1 /*******************************************************************************
2 *
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
4 *
5 ******************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2011, Intel Corp.
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
44 #define __NSACCESS_C__
45
46 #include "acpi.h"
47 #include "accommon.h"
48 #include "amlcode.h"
49 #include "acnamesp.h"
50 #include "acdispat.h"
51
52
53 #define _COMPONENT ACPI_NAMESPACE
54 ACPI_MODULE_NAME ("nsaccess")
55
56
57 /*******************************************************************************
58 *
59 * FUNCTION: AcpiNsRootInitialize
60 *
61 * PARAMETERS: None
62 *
63 * RETURN: Status
64 *
65 * DESCRIPTION: Allocate and initialize the default root named objects
66 *
67 * MUTEX: Locks namespace for entire execution
68 *
69 ******************************************************************************/
70
71 ACPI_STATUS
72 AcpiNsRootInitialize (
73 void)
74 {
75 ACPI_STATUS Status;
76 const ACPI_PREDEFINED_NAMES *InitVal = NULL;
77 ACPI_NAMESPACE_NODE *NewNode;
78 ACPI_OPERAND_OBJECT *ObjDesc;
79 ACPI_STRING Val = NULL;
80
81
82 ACPI_FUNCTION_TRACE (NsRootInitialize);
83
84
85 Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
86 if (ACPI_FAILURE (Status))
87 {
88 return_ACPI_STATUS (Status);
89 }
90
91 /*
92 * The global root ptr is initially NULL, so a non-NULL value indicates
93 * that AcpiNsRootInitialize() has already been called; just return.
94 */
95 if (AcpiGbl_RootNode)
96 {
97 Status = AE_OK;
98 goto UnlockAndExit;
99 }
100
101 /*
102 * Tell the rest of the subsystem that the root is initialized
103 * (This is OK because the namespace is locked)
104 */
105 AcpiGbl_RootNode = &AcpiGbl_RootNodeStruct;
106
107 /* Enter the pre-defined names in the name table */
108
109 ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
110 "Entering predefined entries into namespace\n"));
111
112 for (InitVal = AcpiGbl_PreDefinedNames; InitVal->Name; InitVal++)
113 {
114 /* _OSI is optional for now, will be permanent later */
115
116 if (!ACPI_STRCMP (InitVal->Name, "_OSI") && !AcpiGbl_CreateOsiMethod)
117 {
118 continue;
119 }
120
121 Status = AcpiNsLookup (NULL, InitVal->Name, InitVal->Type,
122 ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH,
123 NULL, &NewNode);
124
125 if (ACPI_FAILURE (Status) || (!NewNode)) /* Must be on same line for code converter */
126 {
127 ACPI_EXCEPTION ((AE_INFO, Status,
128 "Could not create predefined name %s",
129 InitVal->Name));
130 }
131
132 /*
133 * Name entered successfully. If entry in PreDefinedNames[] specifies
134 * an initial value, create the initial value.
135 */
136 if (InitVal->Val)
137 {
138 Status = AcpiOsPredefinedOverride (InitVal, &Val);
139 if (ACPI_FAILURE (Status))
140 {
141 ACPI_ERROR ((AE_INFO,
142 "Could not override predefined %s",
143 InitVal->Name));
144 }
145
146 if (!Val)
147 {
148 Val = InitVal->Val;
149 }
150
151 /*
152 * Entry requests an initial value, allocate a
153 * descriptor for it.
154 */
155 ObjDesc = AcpiUtCreateInternalObject (InitVal->Type);
156 if (!ObjDesc)
157 {
158 Status = AE_NO_MEMORY;
159 goto UnlockAndExit;
160 }
161
162 /*
163 * Convert value string from table entry to
164 * internal representation. Only types actually
165 * used for initial values are implemented here.
166 */
167 switch (InitVal->Type)
168 {
169 case ACPI_TYPE_METHOD:
170 ObjDesc->Method.ParamCount = (UINT8) ACPI_TO_INTEGER (Val);
171 ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
172
173 #if defined (ACPI_ASL_COMPILER)
174
175 /* Save the parameter count for the iASL compiler */
176
177 NewNode->Value = ObjDesc->Method.ParamCount;
178 #else
179 /* Mark this as a very SPECIAL method */
180
181 ObjDesc->Method.InfoFlags = ACPI_METHOD_INTERNAL_ONLY;
182 ObjDesc->Method.Dispatch.Implementation = AcpiUtOsiImplementation;
183 #endif
184 break;
185
186 case ACPI_TYPE_INTEGER:
187
188 ObjDesc->Integer.Value = ACPI_TO_INTEGER (Val);
189 break;
190
191
192 case ACPI_TYPE_STRING:
193
194 /* Build an object around the static string */
195
196 ObjDesc->String.Length = (UINT32) ACPI_STRLEN (Val);
197 ObjDesc->String.Pointer = Val;
198 ObjDesc->Common.Flags |= AOPOBJ_STATIC_POINTER;
199 break;
200
201
202 case ACPI_TYPE_MUTEX:
203
204 ObjDesc->Mutex.Node = NewNode;
205 ObjDesc->Mutex.SyncLevel = (UINT8) (ACPI_TO_INTEGER (Val) - 1);
206
207 /* Create a mutex */
208
209 Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex);
210 if (ACPI_FAILURE (Status))
211 {
212 AcpiUtRemoveReference (ObjDesc);
213 goto UnlockAndExit;
214 }
215
216 /* Special case for ACPI Global Lock */
217
218 if (ACPI_STRCMP (InitVal->Name, "_GL_") == 0)
219 {
220 AcpiGbl_GlobalLockMutex = ObjDesc;
221
222 /* Create additional counting semaphore for global lock */
223
224 Status = AcpiOsCreateSemaphore (
225 1, 0, &AcpiGbl_GlobalLockSemaphore);
226 if (ACPI_FAILURE (Status))
227 {
228 AcpiUtRemoveReference (ObjDesc);
229 goto UnlockAndExit;
230 }
231 }
232 break;
233
234
235 default:
236
237 ACPI_ERROR ((AE_INFO, "Unsupported initial type value 0x%X",
238 InitVal->Type));
239 AcpiUtRemoveReference (ObjDesc);
240 ObjDesc = NULL;
241 continue;
242 }
243
244 /* Store pointer to value descriptor in the Node */
245
246 Status = AcpiNsAttachObject (NewNode, ObjDesc,
247 ObjDesc->Common.Type);
248
249 /* Remove local reference to the object */
250
251 AcpiUtRemoveReference (ObjDesc);
252 }
253 }
254
255
256 UnlockAndExit:
257 (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
258
259 /* Save a handle to "_GPE", it is always present */
260
261 if (ACPI_SUCCESS (Status))
262 {
263 Status = AcpiNsGetNode (NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
264 &AcpiGbl_FadtGpeDevice);
265 }
266
267 return_ACPI_STATUS (Status);
268 }
269
270
271 /*******************************************************************************
272 *
273 * FUNCTION: AcpiNsLookup
274 *
275 * PARAMETERS: ScopeInfo - Current scope info block
276 * Pathname - Search pathname, in internal format
277 * (as represented in the AML stream)
278 * Type - Type associated with name
279 * InterpreterMode - IMODE_LOAD_PASS2 => add name if not found
280 * Flags - Flags describing the search restrictions
281 * WalkState - Current state of the walk
282 * ReturnNode - Where the Node is placed (if found
283 * or created successfully)
284 *
285 * RETURN: Status
286 *
287 * DESCRIPTION: Find or enter the passed name in the name space.
288 * Log an error if name not found in Exec mode.
289 *
290 * MUTEX: Assumes namespace is locked.
291 *
292 ******************************************************************************/
293
294 ACPI_STATUS
295 AcpiNsLookup (
296 ACPI_GENERIC_STATE *ScopeInfo,
297 char *Pathname,
298 ACPI_OBJECT_TYPE Type,
299 ACPI_INTERPRETER_MODE InterpreterMode,
300 UINT32 Flags,
301 ACPI_WALK_STATE *WalkState,
302 ACPI_NAMESPACE_NODE **ReturnNode)
303 {
304 ACPI_STATUS Status;
305 char *Path = Pathname;
306 ACPI_NAMESPACE_NODE *PrefixNode;
307 ACPI_NAMESPACE_NODE *CurrentNode = NULL;
308 ACPI_NAMESPACE_NODE *ThisNode = NULL;
309 UINT32 NumSegments;
310 UINT32 NumCarats;
311 ACPI_NAME SimpleName;
312 ACPI_OBJECT_TYPE TypeToCheckFor;
313 ACPI_OBJECT_TYPE ThisSearchType;
314 UINT32 SearchParentFlag = ACPI_NS_SEARCH_PARENT;
315 UINT32 LocalFlags;
316
317
318 ACPI_FUNCTION_TRACE (NsLookup);
319
320
321 if (!ReturnNode)
322 {
323 return_ACPI_STATUS (AE_BAD_PARAMETER);
324 }
325
326 LocalFlags = Flags & ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_SEARCH_PARENT);
327 *ReturnNode = ACPI_ENTRY_NOT_FOUND;
328 AcpiGbl_NsLookupCount++;
329
330 if (!AcpiGbl_RootNode)
331 {
332 return_ACPI_STATUS (AE_NO_NAMESPACE);
333 }
334
335 /* Get the prefix scope. A null scope means use the root scope */
336
337 if ((!ScopeInfo) ||
338 (!ScopeInfo->Scope.Node))
339 {
340 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
341 "Null scope prefix, using root node (%p)\n",
342 AcpiGbl_RootNode));
343
344 PrefixNode = AcpiGbl_RootNode;
345 }
346 else
347 {
348 PrefixNode = ScopeInfo->Scope.Node;
349 if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode) != ACPI_DESC_TYPE_NAMED)
350 {
351 ACPI_ERROR ((AE_INFO, "%p is not a namespace node [%s]",
352 PrefixNode, AcpiUtGetDescriptorName (PrefixNode)));
353 return_ACPI_STATUS (AE_AML_INTERNAL);
354 }
355
356 if (!(Flags & ACPI_NS_PREFIX_IS_SCOPE))
357 {
358 /*
359 * This node might not be a actual "scope" node (such as a
360 * Device/Method, etc.) It could be a Package or other object
361 * node. Backup up the tree to find the containing scope node.
362 */
363 while (!AcpiNsOpensScope (PrefixNode->Type) &&
364 PrefixNode->Type != ACPI_TYPE_ANY)
365 {
366 PrefixNode = PrefixNode->Parent;
367 }
368 }
369 }
370
371 /* Save type. TBD: may be no longer necessary */
372
373 TypeToCheckFor = Type;
374
375 /*
376 * Begin examination of the actual pathname
377 */
378 if (!Pathname)
379 {
380 /* A Null NamePath is allowed and refers to the root */
381
382 NumSegments = 0;
383 ThisNode = AcpiGbl_RootNode;
384 Path = "";
385
386 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
387 "Null Pathname (Zero segments), Flags=%X\n", Flags));
388 }
389 else
390 {
391 /*
392 * Name pointer is valid (and must be in internal name format)
393 *
394 * Check for scope prefixes:
395 *
396 * As represented in the AML stream, a namepath consists of an
397 * optional scope prefix followed by a name segment part.
398 *
399 * If present, the scope prefix is either a Root Prefix (in
400 * which case the name is fully qualified), or one or more
401 * Parent Prefixes (in which case the name's scope is relative
402 * to the current scope).
403 */
404 if (*Path == (UINT8) AML_ROOT_PREFIX)
405 {
406 /* Pathname is fully qualified, start from the root */
407
408 ThisNode = AcpiGbl_RootNode;
409 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
410
411 /* Point to name segment part */
412
413 Path++;
414
415 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
416 "Path is absolute from root [%p]\n", ThisNode));
417 }
418 else
419 {
420 /* Pathname is relative to current scope, start there */
421
422 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
423 "Searching relative to prefix scope [%4.4s] (%p)\n",
424 AcpiUtGetNodeName (PrefixNode), PrefixNode));
425
426 /*
427 * Handle multiple Parent Prefixes (carat) by just getting
428 * the parent node for each prefix instance.
429 */
430 ThisNode = PrefixNode;
431 NumCarats = 0;
432 while (*Path == (UINT8) AML_PARENT_PREFIX)
433 {
434 /* Name is fully qualified, no search rules apply */
435
436 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
437
438 /*
439 * Point past this prefix to the name segment
440 * part or the next Parent Prefix
441 */
442 Path++;
443
444 /* Backup to the parent node */
445
446 NumCarats++;
447 ThisNode = ThisNode->Parent;
448 if (!ThisNode)
449 {
450 /* Current scope has no parent scope */
451
452 ACPI_ERROR ((AE_INFO,
453 "ACPI path has too many parent prefixes (^) "
454 "- reached beyond root node"));
455 return_ACPI_STATUS (AE_NOT_FOUND);
456 }
457 }
458
459 if (SearchParentFlag == ACPI_NS_NO_UPSEARCH)
460 {
461 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
462 "Search scope is [%4.4s], path has %u carat(s)\n",
463 AcpiUtGetNodeName (ThisNode), NumCarats));
464 }
465 }
466
467 /*
468 * Determine the number of ACPI name segments in this pathname.
469 *
470 * The segment part consists of either:
471 * - A Null name segment (0)
472 * - A DualNamePrefix followed by two 4-byte name segments
473 * - A MultiNamePrefix followed by a byte indicating the
474 * number of segments and the segments themselves.
475 * - A single 4-byte name segment
476 *
477 * Examine the name prefix opcode, if any, to determine the number of
478 * segments.
479 */
480 switch (*Path)
481 {
482 case 0:
483 /*
484 * Null name after a root or parent prefixes. We already
485 * have the correct target node and there are no name segments.
486 */
487 NumSegments = 0;
488 Type = ThisNode->Type;
489
490 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
491 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
492 Flags));
493 break;
494
495 case AML_DUAL_NAME_PREFIX:
496
497 /* More than one NameSeg, search rules do not apply */
498
499 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
500
501 /* Two segments, point to first name segment */
502
503 NumSegments = 2;
504 Path++;
505
506 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
507 "Dual Pathname (2 segments, Flags=%X)\n", Flags));
508 break;
509
510 case AML_MULTI_NAME_PREFIX_OP:
511
512 /* More than one NameSeg, search rules do not apply */
513
514 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
515
516 /* Extract segment count, point to first name segment */
517
518 Path++;
519 NumSegments = (UINT32) (UINT8) *Path;
520 Path++;
521
522 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
523 "Multi Pathname (%u Segments, Flags=%X)\n",
524 NumSegments, Flags));
525 break;
526
527 default:
528 /*
529 * Not a Null name, no Dual or Multi prefix, hence there is
530 * only one name segment and Pathname is already pointing to it.
531 */
532 NumSegments = 1;
533
534 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
535 "Simple Pathname (1 segment, Flags=%X)\n", Flags));
536 break;
537 }
538
539 ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments, Path));
540 }
541
542
543 /*
544 * Search namespace for each segment of the name. Loop through and
545 * verify (or add to the namespace) each name segment.
546 *
547 * The object type is significant only at the last name
548 * segment. (We don't care about the types along the path, only
549 * the type of the final target object.)
550 */
551 ThisSearchType = ACPI_TYPE_ANY;
552 CurrentNode = ThisNode;
553 while (NumSegments && CurrentNode)
554 {
555 NumSegments--;
556 if (!NumSegments)
557 {
558 /* This is the last segment, enable typechecking */
559
560 ThisSearchType = Type;
561
562 /*
563 * Only allow automatic parent search (search rules) if the caller
564 * requested it AND we have a single, non-fully-qualified NameSeg
565 */
566 if ((SearchParentFlag != ACPI_NS_NO_UPSEARCH) &&
567 (Flags & ACPI_NS_SEARCH_PARENT))
568 {
569 LocalFlags |= ACPI_NS_SEARCH_PARENT;
570 }
571
572 /* Set error flag according to caller */
573
574 if (Flags & ACPI_NS_ERROR_IF_FOUND)
575 {
576 LocalFlags |= ACPI_NS_ERROR_IF_FOUND;
577 }
578 }
579
580 /* Extract one ACPI name from the front of the pathname */
581
582 ACPI_MOVE_32_TO_32 (&SimpleName, Path);
583
584 /* Try to find the single (4 character) ACPI name */
585
586 Status = AcpiNsSearchAndEnter (SimpleName, WalkState, CurrentNode,
587 InterpreterMode, ThisSearchType, LocalFlags, &ThisNode);
588 if (ACPI_FAILURE (Status))
589 {
590 if (Status == AE_NOT_FOUND)
591 {
592 /* Name not found in ACPI namespace */
593
594 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
595 "Name [%4.4s] not found in scope [%4.4s] %p\n",
596 (char *) &SimpleName, (char *) &CurrentNode->Name,
597 CurrentNode));
598 }
599
600 *ReturnNode = ThisNode;
601 return_ACPI_STATUS (Status);
602 }
603
604 /* More segments to follow? */
605
606 if (NumSegments > 0)
607 {
608 /*
609 * If we have an alias to an object that opens a scope (such as a
610 * device or processor), we need to dereference the alias here so
611 * that we can access any children of the original node (via the
612 * remaining segments).
613 */
614 if (ThisNode->Type == ACPI_TYPE_LOCAL_ALIAS)
615 {
616 if (!ThisNode->Object)
617 {
618 return_ACPI_STATUS (AE_NOT_EXIST);
619 }
620
621 if (AcpiNsOpensScope (((ACPI_NAMESPACE_NODE *)
622 ThisNode->Object)->Type))
623 {
624 ThisNode = (ACPI_NAMESPACE_NODE *) ThisNode->Object;
625 }
626 }
627 }
628
629 /* Special handling for the last segment (NumSegments == 0) */
630
631 else
632 {
633 /*
634 * Sanity typecheck of the target object:
635 *
636 * If 1) This is the last segment (NumSegments == 0)
637 * 2) And we are looking for a specific type
638 * (Not checking for TYPE_ANY)
639 * 3) Which is not an alias
640 * 4) Which is not a local type (TYPE_SCOPE)
641 * 5) And the type of target object is known (not TYPE_ANY)
642 * 6) And target object does not match what we are looking for
643 *
644 * Then we have a type mismatch. Just warn and ignore it.
645 */
646 if ((TypeToCheckFor != ACPI_TYPE_ANY) &&
647 (TypeToCheckFor != ACPI_TYPE_LOCAL_ALIAS) &&
648 (TypeToCheckFor != ACPI_TYPE_LOCAL_METHOD_ALIAS) &&
649 (TypeToCheckFor != ACPI_TYPE_LOCAL_SCOPE) &&
650 (ThisNode->Type != ACPI_TYPE_ANY) &&
651 (ThisNode->Type != TypeToCheckFor))
652 {
653 /* Complain about a type mismatch */
654
655 ACPI_WARNING ((AE_INFO,
656 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
657 ACPI_CAST_PTR (char, &SimpleName),
658 AcpiUtGetTypeName (ThisNode->Type),
659 AcpiUtGetTypeName (TypeToCheckFor)));
660 }
661
662 /*
663 * If this is the last name segment and we are not looking for a
664 * specific type, but the type of found object is known, use that
665 * type to (later) see if it opens a scope.
666 */
667 if (Type == ACPI_TYPE_ANY)
668 {
669 Type = ThisNode->Type;
670 }
671 }
672
673 /* Point to next name segment and make this node current */
674
675 Path += ACPI_NAME_SIZE;
676 CurrentNode = ThisNode;
677 }
678
679 /* Always check if we need to open a new scope */
680
681 if (!(Flags & ACPI_NS_DONT_OPEN_SCOPE) && (WalkState))
682 {
683 /*
684 * If entry is a type which opens a scope, push the new scope on the
685 * scope stack.
686 */
687 if (AcpiNsOpensScope (Type))
688 {
689 Status = AcpiDsScopeStackPush (ThisNode, Type, WalkState);
690 if (ACPI_FAILURE (Status))
691 {
692 return_ACPI_STATUS (Status);
693 }
694 }
695 }
696
697 *ReturnNode = ThisNode;
698 return_ACPI_STATUS (AE_OK);
699 }
700