1 /*******************************************************************************
3 * Module Name: nssearch - Namespace search
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2006, R. Byron Moore
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
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
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44 #include <acpi/acpi.h>
45 #include <acpi/acnamesp.h>
47 #define _COMPONENT ACPI_NAMESPACE
48 ACPI_MODULE_NAME("nssearch")
50 /* Local prototypes */
52 acpi_ns_search_parent_tree(u32 target_name
,
53 struct acpi_namespace_node
*node
,
54 acpi_object_type type
,
55 struct acpi_namespace_node
**return_node
);
57 /*******************************************************************************
59 * FUNCTION: acpi_ns_search_node
61 * PARAMETERS: target_name - Ascii ACPI name to search for
62 * Node - Starting node where search will begin
63 * Type - Object type to match
64 * return_node - Where the matched Named obj is returned
68 * DESCRIPTION: Search a single level of the namespace. Performs a
69 * simple search of the specified level, and does not add
70 * entries or search parents.
73 * Named object lists are built (and subsequently dumped) in the
74 * order in which the names are encountered during the namespace load;
76 * All namespace searching is linear in this implementation, but
77 * could be easily modified to support any improved search
78 * algorithm. However, the linear search was chosen for simplicity
79 * and because the trees are small and the other interpreter
80 * execution overhead is relatively high.
82 ******************************************************************************/
85 acpi_ns_search_node(u32 target_name
,
86 struct acpi_namespace_node
*node
,
87 acpi_object_type type
,
88 struct acpi_namespace_node
**return_node
)
90 struct acpi_namespace_node
*next_node
;
92 ACPI_FUNCTION_TRACE("ns_search_node");
94 #ifdef ACPI_DEBUG_OUTPUT
95 if (ACPI_LV_NAMES
& acpi_dbg_level
) {
98 scope_name
= acpi_ns_get_external_pathname(node
);
100 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
101 "Searching %s (%p) For [%4.4s] (%s)\n",
102 scope_name
, node
, ACPI_CAST_PTR(char,
104 acpi_ut_get_type_name(type
)));
106 ACPI_FREE(scope_name
);
112 * Search for name at this namespace level, which is to say that we
113 * must search for the name among the children of this object
115 next_node
= node
->child
;
118 /* Check for match against the name */
120 if (next_node
->name
.integer
== target_name
) {
122 /* Resolve a control method alias if any */
124 if (acpi_ns_get_type(next_node
) ==
125 ACPI_TYPE_LOCAL_METHOD_ALIAS
) {
127 ACPI_CAST_PTR(struct acpi_namespace_node
,
131 /* Found matching entry */
133 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
134 "Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n",
135 ACPI_CAST_PTR(char, &target_name
),
136 acpi_ut_get_type_name(next_node
->
139 acpi_ut_get_node_name(node
), node
));
141 *return_node
= next_node
;
142 return_ACPI_STATUS(AE_OK
);
146 * The last entry in the list points back to the parent,
147 * so a flag is used to indicate the end-of-list
149 if (next_node
->flags
& ANOBJ_END_OF_PEER_LIST
) {
151 /* Searched entire list, we are done */
156 /* Didn't match name, move on to the next peer object */
158 next_node
= next_node
->peer
;
161 /* Searched entire namespace level, not found */
163 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
164 "Name [%4.4s] (%s) not found in search in scope [%4.4s] %p first child %p\n",
165 ACPI_CAST_PTR(char, &target_name
),
166 acpi_ut_get_type_name(type
),
167 acpi_ut_get_node_name(node
), node
, node
->child
));
169 return_ACPI_STATUS(AE_NOT_FOUND
);
172 /*******************************************************************************
174 * FUNCTION: acpi_ns_search_parent_tree
176 * PARAMETERS: target_name - Ascii ACPI name to search for
177 * Node - Starting node where search will begin
178 * Type - Object type to match
179 * return_node - Where the matched Node is returned
183 * DESCRIPTION: Called when a name has not been found in the current namespace
184 * level. Before adding it or giving up, ACPI scope rules require
185 * searching enclosing scopes in cases identified by acpi_ns_local().
187 * "A name is located by finding the matching name in the current
188 * name space, and then in the parent name space. If the parent
189 * name space does not contain the name, the search continues
190 * recursively until either the name is found or the name space
191 * does not have a parent (the root of the name space). This
192 * indicates that the name is not found" (From ACPI Specification,
195 ******************************************************************************/
198 acpi_ns_search_parent_tree(u32 target_name
,
199 struct acpi_namespace_node
*node
,
200 acpi_object_type type
,
201 struct acpi_namespace_node
**return_node
)
204 struct acpi_namespace_node
*parent_node
;
206 ACPI_FUNCTION_TRACE("ns_search_parent_tree");
208 parent_node
= acpi_ns_get_parent_node(node
);
211 * If there is no parent (i.e., we are at the root) or type is "local",
212 * we won't be searching the parent tree.
215 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
, "[%4.4s] has no parent\n",
216 ACPI_CAST_PTR(char, &target_name
)));
217 return_ACPI_STATUS(AE_NOT_FOUND
);
220 if (acpi_ns_local(type
)) {
221 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
222 "[%4.4s] type [%s] must be local to this scope (no parent search)\n",
223 ACPI_CAST_PTR(char, &target_name
),
224 acpi_ut_get_type_name(type
)));
225 return_ACPI_STATUS(AE_NOT_FOUND
);
228 /* Search the parent tree */
230 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
231 "Searching parent [%4.4s] for [%4.4s]\n",
232 acpi_ut_get_node_name(parent_node
),
233 ACPI_CAST_PTR(char, &target_name
)));
236 * Search parents until target is found or we have backed up to the root
238 while (parent_node
) {
240 * Search parent scope. Use TYPE_ANY because we don't care about the
241 * object type at this point, we only care about the existence of
242 * the actual name we are searching for. Typechecking comes later.
244 status
= acpi_ns_search_node(target_name
, parent_node
,
245 ACPI_TYPE_ANY
, return_node
);
246 if (ACPI_SUCCESS(status
)) {
247 return_ACPI_STATUS(status
);
250 /* Not found here, go up another level (until we reach the root) */
252 parent_node
= acpi_ns_get_parent_node(parent_node
);
255 /* Not found in parent tree */
257 return_ACPI_STATUS(AE_NOT_FOUND
);
260 /*******************************************************************************
262 * FUNCTION: acpi_ns_search_and_enter
264 * PARAMETERS: target_name - Ascii ACPI name to search for (4 chars)
265 * walk_state - Current state of the walk
266 * Node - Starting node where search will begin
267 * interpreter_mode - Add names only in ACPI_MODE_LOAD_PASS_x.
268 * Otherwise,search only.
269 * Type - Object type to match
270 * Flags - Flags describing the search restrictions
271 * return_node - Where the Node is returned
275 * DESCRIPTION: Search for a name segment in a single namespace level,
276 * optionally adding it if it is not found. If the passed
277 * Type is not Any and the type previously stored in the
278 * entry was Any (i.e. unknown), update the stored type.
280 * In ACPI_IMODE_EXECUTE, search only.
281 * In other modes, search and add if not found.
283 ******************************************************************************/
286 acpi_ns_search_and_enter(u32 target_name
,
287 struct acpi_walk_state
*walk_state
,
288 struct acpi_namespace_node
*node
,
289 acpi_interpreter_mode interpreter_mode
,
290 acpi_object_type type
,
291 u32 flags
, struct acpi_namespace_node
**return_node
)
294 struct acpi_namespace_node
*new_node
;
296 ACPI_FUNCTION_TRACE("ns_search_and_enter");
298 /* Parameter validation */
300 if (!node
|| !target_name
|| !return_node
) {
302 "Null param: Node %p Name %X return_node %p",
303 node
, target_name
, return_node
));
304 return_ACPI_STATUS(AE_BAD_PARAMETER
);
308 * Name must consist of valid ACPI characters. We will repair the name if
309 * necessary because we don't want to abort because of this, but we want
310 * all namespace names to be printable. A warning message is appropriate.
312 * This issue came up because there are in fact machines that exhibit
313 * this problem, and we want to be able to enable ACPI support for them,
314 * even though there are a few bad names.
316 if (!acpi_ut_valid_acpi_name(target_name
)) {
317 target_name
= acpi_ut_repair_name(target_name
);
319 /* Report warning only if in strict mode or debug mode */
321 if (!acpi_gbl_enable_interpreter_slack
) {
322 ACPI_WARNING((AE_INFO
,
323 "Found bad character(s) in name, repaired: [%4.4s]\n",
324 ACPI_CAST_PTR(char, &target_name
)));
326 ACPI_DEBUG_PRINT((ACPI_DB_WARN
,
327 "Found bad character(s) in name, repaired: [%4.4s]\n",
328 ACPI_CAST_PTR(char, &target_name
)));
332 /* Try to find the name in the namespace level specified by the caller */
334 *return_node
= ACPI_ENTRY_NOT_FOUND
;
335 status
= acpi_ns_search_node(target_name
, node
, type
, return_node
);
336 if (status
!= AE_NOT_FOUND
) {
338 * If we found it AND the request specifies that a find is an error,
341 if ((status
== AE_OK
) && (flags
& ACPI_NS_ERROR_IF_FOUND
)) {
342 status
= AE_ALREADY_EXISTS
;
345 /* Either found it or there was an error: finished either way */
347 return_ACPI_STATUS(status
);
351 * The name was not found. If we are NOT performing the first pass
352 * (name entry) of loading the namespace, search the parent tree (all the
353 * way to the root if necessary.) We don't want to perform the parent
354 * search when the namespace is actually being loaded. We want to perform
355 * the search when namespace references are being resolved (load pass 2)
356 * and during the execution phase.
358 if ((interpreter_mode
!= ACPI_IMODE_LOAD_PASS1
) &&
359 (flags
& ACPI_NS_SEARCH_PARENT
)) {
361 * Not found at this level - search parent tree according to the
365 acpi_ns_search_parent_tree(target_name
, node
, type
,
367 if (ACPI_SUCCESS(status
)) {
368 return_ACPI_STATUS(status
);
372 /* In execute mode, just search, never add names. Exit now */
374 if (interpreter_mode
== ACPI_IMODE_EXECUTE
) {
375 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
376 "%4.4s Not found in %p [Not adding]\n",
377 ACPI_CAST_PTR(char, &target_name
), node
));
379 return_ACPI_STATUS(AE_NOT_FOUND
);
382 /* Create the new named object */
384 new_node
= acpi_ns_create_node(target_name
);
386 return_ACPI_STATUS(AE_NO_MEMORY
);
389 /* Install the new object into the parent's list of children */
391 acpi_ns_install_node(walk_state
, node
, new_node
, type
);
392 *return_node
= new_node
;
393 return_ACPI_STATUS(AE_OK
);