1/*******************************************************************************
2 *
3 * Module Name: nssearch - Namespace search
4 *
5 ******************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2013, 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 __NSSEARCH_C__
45
46#include <contrib/dev/acpica/include/acpi.h>
47#include <contrib/dev/acpica/include/accommon.h>
48#include <contrib/dev/acpica/include/acnamesp.h>
49
50#ifdef ACPI_ASL_COMPILER
51#include <contrib/dev/acpica/include/amlcode.h>
52#endif
53
54#define _COMPONENT          ACPI_NAMESPACE
55        ACPI_MODULE_NAME    ("nssearch")
56
57/* Local prototypes */
58
59static ACPI_STATUS
60AcpiNsSearchParentTree (
61    UINT32                  TargetName,
62    ACPI_NAMESPACE_NODE     *Node,
63    ACPI_OBJECT_TYPE        Type,
64    ACPI_NAMESPACE_NODE     **ReturnNode);
65
66
67/*******************************************************************************
68 *
69 * FUNCTION:    AcpiNsSearchOneScope
70 *
71 * PARAMETERS:  TargetName      - Ascii ACPI name to search for
72 *              ParentNode      - Starting node where search will begin
73 *              Type            - Object type to match
74 *              ReturnNode      - Where the matched Named obj is returned
75 *
76 * RETURN:      Status
77 *
78 * DESCRIPTION: Search a single level of the namespace. Performs a
79 *              simple search of the specified level, and does not add
80 *              entries or search parents.
81 *
82 *
83 *      Named object lists are built (and subsequently dumped) in the
84 *      order in which the names are encountered during the namespace load;
85 *
86 *      All namespace searching is linear in this implementation, but
87 *      could be easily modified to support any improved search
88 *      algorithm. However, the linear search was chosen for simplicity
89 *      and because the trees are small and the other interpreter
90 *      execution overhead is relatively high.
91 *
92 *      Note: CPU execution analysis has shown that the AML interpreter spends
93 *      a very small percentage of its time searching the namespace. Therefore,
94 *      the linear search seems to be sufficient, as there would seem to be
95 *      little value in improving the search.
96 *
97 ******************************************************************************/
98
99ACPI_STATUS
100AcpiNsSearchOneScope (
101    UINT32                  TargetName,
102    ACPI_NAMESPACE_NODE     *ParentNode,
103    ACPI_OBJECT_TYPE        Type,
104    ACPI_NAMESPACE_NODE     **ReturnNode)
105{
106    ACPI_NAMESPACE_NODE     *Node;
107
108
109    ACPI_FUNCTION_TRACE (NsSearchOneScope);
110
111
112#ifdef ACPI_DEBUG_OUTPUT
113    if (ACPI_LV_NAMES & AcpiDbgLevel)
114    {
115        char                *ScopeName;
116
117        ScopeName = AcpiNsGetExternalPathname (ParentNode);
118        if (ScopeName)
119        {
120            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
121                "Searching %s (%p) For [%4.4s] (%s)\n",
122                ScopeName, ParentNode, ACPI_CAST_PTR (char, &TargetName),
123                AcpiUtGetTypeName (Type)));
124
125            ACPI_FREE (ScopeName);
126        }
127    }
128#endif
129
130    /*
131     * Search for name at this namespace level, which is to say that we
132     * must search for the name among the children of this object
133     */
134    Node = ParentNode->Child;
135    while (Node)
136    {
137        /* Check for match against the name */
138
139        if (Node->Name.Integer == TargetName)
140        {
141            /* Resolve a control method alias if any */
142
143            if (AcpiNsGetType (Node) == ACPI_TYPE_LOCAL_METHOD_ALIAS)
144            {
145                Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, Node->Object);
146            }
147
148            /* Found matching entry */
149
150            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
151                "Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n",
152                ACPI_CAST_PTR (char, &TargetName),
153                AcpiUtGetTypeName (Node->Type),
154                Node, AcpiUtGetNodeName (ParentNode), ParentNode));
155
156            *ReturnNode = Node;
157            return_ACPI_STATUS (AE_OK);
158        }
159
160        /* Didn't match name, move on to the next peer object */
161
162        Node = Node->Peer;
163    }
164
165    /* Searched entire namespace level, not found */
166
167    ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
168        "Name [%4.4s] (%s) not found in search in scope [%4.4s] "
169        "%p first child %p\n",
170        ACPI_CAST_PTR (char, &TargetName), AcpiUtGetTypeName (Type),
171        AcpiUtGetNodeName (ParentNode), ParentNode, ParentNode->Child));
172
173    return_ACPI_STATUS (AE_NOT_FOUND);
174}
175
176
177/*******************************************************************************
178 *
179 * FUNCTION:    AcpiNsSearchParentTree
180 *
181 * PARAMETERS:  TargetName      - Ascii ACPI name to search for
182 *              Node            - Starting node where search will begin
183 *              Type            - Object type to match
184 *              ReturnNode      - Where the matched Node is returned
185 *
186 * RETURN:      Status
187 *
188 * DESCRIPTION: Called when a name has not been found in the current namespace
189 *              level. Before adding it or giving up, ACPI scope rules require
190 *              searching enclosing scopes in cases identified by AcpiNsLocal().
191 *
192 *              "A name is located by finding the matching name in the current
193 *              name space, and then in the parent name space. If the parent
194 *              name space does not contain the name, the search continues
195 *              recursively until either the name is found or the name space
196 *              does not have a parent (the root of the name space). This
197 *              indicates that the name is not found" (From ACPI Specification,
198 *              section 5.3)
199 *
200 ******************************************************************************/
201
202static ACPI_STATUS
203AcpiNsSearchParentTree (
204    UINT32                  TargetName,
205    ACPI_NAMESPACE_NODE     *Node,
206    ACPI_OBJECT_TYPE        Type,
207    ACPI_NAMESPACE_NODE     **ReturnNode)
208{
209    ACPI_STATUS             Status;
210    ACPI_NAMESPACE_NODE     *ParentNode;
211
212
213    ACPI_FUNCTION_TRACE (NsSearchParentTree);
214
215
216    ParentNode = Node->Parent;
217
218    /*
219     * If there is no parent (i.e., we are at the root) or type is "local",
220     * we won't be searching the parent tree.
221     */
222    if (!ParentNode)
223    {
224        ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "[%4.4s] has no parent\n",
225            ACPI_CAST_PTR (char, &TargetName)));
226        return_ACPI_STATUS (AE_NOT_FOUND);
227    }
228
229    if (AcpiNsLocal (Type))
230    {
231        ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
232            "[%4.4s] type [%s] must be local to this scope (no parent search)\n",
233            ACPI_CAST_PTR (char, &TargetName), AcpiUtGetTypeName (Type)));
234        return_ACPI_STATUS (AE_NOT_FOUND);
235    }
236
237    /* Search the parent tree */
238
239    ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
240        "Searching parent [%4.4s] for [%4.4s]\n",
241        AcpiUtGetNodeName (ParentNode), ACPI_CAST_PTR (char, &TargetName)));
242
243    /* Search parents until target is found or we have backed up to the root */
244
245    while (ParentNode)
246    {
247        /*
248         * Search parent scope. Use TYPE_ANY because we don't care about the
249         * object type at this point, we only care about the existence of
250         * the actual name we are searching for. Typechecking comes later.
251         */
252        Status = AcpiNsSearchOneScope (
253                    TargetName, ParentNode, ACPI_TYPE_ANY, ReturnNode);
254        if (ACPI_SUCCESS (Status))
255        {
256            return_ACPI_STATUS (Status);
257        }
258
259        /* Not found here, go up another level (until we reach the root) */
260
261        ParentNode = ParentNode->Parent;
262    }
263
264    /* Not found in parent tree */
265
266    return_ACPI_STATUS (AE_NOT_FOUND);
267}
268
269
270/*******************************************************************************
271 *
272 * FUNCTION:    AcpiNsSearchAndEnter
273 *
274 * PARAMETERS:  TargetName          - Ascii ACPI name to search for (4 chars)
275 *              WalkState           - Current state of the walk
276 *              Node                - Starting node where search will begin
277 *              InterpreterMode     - Add names only in ACPI_MODE_LOAD_PASS_x.
278 *                                    Otherwise,search only.
279 *              Type                - Object type to match
280 *              Flags               - Flags describing the search restrictions
281 *              ReturnNode          - Where the Node is returned
282 *
283 * RETURN:      Status
284 *
285 * DESCRIPTION: Search for a name segment in a single namespace level,
286 *              optionally adding it if it is not found. If the passed
287 *              Type is not Any and the type previously stored in the
288 *              entry was Any (i.e. unknown), update the stored type.
289 *
290 *              In ACPI_IMODE_EXECUTE, search only.
291 *              In other modes, search and add if not found.
292 *
293 ******************************************************************************/
294
295ACPI_STATUS
296AcpiNsSearchAndEnter (
297    UINT32                  TargetName,
298    ACPI_WALK_STATE         *WalkState,
299    ACPI_NAMESPACE_NODE     *Node,
300    ACPI_INTERPRETER_MODE   InterpreterMode,
301    ACPI_OBJECT_TYPE        Type,
302    UINT32                  Flags,
303    ACPI_NAMESPACE_NODE     **ReturnNode)
304{
305    ACPI_STATUS             Status;
306    ACPI_NAMESPACE_NODE     *NewNode;
307
308
309    ACPI_FUNCTION_TRACE (NsSearchAndEnter);
310
311
312    /* Parameter validation */
313
314    if (!Node || !TargetName || !ReturnNode)
315    {
316        ACPI_ERROR ((AE_INFO,
317            "Null parameter: Node %p Name 0x%X ReturnNode %p",
318            Node, TargetName, ReturnNode));
319        return_ACPI_STATUS (AE_BAD_PARAMETER);
320    }
321
322    /*
323     * Name must consist of valid ACPI characters. We will repair the name if
324     * necessary because we don't want to abort because of this, but we want
325     * all namespace names to be printable. A warning message is appropriate.
326     *
327     * This issue came up because there are in fact machines that exhibit
328     * this problem, and we want to be able to enable ACPI support for them,
329     * even though there are a few bad names.
330     */
331    AcpiUtRepairName (ACPI_CAST_PTR (char, &TargetName));
332
333    /* Try to find the name in the namespace level specified by the caller */
334
335    *ReturnNode = ACPI_ENTRY_NOT_FOUND;
336    Status = AcpiNsSearchOneScope (TargetName, Node, Type, ReturnNode);
337    if (Status != AE_NOT_FOUND)
338    {
339        /*
340         * If we found it AND the request specifies that a find is an error,
341         * return the error
342         */
343        if ((Status == AE_OK) &&
344            (Flags & ACPI_NS_ERROR_IF_FOUND))
345        {
346            Status = AE_ALREADY_EXISTS;
347        }
348
349#ifdef ACPI_ASL_COMPILER
350        if (*ReturnNode && (*ReturnNode)->Type == ACPI_TYPE_ANY)
351        {
352            (*ReturnNode)->Flags |= ANOBJ_IS_EXTERNAL;
353        }
354#endif
355
356        /* Either found it or there was an error: finished either way */
357
358        return_ACPI_STATUS (Status);
359    }
360
361    /*
362     * The name was not found. If we are NOT performing the first pass
363     * (name entry) of loading the namespace, search the parent tree (all the
364     * way to the root if necessary.) We don't want to perform the parent
365     * search when the namespace is actually being loaded. We want to perform
366     * the search when namespace references are being resolved (load pass 2)
367     * and during the execution phase.
368     */
369    if ((InterpreterMode != ACPI_IMODE_LOAD_PASS1) &&
370        (Flags & ACPI_NS_SEARCH_PARENT))
371    {
372        /*
373         * Not found at this level - search parent tree according to the
374         * ACPI specification
375         */
376        Status = AcpiNsSearchParentTree (TargetName, Node, Type, ReturnNode);
377        if (ACPI_SUCCESS (Status))
378        {
379            return_ACPI_STATUS (Status);
380        }
381    }
382
383    /* In execute mode, just search, never add names. Exit now */
384
385    if (InterpreterMode == ACPI_IMODE_EXECUTE)
386    {
387        ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
388            "%4.4s Not found in %p [Not adding]\n",
389            ACPI_CAST_PTR (char, &TargetName), Node));
390
391        return_ACPI_STATUS (AE_NOT_FOUND);
392    }
393
394    /* Create the new named object */
395
396    NewNode = AcpiNsCreateNode (TargetName);
397    if (!NewNode)
398    {
399        return_ACPI_STATUS (AE_NO_MEMORY);
400    }
401
402#ifdef ACPI_ASL_COMPILER
403
404    /* Node is an object defined by an External() statement */
405
406    if (Flags & ACPI_NS_EXTERNAL ||
407        (WalkState && WalkState->Opcode == AML_SCOPE_OP))
408    {
409        NewNode->Flags |= ANOBJ_IS_EXTERNAL;
410    }
411#endif
412
413    if (Flags & ACPI_NS_TEMPORARY)
414    {
415        NewNode->Flags |= ANOBJ_TEMPORARY;
416    }
417
418    /* Install the new object into the parent's list of children */
419
420    AcpiNsInstallNode (WalkState, Node, NewNode, Type);
421    *ReturnNode = NewNode;
422    return_ACPI_STATUS (AE_OK);
423}
424