4	105	if (scope_name) {
4be44fcd LB	106	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
4be44fcd LB	107	"Searching %s (%p) For [%4.4s] (%s)\n",
4119532c BM	108	scope_name, parent_node,
4119532c BM	109	ACPI_CAST_PTR(char, &target_name),
4be44fcd	110	acpi_ut_get_type_name(type)));
1da177e4	111
8313524a	112	ACPI_FREE(scope_name);
1da177e4 LT	113	}
	114	}
	115	#endif
	116
	117	/*
	118	* Search for name at this namespace level, which is to say that we
	119	* must search for the name among the children of this object
	120	*/
4119532c BM	121	node = parent_node->child;
4119532c BM	122	while (node) {
52fc0b02	123
1da177e4 LT	124	/* Check for match against the name */
1da177e4 LT	125
4119532c	126	if (node->name.integer == target_name) {
52fc0b02	127
1da177e4 LT	128	/* Resolve a control method alias if any */
1da177e4 LT	129
4119532c	130	if (acpi_ns_get_type(node) ==
4be44fcd	131	ACPI_TYPE_LOCAL_METHOD_ALIAS) {
4119532c	132	node =
4be44fcd	133	ACPI_CAST_PTR(struct acpi_namespace_node,
4119532c	134	node->object);
1da177e4 LT	135	}
1da177e4 LT	136
793c2388 BM	137	/* Found matching entry */
793c2388 BM	138
4be44fcd LB	139	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
4be44fcd LB	140	"Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n",
defba1d8	141	ACPI_CAST_PTR(char, &target_name),
4119532c BM	142	acpi_ut_get_type_name(node->type),
	143	node,
	144	acpi_ut_get_node_name(parent_node),
	145	parent_node));
1da177e4	146
4119532c	147	*return_node = node;
4be44fcd	148	return_ACPI_STATUS(AE_OK);
1da177e4 LT	149	}
	150
	151	/*
	152	* The last entry in the list points back to the parent,
	153	* so a flag is used to indicate the end-of-list
	154	*/
4119532c	155	if (node->flags & ANOBJ_END_OF_PEER_LIST) {
52fc0b02	156
1da177e4 LT	157	/* Searched entire list, we are done */
	158
	159	break;
	160	}
	161
	162	/* Didn't match name, move on to the next peer object */
	163
4119532c	164	node = node->peer;
1da177e4 LT	165	}
	166
	167	/* Searched entire namespace level, not found */
	168
4be44fcd	169	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
d4913dc6 BM	170	"Name [%4.4s] (%s) not found in search in scope [%4.4s] "
d4913dc6 BM	171	"%p first child %p\n",
defba1d8 BM	172	ACPI_CAST_PTR(char, &target_name),
defba1d8 BM	173	acpi_ut_get_type_name(type),
4119532c BM	174	acpi_ut_get_node_name(parent_node), parent_node,
4119532c BM	175	parent_node->child));
1da177e4	176
4be44fcd	177	return_ACPI_STATUS(AE_NOT_FOUND);
1da177e4 LT	178	}
1da177e4 LT	179
1da177e4 LT	180	/*******************************************************************************
	181	*
	182	* FUNCTION: acpi_ns_search_parent_tree
	183	*
44f6c012 RM	184	* PARAMETERS: target_name - Ascii ACPI name to search for
	185	* Node - Starting node where search will begin
	186	* Type - Object type to match
	187	* return_node - Where the matched Node is returned
1da177e4 LT	188	*
	189	* RETURN: Status
	190	*
	191	* DESCRIPTION: Called when a name has not been found in the current namespace
4119532c	192	* level. Before adding it or giving up, ACPI scope rules require
1da177e4 LT	193	* searching enclosing scopes in cases identified by acpi_ns_local().
	194	*
	195	* "A name is located by finding the matching name in the current
	196	* name space, and then in the parent name space. If the parent
	197	* name space does not contain the name, the search continues
	198	* recursively until either the name is found or the name space
4119532c	199	* does not have a parent (the root of the name space). This
1da177e4 LT	200	* indicates that the name is not found" (From ACPI Specification,
	201	* section 5.3)
	202	*
	203	******************************************************************************/
	204
	205	static acpi_status
4be44fcd LB	206	acpi_ns_search_parent_tree(u32 target_name,
	207	struct acpi_namespace_node *node,
	208	acpi_object_type type,
	209	struct acpi_namespace_node **return_node)
1da177e4	210	{
4be44fcd LB	211	acpi_status status;
4be44fcd LB	212	struct acpi_namespace_node *parent_node;
1da177e4	213
b229cf92	214	ACPI_FUNCTION_TRACE(ns_search_parent_tree);
1da177e4	215
4be44fcd	216	parent_node = acpi_ns_get_parent_node(node);
1da177e4 LT	217
	218	/*
	219	* If there is no parent (i.e., we are at the root) or type is "local",
	220	* we won't be searching the parent tree.
	221	*/
	222	if (!parent_node) {
4be44fcd	223	ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "[%4.4s] has no parent\n",
defba1d8	224	ACPI_CAST_PTR(char, &target_name)));
4be44fcd	225	return_ACPI_STATUS(AE_NOT_FOUND);
1da177e4 LT	226	}
1da177e4 LT	227
4be44fcd LB	228	if (acpi_ns_local(type)) {
	229	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
	230	"[%4.4s] type [%s] must be local to this scope (no parent search)\n",
defba1d8	231	ACPI_CAST_PTR(char, &target_name),
4be44fcd LB	232	acpi_ut_get_type_name(type)));
4be44fcd LB	233	return_ACPI_STATUS(AE_NOT_FOUND);
1da177e4 LT	234	}
	235
	236	/* Search the parent tree */
	237
4be44fcd LB	238	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
	239	"Searching parent [%4.4s] for [%4.4s]\n",
	240	acpi_ut_get_node_name(parent_node),
defba1d8	241	ACPI_CAST_PTR(char, &target_name)));
1da177e4	242
d4913dc6 BM	243	/* Search parents until target is found or we have backed up to the root */
d4913dc6 BM	244
1da177e4 LT	245	while (parent_node) {
1da177e4 LT	246	/*
4119532c	247	* Search parent scope. Use TYPE_ANY because we don't care about the
1da177e4	248	* object type at this point, we only care about the existence of
4119532c	249	* the actual name we are searching for. Typechecking comes later.
1da177e4	250	*/
4119532c BM	251	status =
4119532c BM	252	acpi_ns_search_one_scope(target_name, parent_node,
4be44fcd LB	253	ACPI_TYPE_ANY, return_node);
	254	if (ACPI_SUCCESS(status)) {
	255	return_ACPI_STATUS(status);
1da177e4 LT	256	}
1da177e4 LT	257
793c2388 BM	258	/* Not found here, go up another level (until we reach the root) */
793c2388 BM	259
4be44fcd	260	parent_node = acpi_ns_get_parent_node(parent_node);
1da177e4 LT	261	}
	262
	263	/* Not found in parent tree */
	264
4be44fcd	265	return_ACPI_STATUS(AE_NOT_FOUND);
1da177e4 LT	266	}
1da177e4 LT	267
1da177e4 LT	268	/*******************************************************************************
	269	*
	270	* FUNCTION: acpi_ns_search_and_enter
	271	*
	272	* PARAMETERS: target_name - Ascii ACPI name to search for (4 chars)
	273	* walk_state - Current state of the walk
44f6c012	274	* Node - Starting node where search will begin
1da177e4 LT	275	* interpreter_mode - Add names only in ACPI_MODE_LOAD_PASS_x.
	276	* Otherwise,search only.
	277	* Type - Object type to match
	278	* Flags - Flags describing the search restrictions
44f6c012	279	* return_node - Where the Node is returned
1da177e4 LT	280	*
	281	* RETURN: Status
	282	*
	283	* DESCRIPTION: Search for a name segment in a single namespace level,
4119532c	284	* optionally adding it if it is not found. If the passed
1da177e4 LT	285	* Type is not Any and the type previously stored in the
	286	* entry was Any (i.e. unknown), update the stored type.
	287	*
	288	* In ACPI_IMODE_EXECUTE, search only.
	289	* In other modes, search and add if not found.
	290	*
	291	******************************************************************************/
	292
	293	acpi_status
4be44fcd LB	294	acpi_ns_search_and_enter(u32 target_name,
	295	struct acpi_walk_state *walk_state,
	296	struct acpi_namespace_node *node,
	297	acpi_interpreter_mode interpreter_mode,
	298	acpi_object_type type,
	299	u32 flags, struct acpi_namespace_node **return_node)
1da177e4	300	{
4be44fcd LB	301	acpi_status status;
4be44fcd LB	302	struct acpi_namespace_node *new_node;
1da177e4	303
b229cf92	304	ACPI_FUNCTION_TRACE(ns_search_and_enter);
1da177e4 LT	305
	306	/* Parameter validation */
	307
	308	if (!node \|\| !target_name \|\| !return_node) {
b8e4d893	309	ACPI_ERROR((AE_INFO,
958dd242	310	"Null parameter: Node %p Name %X ReturnNode %p",
b8e4d893	311	node, target_name, return_node));
4be44fcd	312	return_ACPI_STATUS(AE_BAD_PARAMETER);
1da177e4 LT	313	}
1da177e4 LT	314
793c2388 BM	315	/*
	316	* Name must consist of valid ACPI characters. We will repair the name if
	317	* necessary because we don't want to abort because of this, but we want
	318	* all namespace names to be printable. A warning message is appropriate.
	319	*
	320	* This issue came up because there are in fact machines that exhibit
	321	* this problem, and we want to be able to enable ACPI support for them,
	322	* even though there are a few bad names.
	323	*/
4be44fcd	324	if (!acpi_ut_valid_acpi_name(target_name)) {
3d81b236 BM	325	target_name =
3d81b236 BM	326	acpi_ut_repair_name(ACPI_CAST_PTR(char, &target_name));
793c2388 BM	327
	328	/* Report warning only if in strict mode or debug mode */
	329
	330	if (!acpi_gbl_enable_interpreter_slack) {
	331	ACPI_WARNING((AE_INFO,
	332	"Found bad character(s) in name, repaired: [%4.4s]\n",
	333	ACPI_CAST_PTR(char, &target_name)));
	334	} else {
23d3e055	335	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
793c2388 BM	336	"Found bad character(s) in name, repaired: [%4.4s]\n",
	337	ACPI_CAST_PTR(char, &target_name)));
	338	}
1da177e4 LT	339	}
	340
	341	/* Try to find the name in the namespace level specified by the caller */
	342
	343	*return_node = ACPI_ENTRY_NOT_FOUND;
4119532c	344	status = acpi_ns_search_one_scope(target_name, node, type, return_node);
1da177e4 LT	345	if (status != AE_NOT_FOUND) {
	346	/*
	347	* If we found it AND the request specifies that a find is an error,
	348	* return the error
	349	*/
4be44fcd	350	if ((status == AE_OK) && (flags & ACPI_NS_ERROR_IF_FOUND)) {
1da177e4 LT	351	status = AE_ALREADY_EXISTS;
	352	}
	353
793c2388 BM	354	/* Either found it or there was an error: finished either way */
793c2388 BM	355
4be44fcd	356	return_ACPI_STATUS(status);
1da177e4 LT	357	}
	358
	359	/*
4119532c	360	* The name was not found. If we are NOT performing the first pass
1da177e4 LT	361	* (name entry) of loading the namespace, search the parent tree (all the
1da177e4 LT	362	* way to the root if necessary.) We don't want to perform the parent
4119532c	363	* search when the namespace is actually being loaded. We want to perform
1da177e4 LT	364	* the search when namespace references are being resolved (load pass 2)
	365	* and during the execution phase.
	366	*/
	367	if ((interpreter_mode != ACPI_IMODE_LOAD_PASS1) &&
4be44fcd	368	(flags & ACPI_NS_SEARCH_PARENT)) {
1da177e4 LT	369	/*
	370	* Not found at this level - search parent tree according to the
	371	* ACPI specification
	372	*/
4be44fcd LB	373	status =
	374	acpi_ns_search_parent_tree(target_name, node, type,
	375	return_node);
	376	if (ACPI_SUCCESS(status)) {
	377	return_ACPI_STATUS(status);
1da177e4 LT	378	}
	379	}
	380
793c2388 BM	381	/* In execute mode, just search, never add names. Exit now */
793c2388 BM	382
1da177e4	383	if (interpreter_mode == ACPI_IMODE_EXECUTE) {
4be44fcd LB	384	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
4be44fcd LB	385	"%4.4s Not found in %p [Not adding]\n",
defba1d8	386	ACPI_CAST_PTR(char, &target_name), node));
1da177e4	387
4be44fcd	388	return_ACPI_STATUS(AE_NOT_FOUND);
1da177e4 LT	389	}
	390
	391	/* Create the new named object */
	392
4be44fcd	393	new_node = acpi_ns_create_node(target_name);
1da177e4	394	if (!new_node) {
4be44fcd	395	return_ACPI_STATUS(AE_NO_MEMORY);
1da177e4	396	}
958dd242	397	#ifdef ACPI_ASL_COMPILER
d4913dc6 BM	398
	399	/* Node is an object defined by an External() statement */
	400
958dd242 BM	401	if (flags & ACPI_NS_EXTERNAL) {
	402	new_node->flags \|= ANOBJ_IS_EXTERNAL;
	403	}
	404	#endif
1da177e4	405
d1fdda83 BM	406	if (flags & ACPI_NS_TEMPORARY) {
	407	new_node->flags \|= ANOBJ_TEMPORARY;
	408	}
	409
1da177e4 LT	410	/* Install the new object into the parent's list of children */
1da177e4 LT	411
4be44fcd	412	acpi_ns_install_node(walk_state, node, new_node, type);
1da177e4	413	*return_node = new_node;
4be44fcd	414	return_ACPI_STATUS(AE_OK);
1da177e4	415	}