1 /****************************************************************************** 2 * 3 * Module Name: dsmethod - Parser/Interpreter interface - control method parsing 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2018, Intel Corp. 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 44 #include <acpi/acpi.h> 45 #include "accommon.h" 46 #include "acdispat.h" 47 #include "acinterp.h" 48 #include "acnamesp.h" 49 #include "acparser.h" 50 #include "amlcode.h" 51 #include "acdebug.h" 52 53 #define _COMPONENT ACPI_DISPATCHER 54 ACPI_MODULE_NAME("dsmethod") 55 56 /* Local prototypes */ 57 static acpi_status 58 acpi_ds_detect_named_opcodes(struct acpi_walk_state *walk_state, 59 union acpi_parse_object **out_op); 60 61 static acpi_status 62 acpi_ds_create_method_mutex(union acpi_operand_object *method_desc); 63 64 /******************************************************************************* 65 * 66 * FUNCTION: acpi_ds_auto_serialize_method 67 * 68 * PARAMETERS: node - Namespace Node of the method 69 * obj_desc - Method object attached to node 70 * 71 * RETURN: Status 72 * 73 * DESCRIPTION: Parse a control method AML to scan for control methods that 74 * need serialization due to the creation of named objects. 75 * 76 * NOTE: It is a bit of overkill to mark all such methods serialized, since 77 * there is only a problem if the method actually blocks during execution. 78 * A blocking operation is, for example, a Sleep() operation, or any access 79 * to an operation region. However, it is probably not possible to easily 80 * detect whether a method will block or not, so we simply mark all suspicious 81 * methods as serialized. 82 * 83 * NOTE2: This code is essentially a generic routine for parsing a single 84 * control method. 85 * 86 ******************************************************************************/ 87 88 acpi_status 89 acpi_ds_auto_serialize_method(struct acpi_namespace_node *node, 90 union acpi_operand_object *obj_desc) 91 { 92 acpi_status status; 93 union acpi_parse_object *op = NULL; 94 struct acpi_walk_state *walk_state; 95 96 ACPI_FUNCTION_TRACE_PTR(ds_auto_serialize_method, node); 97 98 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 99 "Method auto-serialization parse [%4.4s] %p\n", 100 acpi_ut_get_node_name(node), node)); 101 102 /* Create/Init a root op for the method parse tree */ 103 104 op = acpi_ps_alloc_op(AML_METHOD_OP, obj_desc->method.aml_start); 105 if (!op) { 106 return_ACPI_STATUS(AE_NO_MEMORY); 107 } 108 109 acpi_ps_set_name(op, node->name.integer); 110 op->common.node = node; 111 112 /* Create and initialize a new walk state */ 113 114 walk_state = 115 acpi_ds_create_walk_state(node->owner_id, NULL, NULL, NULL); 116 if (!walk_state) { 117 acpi_ps_free_op(op); 118 return_ACPI_STATUS(AE_NO_MEMORY); 119 } 120 121 status = acpi_ds_init_aml_walk(walk_state, op, node, 122 obj_desc->method.aml_start, 123 obj_desc->method.aml_length, NULL, 0); 124 if (ACPI_FAILURE(status)) { 125 acpi_ds_delete_walk_state(walk_state); 126 acpi_ps_free_op(op); 127 return_ACPI_STATUS(status); 128 } 129 130 walk_state->descending_callback = acpi_ds_detect_named_opcodes; 131 132 /* Parse the method, scan for creation of named objects */ 133 134 status = acpi_ps_parse_aml(walk_state); 135 136 acpi_ps_delete_parse_tree(op); 137 return_ACPI_STATUS(status); 138 } 139 140 /******************************************************************************* 141 * 142 * FUNCTION: acpi_ds_detect_named_opcodes 143 * 144 * PARAMETERS: walk_state - Current state of the parse tree walk 145 * out_op - Unused, required for parser interface 146 * 147 * RETURN: Status 148 * 149 * DESCRIPTION: Descending callback used during the loading of ACPI tables. 150 * Currently used to detect methods that must be marked serialized 151 * in order to avoid problems with the creation of named objects. 152 * 153 ******************************************************************************/ 154 155 static acpi_status 156 acpi_ds_detect_named_opcodes(struct acpi_walk_state *walk_state, 157 union acpi_parse_object **out_op) 158 { 159 160 ACPI_FUNCTION_NAME(acpi_ds_detect_named_opcodes); 161 162 /* We are only interested in opcodes that create a new name */ 163 164 if (! 165 (walk_state->op_info-> 166 flags & (AML_NAMED | AML_CREATE | AML_FIELD))) { 167 return (AE_OK); 168 } 169 170 /* 171 * At this point, we know we have a Named object opcode. 172 * Mark the method as serialized. Later code will create a mutex for 173 * this method to enforce serialization. 174 * 175 * Note, ACPI_METHOD_IGNORE_SYNC_LEVEL flag means that we will ignore the 176 * Sync Level mechanism for this method, even though it is now serialized. 177 * Otherwise, there can be conflicts with existing ASL code that actually 178 * uses sync levels. 179 */ 180 walk_state->method_desc->method.sync_level = 0; 181 walk_state->method_desc->method.info_flags |= 182 (ACPI_METHOD_SERIALIZED | ACPI_METHOD_IGNORE_SYNC_LEVEL); 183 184 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 185 "Method serialized [%4.4s] %p - [%s] (%4.4X)\n", 186 walk_state->method_node->name.ascii, 187 walk_state->method_node, walk_state->op_info->name, 188 walk_state->opcode)); 189 190 /* Abort the parse, no need to examine this method any further */ 191 192 return (AE_CTRL_TERMINATE); 193 } 194 195 /******************************************************************************* 196 * 197 * FUNCTION: acpi_ds_method_error 198 * 199 * PARAMETERS: status - Execution status 200 * walk_state - Current state 201 * 202 * RETURN: Status 203 * 204 * DESCRIPTION: Called on method error. Invoke the global exception handler if 205 * present, dump the method data if the debugger is configured 206 * 207 * Note: Allows the exception handler to change the status code 208 * 209 ******************************************************************************/ 210 211 acpi_status 212 acpi_ds_method_error(acpi_status status, struct acpi_walk_state *walk_state) 213 { 214 u32 aml_offset; 215 acpi_name name = 0; 216 217 ACPI_FUNCTION_ENTRY(); 218 219 /* Ignore AE_OK and control exception codes */ 220 221 if (ACPI_SUCCESS(status) || (status & AE_CODE_CONTROL)) { 222 return (status); 223 } 224 225 /* Invoke the global exception handler */ 226 227 if (acpi_gbl_exception_handler) { 228 229 /* Exit the interpreter, allow handler to execute methods */ 230 231 acpi_ex_exit_interpreter(); 232 233 /* 234 * Handler can map the exception code to anything it wants, including 235 * AE_OK, in which case the executing method will not be aborted. 236 */ 237 aml_offset = (u32)ACPI_PTR_DIFF(walk_state->aml, 238 walk_state->parser_state. 239 aml_start); 240 241 if (walk_state->method_node) { 242 name = walk_state->method_node->name.integer; 243 } else if (walk_state->deferred_node) { 244 name = walk_state->deferred_node->name.integer; 245 } 246 247 status = acpi_gbl_exception_handler(status, name, 248 walk_state->opcode, 249 aml_offset, NULL); 250 acpi_ex_enter_interpreter(); 251 } 252 253 acpi_ds_clear_implicit_return(walk_state); 254 255 if (ACPI_FAILURE(status)) { 256 acpi_ds_dump_method_stack(status, walk_state, walk_state->op); 257 258 /* Display method locals/args if debugger is present */ 259 260 #ifdef ACPI_DEBUGGER 261 acpi_db_dump_method_info(status, walk_state); 262 #endif 263 } 264 265 return (status); 266 } 267 268 /******************************************************************************* 269 * 270 * FUNCTION: acpi_ds_create_method_mutex 271 * 272 * PARAMETERS: obj_desc - The method object 273 * 274 * RETURN: Status 275 * 276 * DESCRIPTION: Create a mutex object for a serialized control method 277 * 278 ******************************************************************************/ 279 280 static acpi_status 281 acpi_ds_create_method_mutex(union acpi_operand_object *method_desc) 282 { 283 union acpi_operand_object *mutex_desc; 284 acpi_status status; 285 286 ACPI_FUNCTION_TRACE(ds_create_method_mutex); 287 288 /* Create the new mutex object */ 289 290 mutex_desc = acpi_ut_create_internal_object(ACPI_TYPE_MUTEX); 291 if (!mutex_desc) { 292 return_ACPI_STATUS(AE_NO_MEMORY); 293 } 294 295 /* Create the actual OS Mutex */ 296 297 status = acpi_os_create_mutex(&mutex_desc->mutex.os_mutex); 298 if (ACPI_FAILURE(status)) { 299 acpi_ut_delete_object_desc(mutex_desc); 300 return_ACPI_STATUS(status); 301 } 302 303 mutex_desc->mutex.sync_level = method_desc->method.sync_level; 304 method_desc->method.mutex = mutex_desc; 305 return_ACPI_STATUS(AE_OK); 306 } 307 308 /******************************************************************************* 309 * 310 * FUNCTION: acpi_ds_begin_method_execution 311 * 312 * PARAMETERS: method_node - Node of the method 313 * obj_desc - The method object 314 * walk_state - current state, NULL if not yet executing 315 * a method. 316 * 317 * RETURN: Status 318 * 319 * DESCRIPTION: Prepare a method for execution. Parses the method if necessary, 320 * increments the thread count, and waits at the method semaphore 321 * for clearance to execute. 322 * 323 ******************************************************************************/ 324 325 acpi_status 326 acpi_ds_begin_method_execution(struct acpi_namespace_node *method_node, 327 union acpi_operand_object *obj_desc, 328 struct acpi_walk_state *walk_state) 329 { 330 acpi_status status = AE_OK; 331 332 ACPI_FUNCTION_TRACE_PTR(ds_begin_method_execution, method_node); 333 334 if (!method_node) { 335 return_ACPI_STATUS(AE_NULL_ENTRY); 336 } 337 338 acpi_ex_start_trace_method(method_node, obj_desc, walk_state); 339 340 /* Prevent wraparound of thread count */ 341 342 if (obj_desc->method.thread_count == ACPI_UINT8_MAX) { 343 ACPI_ERROR((AE_INFO, 344 "Method reached maximum reentrancy limit (255)")); 345 return_ACPI_STATUS(AE_AML_METHOD_LIMIT); 346 } 347 348 /* 349 * If this method is serialized, we need to acquire the method mutex. 350 */ 351 if (obj_desc->method.info_flags & ACPI_METHOD_SERIALIZED) { 352 /* 353 * Create a mutex for the method if it is defined to be Serialized 354 * and a mutex has not already been created. We defer the mutex creation 355 * until a method is actually executed, to minimize the object count 356 */ 357 if (!obj_desc->method.mutex) { 358 status = acpi_ds_create_method_mutex(obj_desc); 359 if (ACPI_FAILURE(status)) { 360 return_ACPI_STATUS(status); 361 } 362 } 363 364 /* 365 * The current_sync_level (per-thread) must be less than or equal to 366 * the sync level of the method. This mechanism provides some 367 * deadlock prevention. 368 * 369 * If the method was auto-serialized, we just ignore the sync level 370 * mechanism, because auto-serialization of methods can interfere 371 * with ASL code that actually uses sync levels. 372 * 373 * Top-level method invocation has no walk state at this point 374 */ 375 if (walk_state && 376 (!(obj_desc->method. 377 info_flags & ACPI_METHOD_IGNORE_SYNC_LEVEL)) 378 && (walk_state->thread->current_sync_level > 379 obj_desc->method.mutex->mutex.sync_level)) { 380 ACPI_ERROR((AE_INFO, 381 "Cannot acquire Mutex for method [%4.4s]" 382 ", current SyncLevel is too large (%u)", 383 acpi_ut_get_node_name(method_node), 384 walk_state->thread->current_sync_level)); 385 386 return_ACPI_STATUS(AE_AML_MUTEX_ORDER); 387 } 388 389 /* 390 * Obtain the method mutex if necessary. Do not acquire mutex for a 391 * recursive call. 392 */ 393 if (!walk_state || 394 !obj_desc->method.mutex->mutex.thread_id || 395 (walk_state->thread->thread_id != 396 obj_desc->method.mutex->mutex.thread_id)) { 397 /* 398 * Acquire the method mutex. This releases the interpreter if we 399 * block (and reacquires it before it returns) 400 */ 401 status = 402 acpi_ex_system_wait_mutex(obj_desc->method.mutex-> 403 mutex.os_mutex, 404 ACPI_WAIT_FOREVER); 405 if (ACPI_FAILURE(status)) { 406 return_ACPI_STATUS(status); 407 } 408 409 /* Update the mutex and walk info and save the original sync_level */ 410 411 if (walk_state) { 412 obj_desc->method.mutex->mutex. 413 original_sync_level = 414 walk_state->thread->current_sync_level; 415 416 obj_desc->method.mutex->mutex.thread_id = 417 walk_state->thread->thread_id; 418 419 /* 420 * Update the current sync_level only if this is not an auto- 421 * serialized method. In the auto case, we have to ignore 422 * the sync level for the method mutex (created for the 423 * auto-serialization) because we have no idea of what the 424 * sync level should be. Therefore, just ignore it. 425 */ 426 if (!(obj_desc->method.info_flags & 427 ACPI_METHOD_IGNORE_SYNC_LEVEL)) { 428 walk_state->thread->current_sync_level = 429 obj_desc->method.sync_level; 430 } 431 } else { 432 obj_desc->method.mutex->mutex. 433 original_sync_level = 434 obj_desc->method.mutex->mutex.sync_level; 435 436 obj_desc->method.mutex->mutex.thread_id = 437 acpi_os_get_thread_id(); 438 } 439 } 440 441 /* Always increase acquisition depth */ 442 443 obj_desc->method.mutex->mutex.acquisition_depth++; 444 } 445 446 /* 447 * Allocate an Owner ID for this method, only if this is the first thread 448 * to begin concurrent execution. We only need one owner_id, even if the 449 * method is invoked recursively. 450 */ 451 if (!obj_desc->method.owner_id) { 452 status = acpi_ut_allocate_owner_id(&obj_desc->method.owner_id); 453 if (ACPI_FAILURE(status)) { 454 goto cleanup; 455 } 456 } 457 458 /* 459 * Increment the method parse tree thread count since it has been 460 * reentered one more time (even if it is the same thread) 461 */ 462 obj_desc->method.thread_count++; 463 acpi_method_count++; 464 return_ACPI_STATUS(status); 465 466 cleanup: 467 /* On error, must release the method mutex (if present) */ 468 469 if (obj_desc->method.mutex) { 470 acpi_os_release_mutex(obj_desc->method.mutex->mutex.os_mutex); 471 } 472 return_ACPI_STATUS(status); 473 } 474 475 /******************************************************************************* 476 * 477 * FUNCTION: acpi_ds_call_control_method 478 * 479 * PARAMETERS: thread - Info for this thread 480 * this_walk_state - Current walk state 481 * op - Current Op to be walked 482 * 483 * RETURN: Status 484 * 485 * DESCRIPTION: Transfer execution to a called control method 486 * 487 ******************************************************************************/ 488 489 acpi_status 490 acpi_ds_call_control_method(struct acpi_thread_state *thread, 491 struct acpi_walk_state *this_walk_state, 492 union acpi_parse_object *op) 493 { 494 acpi_status status; 495 struct acpi_namespace_node *method_node; 496 struct acpi_walk_state *next_walk_state = NULL; 497 union acpi_operand_object *obj_desc; 498 struct acpi_evaluate_info *info; 499 u32 i; 500 501 ACPI_FUNCTION_TRACE_PTR(ds_call_control_method, this_walk_state); 502 503 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, 504 "Calling method %p, currentstate=%p\n", 505 this_walk_state->prev_op, this_walk_state)); 506 507 /* 508 * Get the namespace entry for the control method we are about to call 509 */ 510 method_node = this_walk_state->method_call_node; 511 if (!method_node) { 512 return_ACPI_STATUS(AE_NULL_ENTRY); 513 } 514 515 obj_desc = acpi_ns_get_attached_object(method_node); 516 if (!obj_desc) { 517 return_ACPI_STATUS(AE_NULL_OBJECT); 518 } 519 520 /* Init for new method, possibly wait on method mutex */ 521 522 status = 523 acpi_ds_begin_method_execution(method_node, obj_desc, 524 this_walk_state); 525 if (ACPI_FAILURE(status)) { 526 return_ACPI_STATUS(status); 527 } 528 529 /* Begin method parse/execution. Create a new walk state */ 530 531 next_walk_state = 532 acpi_ds_create_walk_state(obj_desc->method.owner_id, NULL, obj_desc, 533 thread); 534 if (!next_walk_state) { 535 status = AE_NO_MEMORY; 536 goto cleanup; 537 } 538 539 /* 540 * The resolved arguments were put on the previous walk state's operand 541 * stack. Operands on the previous walk state stack always 542 * start at index 0. Also, null terminate the list of arguments 543 */ 544 this_walk_state->operands[this_walk_state->num_operands] = NULL; 545 546 /* 547 * Allocate and initialize the evaluation information block 548 * TBD: this is somewhat inefficient, should change interface to 549 * ds_init_aml_walk. For now, keeps this struct off the CPU stack 550 */ 551 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info)); 552 if (!info) { 553 status = AE_NO_MEMORY; 554 goto cleanup; 555 } 556 557 info->parameters = &this_walk_state->operands[0]; 558 559 status = acpi_ds_init_aml_walk(next_walk_state, NULL, method_node, 560 obj_desc->method.aml_start, 561 obj_desc->method.aml_length, info, 562 ACPI_IMODE_EXECUTE); 563 564 ACPI_FREE(info); 565 if (ACPI_FAILURE(status)) { 566 goto cleanup; 567 } 568 569 /* 570 * Delete the operands on the previous walkstate operand stack 571 * (they were copied to new objects) 572 */ 573 for (i = 0; i < obj_desc->method.param_count; i++) { 574 acpi_ut_remove_reference(this_walk_state->operands[i]); 575 this_walk_state->operands[i] = NULL; 576 } 577 578 /* Clear the operand stack */ 579 580 this_walk_state->num_operands = 0; 581 582 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, 583 "**** Begin nested execution of [%4.4s] **** WalkState=%p\n", 584 method_node->name.ascii, next_walk_state)); 585 586 /* Invoke an internal method if necessary */ 587 588 if (obj_desc->method.info_flags & ACPI_METHOD_INTERNAL_ONLY) { 589 status = 590 obj_desc->method.dispatch.implementation(next_walk_state); 591 if (status == AE_OK) { 592 status = AE_CTRL_TERMINATE; 593 } 594 } 595 596 return_ACPI_STATUS(status); 597 598 cleanup: 599 600 /* On error, we must terminate the method properly */ 601 602 acpi_ds_terminate_control_method(obj_desc, next_walk_state); 603 acpi_ds_delete_walk_state(next_walk_state); 604 605 return_ACPI_STATUS(status); 606 } 607 608 /******************************************************************************* 609 * 610 * FUNCTION: acpi_ds_restart_control_method 611 * 612 * PARAMETERS: walk_state - State for preempted method (caller) 613 * return_desc - Return value from the called method 614 * 615 * RETURN: Status 616 * 617 * DESCRIPTION: Restart a method that was preempted by another (nested) method 618 * invocation. Handle the return value (if any) from the callee. 619 * 620 ******************************************************************************/ 621 622 acpi_status 623 acpi_ds_restart_control_method(struct acpi_walk_state *walk_state, 624 union acpi_operand_object *return_desc) 625 { 626 acpi_status status; 627 int same_as_implicit_return; 628 629 ACPI_FUNCTION_TRACE_PTR(ds_restart_control_method, walk_state); 630 631 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, 632 "****Restart [%4.4s] Op %p ReturnValueFromCallee %p\n", 633 acpi_ut_get_node_name(walk_state->method_node), 634 walk_state->method_call_op, return_desc)); 635 636 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, 637 " ReturnFromThisMethodUsed?=%X ResStack %p Walk %p\n", 638 walk_state->return_used, 639 walk_state->results, walk_state)); 640 641 /* Did the called method return a value? */ 642 643 if (return_desc) { 644 645 /* Is the implicit return object the same as the return desc? */ 646 647 same_as_implicit_return = 648 (walk_state->implicit_return_obj == return_desc); 649 650 /* Are we actually going to use the return value? */ 651 652 if (walk_state->return_used) { 653 654 /* Save the return value from the previous method */ 655 656 status = acpi_ds_result_push(return_desc, walk_state); 657 if (ACPI_FAILURE(status)) { 658 acpi_ut_remove_reference(return_desc); 659 return_ACPI_STATUS(status); 660 } 661 662 /* 663 * Save as THIS method's return value in case it is returned 664 * immediately to yet another method 665 */ 666 walk_state->return_desc = return_desc; 667 } 668 669 /* 670 * The following code is the optional support for the so-called 671 * "implicit return". Some AML code assumes that the last value of the 672 * method is "implicitly" returned to the caller, in the absence of an 673 * explicit return value. 674 * 675 * Just save the last result of the method as the return value. 676 * 677 * NOTE: this is optional because the ASL language does not actually 678 * support this behavior. 679 */ 680 else if (!acpi_ds_do_implicit_return 681 (return_desc, walk_state, FALSE) 682 || same_as_implicit_return) { 683 /* 684 * Delete the return value if it will not be used by the 685 * calling method or remove one reference if the explicit return 686 * is the same as the implicit return value. 687 */ 688 acpi_ut_remove_reference(return_desc); 689 } 690 } 691 692 return_ACPI_STATUS(AE_OK); 693 } 694 695 /******************************************************************************* 696 * 697 * FUNCTION: acpi_ds_terminate_control_method 698 * 699 * PARAMETERS: method_desc - Method object 700 * walk_state - State associated with the method 701 * 702 * RETURN: None 703 * 704 * DESCRIPTION: Terminate a control method. Delete everything that the method 705 * created, delete all locals and arguments, and delete the parse 706 * tree if requested. 707 * 708 * MUTEX: Interpreter is locked 709 * 710 ******************************************************************************/ 711 712 void 713 acpi_ds_terminate_control_method(union acpi_operand_object *method_desc, 714 struct acpi_walk_state *walk_state) 715 { 716 717 ACPI_FUNCTION_TRACE_PTR(ds_terminate_control_method, walk_state); 718 719 /* method_desc is required, walk_state is optional */ 720 721 if (!method_desc) { 722 return_VOID; 723 } 724 725 if (walk_state) { 726 727 /* Delete all arguments and locals */ 728 729 acpi_ds_method_data_delete_all(walk_state); 730 731 /* 732 * Delete any namespace objects created anywhere within the 733 * namespace by the execution of this method. Unless: 734 * 1) This method is a module-level executable code method, in which 735 * case we want make the objects permanent. 736 * 2) There are other threads executing the method, in which case we 737 * will wait until the last thread has completed. 738 */ 739 if (!(method_desc->method.info_flags & ACPI_METHOD_MODULE_LEVEL) 740 && (method_desc->method.thread_count == 1)) { 741 742 /* Delete any direct children of (created by) this method */ 743 744 (void)acpi_ex_exit_interpreter(); 745 acpi_ns_delete_namespace_subtree(walk_state-> 746 method_node); 747 (void)acpi_ex_enter_interpreter(); 748 749 /* 750 * Delete any objects that were created by this method 751 * elsewhere in the namespace (if any were created). 752 * Use of the ACPI_METHOD_MODIFIED_NAMESPACE optimizes the 753 * deletion such that we don't have to perform an entire 754 * namespace walk for every control method execution. 755 */ 756 if (method_desc->method. 757 info_flags & ACPI_METHOD_MODIFIED_NAMESPACE) { 758 (void)acpi_ex_exit_interpreter(); 759 acpi_ns_delete_namespace_by_owner(method_desc-> 760 method. 761 owner_id); 762 (void)acpi_ex_enter_interpreter(); 763 method_desc->method.info_flags &= 764 ~ACPI_METHOD_MODIFIED_NAMESPACE; 765 } 766 } 767 768 /* 769 * If method is serialized, release the mutex and restore the 770 * current sync level for this thread 771 */ 772 if (method_desc->method.mutex) { 773 774 /* Acquisition Depth handles recursive calls */ 775 776 method_desc->method.mutex->mutex.acquisition_depth--; 777 if (!method_desc->method.mutex->mutex.acquisition_depth) { 778 walk_state->thread->current_sync_level = 779 method_desc->method.mutex->mutex. 780 original_sync_level; 781 782 acpi_os_release_mutex(method_desc->method. 783 mutex->mutex.os_mutex); 784 method_desc->method.mutex->mutex.thread_id = 0; 785 } 786 } 787 } 788 789 /* Decrement the thread count on the method */ 790 791 if (method_desc->method.thread_count) { 792 method_desc->method.thread_count--; 793 } else { 794 ACPI_ERROR((AE_INFO, "Invalid zero thread count in method")); 795 } 796 797 /* Are there any other threads currently executing this method? */ 798 799 if (method_desc->method.thread_count) { 800 /* 801 * Additional threads. Do not release the owner_id in this case, 802 * we immediately reuse it for the next thread executing this method 803 */ 804 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, 805 "*** Completed execution of one thread, %u threads remaining\n", 806 method_desc->method.thread_count)); 807 } else { 808 /* This is the only executing thread for this method */ 809 810 /* 811 * Support to dynamically change a method from not_serialized to 812 * Serialized if it appears that the method is incorrectly written and 813 * does not support multiple thread execution. The best example of this 814 * is if such a method creates namespace objects and blocks. A second 815 * thread will fail with an AE_ALREADY_EXISTS exception. 816 * 817 * This code is here because we must wait until the last thread exits 818 * before marking the method as serialized. 819 */ 820 if (method_desc->method. 821 info_flags & ACPI_METHOD_SERIALIZED_PENDING) { 822 if (walk_state) { 823 ACPI_INFO(("Marking method %4.4s as Serialized " 824 "because of AE_ALREADY_EXISTS error", 825 walk_state->method_node->name. 826 ascii)); 827 } 828 829 /* 830 * Method tried to create an object twice and was marked as 831 * "pending serialized". The probable cause is that the method 832 * cannot handle reentrancy. 833 * 834 * The method was created as not_serialized, but it tried to create 835 * a named object and then blocked, causing the second thread 836 * entrance to begin and then fail. Workaround this problem by 837 * marking the method permanently as Serialized when the last 838 * thread exits here. 839 */ 840 method_desc->method.info_flags &= 841 ~ACPI_METHOD_SERIALIZED_PENDING; 842 843 method_desc->method.info_flags |= 844 (ACPI_METHOD_SERIALIZED | 845 ACPI_METHOD_IGNORE_SYNC_LEVEL); 846 method_desc->method.sync_level = 0; 847 } 848 849 /* No more threads, we can free the owner_id */ 850 851 if (! 852 (method_desc->method. 853 info_flags & ACPI_METHOD_MODULE_LEVEL)) { 854 acpi_ut_release_owner_id(&method_desc->method.owner_id); 855 } 856 } 857 858 acpi_ex_stop_trace_method((struct acpi_namespace_node *)method_desc-> 859 method.node, method_desc, walk_state); 860 861 return_VOID; 862 } 863