1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /*******************************************************************************
3 *
4 * Module Name: nseval - Object evaluation, includes control method execution
5 *
6 ******************************************************************************/
7
8 #include <acpi/acpi.h>
9 #include "accommon.h"
10 #include "acparser.h"
11 #include "acinterp.h"
12 #include "acnamesp.h"
13
14 #define _COMPONENT ACPI_NAMESPACE
15 ACPI_MODULE_NAME("nseval")
16
17 /*******************************************************************************
18 *
19 * FUNCTION: acpi_ns_evaluate
20 *
21 * PARAMETERS: info - Evaluation info block, contains these fields
22 * and more:
23 * prefix_node - Prefix or Method/Object Node to execute
24 * relative_path - Name of method to execute, If NULL, the
25 * Node is the object to execute
26 * parameters - List of parameters to pass to the method,
27 * terminated by NULL. Params itself may be
28 * NULL if no parameters are being passed.
29 * parameter_type - Type of Parameter list
30 * return_object - Where to put method's return value (if
31 * any). If NULL, no value is returned.
32 * flags - ACPI_IGNORE_RETURN_VALUE to delete return
33 *
34 * RETURN: Status
35 *
36 * DESCRIPTION: Execute a control method or return the current value of an
37 * ACPI namespace object.
38 *
39 * MUTEX: Locks interpreter
40 *
41 ******************************************************************************/
42 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
43 {
44 acpi_status status;
45
46 ACPI_FUNCTION_TRACE(ns_evaluate);
47
48 if (!info) {
49 return_ACPI_STATUS(AE_BAD_PARAMETER);
50 }
51
52 if (!info->node) {
53 /*
54 * Get the actual namespace node for the target object if we
55 * need to. Handles these cases:
56 *
57 * 1) Null node, valid pathname from root (absolute path)
58 * 2) Node and valid pathname (path relative to Node)
59 * 3) Node, Null pathname
60 */
61 status =
62 acpi_ns_get_node(info->prefix_node, info->relative_pathname,
63 ACPI_NS_NO_UPSEARCH, &info->node);
64 if (ACPI_FAILURE(status)) {
65 return_ACPI_STATUS(status);
66 }
67 }
68
69 /*
70 * For a method alias, we must grab the actual method node so that
71 * proper scoping context will be established before execution.
72 */
73 if (acpi_ns_get_type(info->node) == ACPI_TYPE_LOCAL_METHOD_ALIAS) {
74 info->node =
75 ACPI_CAST_PTR(struct acpi_namespace_node,
76 info->node->object);
77 }
78
79 /* Complete the info block initialization */
80
81 info->return_object = NULL;
82 info->node_flags = info->node->flags;
83 info->obj_desc = acpi_ns_get_attached_object(info->node);
84
85 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n",
86 info->relative_pathname, info->node,
87 acpi_ns_get_attached_object(info->node)));
88
89 /* Get info if we have a predefined name (_HID, etc.) */
90
91 info->predefined =
92 acpi_ut_match_predefined_method(info->node->name.ascii);
93
94 /* Get the full pathname to the object, for use in warning messages */
95
96 info->full_pathname = acpi_ns_get_normalized_pathname(info->node, TRUE);
97 if (!info->full_pathname) {
98 return_ACPI_STATUS(AE_NO_MEMORY);
99 }
100
101 /* Optional object evaluation log */
102
103 ACPI_DEBUG_PRINT_RAW((ACPI_DB_EVALUATION,
104 "%-26s: %s (%s)\n", " Enter evaluation",
105 &info->full_pathname[1],
106 acpi_ut_get_type_name(info->node->type)));
107
108 /* Count the number of arguments being passed in */
109
110 info->param_count = 0;
111 if (info->parameters) {
112 while (info->parameters[info->param_count]) {
113 info->param_count++;
114 }
115
116 /* Warn on impossible argument count */
117
118 if (info->param_count > ACPI_METHOD_NUM_ARGS) {
119 ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
120 ACPI_WARN_ALWAYS,
121 "Excess arguments (%u) - using only %u",
122 info->param_count,
123 ACPI_METHOD_NUM_ARGS));
124
125 info->param_count = ACPI_METHOD_NUM_ARGS;
126 }
127 }
128
129 /*
130 * For predefined names: Check that the declared argument count
131 * matches the ACPI spec -- otherwise this is a BIOS error.
132 */
133 acpi_ns_check_acpi_compliance(info->full_pathname, info->node,
134 info->predefined);
135
136 /*
137 * For all names: Check that the incoming argument count for
138 * this method/object matches the actual ASL/AML definition.
139 */
140 acpi_ns_check_argument_count(info->full_pathname, info->node,
141 info->param_count, info->predefined);
142
143 /* For predefined names: Typecheck all incoming arguments */
144
145 acpi_ns_check_argument_types(info);
146
147 /*
148 * Three major evaluation cases:
149 *
150 * 1) Object types that cannot be evaluated by definition
151 * 2) The object is a control method -- execute it
152 * 3) The object is not a method -- just return it's current value
153 */
154 switch (acpi_ns_get_type(info->node)) {
155 case ACPI_TYPE_ANY:
156 case ACPI_TYPE_DEVICE:
157 case ACPI_TYPE_EVENT:
158 case ACPI_TYPE_MUTEX:
159 case ACPI_TYPE_REGION:
160 case ACPI_TYPE_THERMAL:
161 case ACPI_TYPE_LOCAL_SCOPE:
162 /*
163 * 1) Disallow evaluation of these object types. For these,
164 * object evaluation is undefined.
165 */
166 ACPI_ERROR((AE_INFO,
167 "%s: This object type [%s] "
168 "never contains data and cannot be evaluated",
169 info->full_pathname,
170 acpi_ut_get_type_name(info->node->type)));
171
172 status = AE_TYPE;
173 goto cleanup;
174
175 case ACPI_TYPE_METHOD:
176 /*
177 * 2) Object is a control method - execute it
178 */
179
180 /* Verify that there is a method object associated with this node */
181
182 if (!info->obj_desc) {
183 ACPI_ERROR((AE_INFO,
184 "%s: Method has no attached sub-object",
185 info->full_pathname));
186 status = AE_NULL_OBJECT;
187 goto cleanup;
188 }
189
190 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
191 "**** Execute method [%s] at AML address %p length %X\n",
192 info->full_pathname,
193 info->obj_desc->method.aml_start + 1,
194 info->obj_desc->method.aml_length - 1));
195
196 /*
197 * Any namespace deletion must acquire both the namespace and
198 * interpreter locks to ensure that no thread is using the portion of
199 * the namespace that is being deleted.
200 *
201 * Execute the method via the interpreter. The interpreter is locked
202 * here before calling into the AML parser
203 */
204 acpi_ex_enter_interpreter();
205 status = acpi_ps_execute_method(info);
206 acpi_ex_exit_interpreter();
207 break;
208
209 default:
210 /*
211 * 3) All other non-method objects -- get the current object value
212 */
213
214 /*
215 * Some objects require additional resolution steps (e.g., the Node
216 * may be a field that must be read, etc.) -- we can't just grab
217 * the object out of the node.
218 *
219 * Use resolve_node_to_value() to get the associated value.
220 *
221 * NOTE: we can get away with passing in NULL for a walk state because
222 * the Node is guaranteed to not be a reference to either a method
223 * local or a method argument (because this interface is never called
224 * from a running method.)
225 *
226 * Even though we do not directly invoke the interpreter for object
227 * resolution, we must lock it because we could access an op_region.
228 * The op_region access code assumes that the interpreter is locked.
229 */
230 acpi_ex_enter_interpreter();
231
232 /* TBD: resolve_node_to_value has a strange interface, fix */
233
234 info->return_object =
235 ACPI_CAST_PTR(union acpi_operand_object, info->node);
236
237 status =
238 acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
239 (struct acpi_namespace_node,
240 &info->return_object), NULL);
241 acpi_ex_exit_interpreter();
242
243 if (ACPI_FAILURE(status)) {
244 info->return_object = NULL;
245 goto cleanup;
246 }
247
248 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Returned object %p [%s]\n",
249 info->return_object,
250 acpi_ut_get_object_type_name(info->
251 return_object)));
252
253 status = AE_CTRL_RETURN_VALUE; /* Always has a "return value" */
254 break;
255 }
256
257 /*
258 * For predefined names, check the return value against the ACPI
259 * specification. Some incorrect return value types are repaired.
260 */
261 (void)acpi_ns_check_return_value(info->node, info, info->param_count,
262 status, &info->return_object);
263
264 /* Check if there is a return value that must be dealt with */
265
266 if (status == AE_CTRL_RETURN_VALUE) {
267
268 /* If caller does not want the return value, delete it */
269
270 if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
271 acpi_ut_remove_reference(info->return_object);
272 info->return_object = NULL;
273 }
274
275 /* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */
276
277 status = AE_OK;
278 } else if (ACPI_FAILURE(status)) {
279
280 /* If return_object exists, delete it */
281
282 if (info->return_object) {
283 acpi_ut_remove_reference(info->return_object);
284 info->return_object = NULL;
285 }
286 }
287
288 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
289 "*** Completed evaluation of object %s ***\n",
290 info->relative_pathname));
291
292 cleanup:
293 /* Optional object evaluation log */
294
295 ACPI_DEBUG_PRINT_RAW((ACPI_DB_EVALUATION,
296 "%-26s: %s\n", " Exit evaluation",
297 &info->full_pathname[1]));
298
299 /*
300 * Namespace was unlocked by the handling acpi_ns* function, so we
301 * just free the pathname and return
302 */
303 ACPI_FREE(info->full_pathname);
304 info->full_pathname = NULL;
305 return_ACPI_STATUS(status);
306 }