ia64/kvm: compilation fix. export account_system_vtime.
[pv_ops_mirror.git] / drivers / acpi / namespace / nseval.c
blob14bdfa92bea04cc9da1bfde6a0344ad57a29e2f4
1 /*******************************************************************************
3 * Module Name: nseval - Object evaluation, includes control method execution
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
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.
44 #include <acpi/acpi.h>
45 #include <acpi/acparser.h>
46 #include <acpi/acinterp.h>
47 #include <acpi/acnamesp.h>
49 #define _COMPONENT ACPI_NAMESPACE
50 ACPI_MODULE_NAME("nseval")
52 /*******************************************************************************
54 * FUNCTION: acpi_ns_evaluate
56 * PARAMETERS: Info - Evaluation info block, contains:
57 * prefix_node - Prefix or Method/Object Node to execute
58 * Pathname - Name of method to execute, If NULL, the
59 * Node is the object to execute
60 * Parameters - List of parameters to pass to the method,
61 * terminated by NULL. Params itself may be
62 * NULL if no parameters are being passed.
63 * return_object - Where to put method's return value (if
64 * any). If NULL, no value is returned.
65 * parameter_type - Type of Parameter list
66 * return_object - Where to put method's return value (if
67 * any). If NULL, no value is returned.
68 * Flags - ACPI_IGNORE_RETURN_VALUE to delete return
70 * RETURN: Status
72 * DESCRIPTION: Execute a control method or return the current value of an
73 * ACPI namespace object.
75 * MUTEX: Locks interpreter
77 ******************************************************************************/
78 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
80 acpi_status status;
82 ACPI_FUNCTION_TRACE(ns_evaluate);
84 if (!info) {
85 return_ACPI_STATUS(AE_BAD_PARAMETER);
88 /* Initialize the return value to an invalid object */
90 info->return_object = NULL;
93 * Get the actual namespace node for the target object. Handles these cases:
95 * 1) Null node, Pathname (absolute path)
96 * 2) Node, Pathname (path relative to Node)
97 * 3) Node, Null Pathname
99 status = acpi_ns_get_node(info->prefix_node, info->pathname,
100 ACPI_NS_NO_UPSEARCH, &info->resolved_node);
101 if (ACPI_FAILURE(status)) {
102 return_ACPI_STATUS(status);
106 * For a method alias, we must grab the actual method node so that proper
107 * scoping context will be established before execution.
109 if (acpi_ns_get_type(info->resolved_node) ==
110 ACPI_TYPE_LOCAL_METHOD_ALIAS) {
111 info->resolved_node =
112 ACPI_CAST_PTR(struct acpi_namespace_node,
113 info->resolved_node->object);
116 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n", info->pathname,
117 info->resolved_node,
118 acpi_ns_get_attached_object(info->resolved_node)));
121 * Two major cases here:
123 * 1) The object is a control method -- execute it
124 * 2) The object is not a method -- just return it's current value
126 if (acpi_ns_get_type(info->resolved_node) == ACPI_TYPE_METHOD) {
128 * 1) Object is a control method - execute it
131 /* Verify that there is a method object associated with this node */
133 info->obj_desc =
134 acpi_ns_get_attached_object(info->resolved_node);
135 if (!info->obj_desc) {
136 ACPI_ERROR((AE_INFO,
137 "Control method has no attached sub-object"));
138 return_ACPI_STATUS(AE_NULL_OBJECT);
141 ACPI_DUMP_PATHNAME(info->resolved_node, "Execute Method:",
142 ACPI_LV_INFO, _COMPONENT);
144 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
145 "Method at AML address %p Length %X\n",
146 info->obj_desc->method.aml_start + 1,
147 info->obj_desc->method.aml_length - 1));
150 * Any namespace deletion must acquire both the namespace and
151 * interpreter locks to ensure that no thread is using the portion of
152 * the namespace that is being deleted.
154 * Execute the method via the interpreter. The interpreter is locked
155 * here before calling into the AML parser
157 acpi_ex_enter_interpreter();
158 status = acpi_ps_execute_method(info);
159 acpi_ex_exit_interpreter();
160 } else {
162 * 2) Object is not a method, return its current value
166 * Objects require additional resolution steps (e.g., the Node may be
167 * a field that must be read, etc.) -- we can't just grab the object
168 * out of the node.
170 * Use resolve_node_to_value() to get the associated value.
172 * NOTE: we can get away with passing in NULL for a walk state because
173 * resolved_node is guaranteed to not be a reference to either a method
174 * local or a method argument (because this interface is never called
175 * from a running method.)
177 * Even though we do not directly invoke the interpreter for object
178 * resolution, we must lock it because we could access an opregion.
179 * The opregion access code assumes that the interpreter is locked.
181 acpi_ex_enter_interpreter();
183 /* Function has a strange interface */
185 status =
186 acpi_ex_resolve_node_to_value(&info->resolved_node, NULL);
187 acpi_ex_exit_interpreter();
190 * If acpi_ex_resolve_node_to_value() succeeded, the return value was placed
191 * in resolved_node.
193 if (ACPI_SUCCESS(status)) {
194 status = AE_CTRL_RETURN_VALUE;
195 info->return_object =
196 ACPI_CAST_PTR(union acpi_operand_object,
197 info->resolved_node);
199 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
200 "Returning object %p [%s]\n",
201 info->return_object,
202 acpi_ut_get_object_type_name(info->
203 return_object)));
208 * Check if there is a return value that must be dealt with
210 if (status == AE_CTRL_RETURN_VALUE) {
212 /* If caller does not want the return value, delete it */
214 if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
215 acpi_ut_remove_reference(info->return_object);
216 info->return_object = NULL;
219 /* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */
221 status = AE_OK;
224 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
225 "*** Completed evaluation of object %s ***\n",
226 info->pathname));
229 * Namespace was unlocked by the handling acpi_ns* function, so we
230 * just return
232 return_ACPI_STATUS(status);