Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / drivers / acpi / acpica / exstorob.c
1
2 /******************************************************************************
3  *
4  * Module Name: exstorob - AML Interpreter object store support, store to object
5  *
6  *****************************************************************************/
7
8 /*
9  * Copyright (C) 2000 - 2012, Intel Corp.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions, and the following disclaimer,
17  *    without modification.
18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19  *    substantially similar to the "NO WARRANTY" disclaimer below
20  *    ("Disclaimer") and any redistribution must be conditioned upon
21  *    including a substantially similar Disclaimer requirement for further
22  *    binary redistribution.
23  * 3. Neither the names of the above-listed copyright holders nor the names
24  *    of any contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * Alternatively, this software may be distributed under the terms of the
28  * GNU General Public License ("GPL") version 2 as published by the Free
29  * Software Foundation.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44
45 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "acinterp.h"
48
49 #define _COMPONENT          ACPI_EXECUTER
50 ACPI_MODULE_NAME("exstorob")
51
52 /*******************************************************************************
53  *
54  * FUNCTION:    acpi_ex_store_buffer_to_buffer
55  *
56  * PARAMETERS:  source_desc         - Source object to copy
57  *              target_desc         - Destination object of the copy
58  *
59  * RETURN:      Status
60  *
61  * DESCRIPTION: Copy a buffer object to another buffer object.
62  *
63  ******************************************************************************/
64 acpi_status
65 acpi_ex_store_buffer_to_buffer(union acpi_operand_object *source_desc,
66                                union acpi_operand_object *target_desc)
67 {
68         u32 length;
69         u8 *buffer;
70
71         ACPI_FUNCTION_TRACE_PTR(ex_store_buffer_to_buffer, source_desc);
72
73         /* If Source and Target are the same, just return */
74
75         if (source_desc == target_desc) {
76                 return_ACPI_STATUS(AE_OK);
77         }
78
79         /* We know that source_desc is a buffer by now */
80
81         buffer = ACPI_CAST_PTR(u8, source_desc->buffer.pointer);
82         length = source_desc->buffer.length;
83
84         /*
85          * If target is a buffer of length zero or is a static buffer,
86          * allocate a new buffer of the proper length
87          */
88         if ((target_desc->buffer.length == 0) ||
89             (target_desc->common.flags & AOPOBJ_STATIC_POINTER)) {
90                 target_desc->buffer.pointer = ACPI_ALLOCATE(length);
91                 if (!target_desc->buffer.pointer) {
92                         return_ACPI_STATUS(AE_NO_MEMORY);
93                 }
94
95                 target_desc->buffer.length = length;
96         }
97
98         /* Copy source buffer to target buffer */
99
100         if (length <= target_desc->buffer.length) {
101
102                 /* Clear existing buffer and copy in the new one */
103
104                 ACPI_MEMSET(target_desc->buffer.pointer, 0,
105                             target_desc->buffer.length);
106                 ACPI_MEMCPY(target_desc->buffer.pointer, buffer, length);
107
108 #ifdef ACPI_OBSOLETE_BEHAVIOR
109                 /*
110                  * NOTE: ACPI versions up to 3.0 specified that the buffer must be
111                  * truncated if the string is smaller than the buffer.  However, "other"
112                  * implementations of ACPI never did this and thus became the defacto
113                  * standard. ACPI 3.0_a changes this behavior such that the buffer
114                  * is no longer truncated.
115                  */
116
117                 /*
118                  * OBSOLETE BEHAVIOR:
119                  * If the original source was a string, we must truncate the buffer,
120                  * according to the ACPI spec.  Integer-to-Buffer and Buffer-to-Buffer
121                  * copy must not truncate the original buffer.
122                  */
123                 if (original_src_type == ACPI_TYPE_STRING) {
124
125                         /* Set the new length of the target */
126
127                         target_desc->buffer.length = length;
128                 }
129 #endif
130         } else {
131                 /* Truncate the source, copy only what will fit */
132
133                 ACPI_MEMCPY(target_desc->buffer.pointer, buffer,
134                             target_desc->buffer.length);
135
136                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
137                                   "Truncating source buffer from %X to %X\n",
138                                   length, target_desc->buffer.length));
139         }
140
141         /* Copy flags */
142
143         target_desc->buffer.flags = source_desc->buffer.flags;
144         target_desc->common.flags &= ~AOPOBJ_STATIC_POINTER;
145         return_ACPI_STATUS(AE_OK);
146 }
147
148 /*******************************************************************************
149  *
150  * FUNCTION:    acpi_ex_store_string_to_string
151  *
152  * PARAMETERS:  source_desc         - Source object to copy
153  *              target_desc         - Destination object of the copy
154  *
155  * RETURN:      Status
156  *
157  * DESCRIPTION: Copy a String object to another String object
158  *
159  ******************************************************************************/
160
161 acpi_status
162 acpi_ex_store_string_to_string(union acpi_operand_object *source_desc,
163                                union acpi_operand_object *target_desc)
164 {
165         u32 length;
166         u8 *buffer;
167
168         ACPI_FUNCTION_TRACE_PTR(ex_store_string_to_string, source_desc);
169
170         /* If Source and Target are the same, just return */
171
172         if (source_desc == target_desc) {
173                 return_ACPI_STATUS(AE_OK);
174         }
175
176         /* We know that source_desc is a string by now */
177
178         buffer = ACPI_CAST_PTR(u8, source_desc->string.pointer);
179         length = source_desc->string.length;
180
181         /*
182          * Replace existing string value if it will fit and the string
183          * pointer is not a static pointer (part of an ACPI table)
184          */
185         if ((length < target_desc->string.length) &&
186             (!(target_desc->common.flags & AOPOBJ_STATIC_POINTER))) {
187                 /*
188                  * String will fit in existing non-static buffer.
189                  * Clear old string and copy in the new one
190                  */
191                 ACPI_MEMSET(target_desc->string.pointer, 0,
192                             (acpi_size) target_desc->string.length + 1);
193                 ACPI_MEMCPY(target_desc->string.pointer, buffer, length);
194         } else {
195                 /*
196                  * Free the current buffer, then allocate a new buffer
197                  * large enough to hold the value
198                  */
199                 if (target_desc->string.pointer &&
200                     (!(target_desc->common.flags & AOPOBJ_STATIC_POINTER))) {
201
202                         /* Only free if not a pointer into the DSDT */
203
204                         ACPI_FREE(target_desc->string.pointer);
205                 }
206
207                 target_desc->string.pointer = ACPI_ALLOCATE_ZEROED((acpi_size)
208                                                                    length + 1);
209                 if (!target_desc->string.pointer) {
210                         return_ACPI_STATUS(AE_NO_MEMORY);
211                 }
212
213                 target_desc->common.flags &= ~AOPOBJ_STATIC_POINTER;
214                 ACPI_MEMCPY(target_desc->string.pointer, buffer, length);
215         }
216
217         /* Set the new target length */
218
219         target_desc->string.length = length;
220         return_ACPI_STATUS(AE_OK);
221 }