1 /*******************************************************************************
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2013, 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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44 #define __NSACCESS_C__
53 #define _COMPONENT ACPI_NAMESPACE
54 ACPI_MODULE_NAME ("nsaccess")
57 /*******************************************************************************
59 * FUNCTION: AcpiNsRootInitialize
65 * DESCRIPTION: Allocate and initialize the default root named objects
67 * MUTEX: Locks namespace for entire execution
69 ******************************************************************************/
72 AcpiNsRootInitialize (
76 const ACPI_PREDEFINED_NAMES
*InitVal
= NULL
;
77 ACPI_NAMESPACE_NODE
*NewNode
;
78 ACPI_OPERAND_OBJECT
*ObjDesc
;
79 ACPI_STRING Val
= NULL
;
82 ACPI_FUNCTION_TRACE (NsRootInitialize
);
85 Status
= AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE
);
86 if (ACPI_FAILURE (Status
))
88 return_ACPI_STATUS (Status
);
92 * The global root ptr is initially NULL, so a non-NULL value indicates
93 * that AcpiNsRootInitialize() has already been called; just return.
102 * Tell the rest of the subsystem that the root is initialized
103 * (This is OK because the namespace is locked)
105 AcpiGbl_RootNode
= &AcpiGbl_RootNodeStruct
;
107 /* Enter the pre-defined names in the name table */
109 ACPI_DEBUG_PRINT ((ACPI_DB_INFO
,
110 "Entering predefined entries into namespace\n"));
112 for (InitVal
= AcpiGbl_PreDefinedNames
; InitVal
->Name
; InitVal
++)
114 /* _OSI is optional for now, will be permanent later */
116 if (!ACPI_STRCMP (InitVal
->Name
, "_OSI") && !AcpiGbl_CreateOsiMethod
)
121 Status
= AcpiNsLookup (NULL
, InitVal
->Name
, InitVal
->Type
,
122 ACPI_IMODE_LOAD_PASS2
, ACPI_NS_NO_UPSEARCH
,
124 if (ACPI_FAILURE (Status
))
126 ACPI_EXCEPTION ((AE_INFO
, Status
,
127 "Could not create predefined name %s",
133 * Name entered successfully. If entry in PreDefinedNames[] specifies
134 * an initial value, create the initial value.
138 Status
= AcpiOsPredefinedOverride (InitVal
, &Val
);
139 if (ACPI_FAILURE (Status
))
141 ACPI_ERROR ((AE_INFO
,
142 "Could not override predefined %s",
152 * Entry requests an initial value, allocate a
155 ObjDesc
= AcpiUtCreateInternalObject (InitVal
->Type
);
158 Status
= AE_NO_MEMORY
;
163 * Convert value string from table entry to
164 * internal representation. Only types actually
165 * used for initial values are implemented here.
167 switch (InitVal
->Type
)
169 case ACPI_TYPE_METHOD
:
171 ObjDesc
->Method
.ParamCount
= (UINT8
) ACPI_TO_INTEGER (Val
);
172 ObjDesc
->Common
.Flags
|= AOPOBJ_DATA_VALID
;
174 #if defined (ACPI_ASL_COMPILER)
176 /* Save the parameter count for the iASL compiler */
178 NewNode
->Value
= ObjDesc
->Method
.ParamCount
;
180 /* Mark this as a very SPECIAL method */
182 ObjDesc
->Method
.InfoFlags
= ACPI_METHOD_INTERNAL_ONLY
;
183 ObjDesc
->Method
.Dispatch
.Implementation
= AcpiUtOsiImplementation
;
187 case ACPI_TYPE_INTEGER
:
189 ObjDesc
->Integer
.Value
= ACPI_TO_INTEGER (Val
);
192 case ACPI_TYPE_STRING
:
194 /* Build an object around the static string */
196 ObjDesc
->String
.Length
= (UINT32
) ACPI_STRLEN (Val
);
197 ObjDesc
->String
.Pointer
= Val
;
198 ObjDesc
->Common
.Flags
|= AOPOBJ_STATIC_POINTER
;
201 case ACPI_TYPE_MUTEX
:
203 ObjDesc
->Mutex
.Node
= NewNode
;
204 ObjDesc
->Mutex
.SyncLevel
= (UINT8
) (ACPI_TO_INTEGER (Val
) - 1);
208 Status
= AcpiOsCreateMutex (&ObjDesc
->Mutex
.OsMutex
);
209 if (ACPI_FAILURE (Status
))
211 AcpiUtRemoveReference (ObjDesc
);
215 /* Special case for ACPI Global Lock */
217 if (ACPI_STRCMP (InitVal
->Name
, "_GL_") == 0)
219 AcpiGbl_GlobalLockMutex
= ObjDesc
;
221 /* Create additional counting semaphore for global lock */
223 Status
= AcpiOsCreateSemaphore (
224 1, 0, &AcpiGbl_GlobalLockSemaphore
);
225 if (ACPI_FAILURE (Status
))
227 AcpiUtRemoveReference (ObjDesc
);
235 ACPI_ERROR ((AE_INFO
, "Unsupported initial type value 0x%X",
237 AcpiUtRemoveReference (ObjDesc
);
242 /* Store pointer to value descriptor in the Node */
244 Status
= AcpiNsAttachObject (NewNode
, ObjDesc
,
245 ObjDesc
->Common
.Type
);
247 /* Remove local reference to the object */
249 AcpiUtRemoveReference (ObjDesc
);
255 (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE
);
257 /* Save a handle to "_GPE", it is always present */
259 if (ACPI_SUCCESS (Status
))
261 Status
= AcpiNsGetNode (NULL
, "\\_GPE", ACPI_NS_NO_UPSEARCH
,
262 &AcpiGbl_FadtGpeDevice
);
265 return_ACPI_STATUS (Status
);
269 /*******************************************************************************
271 * FUNCTION: AcpiNsLookup
273 * PARAMETERS: ScopeInfo - Current scope info block
274 * Pathname - Search pathname, in internal format
275 * (as represented in the AML stream)
276 * Type - Type associated with name
277 * InterpreterMode - IMODE_LOAD_PASS2 => add name if not found
278 * Flags - Flags describing the search restrictions
279 * WalkState - Current state of the walk
280 * ReturnNode - Where the Node is placed (if found
281 * or created successfully)
285 * DESCRIPTION: Find or enter the passed name in the name space.
286 * Log an error if name not found in Exec mode.
288 * MUTEX: Assumes namespace is locked.
290 ******************************************************************************/
294 ACPI_GENERIC_STATE
*ScopeInfo
,
296 ACPI_OBJECT_TYPE Type
,
297 ACPI_INTERPRETER_MODE InterpreterMode
,
299 ACPI_WALK_STATE
*WalkState
,
300 ACPI_NAMESPACE_NODE
**ReturnNode
)
303 char *Path
= Pathname
;
304 ACPI_NAMESPACE_NODE
*PrefixNode
;
305 ACPI_NAMESPACE_NODE
*CurrentNode
= NULL
;
306 ACPI_NAMESPACE_NODE
*ThisNode
= NULL
;
309 ACPI_NAME SimpleName
;
310 ACPI_OBJECT_TYPE TypeToCheckFor
;
311 ACPI_OBJECT_TYPE ThisSearchType
;
312 UINT32 SearchParentFlag
= ACPI_NS_SEARCH_PARENT
;
316 ACPI_FUNCTION_TRACE (NsLookup
);
321 return_ACPI_STATUS (AE_BAD_PARAMETER
);
324 LocalFlags
= Flags
& ~(ACPI_NS_ERROR_IF_FOUND
| ACPI_NS_SEARCH_PARENT
);
325 *ReturnNode
= ACPI_ENTRY_NOT_FOUND
;
326 AcpiGbl_NsLookupCount
++;
328 if (!AcpiGbl_RootNode
)
330 return_ACPI_STATUS (AE_NO_NAMESPACE
);
333 /* Get the prefix scope. A null scope means use the root scope */
336 (!ScopeInfo
->Scope
.Node
))
338 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
339 "Null scope prefix, using root node (%p)\n",
342 PrefixNode
= AcpiGbl_RootNode
;
346 PrefixNode
= ScopeInfo
->Scope
.Node
;
347 if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode
) != ACPI_DESC_TYPE_NAMED
)
349 ACPI_ERROR ((AE_INFO
, "%p is not a namespace node [%s]",
350 PrefixNode
, AcpiUtGetDescriptorName (PrefixNode
)));
351 return_ACPI_STATUS (AE_AML_INTERNAL
);
354 if (!(Flags
& ACPI_NS_PREFIX_IS_SCOPE
))
357 * This node might not be a actual "scope" node (such as a
358 * Device/Method, etc.) It could be a Package or other object
359 * node. Backup up the tree to find the containing scope node.
361 while (!AcpiNsOpensScope (PrefixNode
->Type
) &&
362 PrefixNode
->Type
!= ACPI_TYPE_ANY
)
364 PrefixNode
= PrefixNode
->Parent
;
369 /* Save type. TBD: may be no longer necessary */
371 TypeToCheckFor
= Type
;
374 * Begin examination of the actual pathname
378 /* A Null NamePath is allowed and refers to the root */
381 ThisNode
= AcpiGbl_RootNode
;
384 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
385 "Null Pathname (Zero segments), Flags=%X\n", Flags
));
390 * Name pointer is valid (and must be in internal name format)
392 * Check for scope prefixes:
394 * As represented in the AML stream, a namepath consists of an
395 * optional scope prefix followed by a name segment part.
397 * If present, the scope prefix is either a Root Prefix (in
398 * which case the name is fully qualified), or one or more
399 * Parent Prefixes (in which case the name's scope is relative
400 * to the current scope).
402 if (*Path
== (UINT8
) AML_ROOT_PREFIX
)
404 /* Pathname is fully qualified, start from the root */
406 ThisNode
= AcpiGbl_RootNode
;
407 SearchParentFlag
= ACPI_NS_NO_UPSEARCH
;
409 /* Point to name segment part */
413 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
414 "Path is absolute from root [%p]\n", ThisNode
));
418 /* Pathname is relative to current scope, start there */
420 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
421 "Searching relative to prefix scope [%4.4s] (%p)\n",
422 AcpiUtGetNodeName (PrefixNode
), PrefixNode
));
425 * Handle multiple Parent Prefixes (carat) by just getting
426 * the parent node for each prefix instance.
428 ThisNode
= PrefixNode
;
430 while (*Path
== (UINT8
) AML_PARENT_PREFIX
)
432 /* Name is fully qualified, no search rules apply */
434 SearchParentFlag
= ACPI_NS_NO_UPSEARCH
;
437 * Point past this prefix to the name segment
438 * part or the next Parent Prefix
442 /* Backup to the parent node */
445 ThisNode
= ThisNode
->Parent
;
448 /* Current scope has no parent scope */
450 ACPI_ERROR ((AE_INFO
,
451 "%s: Path has too many parent prefixes (^) "
452 "- reached beyond root node", Pathname
));
453 return_ACPI_STATUS (AE_NOT_FOUND
);
457 if (SearchParentFlag
== ACPI_NS_NO_UPSEARCH
)
459 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
460 "Search scope is [%4.4s], path has %u carat(s)\n",
461 AcpiUtGetNodeName (ThisNode
), NumCarats
));
466 * Determine the number of ACPI name segments in this pathname.
468 * The segment part consists of either:
469 * - A Null name segment (0)
470 * - A DualNamePrefix followed by two 4-byte name segments
471 * - A MultiNamePrefix followed by a byte indicating the
472 * number of segments and the segments themselves.
473 * - A single 4-byte name segment
475 * Examine the name prefix opcode, if any, to determine the number of
482 * Null name after a root or parent prefixes. We already
483 * have the correct target node and there are no name segments.
486 Type
= ThisNode
->Type
;
488 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
489 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
493 case AML_DUAL_NAME_PREFIX
:
495 /* More than one NameSeg, search rules do not apply */
497 SearchParentFlag
= ACPI_NS_NO_UPSEARCH
;
499 /* Two segments, point to first name segment */
504 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
505 "Dual Pathname (2 segments, Flags=%X)\n", Flags
));
508 case AML_MULTI_NAME_PREFIX_OP
:
510 /* More than one NameSeg, search rules do not apply */
512 SearchParentFlag
= ACPI_NS_NO_UPSEARCH
;
514 /* Extract segment count, point to first name segment */
517 NumSegments
= (UINT32
) (UINT8
) *Path
;
520 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
521 "Multi Pathname (%u Segments, Flags=%X)\n",
522 NumSegments
, Flags
));
527 * Not a Null name, no Dual or Multi prefix, hence there is
528 * only one name segment and Pathname is already pointing to it.
532 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
533 "Simple Pathname (1 segment, Flags=%X)\n", Flags
));
537 ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments
, Path
));
542 * Search namespace for each segment of the name. Loop through and
543 * verify (or add to the namespace) each name segment.
545 * The object type is significant only at the last name
546 * segment. (We don't care about the types along the path, only
547 * the type of the final target object.)
549 ThisSearchType
= ACPI_TYPE_ANY
;
550 CurrentNode
= ThisNode
;
551 while (NumSegments
&& CurrentNode
)
556 /* This is the last segment, enable typechecking */
558 ThisSearchType
= Type
;
561 * Only allow automatic parent search (search rules) if the caller
562 * requested it AND we have a single, non-fully-qualified NameSeg
564 if ((SearchParentFlag
!= ACPI_NS_NO_UPSEARCH
) &&
565 (Flags
& ACPI_NS_SEARCH_PARENT
))
567 LocalFlags
|= ACPI_NS_SEARCH_PARENT
;
570 /* Set error flag according to caller */
572 if (Flags
& ACPI_NS_ERROR_IF_FOUND
)
574 LocalFlags
|= ACPI_NS_ERROR_IF_FOUND
;
578 /* Extract one ACPI name from the front of the pathname */
580 ACPI_MOVE_32_TO_32 (&SimpleName
, Path
);
582 /* Try to find the single (4 character) ACPI name */
584 Status
= AcpiNsSearchAndEnter (SimpleName
, WalkState
, CurrentNode
,
585 InterpreterMode
, ThisSearchType
, LocalFlags
, &ThisNode
);
586 if (ACPI_FAILURE (Status
))
588 if (Status
== AE_NOT_FOUND
)
590 /* Name not found in ACPI namespace */
592 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
593 "Name [%4.4s] not found in scope [%4.4s] %p\n",
594 (char *) &SimpleName
, (char *) &CurrentNode
->Name
,
598 *ReturnNode
= ThisNode
;
599 return_ACPI_STATUS (Status
);
602 /* More segments to follow? */
607 * If we have an alias to an object that opens a scope (such as a
608 * device or processor), we need to dereference the alias here so
609 * that we can access any children of the original node (via the
610 * remaining segments).
612 if (ThisNode
->Type
== ACPI_TYPE_LOCAL_ALIAS
)
614 if (!ThisNode
->Object
)
616 return_ACPI_STATUS (AE_NOT_EXIST
);
619 if (AcpiNsOpensScope (((ACPI_NAMESPACE_NODE
*)
620 ThisNode
->Object
)->Type
))
622 ThisNode
= (ACPI_NAMESPACE_NODE
*) ThisNode
->Object
;
627 /* Special handling for the last segment (NumSegments == 0) */
632 * Sanity typecheck of the target object:
634 * If 1) This is the last segment (NumSegments == 0)
635 * 2) And we are looking for a specific type
636 * (Not checking for TYPE_ANY)
637 * 3) Which is not an alias
638 * 4) Which is not a local type (TYPE_SCOPE)
639 * 5) And the type of target object is known (not TYPE_ANY)
640 * 6) And target object does not match what we are looking for
642 * Then we have a type mismatch. Just warn and ignore it.
644 if ((TypeToCheckFor
!= ACPI_TYPE_ANY
) &&
645 (TypeToCheckFor
!= ACPI_TYPE_LOCAL_ALIAS
) &&
646 (TypeToCheckFor
!= ACPI_TYPE_LOCAL_METHOD_ALIAS
) &&
647 (TypeToCheckFor
!= ACPI_TYPE_LOCAL_SCOPE
) &&
648 (ThisNode
->Type
!= ACPI_TYPE_ANY
) &&
649 (ThisNode
->Type
!= TypeToCheckFor
))
651 /* Complain about a type mismatch */
653 ACPI_WARNING ((AE_INFO
,
654 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
655 ACPI_CAST_PTR (char, &SimpleName
),
656 AcpiUtGetTypeName (ThisNode
->Type
),
657 AcpiUtGetTypeName (TypeToCheckFor
)));
661 * If this is the last name segment and we are not looking for a
662 * specific type, but the type of found object is known, use that
663 * type to (later) see if it opens a scope.
665 if (Type
== ACPI_TYPE_ANY
)
667 Type
= ThisNode
->Type
;
671 /* Point to next name segment and make this node current */
673 Path
+= ACPI_NAME_SIZE
;
674 CurrentNode
= ThisNode
;
677 /* Always check if we need to open a new scope */
679 if (!(Flags
& ACPI_NS_DONT_OPEN_SCOPE
) && (WalkState
))
682 * If entry is a type which opens a scope, push the new scope on the
685 if (AcpiNsOpensScope (Type
))
687 Status
= AcpiDsScopeStackPush (ThisNode
, Type
, WalkState
);
688 if (ACPI_FAILURE (Status
))
690 return_ACPI_STATUS (Status
);
695 *ReturnNode
= ThisNode
;
696 return_ACPI_STATUS (AE_OK
);