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1da177e4 LT |
1 | /****************************************************************************** |
2 | * | |
3 | * Module Name: psparse - Parser top level AML parse routines | |
4 | * | |
5 | *****************************************************************************/ | |
6 | ||
7 | /* | |
4a90c7e8 | 8 | * Copyright (C) 2000 - 2006, R. Byron Moore |
1da177e4 LT |
9 | * 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 | ||
1da177e4 LT |
44 | /* |
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> | |
54 | #include <acpi/acparser.h> | |
55 | #include <acpi/acdispat.h> | |
56 | #include <acpi/amlcode.h> | |
57 | #include <acpi/acnamesp.h> | |
58 | #include <acpi/acinterp.h> | |
59 | ||
60 | #define _COMPONENT ACPI_PARSER | |
4be44fcd | 61 | ACPI_MODULE_NAME("psparse") |
1da177e4 | 62 | |
1da177e4 LT |
63 | /******************************************************************************* |
64 | * | |
65 | * FUNCTION: acpi_ps_get_opcode_size | |
66 | * | |
67 | * PARAMETERS: Opcode - An AML opcode | |
68 | * | |
69 | * RETURN: Size of the opcode, in bytes (1 or 2) | |
70 | * | |
71 | * DESCRIPTION: Get the size of the current opcode. | |
72 | * | |
73 | ******************************************************************************/ | |
4be44fcd | 74 | u32 acpi_ps_get_opcode_size(u32 opcode) |
1da177e4 LT |
75 | { |
76 | ||
77 | /* Extended (2-byte) opcode if > 255 */ | |
78 | ||
79 | if (opcode > 0x00FF) { | |
80 | return (2); | |
81 | } | |
82 | ||
83 | /* Otherwise, just a single byte opcode */ | |
84 | ||
85 | return (1); | |
86 | } | |
87 | ||
1da177e4 LT |
88 | /******************************************************************************* |
89 | * | |
90 | * FUNCTION: acpi_ps_peek_opcode | |
91 | * | |
92 | * PARAMETERS: parser_state - A parser state object | |
93 | * | |
44f6c012 | 94 | * RETURN: Next AML opcode |
1da177e4 LT |
95 | * |
96 | * DESCRIPTION: Get next AML opcode (without incrementing AML pointer) | |
97 | * | |
98 | ******************************************************************************/ | |
99 | ||
4be44fcd | 100 | u16 acpi_ps_peek_opcode(struct acpi_parse_state * parser_state) |
1da177e4 | 101 | { |
4be44fcd LB |
102 | u8 *aml; |
103 | u16 opcode; | |
1da177e4 LT |
104 | |
105 | aml = parser_state->aml; | |
4be44fcd | 106 | opcode = (u16) ACPI_GET8(aml); |
1da177e4 | 107 | |
73459f73 RM |
108 | if (opcode == AML_EXTENDED_OP_PREFIX) { |
109 | /* Extended opcode, get the second opcode byte */ | |
1da177e4 LT |
110 | |
111 | aml++; | |
4be44fcd | 112 | opcode = (u16) ((opcode << 8) | ACPI_GET8(aml)); |
1da177e4 LT |
113 | } |
114 | ||
115 | return (opcode); | |
116 | } | |
117 | ||
1da177e4 LT |
118 | /******************************************************************************* |
119 | * | |
120 | * FUNCTION: acpi_ps_complete_this_op | |
121 | * | |
122 | * PARAMETERS: walk_state - Current State | |
123 | * Op - Op to complete | |
124 | * | |
88ac00f5 | 125 | * RETURN: Status |
1da177e4 LT |
126 | * |
127 | * DESCRIPTION: Perform any cleanup at the completion of an Op. | |
128 | * | |
129 | ******************************************************************************/ | |
130 | ||
73459f73 | 131 | acpi_status |
4be44fcd LB |
132 | acpi_ps_complete_this_op(struct acpi_walk_state * walk_state, |
133 | union acpi_parse_object * op) | |
1da177e4 | 134 | { |
4be44fcd LB |
135 | union acpi_parse_object *prev; |
136 | union acpi_parse_object *next; | |
137 | const struct acpi_opcode_info *parent_info; | |
138 | union acpi_parse_object *replacement_op = NULL; | |
1da177e4 | 139 | |
4be44fcd | 140 | ACPI_FUNCTION_TRACE_PTR("ps_complete_this_op", op); |
1da177e4 LT |
141 | |
142 | /* Check for null Op, can happen if AML code is corrupt */ | |
143 | ||
144 | if (!op) { | |
4be44fcd | 145 | return_ACPI_STATUS(AE_OK); /* OK for now */ |
1da177e4 LT |
146 | } |
147 | ||
148 | /* Delete this op and the subtree below it if asked to */ | |
149 | ||
4be44fcd LB |
150 | if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) != |
151 | ACPI_PARSE_DELETE_TREE) | |
152 | || (walk_state->op_info->class == AML_CLASS_ARGUMENT)) { | |
153 | return_ACPI_STATUS(AE_OK); | |
1da177e4 LT |
154 | } |
155 | ||
156 | /* Make sure that we only delete this subtree */ | |
157 | ||
158 | if (op->common.parent) { | |
88ac00f5 RM |
159 | prev = op->common.parent->common.value.arg; |
160 | if (!prev) { | |
161 | /* Nothing more to do */ | |
162 | ||
163 | goto cleanup; | |
164 | } | |
165 | ||
1da177e4 LT |
166 | /* |
167 | * Check if we need to replace the operator and its subtree | |
168 | * with a return value op (placeholder op) | |
169 | */ | |
4be44fcd LB |
170 | parent_info = |
171 | acpi_ps_get_opcode_info(op->common.parent->common. | |
172 | aml_opcode); | |
1da177e4 LT |
173 | |
174 | switch (parent_info->class) { | |
175 | case AML_CLASS_CONTROL: | |
176 | break; | |
177 | ||
178 | case AML_CLASS_CREATE: | |
179 | ||
180 | /* | |
181 | * These opcodes contain term_arg operands. The current | |
182 | * op must be replaced by a placeholder return op | |
183 | */ | |
4be44fcd LB |
184 | replacement_op = |
185 | acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); | |
1da177e4 | 186 | if (!replacement_op) { |
88ac00f5 | 187 | goto allocate_error; |
1da177e4 LT |
188 | } |
189 | break; | |
190 | ||
191 | case AML_CLASS_NAMED_OBJECT: | |
192 | ||
193 | /* | |
194 | * These opcodes contain term_arg operands. The current | |
195 | * op must be replaced by a placeholder return op | |
196 | */ | |
4be44fcd LB |
197 | if ((op->common.parent->common.aml_opcode == |
198 | AML_REGION_OP) | |
199 | || (op->common.parent->common.aml_opcode == | |
200 | AML_DATA_REGION_OP) | |
201 | || (op->common.parent->common.aml_opcode == | |
202 | AML_BUFFER_OP) | |
203 | || (op->common.parent->common.aml_opcode == | |
204 | AML_PACKAGE_OP) | |
205 | || (op->common.parent->common.aml_opcode == | |
206 | AML_VAR_PACKAGE_OP)) { | |
207 | replacement_op = | |
208 | acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); | |
1da177e4 | 209 | if (!replacement_op) { |
88ac00f5 | 210 | goto allocate_error; |
1da177e4 | 211 | } |
4be44fcd LB |
212 | } else |
213 | if ((op->common.parent->common.aml_opcode == | |
214 | AML_NAME_OP) | |
215 | && (walk_state->pass_number <= | |
216 | ACPI_IMODE_LOAD_PASS2)) { | |
217 | if ((op->common.aml_opcode == AML_BUFFER_OP) | |
218 | || (op->common.aml_opcode == AML_PACKAGE_OP) | |
219 | || (op->common.aml_opcode == | |
220 | AML_VAR_PACKAGE_OP)) { | |
221 | replacement_op = | |
222 | acpi_ps_alloc_op(op->common. | |
223 | aml_opcode); | |
1da177e4 | 224 | if (!replacement_op) { |
88ac00f5 | 225 | goto allocate_error; |
1da177e4 LT |
226 | } |
227 | ||
4be44fcd LB |
228 | replacement_op->named.data = |
229 | op->named.data; | |
230 | replacement_op->named.length = | |
231 | op->named.length; | |
1da177e4 LT |
232 | } |
233 | } | |
234 | break; | |
235 | ||
236 | default: | |
88ac00f5 | 237 | |
4be44fcd LB |
238 | replacement_op = |
239 | acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); | |
1da177e4 | 240 | if (!replacement_op) { |
88ac00f5 | 241 | goto allocate_error; |
1da177e4 LT |
242 | } |
243 | } | |
244 | ||
245 | /* We must unlink this op from the parent tree */ | |
246 | ||
1da177e4 LT |
247 | if (prev == op) { |
248 | /* This op is the first in the list */ | |
249 | ||
250 | if (replacement_op) { | |
4be44fcd LB |
251 | replacement_op->common.parent = |
252 | op->common.parent; | |
253 | replacement_op->common.value.arg = NULL; | |
254 | replacement_op->common.node = op->common.node; | |
255 | op->common.parent->common.value.arg = | |
256 | replacement_op; | |
257 | replacement_op->common.next = op->common.next; | |
258 | } else { | |
259 | op->common.parent->common.value.arg = | |
260 | op->common.next; | |
1da177e4 LT |
261 | } |
262 | } | |
263 | ||
264 | /* Search the parent list */ | |
265 | ||
4be44fcd LB |
266 | else |
267 | while (prev) { | |
268 | /* Traverse all siblings in the parent's argument list */ | |
269 | ||
270 | next = prev->common.next; | |
271 | if (next == op) { | |
272 | if (replacement_op) { | |
273 | replacement_op->common.parent = | |
274 | op->common.parent; | |
275 | replacement_op->common.value. | |
276 | arg = NULL; | |
277 | replacement_op->common.node = | |
278 | op->common.node; | |
279 | prev->common.next = | |
280 | replacement_op; | |
281 | replacement_op->common.next = | |
282 | op->common.next; | |
283 | next = NULL; | |
284 | } else { | |
285 | prev->common.next = | |
286 | op->common.next; | |
287 | next = NULL; | |
288 | } | |
1da177e4 | 289 | } |
4be44fcd | 290 | prev = next; |
1da177e4 | 291 | } |
1da177e4 LT |
292 | } |
293 | ||
4be44fcd | 294 | cleanup: |
1da177e4 | 295 | |
44f6c012 | 296 | /* Now we can actually delete the subtree rooted at Op */ |
1da177e4 | 297 | |
4be44fcd LB |
298 | acpi_ps_delete_parse_tree(op); |
299 | return_ACPI_STATUS(AE_OK); | |
88ac00f5 | 300 | |
4be44fcd | 301 | allocate_error: |
88ac00f5 RM |
302 | |
303 | /* Always delete the subtree, even on error */ | |
304 | ||
4be44fcd LB |
305 | acpi_ps_delete_parse_tree(op); |
306 | return_ACPI_STATUS(AE_NO_MEMORY); | |
1da177e4 LT |
307 | } |
308 | ||
1da177e4 LT |
309 | /******************************************************************************* |
310 | * | |
311 | * FUNCTION: acpi_ps_next_parse_state | |
312 | * | |
44f6c012 RM |
313 | * PARAMETERS: walk_state - Current state |
314 | * Op - Current parse op | |
315 | * callback_status - Status from previous operation | |
1da177e4 LT |
316 | * |
317 | * RETURN: Status | |
318 | * | |
319 | * DESCRIPTION: Update the parser state based upon the return exception from | |
320 | * the parser callback. | |
321 | * | |
322 | ******************************************************************************/ | |
323 | ||
73459f73 | 324 | acpi_status |
4be44fcd LB |
325 | acpi_ps_next_parse_state(struct acpi_walk_state *walk_state, |
326 | union acpi_parse_object *op, | |
327 | acpi_status callback_status) | |
1da177e4 | 328 | { |
4be44fcd LB |
329 | struct acpi_parse_state *parser_state = &walk_state->parser_state; |
330 | acpi_status status = AE_CTRL_PENDING; | |
1da177e4 | 331 | |
4be44fcd | 332 | ACPI_FUNCTION_TRACE_PTR("ps_next_parse_state", op); |
1da177e4 LT |
333 | |
334 | switch (callback_status) { | |
335 | case AE_CTRL_TERMINATE: | |
1da177e4 LT |
336 | /* |
337 | * A control method was terminated via a RETURN statement. | |
338 | * The walk of this method is complete. | |
339 | */ | |
340 | parser_state->aml = parser_state->aml_end; | |
341 | status = AE_CTRL_TERMINATE; | |
342 | break; | |
343 | ||
1da177e4 LT |
344 | case AE_CTRL_BREAK: |
345 | ||
346 | parser_state->aml = walk_state->aml_last_while; | |
347 | walk_state->control_state->common.value = FALSE; | |
defba1d8 BM |
348 | status = acpi_ds_result_stack_pop(walk_state); |
349 | if (ACPI_SUCCESS(status)) { | |
350 | status = AE_CTRL_BREAK; | |
351 | } | |
1da177e4 LT |
352 | break; |
353 | ||
354 | case AE_CTRL_CONTINUE: | |
355 | ||
1da177e4 | 356 | parser_state->aml = walk_state->aml_last_while; |
defba1d8 BM |
357 | status = acpi_ds_result_stack_pop(walk_state); |
358 | if (ACPI_SUCCESS(status)) { | |
359 | status = AE_CTRL_CONTINUE; | |
360 | } | |
1da177e4 LT |
361 | break; |
362 | ||
363 | case AE_CTRL_PENDING: | |
364 | ||
365 | parser_state->aml = walk_state->aml_last_while; | |
366 | break; | |
367 | ||
368 | #if 0 | |
369 | case AE_CTRL_SKIP: | |
370 | ||
371 | parser_state->aml = parser_state->scope->parse_scope.pkg_end; | |
372 | status = AE_OK; | |
373 | break; | |
374 | #endif | |
375 | ||
376 | case AE_CTRL_TRUE: | |
1da177e4 LT |
377 | /* |
378 | * Predicate of an IF was true, and we are at the matching ELSE. | |
379 | * Just close out this package | |
380 | */ | |
4be44fcd | 381 | parser_state->aml = acpi_ps_get_next_package_end(parser_state); |
defba1d8 BM |
382 | status = acpi_ds_result_stack_pop(walk_state); |
383 | if (ACPI_SUCCESS(status)) { | |
384 | status = AE_CTRL_PENDING; | |
385 | } | |
1da177e4 LT |
386 | break; |
387 | ||
1da177e4 | 388 | case AE_CTRL_FALSE: |
1da177e4 LT |
389 | /* |
390 | * Either an IF/WHILE Predicate was false or we encountered a BREAK | |
391 | * opcode. In both cases, we do not execute the rest of the | |
392 | * package; We simply close out the parent (finishing the walk of | |
393 | * this branch of the tree) and continue execution at the parent | |
394 | * level. | |
395 | */ | |
396 | parser_state->aml = parser_state->scope->parse_scope.pkg_end; | |
397 | ||
398 | /* In the case of a BREAK, just force a predicate (if any) to FALSE */ | |
399 | ||
400 | walk_state->control_state->common.value = FALSE; | |
401 | status = AE_CTRL_END; | |
402 | break; | |
403 | ||
1da177e4 LT |
404 | case AE_CTRL_TRANSFER: |
405 | ||
44f6c012 RM |
406 | /* A method call (invocation) -- transfer control */ |
407 | ||
1da177e4 LT |
408 | status = AE_CTRL_TRANSFER; |
409 | walk_state->prev_op = op; | |
410 | walk_state->method_call_op = op; | |
4be44fcd LB |
411 | walk_state->method_call_node = |
412 | (op->common.value.arg)->common.node; | |
1da177e4 LT |
413 | |
414 | /* Will return value (if any) be used by the caller? */ | |
415 | ||
4be44fcd LB |
416 | walk_state->return_used = |
417 | acpi_ds_is_result_used(op, walk_state); | |
1da177e4 LT |
418 | break; |
419 | ||
1da177e4 | 420 | default: |
44f6c012 | 421 | |
1da177e4 LT |
422 | status = callback_status; |
423 | if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) { | |
424 | status = AE_OK; | |
425 | } | |
426 | break; | |
427 | } | |
428 | ||
4be44fcd | 429 | return_ACPI_STATUS(status); |
1da177e4 LT |
430 | } |
431 | ||
1da177e4 LT |
432 | /******************************************************************************* |
433 | * | |
434 | * FUNCTION: acpi_ps_parse_aml | |
435 | * | |
44f6c012 | 436 | * PARAMETERS: walk_state - Current state |
1da177e4 LT |
437 | * |
438 | * | |
439 | * RETURN: Status | |
440 | * | |
441 | * DESCRIPTION: Parse raw AML and return a tree of ops | |
442 | * | |
443 | ******************************************************************************/ | |
444 | ||
4be44fcd | 445 | acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state) |
1da177e4 | 446 | { |
4be44fcd | 447 | acpi_status status; |
4be44fcd LB |
448 | struct acpi_thread_state *thread; |
449 | struct acpi_thread_state *prev_walk_list = acpi_gbl_current_walk_list; | |
450 | struct acpi_walk_state *previous_walk_state; | |
1da177e4 | 451 | |
4be44fcd | 452 | ACPI_FUNCTION_TRACE("ps_parse_aml"); |
1da177e4 | 453 | |
4be44fcd LB |
454 | ACPI_DEBUG_PRINT((ACPI_DB_PARSE, |
455 | "Entered with walk_state=%p Aml=%p size=%X\n", | |
456 | walk_state, walk_state->parser_state.aml, | |
457 | walk_state->parser_state.aml_size)); | |
1da177e4 LT |
458 | |
459 | /* Create and initialize a new thread state */ | |
460 | ||
4be44fcd | 461 | thread = acpi_ut_create_thread_state(); |
1da177e4 | 462 | if (!thread) { |
4be44fcd | 463 | return_ACPI_STATUS(AE_NO_MEMORY); |
1da177e4 LT |
464 | } |
465 | ||
466 | walk_state->thread = thread; | |
4be44fcd | 467 | acpi_ds_push_walk_state(walk_state, thread); |
1da177e4 LT |
468 | |
469 | /* | |
470 | * This global allows the AML debugger to get a handle to the currently | |
471 | * executing control method. | |
472 | */ | |
473 | acpi_gbl_current_walk_list = thread; | |
474 | ||
475 | /* | |
476 | * Execute the walk loop as long as there is a valid Walk State. This | |
477 | * handles nested control method invocations without recursion. | |
478 | */ | |
4be44fcd | 479 | ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state)); |
1da177e4 LT |
480 | |
481 | status = AE_OK; | |
482 | while (walk_state) { | |
4be44fcd | 483 | if (ACPI_SUCCESS(status)) { |
1da177e4 LT |
484 | /* |
485 | * The parse_loop executes AML until the method terminates | |
486 | * or calls another method. | |
487 | */ | |
4be44fcd | 488 | status = acpi_ps_parse_loop(walk_state); |
1da177e4 LT |
489 | } |
490 | ||
4be44fcd LB |
491 | ACPI_DEBUG_PRINT((ACPI_DB_PARSE, |
492 | "Completed one call to walk loop, %s State=%p\n", | |
493 | acpi_format_exception(status), walk_state)); | |
1da177e4 LT |
494 | |
495 | if (status == AE_CTRL_TRANSFER) { | |
496 | /* | |
497 | * A method call was detected. | |
498 | * Transfer control to the called control method | |
499 | */ | |
4be44fcd LB |
500 | status = |
501 | acpi_ds_call_control_method(thread, walk_state, | |
502 | NULL); | |
1da177e4 LT |
503 | |
504 | /* | |
505 | * If the transfer to the new method method call worked, a new walk | |
506 | * state was created -- get it | |
507 | */ | |
4be44fcd | 508 | walk_state = acpi_ds_get_current_walk_state(thread); |
1da177e4 | 509 | continue; |
4be44fcd | 510 | } else if (status == AE_CTRL_TERMINATE) { |
1da177e4 | 511 | status = AE_OK; |
4be44fcd | 512 | } else if ((status != AE_OK) && (walk_state->method_desc)) { |
c51a4de8 | 513 | /* Either the method parse or actual execution failed */ |
1da177e4 | 514 | |
b8e4d893 BM |
515 | ACPI_ERROR_METHOD("Method parse/execution failed", |
516 | walk_state->method_node, NULL, | |
517 | status); | |
aff8c277 | 518 | |
1da177e4 LT |
519 | /* Check for possible multi-thread reentrancy problem */ |
520 | ||
521 | if ((status == AE_ALREADY_EXISTS) && | |
4be44fcd | 522 | (!walk_state->method_desc->method.semaphore)) { |
1da177e4 | 523 | /* |
c51a4de8 BM |
524 | * Method tried to create an object twice. The probable cause is |
525 | * that the method cannot handle reentrancy. | |
526 | * | |
527 | * The method is marked not_serialized, but it tried to create | |
44f6c012 | 528 | * a named object, causing the second thread entrance to fail. |
c51a4de8 | 529 | * Workaround this problem by marking the method permanently |
44f6c012 | 530 | * as Serialized. |
1da177e4 | 531 | */ |
4be44fcd LB |
532 | walk_state->method_desc->method.method_flags |= |
533 | AML_METHOD_SERIALIZED; | |
1da177e4 LT |
534 | walk_state->method_desc->method.concurrency = 1; |
535 | } | |
536 | } | |
537 | ||
1da177e4 LT |
538 | /* We are done with this walk, move on to the parent if any */ |
539 | ||
4be44fcd | 540 | walk_state = acpi_ds_pop_walk_state(thread); |
1da177e4 LT |
541 | |
542 | /* Reset the current scope to the beginning of scope stack */ | |
543 | ||
4be44fcd | 544 | acpi_ds_scope_stack_clear(walk_state); |
1da177e4 LT |
545 | |
546 | /* | |
c51a4de8 BM |
547 | * If we just returned from the execution of a control method or if we |
548 | * encountered an error during the method parse phase, there's lots of | |
549 | * cleanup to do | |
1da177e4 | 550 | */ |
c51a4de8 BM |
551 | if (((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == |
552 | ACPI_PARSE_EXECUTE) || (ACPI_FAILURE(status))) { | |
aff8c277 RM |
553 | if (walk_state->method_desc) { |
554 | /* Decrement the thread count on the method parse tree */ | |
a94f1881 | 555 | |
c51a4de8 BM |
556 | if (walk_state->method_desc->method. |
557 | thread_count) { | |
558 | walk_state->method_desc->method. | |
559 | thread_count--; | |
560 | } else { | |
b8e4d893 BM |
561 | ACPI_ERROR((AE_INFO, |
562 | "Invalid zero thread count in method")); | |
c51a4de8 | 563 | } |
1da177e4 | 564 | } |
aff8c277 RM |
565 | |
566 | acpi_ds_terminate_control_method(walk_state); | |
1da177e4 LT |
567 | } |
568 | ||
569 | /* Delete this walk state and all linked control states */ | |
570 | ||
4be44fcd | 571 | acpi_ps_cleanup_scope(&walk_state->parser_state); |
1da177e4 LT |
572 | previous_walk_state = walk_state; |
573 | ||
4be44fcd LB |
574 | ACPI_DEBUG_PRINT((ACPI_DB_PARSE, |
575 | "return_value=%p, implicit_value=%p State=%p\n", | |
576 | walk_state->return_desc, | |
577 | walk_state->implicit_return_obj, walk_state)); | |
1da177e4 LT |
578 | |
579 | /* Check if we have restarted a preempted walk */ | |
580 | ||
4be44fcd | 581 | walk_state = acpi_ds_get_current_walk_state(thread); |
1da177e4 | 582 | if (walk_state) { |
4be44fcd | 583 | if (ACPI_SUCCESS(status)) { |
1da177e4 LT |
584 | /* |
585 | * There is another walk state, restart it. | |
586 | * If the method return value is not used by the parent, | |
587 | * The object is deleted | |
588 | */ | |
589 | if (!previous_walk_state->return_desc) { | |
4be44fcd LB |
590 | status = |
591 | acpi_ds_restart_control_method | |
592 | (walk_state, | |
593 | previous_walk_state-> | |
594 | implicit_return_obj); | |
595 | } else { | |
1da177e4 LT |
596 | /* |
597 | * We have a valid return value, delete any implicit | |
598 | * return value. | |
599 | */ | |
4be44fcd LB |
600 | acpi_ds_clear_implicit_return |
601 | (previous_walk_state); | |
1da177e4 | 602 | |
4be44fcd LB |
603 | status = |
604 | acpi_ds_restart_control_method | |
605 | (walk_state, | |
606 | previous_walk_state->return_desc); | |
1da177e4 | 607 | } |
4be44fcd LB |
608 | if (ACPI_SUCCESS(status)) { |
609 | walk_state->walk_type |= | |
610 | ACPI_WALK_METHOD_RESTART; | |
1da177e4 | 611 | } |
4be44fcd | 612 | } else { |
1da177e4 LT |
613 | /* On error, delete any return object */ |
614 | ||
4be44fcd LB |
615 | acpi_ut_remove_reference(previous_walk_state-> |
616 | return_desc); | |
1da177e4 LT |
617 | } |
618 | } | |
619 | ||
620 | /* | |
621 | * Just completed a 1st-level method, save the final internal return | |
622 | * value (if any) | |
623 | */ | |
624 | else if (previous_walk_state->caller_return_desc) { | |
625 | if (previous_walk_state->implicit_return_obj) { | |
44f6c012 | 626 | *(previous_walk_state->caller_return_desc) = |
4be44fcd LB |
627 | previous_walk_state->implicit_return_obj; |
628 | } else { | |
629 | /* NULL if no return value */ | |
1da177e4 | 630 | |
44f6c012 | 631 | *(previous_walk_state->caller_return_desc) = |
4be44fcd | 632 | previous_walk_state->return_desc; |
1da177e4 | 633 | } |
4be44fcd | 634 | } else { |
1da177e4 LT |
635 | if (previous_walk_state->return_desc) { |
636 | /* Caller doesn't want it, must delete it */ | |
637 | ||
4be44fcd LB |
638 | acpi_ut_remove_reference(previous_walk_state-> |
639 | return_desc); | |
1da177e4 LT |
640 | } |
641 | if (previous_walk_state->implicit_return_obj) { | |
642 | /* Caller doesn't want it, must delete it */ | |
643 | ||
4be44fcd LB |
644 | acpi_ut_remove_reference(previous_walk_state-> |
645 | implicit_return_obj); | |
1da177e4 LT |
646 | } |
647 | } | |
648 | ||
4be44fcd | 649 | acpi_ds_delete_walk_state(previous_walk_state); |
1da177e4 LT |
650 | } |
651 | ||
652 | /* Normal exit */ | |
653 | ||
4be44fcd LB |
654 | acpi_ex_release_all_mutexes(thread); |
655 | acpi_ut_delete_generic_state(ACPI_CAST_PTR | |
656 | (union acpi_generic_state, thread)); | |
1da177e4 | 657 | acpi_gbl_current_walk_list = prev_walk_list; |
4be44fcd | 658 | return_ACPI_STATUS(status); |
1da177e4 | 659 | } |