xref: /titanic_41/usr/src/uts/intel/io/acpica/namespace/nsnames.c (revision c28afb19581b550bf02e148f953e3b239421e1ee)
1 /*******************************************************************************
2  *
3  * Module Name: nsnames - Name manipulation and search
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2011, 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 __NSNAMES_C__
45 
46 #include "acpi.h"
47 #include "accommon.h"
48 #include "amlcode.h"
49 #include "acnamesp.h"
50 
51 
52 #define _COMPONENT          ACPI_NAMESPACE
53         ACPI_MODULE_NAME    ("nsnames")
54 
55 
56 /*******************************************************************************
57  *
58  * FUNCTION:    AcpiNsBuildExternalPath
59  *
60  * PARAMETERS:  Node            - NS node whose pathname is needed
61  *              Size            - Size of the pathname
62  *              *NameBuffer     - Where to return the pathname
63  *
64  * RETURN:      Status
65  *              Places the pathname into the NameBuffer, in external format
66  *              (name segments separated by path separators)
67  *
68  * DESCRIPTION: Generate a full pathaname
69  *
70  ******************************************************************************/
71 
72 ACPI_STATUS
73 AcpiNsBuildExternalPath (
74     ACPI_NAMESPACE_NODE     *Node,
75     ACPI_SIZE               Size,
76     char                    *NameBuffer)
77 {
78     ACPI_SIZE               Index;
79     ACPI_NAMESPACE_NODE     *ParentNode;
80 
81 
82     ACPI_FUNCTION_ENTRY ();
83 
84 
85     /* Special case for root */
86 
87     Index = Size - 1;
88     if (Index < ACPI_NAME_SIZE)
89     {
90         NameBuffer[0] = AML_ROOT_PREFIX;
91         NameBuffer[1] = 0;
92         return (AE_OK);
93     }
94 
95     /* Store terminator byte, then build name backwards */
96 
97     ParentNode = Node;
98     NameBuffer[Index] = 0;
99 
100     while ((Index > ACPI_NAME_SIZE) && (ParentNode != AcpiGbl_RootNode))
101     {
102         Index -= ACPI_NAME_SIZE;
103 
104         /* Put the name into the buffer */
105 
106         ACPI_MOVE_32_TO_32 ((NameBuffer + Index), &ParentNode->Name);
107         ParentNode = ParentNode->Parent;
108 
109         /* Prefix name with the path separator */
110 
111         Index--;
112         NameBuffer[Index] = ACPI_PATH_SEPARATOR;
113     }
114 
115     /* Overwrite final separator with the root prefix character */
116 
117     NameBuffer[Index] = AML_ROOT_PREFIX;
118 
119     if (Index != 0)
120     {
121         ACPI_ERROR ((AE_INFO,
122             "Could not construct external pathname; index=%u, size=%u, Path=%s",
123             (UINT32) Index, (UINT32) Size, &NameBuffer[Size]));
124 
125         return (AE_BAD_PARAMETER);
126     }
127 
128     return (AE_OK);
129 }
130 
131 
132 /*******************************************************************************
133  *
134  * FUNCTION:    AcpiNsGetExternalPathname
135  *
136  * PARAMETERS:  Node            - Namespace node whose pathname is needed
137  *
138  * RETURN:      Pointer to storage containing the fully qualified name of
139  *              the node, In external format (name segments separated by path
140  *              separators.)
141  *
142  * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
143  *              for error and debug statements.
144  *
145  ******************************************************************************/
146 
147 char *
148 AcpiNsGetExternalPathname (
149     ACPI_NAMESPACE_NODE     *Node)
150 {
151     ACPI_STATUS             Status;
152     char                    *NameBuffer;
153     ACPI_SIZE               Size;
154 
155 
156     ACPI_FUNCTION_TRACE_PTR (NsGetExternalPathname, Node);
157 
158 
159     /* Calculate required buffer size based on depth below root */
160 
161     Size = AcpiNsGetPathnameLength (Node);
162     if (!Size)
163     {
164         return_PTR (NULL);
165     }
166 
167     /* Allocate a buffer to be returned to caller */
168 
169     NameBuffer = ACPI_ALLOCATE_ZEROED (Size);
170     if (!NameBuffer)
171     {
172         ACPI_ERROR ((AE_INFO, "Could not allocate %u bytes", (UINT32) Size));
173         return_PTR (NULL);
174     }
175 
176     /* Build the path in the allocated buffer */
177 
178     Status = AcpiNsBuildExternalPath (Node, Size, NameBuffer);
179     if (ACPI_FAILURE (Status))
180     {
181         ACPI_FREE (NameBuffer);
182         return_PTR (NULL);
183     }
184 
185     return_PTR (NameBuffer);
186 }
187 
188 
189 /*******************************************************************************
190  *
191  * FUNCTION:    AcpiNsGetPathnameLength
192  *
193  * PARAMETERS:  Node        - Namespace node
194  *
195  * RETURN:      Length of path, including prefix
196  *
197  * DESCRIPTION: Get the length of the pathname string for this node
198  *
199  ******************************************************************************/
200 
201 ACPI_SIZE
202 AcpiNsGetPathnameLength (
203     ACPI_NAMESPACE_NODE     *Node)
204 {
205     ACPI_SIZE               Size;
206     ACPI_NAMESPACE_NODE     *NextNode;
207 
208 
209     ACPI_FUNCTION_ENTRY ();
210 
211 
212     /*
213      * Compute length of pathname as 5 * number of name segments.
214      * Go back up the parent tree to the root
215      */
216     Size = 0;
217     NextNode = Node;
218 
219     while (NextNode && (NextNode != AcpiGbl_RootNode))
220     {
221         if (ACPI_GET_DESCRIPTOR_TYPE (NextNode) != ACPI_DESC_TYPE_NAMED)
222         {
223             ACPI_ERROR ((AE_INFO,
224                 "Invalid Namespace Node (%p) while traversing namespace",
225                 NextNode));
226             return 0;
227         }
228         Size += ACPI_PATH_SEGMENT_LENGTH;
229         NextNode = NextNode->Parent;
230     }
231 
232     if (!Size)
233     {
234         Size = 1; /* Root node case */
235     }
236 
237     return (Size + 1);  /* +1 for null string terminator */
238 }
239 
240 
241 /*******************************************************************************
242  *
243  * FUNCTION:    AcpiNsHandleToPathname
244  *
245  * PARAMETERS:  TargetHandle            - Handle of named object whose name is
246  *                                        to be found
247  *              Buffer                  - Where the pathname is returned
248  *
249  * RETURN:      Status, Buffer is filled with pathname if status is AE_OK
250  *
251  * DESCRIPTION: Build and return a full namespace pathname
252  *
253  ******************************************************************************/
254 
255 ACPI_STATUS
256 AcpiNsHandleToPathname (
257     ACPI_HANDLE             TargetHandle,
258     ACPI_BUFFER             *Buffer)
259 {
260     ACPI_STATUS             Status;
261     ACPI_NAMESPACE_NODE     *Node;
262     ACPI_SIZE               RequiredSize;
263 
264 
265     ACPI_FUNCTION_TRACE_PTR (NsHandleToPathname, TargetHandle);
266 
267 
268     Node = AcpiNsValidateHandle (TargetHandle);
269     if (!Node)
270     {
271         return_ACPI_STATUS (AE_BAD_PARAMETER);
272     }
273 
274     /* Determine size required for the caller buffer */
275 
276     RequiredSize = AcpiNsGetPathnameLength (Node);
277     if (!RequiredSize)
278     {
279         return_ACPI_STATUS (AE_BAD_PARAMETER);
280     }
281 
282     /* Validate/Allocate/Clear caller buffer */
283 
284     Status = AcpiUtInitializeBuffer (Buffer, RequiredSize);
285     if (ACPI_FAILURE (Status))
286     {
287         return_ACPI_STATUS (Status);
288     }
289 
290     /* Build the path in the caller buffer */
291 
292     Status = AcpiNsBuildExternalPath (Node, RequiredSize, Buffer->Pointer);
293     if (ACPI_FAILURE (Status))
294     {
295         return_ACPI_STATUS (Status);
296     }
297 
298     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%s [%X]\n",
299         (char *) Buffer->Pointer, (UINT32) RequiredSize));
300     return_ACPI_STATUS (AE_OK);
301 }
302 
303 
304