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
15ACPI_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 ******************************************************************************/
42acpi_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
292cleanup:
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}
307