ia64/kvm: compilation fix. export account_system_vtime.
[pv_ops_mirror.git] / drivers / acpi / namespace / nsnames.c
blobcffef1bcbdbc3dde9db746c19be2314a6bc67d0c
1 /*******************************************************************************
3 * Module Name: nsnames - Name manipulation and search
5 ******************************************************************************/
7 /*
8 * Copyright (C) 2000 - 2008, Intel Corp.
9 * All rights reserved.
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.
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.
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
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36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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41 * POSSIBILITY OF SUCH DAMAGES.
44 #include <acpi/acpi.h>
45 #include <acpi/amlcode.h>
46 #include <acpi/acnamesp.h>
48 #define _COMPONENT ACPI_NAMESPACE
49 ACPI_MODULE_NAME("nsnames")
51 /*******************************************************************************
53 * FUNCTION: acpi_ns_build_external_path
55 * PARAMETERS: Node - NS node whose pathname is needed
56 * Size - Size of the pathname
57 * *name_buffer - Where to return the pathname
59 * RETURN: Places the pathname into the name_buffer, in external format
60 * (name segments separated by path separators)
62 * DESCRIPTION: Generate a full pathaname
64 ******************************************************************************/
65 void
66 acpi_ns_build_external_path(struct acpi_namespace_node *node,
67 acpi_size size, char *name_buffer)
69 acpi_size index;
70 struct acpi_namespace_node *parent_node;
72 ACPI_FUNCTION_ENTRY();
74 /* Special case for root */
76 index = size - 1;
77 if (index < ACPI_NAME_SIZE) {
78 name_buffer[0] = AML_ROOT_PREFIX;
79 name_buffer[1] = 0;
80 return;
83 /* Store terminator byte, then build name backwards */
85 parent_node = node;
86 name_buffer[index] = 0;
88 while ((index > ACPI_NAME_SIZE) && (parent_node != acpi_gbl_root_node)) {
89 index -= ACPI_NAME_SIZE;
91 /* Put the name into the buffer */
93 ACPI_MOVE_32_TO_32((name_buffer + index), &parent_node->name);
94 parent_node = acpi_ns_get_parent_node(parent_node);
96 /* Prefix name with the path separator */
98 index--;
99 name_buffer[index] = ACPI_PATH_SEPARATOR;
102 /* Overwrite final separator with the root prefix character */
104 name_buffer[index] = AML_ROOT_PREFIX;
106 if (index != 0) {
107 ACPI_ERROR((AE_INFO,
108 "Could not construct pathname; index=%X, size=%X, Path=%s",
109 (u32) index, (u32) size, &name_buffer[size]));
112 return;
115 #ifdef ACPI_DEBUG_OUTPUT
116 /*******************************************************************************
118 * FUNCTION: acpi_ns_get_external_pathname
120 * PARAMETERS: Node - Namespace node whose pathname is needed
122 * RETURN: Pointer to storage containing the fully qualified name of
123 * the node, In external format (name segments separated by path
124 * separators.)
126 * DESCRIPTION: Used for debug printing in acpi_ns_search_table().
128 ******************************************************************************/
130 char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node)
132 char *name_buffer;
133 acpi_size size;
135 ACPI_FUNCTION_TRACE_PTR(ns_get_external_pathname, node);
137 /* Calculate required buffer size based on depth below root */
139 size = acpi_ns_get_pathname_length(node);
141 /* Allocate a buffer to be returned to caller */
143 name_buffer = ACPI_ALLOCATE_ZEROED(size);
144 if (!name_buffer) {
145 ACPI_ERROR((AE_INFO, "Allocation failure"));
146 return_PTR(NULL);
149 /* Build the path in the allocated buffer */
151 acpi_ns_build_external_path(node, size, name_buffer);
152 return_PTR(name_buffer);
154 #endif
156 /*******************************************************************************
158 * FUNCTION: acpi_ns_get_pathname_length
160 * PARAMETERS: Node - Namespace node
162 * RETURN: Length of path, including prefix
164 * DESCRIPTION: Get the length of the pathname string for this node
166 ******************************************************************************/
168 acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
170 acpi_size size;
171 struct acpi_namespace_node *next_node;
173 ACPI_FUNCTION_ENTRY();
176 * Compute length of pathname as 5 * number of name segments.
177 * Go back up the parent tree to the root
179 size = 0;
180 next_node = node;
182 while (next_node && (next_node != acpi_gbl_root_node)) {
183 if (ACPI_GET_DESCRIPTOR_TYPE(next_node) != ACPI_DESC_TYPE_NAMED) {
184 ACPI_ERROR((AE_INFO,
185 "Invalid NS Node (%p) while traversing path",
186 next_node));
187 return 0;
189 size += ACPI_PATH_SEGMENT_LENGTH;
190 next_node = acpi_ns_get_parent_node(next_node);
193 if (!size) {
194 size = 1; /* Root node case */
197 return (size + 1); /* +1 for null string terminator */
200 /*******************************************************************************
202 * FUNCTION: acpi_ns_handle_to_pathname
204 * PARAMETERS: target_handle - Handle of named object whose name is
205 * to be found
206 * Buffer - Where the pathname is returned
208 * RETURN: Status, Buffer is filled with pathname if status is AE_OK
210 * DESCRIPTION: Build and return a full namespace pathname
212 ******************************************************************************/
214 acpi_status
215 acpi_ns_handle_to_pathname(acpi_handle target_handle,
216 struct acpi_buffer * buffer)
218 acpi_status status;
219 struct acpi_namespace_node *node;
220 acpi_size required_size;
222 ACPI_FUNCTION_TRACE_PTR(ns_handle_to_pathname, target_handle);
224 node = acpi_ns_map_handle_to_node(target_handle);
225 if (!node) {
226 return_ACPI_STATUS(AE_BAD_PARAMETER);
229 /* Determine size required for the caller buffer */
231 required_size = acpi_ns_get_pathname_length(node);
233 /* Validate/Allocate/Clear caller buffer */
235 status = acpi_ut_initialize_buffer(buffer, required_size);
236 if (ACPI_FAILURE(status)) {
237 return_ACPI_STATUS(status);
240 /* Build the path in the caller buffer */
242 acpi_ns_build_external_path(node, required_size, buffer->pointer);
244 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s [%X]\n",
245 (char *)buffer->pointer, (u32) required_size));
246 return_ACPI_STATUS(AE_OK);