30f7ce2b31e4261e004cf1b7755ba3f426ee78c0
[reactos.git] / drivers / bus / acpi / acpica / namespace / nssearch.c
1 /*******************************************************************************
2 *
3 * Module Name: nssearch - Namespace search
4 *
5 ******************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2017, 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 #include "acpi.h"
45 #include "accommon.h"
46 #include "acnamesp.h"
47
48 #ifdef ACPI_ASL_COMPILER
49 #include "amlcode.h"
50 #endif
51
52 #define _COMPONENT ACPI_NAMESPACE
53 ACPI_MODULE_NAME ("nssearch")
54
55 /* Local prototypes */
56
57 static ACPI_STATUS
58 AcpiNsSearchParentTree (
59 UINT32 TargetName,
60 ACPI_NAMESPACE_NODE *Node,
61 ACPI_OBJECT_TYPE Type,
62 ACPI_NAMESPACE_NODE **ReturnNode);
63
64
65 /*******************************************************************************
66 *
67 * FUNCTION: AcpiNsSearchOneScope
68 *
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
73 *
74 * RETURN: Status
75 *
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.
79 *
80 *
81 * Named object lists are built (and subsequently dumped) in the
82 * order in which the names are encountered during the namespace load;
83 *
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.
89 *
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.
94 *
95 ******************************************************************************/
96
97 ACPI_STATUS
98 AcpiNsSearchOneScope (
99 UINT32 TargetName,
100 ACPI_NAMESPACE_NODE *ParentNode,
101 ACPI_OBJECT_TYPE Type,
102 ACPI_NAMESPACE_NODE **ReturnNode)
103 {
104 ACPI_NAMESPACE_NODE *Node;
105
106
107 ACPI_FUNCTION_TRACE (NsSearchOneScope);
108
109
110 #ifdef ACPI_DEBUG_OUTPUT
111 if (ACPI_LV_NAMES & AcpiDbgLevel)
112 {
113 char *ScopeName;
114
115 ScopeName = AcpiNsGetNormalizedPathname (ParentNode, TRUE);
116 if (ScopeName)
117 {
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)));
122
123 ACPI_FREE (ScopeName);
124 }
125 }
126 #endif
127
128 /*
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
131 */
132 Node = ParentNode->Child;
133 while (Node)
134 {
135 /* Check for match against the name */
136
137 if (Node->Name.Integer == TargetName)
138 {
139 /* Resolve a control method alias if any */
140
141 if (AcpiNsGetType (Node) == ACPI_TYPE_LOCAL_METHOD_ALIAS)
142 {
143 Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, Node->Object);
144 }
145
146 /* Found matching entry */
147
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));
153
154 *ReturnNode = Node;
155 return_ACPI_STATUS (AE_OK);
156 }
157
158 /* Didn't match name, move on to the next peer object */
159
160 Node = Node->Peer;
161 }
162
163 /* Searched entire namespace level, not found */
164
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));
170
171 return_ACPI_STATUS (AE_NOT_FOUND);
172 }
173
174
175 /*******************************************************************************
176 *
177 * FUNCTION: AcpiNsSearchParentTree
178 *
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
183 *
184 * RETURN: Status
185 *
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().
189 *
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,
196 * section 5.3)
197 *
198 ******************************************************************************/
199
200 static ACPI_STATUS
201 AcpiNsSearchParentTree (
202 UINT32 TargetName,
203 ACPI_NAMESPACE_NODE *Node,
204 ACPI_OBJECT_TYPE Type,
205 ACPI_NAMESPACE_NODE **ReturnNode)
206 {
207 ACPI_STATUS Status;
208 ACPI_NAMESPACE_NODE *ParentNode;
209
210
211 ACPI_FUNCTION_TRACE (NsSearchParentTree);
212
213
214 ParentNode = Node->Parent;
215
216 /*
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.
219 */
220 if (!ParentNode)
221 {
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);
225 }
226
227 if (AcpiNsLocal (Type))
228 {
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);
233 }
234
235 /* Search the parent tree */
236
237 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
238 "Searching parent [%4.4s] for [%4.4s]\n",
239 AcpiUtGetNodeName (ParentNode), ACPI_CAST_PTR (char, &TargetName)));
240
241 /* Search parents until target is found or we have backed up to the root */
242
243 while (ParentNode)
244 {
245 /*
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.
249 */
250 Status = AcpiNsSearchOneScope (
251 TargetName, ParentNode, ACPI_TYPE_ANY, ReturnNode);
252 if (ACPI_SUCCESS (Status))
253 {
254 return_ACPI_STATUS (Status);
255 }
256
257 /* Not found here, go up another level (until we reach the root) */
258
259 ParentNode = ParentNode->Parent;
260 }
261
262 /* Not found in parent tree */
263
264 return_ACPI_STATUS (AE_NOT_FOUND);
265 }
266
267
268 /*******************************************************************************
269 *
270 * FUNCTION: AcpiNsSearchAndEnter
271 *
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
280 *
281 * RETURN: Status
282 *
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.
287 *
288 * In ACPI_IMODE_EXECUTE, search only.
289 * In other modes, search and add if not found.
290 *
291 ******************************************************************************/
292
293 ACPI_STATUS
294 AcpiNsSearchAndEnter (
295 UINT32 TargetName,
296 ACPI_WALK_STATE *WalkState,
297 ACPI_NAMESPACE_NODE *Node,
298 ACPI_INTERPRETER_MODE InterpreterMode,
299 ACPI_OBJECT_TYPE Type,
300 UINT32 Flags,
301 ACPI_NAMESPACE_NODE **ReturnNode)
302 {
303 ACPI_STATUS Status;
304 ACPI_NAMESPACE_NODE *NewNode;
305
306
307 ACPI_FUNCTION_TRACE (NsSearchAndEnter);
308
309
310 /* Parameter validation */
311
312 if (!Node || !TargetName || !ReturnNode)
313 {
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);
318 }
319
320 /*
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.
324 *
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.
328 */
329 AcpiUtRepairName (ACPI_CAST_PTR (char, &TargetName));
330
331 /* Try to find the name in the namespace level specified by the caller */
332
333 *ReturnNode = ACPI_ENTRY_NOT_FOUND;
334 Status = AcpiNsSearchOneScope (TargetName, Node, Type, ReturnNode);
335 if (Status != AE_NOT_FOUND)
336 {
337 /*
338 * If we found it AND the request specifies that a find is an error,
339 * return the error
340 */
341 if (Status == AE_OK)
342 {
343 /* The node was found in the namespace */
344
345 /*
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.
349 */
350 if (Flags & ACPI_NS_OVERRIDE_IF_FOUND)
351 {
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));
356
357 AcpiNsDeleteChildren (*ReturnNode);
358 if (AcpiGbl_RuntimeNamespaceOverride)
359 {
360 AcpiUtRemoveReference ((*ReturnNode)->Object);
361 (*ReturnNode)->Object = NULL;
362 (*ReturnNode)->OwnerId = WalkState->OwnerId;
363 }
364 else
365 {
366 AcpiNsRemoveNode (*ReturnNode);
367 *ReturnNode = ACPI_ENTRY_NOT_FOUND;
368 }
369 }
370
371 /* Return an error if we don't expect to find the object */
372
373 else if (Flags & ACPI_NS_ERROR_IF_FOUND)
374 {
375 Status = AE_ALREADY_EXISTS;
376 }
377 }
378
379 #ifdef ACPI_ASL_COMPILER
380 if (*ReturnNode && (*ReturnNode)->Type == ACPI_TYPE_ANY)
381 {
382 (*ReturnNode)->Flags |= ANOBJ_IS_EXTERNAL;
383 }
384 #endif
385
386 /* Either found it or there was an error: finished either way */
387
388 return_ACPI_STATUS (Status);
389 }
390
391 /*
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.
398 */
399 if ((InterpreterMode != ACPI_IMODE_LOAD_PASS1) &&
400 (Flags & ACPI_NS_SEARCH_PARENT))
401 {
402 /*
403 * Not found at this level - search parent tree according to the
404 * ACPI specification
405 */
406 Status = AcpiNsSearchParentTree (TargetName, Node, Type, ReturnNode);
407 if (ACPI_SUCCESS (Status))
408 {
409 return_ACPI_STATUS (Status);
410 }
411 }
412
413 /* In execute mode, just search, never add names. Exit now */
414
415 if (InterpreterMode == ACPI_IMODE_EXECUTE)
416 {
417 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
418 "%4.4s Not found in %p [Not adding]\n",
419 ACPI_CAST_PTR (char, &TargetName), Node));
420
421 return_ACPI_STATUS (AE_NOT_FOUND);
422 }
423
424 /* Create the new named object */
425
426 NewNode = AcpiNsCreateNode (TargetName);
427 if (!NewNode)
428 {
429 return_ACPI_STATUS (AE_NO_MEMORY);
430 }
431
432 #ifdef ACPI_ASL_COMPILER
433
434 /* Node is an object defined by an External() statement */
435
436 if (Flags & ACPI_NS_EXTERNAL ||
437 (WalkState && WalkState->Opcode == AML_SCOPE_OP))
438 {
439 NewNode->Flags |= ANOBJ_IS_EXTERNAL;
440 }
441 #endif
442
443 if (Flags & ACPI_NS_TEMPORARY)
444 {
445 NewNode->Flags |= ANOBJ_TEMPORARY;
446 }
447
448 /* Install the new object into the parent's list of children */
449
450 AcpiNsInstallNode (WalkState, Node, NewNode, Type);
451 *ReturnNode = NewNode;
452 return_ACPI_STATUS (AE_OK);
453 }