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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/******************************************************************************
2 *
3 * Module Name: psparse - Parser top level AML parse routines
4 *
5 *****************************************************************************/
6
7/*
Len Brown75a44ce2008-04-23 23:00:13 -04008 * Copyright (C) 2000 - 2008, Intel Corp.
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * All rights reserved.
10 *
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.
25 *
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.
29 *
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.
42 */
43
Linus Torvalds1da177e2005-04-16 15:20:36 -070044/*
45 * Parse the AML and build an operation tree as most interpreters,
46 * like Perl, do. Parsing is done by hand rather than with a YACC
47 * generated parser to tightly constrain stack and dynamic memory
48 * usage. At the same time, parsing is kept flexible and the code
49 * fairly compact by parsing based on a list of AML opcode
50 * templates in aml_op_info[]
51 */
52
53#include <acpi/acpi.h>
Len Browne2f7a772009-01-09 00:30:03 -050054#include "accommon.h"
55#include "acparser.h"
56#include "acdispat.h"
57#include "amlcode.h"
58#include "acnamesp.h"
59#include "acinterp.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
61#define _COMPONENT ACPI_PARSER
Len Brown4be44fc2005-08-05 00:44:28 -040062ACPI_MODULE_NAME("psparse")
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
Linus Torvalds1da177e2005-04-16 15:20:36 -070064/*******************************************************************************
65 *
66 * FUNCTION: acpi_ps_get_opcode_size
67 *
68 * PARAMETERS: Opcode - An AML opcode
69 *
70 * RETURN: Size of the opcode, in bytes (1 or 2)
71 *
72 * DESCRIPTION: Get the size of the current opcode.
73 *
74 ******************************************************************************/
Len Brown4be44fc2005-08-05 00:44:28 -040075u32 acpi_ps_get_opcode_size(u32 opcode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070076{
77
78 /* Extended (2-byte) opcode if > 255 */
79
80 if (opcode > 0x00FF) {
81 return (2);
82 }
83
84 /* Otherwise, just a single byte opcode */
85
86 return (1);
87}
88
Linus Torvalds1da177e2005-04-16 15:20:36 -070089/*******************************************************************************
90 *
91 * FUNCTION: acpi_ps_peek_opcode
92 *
93 * PARAMETERS: parser_state - A parser state object
94 *
Robert Moore44f6c012005-04-18 22:49:35 -040095 * RETURN: Next AML opcode
Linus Torvalds1da177e2005-04-16 15:20:36 -070096 *
97 * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
98 *
99 ******************************************************************************/
100
Len Brown4be44fc2005-08-05 00:44:28 -0400101u16 acpi_ps_peek_opcode(struct acpi_parse_state * parser_state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102{
Len Brown4be44fc2005-08-05 00:44:28 -0400103 u8 *aml;
104 u16 opcode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105
106 aml = parser_state->aml;
Len Brown4be44fc2005-08-05 00:44:28 -0400107 opcode = (u16) ACPI_GET8(aml);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108
Robert Moore73459f72005-06-24 00:00:00 -0400109 if (opcode == AML_EXTENDED_OP_PREFIX) {
Bob Moore52fc0b02006-10-02 00:00:00 -0400110
Robert Moore73459f72005-06-24 00:00:00 -0400111 /* Extended opcode, get the second opcode byte */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112
113 aml++;
Len Brown4be44fc2005-08-05 00:44:28 -0400114 opcode = (u16) ((opcode << 8) | ACPI_GET8(aml));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 }
116
117 return (opcode);
118}
119
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120/*******************************************************************************
121 *
122 * FUNCTION: acpi_ps_complete_this_op
123 *
124 * PARAMETERS: walk_state - Current State
125 * Op - Op to complete
126 *
Robert Moore88ac00f2005-05-26 00:00:00 -0400127 * RETURN: Status
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 *
129 * DESCRIPTION: Perform any cleanup at the completion of an Op.
130 *
131 ******************************************************************************/
132
Robert Moore73459f72005-06-24 00:00:00 -0400133acpi_status
Len Brown4be44fc2005-08-05 00:44:28 -0400134acpi_ps_complete_this_op(struct acpi_walk_state * walk_state,
135 union acpi_parse_object * op)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136{
Len Brown4be44fc2005-08-05 00:44:28 -0400137 union acpi_parse_object *prev;
138 union acpi_parse_object *next;
139 const struct acpi_opcode_info *parent_info;
140 union acpi_parse_object *replacement_op = NULL;
Lin Mingc35def22008-09-27 11:28:46 +0800141 acpi_status status = AE_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
Bob Mooreb229cf92006-04-21 17:15:00 -0400143 ACPI_FUNCTION_TRACE_PTR(ps_complete_this_op, op);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144
145 /* Check for null Op, can happen if AML code is corrupt */
146
147 if (!op) {
Len Brown4be44fc2005-08-05 00:44:28 -0400148 return_ACPI_STATUS(AE_OK); /* OK for now */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 }
150
151 /* Delete this op and the subtree below it if asked to */
152
Len Brown4be44fc2005-08-05 00:44:28 -0400153 if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) !=
154 ACPI_PARSE_DELETE_TREE)
155 || (walk_state->op_info->class == AML_CLASS_ARGUMENT)) {
156 return_ACPI_STATUS(AE_OK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 }
158
159 /* Make sure that we only delete this subtree */
160
161 if (op->common.parent) {
Robert Moore88ac00f2005-05-26 00:00:00 -0400162 prev = op->common.parent->common.value.arg;
163 if (!prev) {
Bob Moore52fc0b02006-10-02 00:00:00 -0400164
Robert Moore88ac00f2005-05-26 00:00:00 -0400165 /* Nothing more to do */
166
167 goto cleanup;
168 }
169
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 /*
171 * Check if we need to replace the operator and its subtree
172 * with a return value op (placeholder op)
173 */
Len Brown4be44fc2005-08-05 00:44:28 -0400174 parent_info =
175 acpi_ps_get_opcode_info(op->common.parent->common.
176 aml_opcode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177
178 switch (parent_info->class) {
179 case AML_CLASS_CONTROL:
180 break;
181
182 case AML_CLASS_CREATE:
183
184 /*
185 * These opcodes contain term_arg operands. The current
186 * op must be replaced by a placeholder return op
187 */
Len Brown4be44fc2005-08-05 00:44:28 -0400188 replacement_op =
189 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 if (!replacement_op) {
Lin Mingc35def22008-09-27 11:28:46 +0800191 status = AE_NO_MEMORY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 }
193 break;
194
195 case AML_CLASS_NAMED_OBJECT:
196
197 /*
198 * These opcodes contain term_arg operands. The current
199 * op must be replaced by a placeholder return op
200 */
Len Brown4be44fc2005-08-05 00:44:28 -0400201 if ((op->common.parent->common.aml_opcode ==
202 AML_REGION_OP)
203 || (op->common.parent->common.aml_opcode ==
204 AML_DATA_REGION_OP)
205 || (op->common.parent->common.aml_opcode ==
206 AML_BUFFER_OP)
207 || (op->common.parent->common.aml_opcode ==
208 AML_PACKAGE_OP)
209 || (op->common.parent->common.aml_opcode ==
Lin Mingef805d92008-04-10 19:06:41 +0400210 AML_BANK_FIELD_OP)
211 || (op->common.parent->common.aml_opcode ==
Len Brown4be44fc2005-08-05 00:44:28 -0400212 AML_VAR_PACKAGE_OP)) {
213 replacement_op =
214 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 if (!replacement_op) {
Lin Mingc35def22008-09-27 11:28:46 +0800216 status = AE_NO_MEMORY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 }
Len Brown4be44fc2005-08-05 00:44:28 -0400218 } else
219 if ((op->common.parent->common.aml_opcode ==
220 AML_NAME_OP)
221 && (walk_state->pass_number <=
222 ACPI_IMODE_LOAD_PASS2)) {
223 if ((op->common.aml_opcode == AML_BUFFER_OP)
224 || (op->common.aml_opcode == AML_PACKAGE_OP)
225 || (op->common.aml_opcode ==
226 AML_VAR_PACKAGE_OP)) {
227 replacement_op =
228 acpi_ps_alloc_op(op->common.
229 aml_opcode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 if (!replacement_op) {
Lin Mingc35def22008-09-27 11:28:46 +0800231 status = AE_NO_MEMORY;
232 } else {
233 replacement_op->named.data =
234 op->named.data;
235 replacement_op->named.length =
236 op->named.length;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 }
239 }
240 break;
241
242 default:
Robert Moore88ac00f2005-05-26 00:00:00 -0400243
Len Brown4be44fc2005-08-05 00:44:28 -0400244 replacement_op =
245 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246 if (!replacement_op) {
Lin Mingc35def22008-09-27 11:28:46 +0800247 status = AE_NO_MEMORY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 }
249 }
250
251 /* We must unlink this op from the parent tree */
252
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 if (prev == op) {
Bob Moore52fc0b02006-10-02 00:00:00 -0400254
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 /* This op is the first in the list */
256
257 if (replacement_op) {
Len Brown4be44fc2005-08-05 00:44:28 -0400258 replacement_op->common.parent =
259 op->common.parent;
260 replacement_op->common.value.arg = NULL;
261 replacement_op->common.node = op->common.node;
262 op->common.parent->common.value.arg =
263 replacement_op;
264 replacement_op->common.next = op->common.next;
265 } else {
266 op->common.parent->common.value.arg =
267 op->common.next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 }
269 }
270
271 /* Search the parent list */
272
Len Brown4be44fc2005-08-05 00:44:28 -0400273 else
274 while (prev) {
Bob Moore52fc0b02006-10-02 00:00:00 -0400275
Len Brown4be44fc2005-08-05 00:44:28 -0400276 /* Traverse all siblings in the parent's argument list */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277
Len Brown4be44fc2005-08-05 00:44:28 -0400278 next = prev->common.next;
279 if (next == op) {
280 if (replacement_op) {
281 replacement_op->common.parent =
282 op->common.parent;
283 replacement_op->common.value.
284 arg = NULL;
285 replacement_op->common.node =
286 op->common.node;
287 prev->common.next =
288 replacement_op;
289 replacement_op->common.next =
290 op->common.next;
291 next = NULL;
292 } else {
293 prev->common.next =
294 op->common.next;
295 next = NULL;
296 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297 }
Len Brown4be44fc2005-08-05 00:44:28 -0400298 prev = next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300 }
301
Len Brown4be44fc2005-08-05 00:44:28 -0400302 cleanup:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303
Robert Moore44f6c012005-04-18 22:49:35 -0400304 /* Now we can actually delete the subtree rooted at Op */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305
Len Brown4be44fc2005-08-05 00:44:28 -0400306 acpi_ps_delete_parse_tree(op);
Lin Mingc35def22008-09-27 11:28:46 +0800307 return_ACPI_STATUS(status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308}
309
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310/*******************************************************************************
311 *
312 * FUNCTION: acpi_ps_next_parse_state
313 *
Robert Moore44f6c012005-04-18 22:49:35 -0400314 * PARAMETERS: walk_state - Current state
315 * Op - Current parse op
316 * callback_status - Status from previous operation
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 *
318 * RETURN: Status
319 *
320 * DESCRIPTION: Update the parser state based upon the return exception from
321 * the parser callback.
322 *
323 ******************************************************************************/
324
Robert Moore73459f72005-06-24 00:00:00 -0400325acpi_status
Len Brown4be44fc2005-08-05 00:44:28 -0400326acpi_ps_next_parse_state(struct acpi_walk_state *walk_state,
327 union acpi_parse_object *op,
328 acpi_status callback_status)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329{
Len Brown4be44fc2005-08-05 00:44:28 -0400330 struct acpi_parse_state *parser_state = &walk_state->parser_state;
331 acpi_status status = AE_CTRL_PENDING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332
Bob Mooreb229cf92006-04-21 17:15:00 -0400333 ACPI_FUNCTION_TRACE_PTR(ps_next_parse_state, op);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334
335 switch (callback_status) {
336 case AE_CTRL_TERMINATE:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 /*
338 * A control method was terminated via a RETURN statement.
339 * The walk of this method is complete.
340 */
341 parser_state->aml = parser_state->aml_end;
342 status = AE_CTRL_TERMINATE;
343 break;
344
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 case AE_CTRL_BREAK:
346
347 parser_state->aml = walk_state->aml_last_while;
348 walk_state->control_state->common.value = FALSE;
Bob Moore773069d2008-04-10 19:06:36 +0400349 status = AE_CTRL_BREAK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 break;
351
352 case AE_CTRL_CONTINUE:
353
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 parser_state->aml = walk_state->aml_last_while;
Bob Moore773069d2008-04-10 19:06:36 +0400355 status = AE_CTRL_CONTINUE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 break;
357
358 case AE_CTRL_PENDING:
359
360 parser_state->aml = walk_state->aml_last_while;
361 break;
362
363#if 0
364 case AE_CTRL_SKIP:
365
366 parser_state->aml = parser_state->scope->parse_scope.pkg_end;
367 status = AE_OK;
368 break;
369#endif
370
371 case AE_CTRL_TRUE:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 /*
373 * Predicate of an IF was true, and we are at the matching ELSE.
374 * Just close out this package
375 */
Len Brown4be44fc2005-08-05 00:44:28 -0400376 parser_state->aml = acpi_ps_get_next_package_end(parser_state);
Bob Moore773069d2008-04-10 19:06:36 +0400377 status = AE_CTRL_PENDING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 break;
379
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 case AE_CTRL_FALSE:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 /*
382 * Either an IF/WHILE Predicate was false or we encountered a BREAK
383 * opcode. In both cases, we do not execute the rest of the
384 * package; We simply close out the parent (finishing the walk of
385 * this branch of the tree) and continue execution at the parent
386 * level.
387 */
388 parser_state->aml = parser_state->scope->parse_scope.pkg_end;
389
390 /* In the case of a BREAK, just force a predicate (if any) to FALSE */
391
392 walk_state->control_state->common.value = FALSE;
393 status = AE_CTRL_END;
394 break;
395
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 case AE_CTRL_TRANSFER:
397
Robert Moore44f6c012005-04-18 22:49:35 -0400398 /* A method call (invocation) -- transfer control */
399
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 status = AE_CTRL_TRANSFER;
401 walk_state->prev_op = op;
402 walk_state->method_call_op = op;
Len Brown4be44fc2005-08-05 00:44:28 -0400403 walk_state->method_call_node =
404 (op->common.value.arg)->common.node;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405
406 /* Will return value (if any) be used by the caller? */
407
Len Brown4be44fc2005-08-05 00:44:28 -0400408 walk_state->return_used =
409 acpi_ds_is_result_used(op, walk_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 break;
411
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 default:
Robert Moore44f6c012005-04-18 22:49:35 -0400413
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 status = callback_status;
415 if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) {
416 status = AE_OK;
417 }
418 break;
419 }
420
Len Brown4be44fc2005-08-05 00:44:28 -0400421 return_ACPI_STATUS(status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422}
423
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424/*******************************************************************************
425 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 * FUNCTION: acpi_ps_parse_aml
427 *
Robert Moore44f6c012005-04-18 22:49:35 -0400428 * PARAMETERS: walk_state - Current state
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 *
430 *
431 * RETURN: Status
432 *
433 * DESCRIPTION: Parse raw AML and return a tree of ops
434 *
435 ******************************************************************************/
436
Len Brown4be44fc2005-08-05 00:44:28 -0400437acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438{
Len Brown4be44fc2005-08-05 00:44:28 -0400439 acpi_status status;
Len Brown4be44fc2005-08-05 00:44:28 -0400440 struct acpi_thread_state *thread;
441 struct acpi_thread_state *prev_walk_list = acpi_gbl_current_walk_list;
442 struct acpi_walk_state *previous_walk_state;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443
Bob Mooreb229cf92006-04-21 17:15:00 -0400444 ACPI_FUNCTION_TRACE(ps_parse_aml);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445
Len Brown4be44fc2005-08-05 00:44:28 -0400446 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
Bob Mooreb229cf92006-04-21 17:15:00 -0400447 "Entered with WalkState=%p Aml=%p size=%X\n",
Len Brown4be44fc2005-08-05 00:44:28 -0400448 walk_state, walk_state->parser_state.aml,
449 walk_state->parser_state.aml_size));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450
Bob Moorea8fadc92008-11-13 09:45:35 +0800451 if (!walk_state->parser_state.aml) {
452 return_ACPI_STATUS(AE_NULL_OBJECT);
453 }
454
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 /* Create and initialize a new thread state */
456
Len Brown4be44fc2005-08-05 00:44:28 -0400457 thread = acpi_ut_create_thread_state();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 if (!thread) {
Lin Ming84d4db72008-11-12 14:56:59 +0800459 if (walk_state->method_desc) {
460
461 /* Executing a control method - additional cleanup */
462
463 acpi_ds_terminate_control_method(
464 walk_state->method_desc, walk_state);
465 }
466
Bob Moore41195322006-05-26 16:36:00 -0400467 acpi_ds_delete_walk_state(walk_state);
Len Brown4be44fc2005-08-05 00:44:28 -0400468 return_ACPI_STATUS(AE_NO_MEMORY);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 }
470
471 walk_state->thread = thread;
Bob Moore967440e32006-06-23 17:04:00 -0400472
473 /*
474 * If executing a method, the starting sync_level is this method's
475 * sync_level
476 */
477 if (walk_state->method_desc) {
478 walk_state->thread->current_sync_level =
479 walk_state->method_desc->method.sync_level;
480 }
481
Len Brown4be44fc2005-08-05 00:44:28 -0400482 acpi_ds_push_walk_state(walk_state, thread);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483
484 /*
485 * This global allows the AML debugger to get a handle to the currently
486 * executing control method.
487 */
488 acpi_gbl_current_walk_list = thread;
489
490 /*
491 * Execute the walk loop as long as there is a valid Walk State. This
492 * handles nested control method invocations without recursion.
493 */
Len Brown4be44fc2005-08-05 00:44:28 -0400494 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495
496 status = AE_OK;
497 while (walk_state) {
Len Brown4be44fc2005-08-05 00:44:28 -0400498 if (ACPI_SUCCESS(status)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 /*
500 * The parse_loop executes AML until the method terminates
501 * or calls another method.
502 */
Len Brown4be44fc2005-08-05 00:44:28 -0400503 status = acpi_ps_parse_loop(walk_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 }
505
Len Brown4be44fc2005-08-05 00:44:28 -0400506 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
507 "Completed one call to walk loop, %s State=%p\n",
508 acpi_format_exception(status), walk_state));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509
510 if (status == AE_CTRL_TRANSFER) {
511 /*
512 * A method call was detected.
513 * Transfer control to the called control method
514 */
Len Brown4be44fc2005-08-05 00:44:28 -0400515 status =
516 acpi_ds_call_control_method(thread, walk_state,
517 NULL);
Bob Moore967440e32006-06-23 17:04:00 -0400518 if (ACPI_FAILURE(status)) {
519 status =
520 acpi_ds_method_error(status, walk_state);
521 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522
523 /*
524 * If the transfer to the new method method call worked, a new walk
525 * state was created -- get it
526 */
Len Brown4be44fc2005-08-05 00:44:28 -0400527 walk_state = acpi_ds_get_current_walk_state(thread);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528 continue;
Len Brown4be44fc2005-08-05 00:44:28 -0400529 } else if (status == AE_CTRL_TERMINATE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 status = AE_OK;
Len Brown4be44fc2005-08-05 00:44:28 -0400531 } else if ((status != AE_OK) && (walk_state->method_desc)) {
Bob Moore52fc0b02006-10-02 00:00:00 -0400532
Bob Moorec51a4de2005-11-17 13:07:00 -0500533 /* Either the method parse or actual execution failed */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534
Bob Mooreb8e4d892006-01-27 16:43:00 -0500535 ACPI_ERROR_METHOD("Method parse/execution failed",
536 walk_state->method_node, NULL,
537 status);
Robert Mooreaff8c272005-09-02 17:24:17 -0400538
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 /* Check for possible multi-thread reentrancy problem */
540
541 if ((status == AE_ALREADY_EXISTS) &&
Bob Moore967440e32006-06-23 17:04:00 -0400542 (!walk_state->method_desc->method.mutex)) {
Bob Moore13b572a2007-02-02 19:48:20 +0300543 ACPI_INFO((AE_INFO,
Bob Moore6deb65d2008-04-10 19:06:38 +0400544 "Marking method %4.4s as Serialized because of AE_ALREADY_EXISTS error",
Bob Moore13b572a2007-02-02 19:48:20 +0300545 walk_state->method_node->name.
546 ascii));
547
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 /*
Bob Moorec51a4de2005-11-17 13:07:00 -0500549 * Method tried to create an object twice. The probable cause is
550 * that the method cannot handle reentrancy.
551 *
552 * The method is marked not_serialized, but it tried to create
Robert Moore44f6c012005-04-18 22:49:35 -0400553 * a named object, causing the second thread entrance to fail.
Bob Moorec51a4de2005-11-17 13:07:00 -0500554 * Workaround this problem by marking the method permanently
Robert Moore44f6c012005-04-18 22:49:35 -0400555 * as Serialized.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 */
Len Brown4be44fc2005-08-05 00:44:28 -0400557 walk_state->method_desc->method.method_flags |=
558 AML_METHOD_SERIALIZED;
Bob Moore967440e32006-06-23 17:04:00 -0400559 walk_state->method_desc->method.sync_level = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 }
561 }
562
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563 /* We are done with this walk, move on to the parent if any */
564
Len Brown4be44fc2005-08-05 00:44:28 -0400565 walk_state = acpi_ds_pop_walk_state(thread);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566
567 /* Reset the current scope to the beginning of scope stack */
568
Len Brown4be44fc2005-08-05 00:44:28 -0400569 acpi_ds_scope_stack_clear(walk_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570
571 /*
Bob Moorec51a4de2005-11-17 13:07:00 -0500572 * If we just returned from the execution of a control method or if we
573 * encountered an error during the method parse phase, there's lots of
574 * cleanup to do
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 */
Bob Moorec51a4de2005-11-17 13:07:00 -0500576 if (((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==
577 ACPI_PARSE_EXECUTE) || (ACPI_FAILURE(status))) {
Bob Mooreb229cf92006-04-21 17:15:00 -0400578 acpi_ds_terminate_control_method(walk_state->
579 method_desc,
580 walk_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 }
582
583 /* Delete this walk state and all linked control states */
584
Len Brown4be44fc2005-08-05 00:44:28 -0400585 acpi_ps_cleanup_scope(&walk_state->parser_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 previous_walk_state = walk_state;
587
Len Brown4be44fc2005-08-05 00:44:28 -0400588 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
Bob Mooreb229cf92006-04-21 17:15:00 -0400589 "ReturnValue=%p, ImplicitValue=%p State=%p\n",
Len Brown4be44fc2005-08-05 00:44:28 -0400590 walk_state->return_desc,
591 walk_state->implicit_return_obj, walk_state));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592
593 /* Check if we have restarted a preempted walk */
594
Len Brown4be44fc2005-08-05 00:44:28 -0400595 walk_state = acpi_ds_get_current_walk_state(thread);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 if (walk_state) {
Len Brown4be44fc2005-08-05 00:44:28 -0400597 if (ACPI_SUCCESS(status)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 /*
599 * There is another walk state, restart it.
600 * If the method return value is not used by the parent,
601 * The object is deleted
602 */
603 if (!previous_walk_state->return_desc) {
Lin Ming9accd4642008-04-10 19:06:42 +0400604 /*
605 * In slack mode execution, if there is no return value
606 * we should implicitly return zero (0) as a default value.
607 */
608 if (acpi_gbl_enable_interpreter_slack &&
609 !previous_walk_state->
610 implicit_return_obj) {
611 previous_walk_state->
612 implicit_return_obj =
613 acpi_ut_create_internal_object
614 (ACPI_TYPE_INTEGER);
615 if (!previous_walk_state->
616 implicit_return_obj) {
617 return_ACPI_STATUS
618 (AE_NO_MEMORY);
619 }
620
621 previous_walk_state->
622 implicit_return_obj->
623 integer.value = 0;
624 }
625
626 /* Restart the calling control method */
627
Len Brown4be44fc2005-08-05 00:44:28 -0400628 status =
629 acpi_ds_restart_control_method
630 (walk_state,
631 previous_walk_state->
632 implicit_return_obj);
633 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 /*
635 * We have a valid return value, delete any implicit
636 * return value.
637 */
Len Brown4be44fc2005-08-05 00:44:28 -0400638 acpi_ds_clear_implicit_return
639 (previous_walk_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640
Len Brown4be44fc2005-08-05 00:44:28 -0400641 status =
642 acpi_ds_restart_control_method
643 (walk_state,
644 previous_walk_state->return_desc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645 }
Len Brown4be44fc2005-08-05 00:44:28 -0400646 if (ACPI_SUCCESS(status)) {
647 walk_state->walk_type |=
648 ACPI_WALK_METHOD_RESTART;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649 }
Len Brown4be44fc2005-08-05 00:44:28 -0400650 } else {
Lin Mingd8a0ec92008-09-27 11:50:24 +0800651 /* On error, delete any return object or implicit return */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652
Len Brown4be44fc2005-08-05 00:44:28 -0400653 acpi_ut_remove_reference(previous_walk_state->
654 return_desc);
Lin Mingd8a0ec92008-09-27 11:50:24 +0800655 acpi_ds_clear_implicit_return
656 (previous_walk_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 }
658 }
659
660 /*
661 * Just completed a 1st-level method, save the final internal return
662 * value (if any)
663 */
664 else if (previous_walk_state->caller_return_desc) {
665 if (previous_walk_state->implicit_return_obj) {
Robert Moore44f6c012005-04-18 22:49:35 -0400666 *(previous_walk_state->caller_return_desc) =
Len Brown4be44fc2005-08-05 00:44:28 -0400667 previous_walk_state->implicit_return_obj;
668 } else {
669 /* NULL if no return value */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670
Robert Moore44f6c012005-04-18 22:49:35 -0400671 *(previous_walk_state->caller_return_desc) =
Len Brown4be44fc2005-08-05 00:44:28 -0400672 previous_walk_state->return_desc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673 }
Len Brown4be44fc2005-08-05 00:44:28 -0400674 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675 if (previous_walk_state->return_desc) {
Bob Moore52fc0b02006-10-02 00:00:00 -0400676
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 /* Caller doesn't want it, must delete it */
678
Len Brown4be44fc2005-08-05 00:44:28 -0400679 acpi_ut_remove_reference(previous_walk_state->
680 return_desc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681 }
682 if (previous_walk_state->implicit_return_obj) {
Bob Moore52fc0b02006-10-02 00:00:00 -0400683
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 /* Caller doesn't want it, must delete it */
685
Len Brown4be44fc2005-08-05 00:44:28 -0400686 acpi_ut_remove_reference(previous_walk_state->
687 implicit_return_obj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 }
689 }
690
Len Brown4be44fc2005-08-05 00:44:28 -0400691 acpi_ds_delete_walk_state(previous_walk_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692 }
693
694 /* Normal exit */
695
Len Brown4be44fc2005-08-05 00:44:28 -0400696 acpi_ex_release_all_mutexes(thread);
697 acpi_ut_delete_generic_state(ACPI_CAST_PTR
698 (union acpi_generic_state, thread));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 acpi_gbl_current_walk_list = prev_walk_list;
Len Brown4be44fc2005-08-05 00:44:28 -0400700 return_ACPI_STATUS(status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701}