xref: /freebsd/sys/contrib/dev/acpica/components/namespace/nssearch.c (revision e6e746bfb086d563bf0ad454a33ecbcab8836dbf)
1 /*******************************************************************************
2  *
3  * Module Name: nssearch - Namespace search
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, 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 <contrib/dev/acpica/include/acpi.h>
45 #include <contrib/dev/acpica/include/accommon.h>
46 #include <contrib/dev/acpica/include/acnamesp.h>
47 
48 #ifdef ACPI_ASL_COMPILER
49 #include <contrib/dev/acpica/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 = AcpiNsGetExternalPathname (ParentNode);
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             (Flags & ACPI_NS_ERROR_IF_FOUND))
343         {
344             Status = AE_ALREADY_EXISTS;
345         }
346 
347 #ifdef ACPI_ASL_COMPILER
348         if (*ReturnNode && (*ReturnNode)->Type == ACPI_TYPE_ANY)
349         {
350             (*ReturnNode)->Flags |= ANOBJ_IS_EXTERNAL;
351         }
352 #endif
353 
354         /* Either found it or there was an error: finished either way */
355 
356         return_ACPI_STATUS (Status);
357     }
358 
359     /*
360      * The name was not found. If we are NOT performing the first pass
361      * (name entry) of loading the namespace, search the parent tree (all the
362      * way to the root if necessary.) We don't want to perform the parent
363      * search when the namespace is actually being loaded. We want to perform
364      * the search when namespace references are being resolved (load pass 2)
365      * and during the execution phase.
366      */
367     if ((InterpreterMode != ACPI_IMODE_LOAD_PASS1) &&
368         (Flags & ACPI_NS_SEARCH_PARENT))
369     {
370         /*
371          * Not found at this level - search parent tree according to the
372          * ACPI specification
373          */
374         Status = AcpiNsSearchParentTree (TargetName, Node, Type, ReturnNode);
375         if (ACPI_SUCCESS (Status))
376         {
377             return_ACPI_STATUS (Status);
378         }
379     }
380 
381     /* In execute mode, just search, never add names. Exit now */
382 
383     if (InterpreterMode == ACPI_IMODE_EXECUTE)
384     {
385         ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
386             "%4.4s Not found in %p [Not adding]\n",
387             ACPI_CAST_PTR (char, &TargetName), Node));
388 
389         return_ACPI_STATUS (AE_NOT_FOUND);
390     }
391 
392     /* Create the new named object */
393 
394     NewNode = AcpiNsCreateNode (TargetName);
395     if (!NewNode)
396     {
397         return_ACPI_STATUS (AE_NO_MEMORY);
398     }
399 
400 #ifdef ACPI_ASL_COMPILER
401 
402     /* Node is an object defined by an External() statement */
403 
404     if (Flags & ACPI_NS_EXTERNAL ||
405         (WalkState && WalkState->Opcode == AML_SCOPE_OP))
406     {
407         NewNode->Flags |= ANOBJ_IS_EXTERNAL;
408     }
409 #endif
410 
411     if (Flags & ACPI_NS_TEMPORARY)
412     {
413         NewNode->Flags |= ANOBJ_TEMPORARY;
414     }
415 
416     /* Install the new object into the parent's list of children */
417 
418     AcpiNsInstallNode (WalkState, Node, NewNode, Type);
419     *ReturnNode = NewNode;
420     return_ACPI_STATUS (AE_OK);
421 }
422