1 /*******************************************************************************
3 * Module Name: nssearch - Namespace search
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2016, Intel Corp.
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20 * including a substantially similar Disclaimer requirement for further
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23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
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48 #ifdef ACPI_ASL_COMPILER
52 #define _COMPONENT ACPI_NAMESPACE
53 ACPI_MODULE_NAME ("nssearch")
55 /* Local prototypes */
58 AcpiNsSearchParentTree (
60 ACPI_NAMESPACE_NODE
*Node
,
61 ACPI_OBJECT_TYPE Type
,
62 ACPI_NAMESPACE_NODE
**ReturnNode
);
65 /*******************************************************************************
67 * FUNCTION: AcpiNsSearchOneScope
69 * PARAMETERS: TargetName - Ascii ACPI name to search for
70 * ParentNode - Starting node where search will begin
71 * Type - Object type to match
72 * ReturnNode - Where the matched Named obj is returned
76 * DESCRIPTION: Search a single level of the namespace. Performs a
77 * simple search of the specified level, and does not add
78 * entries or search parents.
81 * Named object lists are built (and subsequently dumped) in the
82 * order in which the names are encountered during the namespace load;
84 * All namespace searching is linear in this implementation, but
85 * could be easily modified to support any improved search
86 * algorithm. However, the linear search was chosen for simplicity
87 * and because the trees are small and the other interpreter
88 * execution overhead is relatively high.
90 * Note: CPU execution analysis has shown that the AML interpreter spends
91 * a very small percentage of its time searching the namespace. Therefore,
92 * the linear search seems to be sufficient, as there would seem to be
93 * little value in improving the search.
95 ******************************************************************************/
98 AcpiNsSearchOneScope (
100 ACPI_NAMESPACE_NODE
*ParentNode
,
101 ACPI_OBJECT_TYPE Type
,
102 ACPI_NAMESPACE_NODE
**ReturnNode
)
104 ACPI_NAMESPACE_NODE
*Node
;
107 ACPI_FUNCTION_TRACE (NsSearchOneScope
);
110 #ifdef ACPI_DEBUG_OUTPUT
111 if (ACPI_LV_NAMES
& AcpiDbgLevel
)
115 ScopeName
= AcpiNsGetNormalizedPathname (ParentNode
, TRUE
);
118 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
119 "Searching %s (%p) For [%4.4s] (%s)\n",
120 ScopeName
, ParentNode
, ACPI_CAST_PTR (char, &TargetName
),
121 AcpiUtGetTypeName (Type
)));
123 ACPI_FREE (ScopeName
);
129 * Search for name at this namespace level, which is to say that we
130 * must search for the name among the children of this object
132 Node
= ParentNode
->Child
;
135 /* Check for match against the name */
137 if (Node
->Name
.Integer
== TargetName
)
139 /* Resolve a control method alias if any */
141 if (AcpiNsGetType (Node
) == ACPI_TYPE_LOCAL_METHOD_ALIAS
)
143 Node
= ACPI_CAST_PTR (ACPI_NAMESPACE_NODE
, Node
->Object
);
146 /* Found matching entry */
148 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
149 "Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n",
150 ACPI_CAST_PTR (char, &TargetName
),
151 AcpiUtGetTypeName (Node
->Type
),
152 Node
, AcpiUtGetNodeName (ParentNode
), ParentNode
));
155 return_ACPI_STATUS (AE_OK
);
158 /* Didn't match name, move on to the next peer object */
163 /* Searched entire namespace level, not found */
165 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
166 "Name [%4.4s] (%s) not found in search in scope [%4.4s] "
167 "%p first child %p\n",
168 ACPI_CAST_PTR (char, &TargetName
), AcpiUtGetTypeName (Type
),
169 AcpiUtGetNodeName (ParentNode
), ParentNode
, ParentNode
->Child
));
171 return_ACPI_STATUS (AE_NOT_FOUND
);
175 /*******************************************************************************
177 * FUNCTION: AcpiNsSearchParentTree
179 * PARAMETERS: TargetName - Ascii ACPI name to search for
180 * Node - Starting node where search will begin
181 * Type - Object type to match
182 * ReturnNode - Where the matched Node is returned
186 * DESCRIPTION: Called when a name has not been found in the current namespace
187 * level. Before adding it or giving up, ACPI scope rules require
188 * searching enclosing scopes in cases identified by AcpiNsLocal().
190 * "A name is located by finding the matching name in the current
191 * name space, and then in the parent name space. If the parent
192 * name space does not contain the name, the search continues
193 * recursively until either the name is found or the name space
194 * does not have a parent (the root of the name space). This
195 * indicates that the name is not found" (From ACPI Specification,
198 ******************************************************************************/
201 AcpiNsSearchParentTree (
203 ACPI_NAMESPACE_NODE
*Node
,
204 ACPI_OBJECT_TYPE Type
,
205 ACPI_NAMESPACE_NODE
**ReturnNode
)
208 ACPI_NAMESPACE_NODE
*ParentNode
;
211 ACPI_FUNCTION_TRACE (NsSearchParentTree
);
214 ParentNode
= Node
->Parent
;
217 * If there is no parent (i.e., we are at the root) or type is "local",
218 * we won't be searching the parent tree.
222 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
, "[%4.4s] has no parent\n",
223 ACPI_CAST_PTR (char, &TargetName
)));
224 return_ACPI_STATUS (AE_NOT_FOUND
);
227 if (AcpiNsLocal (Type
))
229 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
230 "[%4.4s] type [%s] must be local to this scope (no parent search)\n",
231 ACPI_CAST_PTR (char, &TargetName
), AcpiUtGetTypeName (Type
)));
232 return_ACPI_STATUS (AE_NOT_FOUND
);
235 /* Search the parent tree */
237 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
238 "Searching parent [%4.4s] for [%4.4s]\n",
239 AcpiUtGetNodeName (ParentNode
), ACPI_CAST_PTR (char, &TargetName
)));
241 /* Search parents until target is found or we have backed up to the root */
246 * Search parent scope. Use TYPE_ANY because we don't care about the
247 * object type at this point, we only care about the existence of
248 * the actual name we are searching for. Typechecking comes later.
250 Status
= AcpiNsSearchOneScope (
251 TargetName
, ParentNode
, ACPI_TYPE_ANY
, ReturnNode
);
252 if (ACPI_SUCCESS (Status
))
254 return_ACPI_STATUS (Status
);
257 /* Not found here, go up another level (until we reach the root) */
259 ParentNode
= ParentNode
->Parent
;
262 /* Not found in parent tree */
264 return_ACPI_STATUS (AE_NOT_FOUND
);
268 /*******************************************************************************
270 * FUNCTION: AcpiNsSearchAndEnter
272 * PARAMETERS: TargetName - Ascii ACPI name to search for (4 chars)
273 * WalkState - Current state of the walk
274 * Node - Starting node where search will begin
275 * InterpreterMode - 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
279 * ReturnNode - Where the Node is returned
283 * DESCRIPTION: Search for a name segment in a single namespace level,
284 * optionally adding it if it is not found. If the passed
285 * Type is not Any and the type previously stored in the
286 * entry was Any (i.e. unknown), update the stored type.
288 * In ACPI_IMODE_EXECUTE, search only.
289 * In other modes, search and add if not found.
291 ******************************************************************************/
294 AcpiNsSearchAndEnter (
296 ACPI_WALK_STATE
*WalkState
,
297 ACPI_NAMESPACE_NODE
*Node
,
298 ACPI_INTERPRETER_MODE InterpreterMode
,
299 ACPI_OBJECT_TYPE Type
,
301 ACPI_NAMESPACE_NODE
**ReturnNode
)
304 ACPI_NAMESPACE_NODE
*NewNode
;
307 ACPI_FUNCTION_TRACE (NsSearchAndEnter
);
310 /* Parameter validation */
312 if (!Node
|| !TargetName
|| !ReturnNode
)
314 ACPI_ERROR ((AE_INFO
,
315 "Null parameter: Node %p Name 0x%X ReturnNode %p",
316 Node
, TargetName
, ReturnNode
));
317 return_ACPI_STATUS (AE_BAD_PARAMETER
);
321 * Name must consist of valid ACPI characters. We will repair the name if
322 * necessary because we don't want to abort because of this, but we want
323 * all namespace names to be printable. A warning message is appropriate.
325 * This issue came up because there are in fact machines that exhibit
326 * this problem, and we want to be able to enable ACPI support for them,
327 * even though there are a few bad names.
329 AcpiUtRepairName (ACPI_CAST_PTR (char, &TargetName
));
331 /* Try to find the name in the namespace level specified by the caller */
333 *ReturnNode
= ACPI_ENTRY_NOT_FOUND
;
334 Status
= AcpiNsSearchOneScope (TargetName
, Node
, Type
, ReturnNode
);
335 if (Status
!= AE_NOT_FOUND
)
338 * If we found it AND the request specifies that a find is an error,
343 /* The node was found in the namespace */
346 * If the namespace override feature is enabled for this node,
347 * delete any existing attached sub-object and make the node
348 * look like a new node that is owned by the override table.
350 if (Flags
& ACPI_NS_OVERRIDE_IF_FOUND
)
352 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
353 "Namespace override: %4.4s pass %u type %X Owner %X\n",
354 ACPI_CAST_PTR(char, &TargetName
), InterpreterMode
,
355 (*ReturnNode
)->Type
, WalkState
->OwnerId
));
357 AcpiNsDeleteChildren (*ReturnNode
);
358 if (AcpiGbl_RuntimeNamespaceOverride
)
360 AcpiUtRemoveReference ((*ReturnNode
)->Object
);
361 (*ReturnNode
)->Object
= NULL
;
362 (*ReturnNode
)->OwnerId
= WalkState
->OwnerId
;
366 AcpiNsRemoveNode (*ReturnNode
);
367 *ReturnNode
= ACPI_ENTRY_NOT_FOUND
;
371 /* Return an error if we don't expect to find the object */
373 else if (Flags
& ACPI_NS_ERROR_IF_FOUND
)
375 Status
= AE_ALREADY_EXISTS
;
379 #ifdef ACPI_ASL_COMPILER
380 if (*ReturnNode
&& (*ReturnNode
)->Type
== ACPI_TYPE_ANY
)
382 (*ReturnNode
)->Flags
|= ANOBJ_IS_EXTERNAL
;
386 /* Either found it or there was an error: finished either way */
388 return_ACPI_STATUS (Status
);
392 * The name was not found. If we are NOT performing the first pass
393 * (name entry) of loading the namespace, search the parent tree (all the
394 * way to the root if necessary.) We don't want to perform the parent
395 * search when the namespace is actually being loaded. We want to perform
396 * the search when namespace references are being resolved (load pass 2)
397 * and during the execution phase.
399 if ((InterpreterMode
!= ACPI_IMODE_LOAD_PASS1
) &&
400 (Flags
& ACPI_NS_SEARCH_PARENT
))
403 * Not found at this level - search parent tree according to the
406 Status
= AcpiNsSearchParentTree (TargetName
, Node
, Type
, ReturnNode
);
407 if (ACPI_SUCCESS (Status
))
409 return_ACPI_STATUS (Status
);
413 /* In execute mode, just search, never add names. Exit now */
415 if (InterpreterMode
== ACPI_IMODE_EXECUTE
)
417 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
418 "%4.4s Not found in %p [Not adding]\n",
419 ACPI_CAST_PTR (char, &TargetName
), Node
));
421 return_ACPI_STATUS (AE_NOT_FOUND
);
424 /* Create the new named object */
426 NewNode
= AcpiNsCreateNode (TargetName
);
429 return_ACPI_STATUS (AE_NO_MEMORY
);
432 #ifdef ACPI_ASL_COMPILER
434 /* Node is an object defined by an External() statement */
436 if (Flags
& ACPI_NS_EXTERNAL
||
437 (WalkState
&& WalkState
->Opcode
== AML_SCOPE_OP
))
439 NewNode
->Flags
|= ANOBJ_IS_EXTERNAL
;
443 if (Flags
& ACPI_NS_TEMPORARY
)
445 NewNode
->Flags
|= ANOBJ_TEMPORARY
;
448 /* Install the new object into the parent's list of children */
450 AcpiNsInstallNode (WalkState
, Node
, NewNode
, Type
);
451 *ReturnNode
= NewNode
;
452 return_ACPI_STATUS (AE_OK
);