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 - 2018, 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 * Alternatively, you may choose to be licensed under the terms of the
117 * following license:
118 *
119 * Redistribution and use in source and binary forms, with or without
120 * modification, are permitted provided that the following conditions
121 * are met:
122 * 1. Redistributions of source code must retain the above copyright
123 *    notice, this list of conditions, and the following disclaimer,
124 *    without modification.
125 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126 *    substantially similar to the "NO WARRANTY" disclaimer below
127 *    ("Disclaimer") and any redistribution must be conditioned upon
128 *    including a substantially similar Disclaimer requirement for further
129 *    binary redistribution.
130 * 3. Neither the names of the above-listed copyright holders nor the names
131 *    of any contributors may be used to endorse or promote products derived
132 *    from this software without specific prior written permission.
133 *
134 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145 *
146 * Alternatively, you may choose to be licensed under the terms of the
147 * GNU General Public License ("GPL") version 2 as published by the Free
148 * Software Foundation.
149 *
150 *****************************************************************************/
151
152#include "acpi.h"
153#include "accommon.h"
154#include "acnamesp.h"
155
156
157#define _COMPONENT          ACPI_NAMESPACE
158        ACPI_MODULE_NAME    ("nswalk")
159
160
161/*******************************************************************************
162 *
163 * FUNCTION:    AcpiNsGetNextNode
164 *
165 * PARAMETERS:  ParentNode          - Parent node whose children we are
166 *                                    getting
167 *              ChildNode           - Previous child that was found.
168 *                                    The NEXT child will be returned
169 *
170 * RETURN:      ACPI_NAMESPACE_NODE - Pointer to the NEXT child or NULL if
171 *                                    none is found.
172 *
173 * DESCRIPTION: Return the next peer node within the namespace. If Handle
174 *              is valid, Scope is ignored. Otherwise, the first node
175 *              within Scope is returned.
176 *
177 ******************************************************************************/
178
179ACPI_NAMESPACE_NODE *
180AcpiNsGetNextNode (
181    ACPI_NAMESPACE_NODE     *ParentNode,
182    ACPI_NAMESPACE_NODE     *ChildNode)
183{
184    ACPI_FUNCTION_ENTRY ();
185
186
187    if (!ChildNode)
188    {
189        /* It's really the parent's _scope_ that we want */
190
191        return (ParentNode->Child);
192    }
193
194    /* Otherwise just return the next peer */
195
196    return (ChildNode->Peer);
197}
198
199
200/*******************************************************************************
201 *
202 * FUNCTION:    AcpiNsGetNextNodeTyped
203 *
204 * PARAMETERS:  Type                - Type of node to be searched for
205 *              ParentNode          - Parent node whose children we are
206 *                                    getting
207 *              ChildNode           - Previous child that was found.
208 *                                    The NEXT child will be returned
209 *
210 * RETURN:      ACPI_NAMESPACE_NODE - Pointer to the NEXT child or NULL if
211 *                                    none is found.
212 *
213 * DESCRIPTION: Return the next peer node within the namespace. If Handle
214 *              is valid, Scope is ignored. Otherwise, the first node
215 *              within Scope is returned.
216 *
217 ******************************************************************************/
218
219ACPI_NAMESPACE_NODE *
220AcpiNsGetNextNodeTyped (
221    ACPI_OBJECT_TYPE        Type,
222    ACPI_NAMESPACE_NODE     *ParentNode,
223    ACPI_NAMESPACE_NODE     *ChildNode)
224{
225    ACPI_NAMESPACE_NODE     *NextNode = NULL;
226
227
228    ACPI_FUNCTION_ENTRY ();
229
230
231    NextNode = AcpiNsGetNextNode (ParentNode, ChildNode);
232
233    /* If any type is OK, we are done */
234
235    if (Type == ACPI_TYPE_ANY)
236    {
237        /* NextNode is NULL if we are at the end-of-list */
238
239        return (NextNode);
240    }
241
242    /* Must search for the node -- but within this scope only */
243
244    while (NextNode)
245    {
246        /* If type matches, we are done */
247
248        if (NextNode->Type == Type)
249        {
250            return (NextNode);
251        }
252
253        /* Otherwise, move on to the next peer node */
254
255        NextNode = NextNode->Peer;
256    }
257
258    /* Not found */
259
260    return (NULL);
261}
262
263
264/*******************************************************************************
265 *
266 * FUNCTION:    AcpiNsWalkNamespace
267 *
268 * PARAMETERS:  Type                - ACPI_OBJECT_TYPE to search for
269 *              StartNode           - Handle in namespace where search begins
270 *              MaxDepth            - Depth to which search is to reach
271 *              Flags               - Whether to unlock the NS before invoking
272 *                                    the callback routine
273 *              DescendingCallback  - Called during tree descent
274 *                                    when an object of "Type" is found
275 *              AscendingCallback   - Called during tree ascent
276 *                                    when an object of "Type" is found
277 *              Context             - Passed to user function(s) above
278 *              ReturnValue         - from the UserFunction if terminated
279 *                                    early. Otherwise, returns NULL.
280 * RETURNS:     Status
281 *
282 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
283 *              starting (and ending) at the node specified by StartHandle.
284 *              The callback function is called whenever a node that matches
285 *              the type parameter is found. If the callback function returns
286 *              a non-zero value, the search is terminated immediately and
287 *              this value is returned to the caller.
288 *
289 *              The point of this procedure is to provide a generic namespace
290 *              walk routine that can be called from multiple places to
291 *              provide multiple services; the callback function(s) can be
292 *              tailored to each task, whether it is a print function,
293 *              a compare function, etc.
294 *
295 ******************************************************************************/
296
297ACPI_STATUS
298AcpiNsWalkNamespace (
299    ACPI_OBJECT_TYPE        Type,
300    ACPI_HANDLE             StartNode,
301    UINT32                  MaxDepth,
302    UINT32                  Flags,
303    ACPI_WALK_CALLBACK      DescendingCallback,
304    ACPI_WALK_CALLBACK      AscendingCallback,
305    void                    *Context,
306    void                    **ReturnValue)
307{
308    ACPI_STATUS             Status;
309    ACPI_STATUS             MutexStatus;
310    ACPI_NAMESPACE_NODE     *ChildNode;
311    ACPI_NAMESPACE_NODE     *ParentNode;
312    ACPI_OBJECT_TYPE        ChildType;
313    UINT32                  Level;
314    BOOLEAN                 NodePreviouslyVisited = FALSE;
315
316
317    ACPI_FUNCTION_TRACE (NsWalkNamespace);
318
319
320    /* Special case for the namespace Root Node */
321
322    if (StartNode == ACPI_ROOT_OBJECT)
323    {
324        StartNode = AcpiGbl_RootNode;
325    }
326
327    /* Null child means "get first node" */
328
329    ParentNode = StartNode;
330    ChildNode = AcpiNsGetNextNode (ParentNode, NULL);
331    ChildType = ACPI_TYPE_ANY;
332    Level = 1;
333
334    /*
335     * Traverse the tree of nodes until we bubble back up to where we
336     * started. When Level is zero, the loop is done because we have
337     * bubbled up to (and passed) the original parent handle (StartEntry)
338     */
339    while (Level > 0 && ChildNode)
340    {
341        Status = AE_OK;
342
343        /* Found next child, get the type if we are not searching for ANY */
344
345        if (Type != ACPI_TYPE_ANY)
346        {
347            ChildType = ChildNode->Type;
348        }
349
350        /*
351         * Ignore all temporary namespace nodes (created during control
352         * method execution) unless told otherwise. These temporary nodes
353         * can cause a race condition because they can be deleted during
354         * the execution of the user function (if the namespace is
355         * unlocked before invocation of the user function.) Only the
356         * debugger namespace dump will examine the temporary nodes.
357         */
358        if ((ChildNode->Flags & ANOBJ_TEMPORARY) &&
359            !(Flags & ACPI_NS_WALK_TEMP_NODES))
360        {
361            Status = AE_CTRL_DEPTH;
362        }
363
364        /* Type must match requested type */
365
366        else if (ChildType == Type)
367        {
368            /*
369             * Found a matching node, invoke the user callback function.
370             * Unlock the namespace if flag is set.
371             */
372            if (Flags & ACPI_NS_WALK_UNLOCK)
373            {
374                MutexStatus = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
375                if (ACPI_FAILURE (MutexStatus))
376                {
377                    return_ACPI_STATUS (MutexStatus);
378                }
379            }
380
381            /*
382             * Invoke the user function, either descending, ascending,
383             * or both.
384             */
385            if (!NodePreviouslyVisited)
386            {
387                if (DescendingCallback)
388                {
389                    Status = DescendingCallback (ChildNode, Level,
390                        Context, ReturnValue);
391                }
392            }
393            else
394            {
395                if (AscendingCallback)
396                {
397                    Status = AscendingCallback (ChildNode, Level,
398                        Context, ReturnValue);
399                }
400            }
401
402            if (Flags & ACPI_NS_WALK_UNLOCK)
403            {
404                MutexStatus = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
405                if (ACPI_FAILURE (MutexStatus))
406                {
407                    return_ACPI_STATUS (MutexStatus);
408                }
409            }
410
411            switch (Status)
412            {
413            case AE_OK:
414            case AE_CTRL_DEPTH:
415
416                /* Just keep going */
417                break;
418
419            case AE_CTRL_TERMINATE:
420
421                /* Exit now, with OK status */
422
423                return_ACPI_STATUS (AE_OK);
424
425            default:
426
427                /* All others are valid exceptions */
428
429                return_ACPI_STATUS (Status);
430            }
431        }
432
433        /*
434         * Depth first search: Attempt to go down another level in the
435         * namespace if we are allowed to. Don't go any further if we have
436         * reached the caller specified maximum depth or if the user
437         * function has specified that the maximum depth has been reached.
438         */
439        if (!NodePreviouslyVisited &&
440            (Level < MaxDepth) &&
441            (Status != AE_CTRL_DEPTH))
442        {
443            if (ChildNode->Child)
444            {
445                /* There is at least one child of this node, visit it */
446
447                Level++;
448                ParentNode = ChildNode;
449                ChildNode = AcpiNsGetNextNode (ParentNode, NULL);
450                continue;
451            }
452        }
453
454        /* No more children, re-visit this node */
455
456        if (!NodePreviouslyVisited)
457        {
458            NodePreviouslyVisited = TRUE;
459            continue;
460        }
461
462        /* No more children, visit peers */
463
464        ChildNode = AcpiNsGetNextNode (ParentNode, ChildNode);
465        if (ChildNode)
466        {
467            NodePreviouslyVisited = FALSE;
468        }
469
470        /* No peers, re-visit parent */
471
472        else
473        {
474            /*
475             * No more children of this node (AcpiNsGetNextNode failed), go
476             * back upwards in the namespace tree to the node's parent.
477             */
478            Level--;
479            ChildNode = ParentNode;
480            ParentNode = ParentNode->Parent;
481
482            NodePreviouslyVisited = TRUE;
483        }
484    }
485
486    /* Complete walk, not terminated by user function */
487
488    return_ACPI_STATUS (AE_OK);
489}
490