xref: /titanic_41/usr/src/uts/intel/io/acpica/namespace/nswalk.c (revision bf56214c0556fa6864189c826d39dbe156bb22a0)
1 /******************************************************************************
2  *
3  * Module Name: nswalk - Functions for walking the ACPI namespace
4  *              $Revision: 1.41 $
5  *
6  *****************************************************************************/
7 
8 /******************************************************************************
9  *
10  * 1. Copyright Notice
11  *
12  * Some or all of this work - Copyright (c) 1999 - 2006, Intel Corp.
13  * All rights reserved.
14  *
15  * 2. License
16  *
17  * 2.1. This is your license from Intel Corp. under its intellectual property
18  * rights.  You may have additional license terms from the party that provided
19  * you this software, covering your right to use that party's intellectual
20  * property rights.
21  *
22  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
23  * copy of the source code appearing in this file ("Covered Code") an
24  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
25  * base code distributed originally by Intel ("Original Intel Code") to copy,
26  * make derivatives, distribute, use and display any portion of the Covered
27  * Code in any form, with the right to sublicense such rights; and
28  *
29  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
30  * license (with the right to sublicense), under only those claims of Intel
31  * patents that are infringed by the Original Intel Code, to make, use, sell,
32  * offer to sell, and import the Covered Code and derivative works thereof
33  * solely to the minimum extent necessary to exercise the above copyright
34  * license, and in no event shall the patent license extend to any additions
35  * to or modifications of the Original Intel Code.  No other license or right
36  * is granted directly or by implication, estoppel or otherwise;
37  *
38  * The above copyright and patent license is granted only if the following
39  * conditions are met:
40  *
41  * 3. Conditions
42  *
43  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
44  * Redistribution of source code of any substantial portion of the Covered
45  * Code or modification with rights to further distribute source must include
46  * the above Copyright Notice, the above License, this list of Conditions,
47  * and the following Disclaimer and Export Compliance provision.  In addition,
48  * Licensee must cause all Covered Code to which Licensee contributes to
49  * contain a file documenting the changes Licensee made to create that Covered
50  * Code and the date of any change.  Licensee must include in that file the
51  * documentation of any changes made by any predecessor Licensee.  Licensee
52  * must include a prominent statement that the modification is derived,
53  * directly or indirectly, from Original Intel Code.
54  *
55  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
56  * Redistribution of source code of any substantial portion of the Covered
57  * Code or modification without rights to further distribute source must
58  * include the following Disclaimer and Export Compliance provision in the
59  * documentation and/or other materials provided with distribution.  In
60  * addition, Licensee may not authorize further sublicense of source of any
61  * portion of the Covered Code, and must include terms to the effect that the
62  * license from Licensee to its licensee is limited to the intellectual
63  * property embodied in the software Licensee provides to its licensee, and
64  * not to intellectual property embodied in modifications its licensee may
65  * make.
66  *
67  * 3.3. Redistribution of Executable. Redistribution in executable form of any
68  * substantial portion of the Covered Code or modification must reproduce the
69  * above Copyright Notice, and the following Disclaimer and Export Compliance
70  * provision in the documentation and/or other materials provided with the
71  * distribution.
72  *
73  * 3.4. Intel retains all right, title, and interest in and to the Original
74  * Intel Code.
75  *
76  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
77  * Intel shall be used in advertising or otherwise to promote the sale, use or
78  * other dealings in products derived from or relating to the Covered Code
79  * without prior written authorization from Intel.
80  *
81  * 4. Disclaimer and Export Compliance
82  *
83  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
84  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
85  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
86  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
87  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
88  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
89  * PARTICULAR PURPOSE.
90  *
91  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
92  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
93  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
94  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
95  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
96  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
97  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
98  * LIMITED REMEDY.
99  *
100  * 4.3. Licensee shall not export, either directly or indirectly, any of this
101  * software or system incorporating such software without first obtaining any
102  * required license or other approval from the U. S. Department of Commerce or
103  * any other agency or department of the United States Government.  In the
104  * event Licensee exports any such software from the United States or
105  * re-exports any such software from a foreign destination, Licensee shall
106  * ensure that the distribution and export/re-export of the software is in
107  * compliance with all laws, regulations, orders, or other restrictions of the
108  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
109  * any of its subsidiaries will export/re-export any technical data, process,
110  * software, or service, directly or indirectly, to any country for which the
111  * United States government or any agency thereof requires an export license,
112  * other governmental approval, or letter of assurance, without first obtaining
113  * such license, approval or letter.
114  *
115  *****************************************************************************/
116 
117 
118 #define __NSWALK_C__
119 
120 #include "acpi.h"
121 #include "acnamesp.h"
122 
123 
124 #define _COMPONENT          ACPI_NAMESPACE
125         ACPI_MODULE_NAME    ("nswalk")
126 
127 
128 /*******************************************************************************
129  *
130  * FUNCTION:    AcpiNsGetNextNode
131  *
132  * PARAMETERS:  Type                - Type of node to be searched for
133  *              ParentNode          - Parent node whose children we are
134  *                                    getting
135  *              ChildNode           - Previous child that was found.
136  *                                    The NEXT child will be returned
137  *
138  * RETURN:      ACPI_NAMESPACE_NODE - Pointer to the NEXT child or NULL if
139  *                                    none is found.
140  *
141  * DESCRIPTION: Return the next peer node within the namespace.  If Handle
142  *              is valid, Scope is ignored.  Otherwise, the first node
143  *              within Scope is returned.
144  *
145  ******************************************************************************/
146 
147 ACPI_NAMESPACE_NODE *
148 AcpiNsGetNextNode (
149     ACPI_OBJECT_TYPE        Type,
150     ACPI_NAMESPACE_NODE     *ParentNode,
151     ACPI_NAMESPACE_NODE     *ChildNode)
152 {
153     ACPI_NAMESPACE_NODE     *NextNode = NULL;
154 
155 
156     ACPI_FUNCTION_ENTRY ();
157 
158 
159     if (!ChildNode)
160     {
161         /* It's really the parent's _scope_ that we want */
162 
163         if (ParentNode->Child)
164         {
165             NextNode = ParentNode->Child;
166         }
167     }
168 
169     else
170     {
171         /* Start search at the NEXT node */
172 
173         NextNode = AcpiNsGetNextValidNode (ChildNode);
174     }
175 
176     /* If any type is OK, we are done */
177 
178     if (Type == ACPI_TYPE_ANY)
179     {
180         /* NextNode is NULL if we are at the end-of-list */
181 
182         return (NextNode);
183     }
184 
185     /* Must search for the node -- but within this scope only */
186 
187     while (NextNode)
188     {
189         /* If type matches, we are done */
190 
191         if (NextNode->Type == Type)
192         {
193             return (NextNode);
194         }
195 
196         /* Otherwise, move on to the next node */
197 
198         NextNode = AcpiNsGetNextValidNode (NextNode);
199     }
200 
201     /* Not found */
202 
203     return (NULL);
204 }
205 
206 
207 /*******************************************************************************
208  *
209  * FUNCTION:    AcpiNsWalkNamespace
210  *
211  * PARAMETERS:  Type                - ACPI_OBJECT_TYPE to search for
212  *              StartNode           - Handle in namespace where search begins
213  *              MaxDepth            - Depth to which search is to reach
214  *              UnlockBeforeCallback- Whether to unlock the NS before invoking
215  *                                    the callback routine
216  *              UserFunction        - Called when an object of "Type" is found
217  *              Context             - Passed to user function
218  *              ReturnValue         - from the UserFunction if terminated early.
219  *                                    Otherwise, returns NULL.
220  * RETURNS:     Status
221  *
222  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
223  *              starting (and ending) at the node specified by StartHandle.
224  *              The UserFunction is called whenever a node that matches
225  *              the type parameter is found.  If the user function returns
226  *              a non-zero value, the search is terminated immediately and this
227  *              value is returned to the caller.
228  *
229  *              The point of this procedure is to provide a generic namespace
230  *              walk routine that can be called from multiple places to
231  *              provide multiple services;  the User Function can be tailored
232  *              to each task, whether it is a print function, a compare
233  *              function, etc.
234  *
235  ******************************************************************************/
236 
237 ACPI_STATUS
238 AcpiNsWalkNamespace (
239     ACPI_OBJECT_TYPE        Type,
240     ACPI_HANDLE             StartNode,
241     UINT32                  MaxDepth,
242     BOOLEAN                 UnlockBeforeCallback,
243     ACPI_WALK_CALLBACK      UserFunction,
244     void                    *Context,
245     void                    **ReturnValue)
246 {
247     ACPI_STATUS             Status;
248     ACPI_STATUS             MutexStatus;
249     ACPI_NAMESPACE_NODE     *ChildNode;
250     ACPI_NAMESPACE_NODE     *ParentNode;
251     ACPI_OBJECT_TYPE        ChildType;
252     UINT32                  Level;
253 
254 
255     ACPI_FUNCTION_TRACE (NsWalkNamespace);
256 
257 
258     /* Special case for the namespace Root Node */
259 
260     if (StartNode == ACPI_ROOT_OBJECT)
261     {
262         StartNode = AcpiGbl_RootNode;
263     }
264 
265     /* Null child means "get first node" */
266 
267     ParentNode  = StartNode;
268     ChildNode   = NULL;
269     ChildType   = ACPI_TYPE_ANY;
270     Level       = 1;
271 
272     /*
273      * Traverse the tree of nodes until we bubble back up to where we
274      * started. When Level is zero, the loop is done because we have
275      * bubbled up to (and passed) the original parent handle (StartEntry)
276      */
277     while (Level > 0)
278     {
279         /* Get the next node in this scope.  Null if not found */
280 
281         Status = AE_OK;
282         ChildNode = AcpiNsGetNextNode (ACPI_TYPE_ANY, ParentNode, ChildNode);
283         if (ChildNode)
284         {
285             /*
286              * Found node, Get the type if we are not
287              * searching for ANY
288              */
289             if (Type != ACPI_TYPE_ANY)
290             {
291                 ChildType = ChildNode->Type;
292             }
293 
294             if (ChildType == Type)
295             {
296                 /*
297                  * Found a matching node, invoke the user
298                  * callback function
299                  */
300                 if (UnlockBeforeCallback)
301                 {
302                     MutexStatus = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
303                     if (ACPI_FAILURE (MutexStatus))
304                     {
305                         return_ACPI_STATUS (MutexStatus);
306                     }
307                 }
308 
309                 Status = UserFunction (ChildNode, Level,
310                                         Context, ReturnValue);
311 
312                 if (UnlockBeforeCallback)
313                 {
314                     MutexStatus = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
315                     if (ACPI_FAILURE (MutexStatus))
316                     {
317                         return_ACPI_STATUS (MutexStatus);
318                     }
319                 }
320 
321                 switch (Status)
322                 {
323                 case AE_OK:
324                 case AE_CTRL_DEPTH:
325 
326                     /* Just keep going */
327                     break;
328 
329                 case AE_CTRL_TERMINATE:
330 
331                     /* Exit now, with OK status */
332 
333                     return_ACPI_STATUS (AE_OK);
334 
335                 default:
336 
337                     /* All others are valid exceptions */
338 
339                     return_ACPI_STATUS (Status);
340                 }
341             }
342 
343             /*
344              * Depth first search:
345              * Attempt to go down another level in the namespace
346              * if we are allowed to.  Don't go any further if we
347              * have reached the caller specified maximum depth
348              * or if the user function has specified that the
349              * maximum depth has been reached.
350              */
351             if ((Level < MaxDepth) && (Status != AE_CTRL_DEPTH))
352             {
353                 if (AcpiNsGetNextNode (ACPI_TYPE_ANY, ChildNode, NULL))
354                 {
355                     /*
356                      * There is at least one child of this
357                      * node, visit the onde
358                      */
359                     Level++;
360                     ParentNode = ChildNode;
361                     ChildNode  = NULL;
362                 }
363             }
364         }
365         else
366         {
367             /*
368              * No more children of this node (AcpiNsGetNextNode
369              * failed), go back upwards in the namespace tree to
370              * the node's parent.
371              */
372             Level--;
373             ChildNode = ParentNode;
374             ParentNode = AcpiNsGetParentNode (ParentNode);
375         }
376     }
377 
378     /* Complete walk, not terminated by user function */
379 
380     return_ACPI_STATUS (AE_OK);
381 }
382 
383 
384