xref: /haiku/src/add-ons/kernel/bus_managers/acpi/acpica/components/namespace/nswalk.c (revision d0ac609964842f8cdb6d54b3c539c6c15293e172)
1 /******************************************************************************
2  *
3  * Module Name: nswalk - Functions for walking the ACPI namespace
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2015, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************/
115 
116 #include "acpi.h"
117 #include "accommon.h"
118 #include "acnamesp.h"
119 
120 
121 #define _COMPONENT          ACPI_NAMESPACE
122         ACPI_MODULE_NAME    ("nswalk")
123 
124 
125 /*******************************************************************************
126  *
127  * FUNCTION:    AcpiNsGetNextNode
128  *
129  * PARAMETERS:  ParentNode          - Parent node whose children we are
130  *                                    getting
131  *              ChildNode           - Previous child that was found.
132  *                                    The NEXT child will be returned
133  *
134  * RETURN:      ACPI_NAMESPACE_NODE - Pointer to the NEXT child or NULL if
135  *                                    none is found.
136  *
137  * DESCRIPTION: Return the next peer node within the namespace. If Handle
138  *              is valid, Scope is ignored. Otherwise, the first node
139  *              within Scope is returned.
140  *
141  ******************************************************************************/
142 
143 ACPI_NAMESPACE_NODE *
144 AcpiNsGetNextNode (
145     ACPI_NAMESPACE_NODE     *ParentNode,
146     ACPI_NAMESPACE_NODE     *ChildNode)
147 {
148     ACPI_FUNCTION_ENTRY ();
149 
150 
151     if (!ChildNode)
152     {
153         /* It's really the parent's _scope_ that we want */
154 
155         return (ParentNode->Child);
156     }
157 
158     /* Otherwise just return the next peer */
159 
160     return (ChildNode->Peer);
161 }
162 
163 
164 /*******************************************************************************
165  *
166  * FUNCTION:    AcpiNsGetNextNodeTyped
167  *
168  * PARAMETERS:  Type                - Type of node to be searched for
169  *              ParentNode          - Parent node whose children we are
170  *                                    getting
171  *              ChildNode           - Previous child that was found.
172  *                                    The NEXT child will be returned
173  *
174  * RETURN:      ACPI_NAMESPACE_NODE - Pointer to the NEXT child or NULL if
175  *                                    none is found.
176  *
177  * DESCRIPTION: Return the next peer node within the namespace. If Handle
178  *              is valid, Scope is ignored. Otherwise, the first node
179  *              within Scope is returned.
180  *
181  ******************************************************************************/
182 
183 ACPI_NAMESPACE_NODE *
184 AcpiNsGetNextNodeTyped (
185     ACPI_OBJECT_TYPE        Type,
186     ACPI_NAMESPACE_NODE     *ParentNode,
187     ACPI_NAMESPACE_NODE     *ChildNode)
188 {
189     ACPI_NAMESPACE_NODE     *NextNode = NULL;
190 
191 
192     ACPI_FUNCTION_ENTRY ();
193 
194 
195     NextNode = AcpiNsGetNextNode (ParentNode, ChildNode);
196 
197     /* If any type is OK, we are done */
198 
199     if (Type == ACPI_TYPE_ANY)
200     {
201         /* NextNode is NULL if we are at the end-of-list */
202 
203         return (NextNode);
204     }
205 
206     /* Must search for the node -- but within this scope only */
207 
208     while (NextNode)
209     {
210         /* If type matches, we are done */
211 
212         if (NextNode->Type == Type)
213         {
214             return (NextNode);
215         }
216 
217         /* Otherwise, move on to the next peer node */
218 
219         NextNode = NextNode->Peer;
220     }
221 
222     /* Not found */
223 
224     return (NULL);
225 }
226 
227 
228 /*******************************************************************************
229  *
230  * FUNCTION:    AcpiNsWalkNamespace
231  *
232  * PARAMETERS:  Type                - ACPI_OBJECT_TYPE to search for
233  *              StartNode           - Handle in namespace where search begins
234  *              MaxDepth            - Depth to which search is to reach
235  *              Flags               - Whether to unlock the NS before invoking
236  *                                    the callback routine
237  *              DescendingCallback  - Called during tree descent
238  *                                    when an object of "Type" is found
239  *              AscendingCallback   - Called during tree ascent
240  *                                    when an object of "Type" is found
241  *              Context             - Passed to user function(s) above
242  *              ReturnValue         - from the UserFunction if terminated
243  *                                    early. Otherwise, returns NULL.
244  * RETURNS:     Status
245  *
246  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
247  *              starting (and ending) at the node specified by StartHandle.
248  *              The callback function is called whenever a node that matches
249  *              the type parameter is found. If the callback function returns
250  *              a non-zero value, the search is terminated immediately and
251  *              this value is returned to the caller.
252  *
253  *              The point of this procedure is to provide a generic namespace
254  *              walk routine that can be called from multiple places to
255  *              provide multiple services; the callback function(s) can be
256  *              tailored to each task, whether it is a print function,
257  *              a compare function, etc.
258  *
259  ******************************************************************************/
260 
261 ACPI_STATUS
262 AcpiNsWalkNamespace (
263     ACPI_OBJECT_TYPE        Type,
264     ACPI_HANDLE             StartNode,
265     UINT32                  MaxDepth,
266     UINT32                  Flags,
267     ACPI_WALK_CALLBACK      DescendingCallback,
268     ACPI_WALK_CALLBACK      AscendingCallback,
269     void                    *Context,
270     void                    **ReturnValue)
271 {
272     ACPI_STATUS             Status;
273     ACPI_STATUS             MutexStatus;
274     ACPI_NAMESPACE_NODE     *ChildNode;
275     ACPI_NAMESPACE_NODE     *ParentNode;
276     ACPI_OBJECT_TYPE        ChildType;
277     UINT32                  Level;
278     BOOLEAN                 NodePreviouslyVisited = FALSE;
279 
280 
281     ACPI_FUNCTION_TRACE (NsWalkNamespace);
282 
283 
284     /* Special case for the namespace Root Node */
285 
286     if (StartNode == ACPI_ROOT_OBJECT)
287     {
288         StartNode = AcpiGbl_RootNode;
289     }
290 
291     /* Null child means "get first node" */
292 
293     ParentNode  = StartNode;
294     ChildNode   = AcpiNsGetNextNode (ParentNode, NULL);
295     ChildType   = ACPI_TYPE_ANY;
296     Level       = 1;
297 
298     /*
299      * Traverse the tree of nodes until we bubble back up to where we
300      * started. When Level is zero, the loop is done because we have
301      * bubbled up to (and passed) the original parent handle (StartEntry)
302      */
303     while (Level > 0 && ChildNode)
304     {
305         Status = AE_OK;
306 
307         /* Found next child, get the type if we are not searching for ANY */
308 
309         if (Type != ACPI_TYPE_ANY)
310         {
311             ChildType = ChildNode->Type;
312         }
313 
314         /*
315          * Ignore all temporary namespace nodes (created during control
316          * method execution) unless told otherwise. These temporary nodes
317          * can cause a race condition because they can be deleted during
318          * the execution of the user function (if the namespace is
319          * unlocked before invocation of the user function.) Only the
320          * debugger namespace dump will examine the temporary nodes.
321          */
322         if ((ChildNode->Flags & ANOBJ_TEMPORARY) &&
323             !(Flags & ACPI_NS_WALK_TEMP_NODES))
324         {
325             Status = AE_CTRL_DEPTH;
326         }
327 
328         /* Type must match requested type */
329 
330         else if (ChildType == Type)
331         {
332             /*
333              * Found a matching node, invoke the user callback function.
334              * Unlock the namespace if flag is set.
335              */
336             if (Flags & ACPI_NS_WALK_UNLOCK)
337             {
338                 MutexStatus = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
339                 if (ACPI_FAILURE (MutexStatus))
340                 {
341                     return_ACPI_STATUS (MutexStatus);
342                 }
343             }
344 
345             /*
346              * Invoke the user function, either descending, ascending,
347              * or both.
348              */
349             if (!NodePreviouslyVisited)
350             {
351                 if (DescendingCallback)
352                 {
353                     Status = DescendingCallback (ChildNode, Level,
354                                 Context, ReturnValue);
355                 }
356             }
357             else
358             {
359                 if (AscendingCallback)
360                 {
361                     Status = AscendingCallback (ChildNode, Level,
362                                 Context, ReturnValue);
363                 }
364             }
365 
366             if (Flags & ACPI_NS_WALK_UNLOCK)
367             {
368                 MutexStatus = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
369                 if (ACPI_FAILURE (MutexStatus))
370                 {
371                     return_ACPI_STATUS (MutexStatus);
372                 }
373             }
374 
375             switch (Status)
376             {
377             case AE_OK:
378             case AE_CTRL_DEPTH:
379 
380                 /* Just keep going */
381                 break;
382 
383             case AE_CTRL_TERMINATE:
384 
385                 /* Exit now, with OK status */
386 
387                 return_ACPI_STATUS (AE_OK);
388 
389             default:
390 
391                 /* All others are valid exceptions */
392 
393                 return_ACPI_STATUS (Status);
394             }
395         }
396 
397         /*
398          * Depth first search: Attempt to go down another level in the
399          * namespace if we are allowed to. Don't go any further if we have
400          * reached the caller specified maximum depth or if the user
401          * function has specified that the maximum depth has been reached.
402          */
403         if (!NodePreviouslyVisited &&
404             (Level < MaxDepth) &&
405             (Status != AE_CTRL_DEPTH))
406         {
407             if (ChildNode->Child)
408             {
409                 /* There is at least one child of this node, visit it */
410 
411                 Level++;
412                 ParentNode = ChildNode;
413                 ChildNode = AcpiNsGetNextNode (ParentNode, NULL);
414                 continue;
415             }
416         }
417 
418         /* No more children, re-visit this node */
419 
420         if (!NodePreviouslyVisited)
421         {
422             NodePreviouslyVisited = TRUE;
423             continue;
424         }
425 
426         /* No more children, visit peers */
427 
428         ChildNode = AcpiNsGetNextNode (ParentNode, ChildNode);
429         if (ChildNode)
430         {
431             NodePreviouslyVisited = FALSE;
432         }
433 
434         /* No peers, re-visit parent */
435 
436         else
437         {
438             /*
439              * No more children of this node (AcpiNsGetNextNode failed), go
440              * back upwards in the namespace tree to the node's parent.
441              */
442             Level--;
443             ChildNode = ParentNode;
444             ParentNode = ParentNode->Parent;
445 
446             NodePreviouslyVisited = TRUE;
447         }
448     }
449 
450     /* Complete walk, not terminated by user function */
451 
452     return_ACPI_STATUS (AE_OK);
453 }
454