err.no Git - linux-2.6/blob - drivers/acpi/parser/psparse.c

   1 /******************************************************************************
   2  *
   3  * Module Name: psparse - Parser top level AML parse routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2005, R. Byron Moore
   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
  45 /*
  46  * Parse the AML and build an operation tree as most interpreters,
  47  * like Perl, do.  Parsing is done by hand rather than with a YACC
  48  * generated parser to tightly constrain stack and dynamic memory
  49  * usage.  At the same time, parsing is kept flexible and the code
  50  * fairly compact by parsing based on a list of AML opcode
  51  * templates in aml_op_info[]
  52  */
  53
  54 #include <acpi/acpi.h>
  55 #include <acpi/acparser.h>
  56 #include <acpi/acdispat.h>
  57 #include <acpi/amlcode.h>
  58 #include <acpi/acnamesp.h>
  59 #include <acpi/acinterp.h>
  60
  61 #define _COMPONENT          ACPI_PARSER
  62          ACPI_MODULE_NAME    ("psparse")
  63
  64
  65 /*******************************************************************************
  66  *
  67  * FUNCTION:    acpi_ps_get_opcode_size
  68  *
  69  * PARAMETERS:  Opcode          - An AML opcode
  70  *
  71  * RETURN:      Size of the opcode, in bytes (1 or 2)
  72  *
  73  * DESCRIPTION: Get the size of the current opcode.
  74  *
  75  ******************************************************************************/
  76
  77 u32
  78 acpi_ps_get_opcode_size (
  79         u32                             opcode)
  80 {
  81
  82         /* Extended (2-byte) opcode if > 255 */
  83
  84         if (opcode > 0x00FF) {
  85                 return (2);
  86         }
  87
  88         /* Otherwise, just a single byte opcode */
  89
  90         return (1);
  91 }
  92
  93
  94 /*******************************************************************************
  95  *
  96  * FUNCTION:    acpi_ps_peek_opcode
  97  *
  98  * PARAMETERS:  parser_state        - A parser state object
  99  *
 100  * RETURN:      Next AML opcode
 101  *
 102  * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
 103  *
 104  ******************************************************************************/
 105
 106 u16
 107 acpi_ps_peek_opcode (
 108         struct acpi_parse_state         *parser_state)
 109 {
 110         u8                              *aml;
 111         u16                             opcode;
 112
 113
 114         aml = parser_state->aml;
 115         opcode = (u16) ACPI_GET8 (aml);
 116
 117         if (opcode == AML_EXTENDED_OP_PREFIX) {
 118                 /* Extended opcode, get the second opcode byte */
 119
 120                 aml++;
 121                 opcode = (u16) ((opcode << 8) | ACPI_GET8 (aml));
 122         }
 123
 124         return (opcode);
 125 }
 126
 127
 128 /*******************************************************************************
 129  *
 130  * FUNCTION:    acpi_ps_complete_this_op
 131  *
 132  * PARAMETERS:  walk_state      - Current State
 133  *              Op              - Op to complete
 134  *
 135  * RETURN:      Status
 136  *
 137  * DESCRIPTION: Perform any cleanup at the completion of an Op.
 138  *
 139  ******************************************************************************/
 140
 141 acpi_status
 142 acpi_ps_complete_this_op (
 143         struct acpi_walk_state          *walk_state,
 144         union acpi_parse_object         *op)
 145 {
 146         union acpi_parse_object         *prev;
 147         union acpi_parse_object         *next;
 148         const struct acpi_opcode_info   *parent_info;
 149         union acpi_parse_object         *replacement_op = NULL;
 150
 151
 152         ACPI_FUNCTION_TRACE_PTR ("ps_complete_this_op", op);
 153
 154
 155         /* Check for null Op, can happen if AML code is corrupt */
 156
 157         if (!op) {
 158                 return_ACPI_STATUS (AE_OK);  /* OK for now */
 159         }
 160
 161         /* Delete this op and the subtree below it if asked to */
 162
 163         if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) != ACPI_PARSE_DELETE_TREE) ||
 164                  (walk_state->op_info->class == AML_CLASS_ARGUMENT)) {
 165                 return_ACPI_STATUS (AE_OK);
 166         }
 167
 168         /* Make sure that we only delete this subtree */
 169
 170         if (op->common.parent) {
 171                 prev = op->common.parent->common.value.arg;
 172                 if (!prev) {
 173                         /* Nothing more to do */
 174
 175                         goto cleanup;
 176                 }
 177
 178                 /*
 179                  * Check if we need to replace the operator and its subtree
 180                  * with a return value op (placeholder op)
 181                  */
 182                 parent_info = acpi_ps_get_opcode_info (op->common.parent->common.aml_opcode);
 183
 184                 switch (parent_info->class) {
 185                 case AML_CLASS_CONTROL:
 186                         break;
 187
 188                 case AML_CLASS_CREATE:
 189
 190                         /*
 191                          * These opcodes contain term_arg operands. The current
 192                          * op must be replaced by a placeholder return op
 193                          */
 194                         replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
 195                         if (!replacement_op) {
 196                                 goto allocate_error;
 197                         }
 198                         break;
 199
 200                 case AML_CLASS_NAMED_OBJECT:
 201
 202                         /*
 203                          * These opcodes contain term_arg operands. The current
 204                          * op must be replaced by a placeholder return op
 205                          */
 206                         if ((op->common.parent->common.aml_opcode == AML_REGION_OP)      ||
 207                                 (op->common.parent->common.aml_opcode == AML_DATA_REGION_OP) ||
 208                                 (op->common.parent->common.aml_opcode == AML_BUFFER_OP)      ||
 209                                 (op->common.parent->common.aml_opcode == AML_PACKAGE_OP)     ||
 210                                 (op->common.parent->common.aml_opcode == AML_VAR_PACKAGE_OP)) {
 211                                 replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
 212                                 if (!replacement_op) {
 213                                         goto allocate_error;
 214                                 }
 215                         }
 216                         else if ((op->common.parent->common.aml_opcode == AML_NAME_OP) &&
 217                                          (walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2)) {
 218                                 if ((op->common.aml_opcode == AML_BUFFER_OP) ||
 219                                         (op->common.aml_opcode == AML_PACKAGE_OP) ||
 220                                         (op->common.aml_opcode == AML_VAR_PACKAGE_OP)) {
 221                                         replacement_op = acpi_ps_alloc_op (op->common.aml_opcode);
 222                                         if (!replacement_op) {
 223                                                 goto allocate_error;
 224                                         }
 225
 226                                         replacement_op->named.data = op->named.data;
 227                                         replacement_op->named.length = op->named.length;
 228                                 }
 229                         }
 230                         break;
 231
 232                 default:
 233
 234                         replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
 235                         if (!replacement_op) {
 236                                 goto allocate_error;
 237                         }
 238                 }
 239
 240                 /* We must unlink this op from the parent tree */
 241
 242                 if (prev == op) {
 243                         /* This op is the first in the list */
 244
 245                         if (replacement_op) {
 246                                 replacement_op->common.parent       = op->common.parent;
 247                                 replacement_op->common.value.arg    = NULL;
 248                                 replacement_op->common.node         = op->common.node;
 249                                 op->common.parent->common.value.arg = replacement_op;
 250                                 replacement_op->common.next         = op->common.next;
 251                         }
 252                         else {
 253                                 op->common.parent->common.value.arg = op->common.next;
 254                         }
 255                 }
 256
 257                 /* Search the parent list */
 258
 259                 else while (prev) {
 260                         /* Traverse all siblings in the parent's argument list */
 261
 262                         next = prev->common.next;
 263                         if (next == op) {
 264                                 if (replacement_op) {
 265                                         replacement_op->common.parent   = op->common.parent;
 266                                         replacement_op->common.value.arg = NULL;
 267                                         replacement_op->common.node     = op->common.node;
 268                                         prev->common.next               = replacement_op;
 269                                         replacement_op->common.next     = op->common.next;
 270                                         next = NULL;
 271                                 }
 272                                 else {
 273                                         prev->common.next = op->common.next;
 274                                         next = NULL;
 275                                 }
 276                         }
 277                         prev = next;
 278                 }
 279         }
 280
 281
 282 cleanup:
 283
 284         /* Now we can actually delete the subtree rooted at Op */
 285
 286         acpi_ps_delete_parse_tree (op);
 287         return_ACPI_STATUS (AE_OK);
 288
 289
 290 allocate_error:
 291
 292         /* Always delete the subtree, even on error */
 293
 294         acpi_ps_delete_parse_tree (op);
 295         return_ACPI_STATUS (AE_NO_MEMORY);
 296 }
 297
 298
 299 /*******************************************************************************
 300  *
 301  * FUNCTION:    acpi_ps_next_parse_state
 302  *
 303  * PARAMETERS:  walk_state          - Current state
 304  *              Op                  - Current parse op
 305  *              callback_status     - Status from previous operation
 306  *
 307  * RETURN:      Status
 308  *
 309  * DESCRIPTION: Update the parser state based upon the return exception from
 310  *              the parser callback.
 311  *
 312  ******************************************************************************/
 313
 314 acpi_status
 315 acpi_ps_next_parse_state (
 316         struct acpi_walk_state          *walk_state,
 317         union acpi_parse_object         *op,
 318         acpi_status                     callback_status)
 319 {
 320         struct acpi_parse_state         *parser_state = &walk_state->parser_state;
 321         acpi_status                     status = AE_CTRL_PENDING;
 322
 323
 324         ACPI_FUNCTION_TRACE_PTR ("ps_next_parse_state", op);
 325
 326
 327         switch (callback_status) {
 328         case AE_CTRL_TERMINATE:
 329
 330                 /*
 331                  * A control method was terminated via a RETURN statement.
 332                  * The walk of this method is complete.
 333                  */
 334                 parser_state->aml = parser_state->aml_end;
 335                 status = AE_CTRL_TERMINATE;
 336                 break;
 337
 338
 339         case AE_CTRL_BREAK:
 340
 341                 parser_state->aml = walk_state->aml_last_while;
 342                 walk_state->control_state->common.value = FALSE;
 343                 status = AE_CTRL_BREAK;
 344                 break;
 345
 346         case AE_CTRL_CONTINUE:
 347
 348
 349                 parser_state->aml = walk_state->aml_last_while;
 350                 status = AE_CTRL_CONTINUE;
 351                 break;
 352
 353         case AE_CTRL_PENDING:
 354
 355                 parser_state->aml = walk_state->aml_last_while;
 356                 break;
 357
 358 #if 0
 359         case AE_CTRL_SKIP:
 360
 361                 parser_state->aml = parser_state->scope->parse_scope.pkg_end;
 362                 status = AE_OK;
 363                 break;
 364 #endif
 365
 366         case AE_CTRL_TRUE:
 367
 368                 /*
 369                  * Predicate of an IF was true, and we are at the matching ELSE.
 370                  * Just close out this package
 371                  */
 372                 parser_state->aml = acpi_ps_get_next_package_end (parser_state);
 373                 break;
 374
 375
 376         case AE_CTRL_FALSE:
 377
 378                 /*
 379                  * Either an IF/WHILE Predicate was false or we encountered a BREAK
 380                  * opcode.  In both cases, we do not execute the rest of the
 381                  * package;  We simply close out the parent (finishing the walk of
 382                  * this branch of the tree) and continue execution at the parent
 383                  * level.
 384                  */
 385                 parser_state->aml = parser_state->scope->parse_scope.pkg_end;
 386
 387                 /* In the case of a BREAK, just force a predicate (if any) to FALSE */
 388
 389                 walk_state->control_state->common.value = FALSE;
 390                 status = AE_CTRL_END;
 391                 break;
 392
 393
 394         case AE_CTRL_TRANSFER:
 395
 396                 /* A method call (invocation) -- transfer control */
 397
 398                 status = AE_CTRL_TRANSFER;
 399                 walk_state->prev_op = op;
 400                 walk_state->method_call_op = op;
 401                 walk_state->method_call_node = (op->common.value.arg)->common.node;
 402
 403                 /* Will return value (if any) be used by the caller? */
 404
 405                 walk_state->return_used = acpi_ds_is_result_used (op, walk_state);
 406                 break;
 407
 408
 409         default:
 410
 411                 status = callback_status;
 412                 if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) {
 413                         status = AE_OK;
 414                 }
 415                 break;
 416         }
 417
 418         return_ACPI_STATUS (status);
 419 }
 420
 421
 422 /*******************************************************************************
 423  *
 424  * FUNCTION:    acpi_ps_parse_aml
 425  *
 426  * PARAMETERS:  walk_state      - Current state
 427  *
 428  *
 429  * RETURN:      Status
 430  *
 431  * DESCRIPTION: Parse raw AML and return a tree of ops
 432  *
 433  ******************************************************************************/
 434
 435 acpi_status
 436 acpi_ps_parse_aml (
 437         struct acpi_walk_state          *walk_state)
 438 {
 439         acpi_status                     status;
 440         acpi_status                     terminate_status;
 441         struct acpi_thread_state        *thread;
 442         struct acpi_thread_state        *prev_walk_list = acpi_gbl_current_walk_list;
 443         struct acpi_walk_state          *previous_walk_state;
 444
 445
 446         ACPI_FUNCTION_TRACE ("ps_parse_aml");
 447
 448         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
 449                 "Entered with walk_state=%p Aml=%p size=%X\n",
 450                 walk_state, walk_state->parser_state.aml,
 451                 walk_state->parser_state.aml_size));
 452
 453
 454         /* Create and initialize a new thread state */
 455
 456         thread = acpi_ut_create_thread_state ();
 457         if (!thread) {
 458                 return_ACPI_STATUS (AE_NO_MEMORY);
 459         }
 460
 461         walk_state->thread = thread;
 462         acpi_ds_push_walk_state (walk_state, thread);
 463
 464         /*
 465          * This global allows the AML debugger to get a handle to the currently
 466          * executing control method.
 467          */
 468         acpi_gbl_current_walk_list = thread;
 469
 470         /*
 471          * Execute the walk loop as long as there is a valid Walk State.  This
 472          * handles nested control method invocations without recursion.
 473          */
 474         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "State=%p\n", walk_state));
 475
 476         status = AE_OK;
 477         while (walk_state) {
 478                 if (ACPI_SUCCESS (status)) {
 479                         /*
 480                          * The parse_loop executes AML until the method terminates
 481                          * or calls another method.
 482                          */
 483                         status = acpi_ps_parse_loop (walk_state);
 484                 }
 485
 486                 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
 487                         "Completed one call to walk loop, %s State=%p\n",
 488                         acpi_format_exception (status), walk_state));
 489
 490                 if (status == AE_CTRL_TRANSFER) {
 491                         /*
 492                          * A method call was detected.
 493                          * Transfer control to the called control method
 494                          */
 495                         status = acpi_ds_call_control_method (thread, walk_state, NULL);
 496
 497                         /*
 498                          * If the transfer to the new method method call worked, a new walk
 499                          * state was created -- get it
 500                          */
 501                         walk_state = acpi_ds_get_current_walk_state (thread);
 502                         continue;
 503                 }
 504                 else if (status == AE_CTRL_TERMINATE) {
 505                         status = AE_OK;
 506                 }
 507                 else if ((status != AE_OK) && (walk_state->method_desc)) {
 508                         ACPI_REPORT_METHOD_ERROR ("Method execution failed",
 509                                 walk_state->method_node, NULL, status);
 510
 511                         /* Check for possible multi-thread reentrancy problem */
 512
 513                         if ((status == AE_ALREADY_EXISTS) &&
 514                                 (!walk_state->method_desc->method.semaphore)) {
 515                                 /*
 516                                  * This method is marked not_serialized, but it tried to create
 517                                  * a named object, causing the second thread entrance to fail.
 518                                  * We will workaround this by marking the method permanently
 519                                  * as Serialized.
 520                                  */
 521                                 walk_state->method_desc->method.method_flags |= AML_METHOD_SERIALIZED;
 522                                 walk_state->method_desc->method.concurrency = 1;
 523                         }
 524                 }
 525
 526                 if (walk_state->method_desc) {
 527                         /* Decrement the thread count on the method parse tree */
 528
 529                         if (walk_state->method_desc->method.thread_count) {
 530                                 walk_state->method_desc->method.thread_count--;
 531                         }
 532                 }
 533
 534                 /* We are done with this walk, move on to the parent if any */
 535
 536                 walk_state = acpi_ds_pop_walk_state (thread);
 537
 538                 /* Reset the current scope to the beginning of scope stack */
 539
 540                 acpi_ds_scope_stack_clear (walk_state);
 541
 542                 /*
 543                  * If we just returned from the execution of a control method,
 544                  * there's lots of cleanup to do
 545                  */
 546                 if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == ACPI_PARSE_EXECUTE) {
 547                         terminate_status = acpi_ds_terminate_control_method (walk_state);
 548                         if (ACPI_FAILURE (terminate_status)) {
 549                                 ACPI_REPORT_ERROR ((
 550                                         "Could not terminate control method properly\n"));
 551
 552                                 /* Ignore error and continue */
 553                         }
 554                 }
 555
 556                 /* Delete this walk state and all linked control states */
 557
 558                 acpi_ps_cleanup_scope (&walk_state->parser_state);
 559
 560                 previous_walk_state = walk_state;
 561
 562                 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
 563                         "return_value=%p, implicit_value=%p State=%p\n",
 564                         walk_state->return_desc, walk_state->implicit_return_obj, walk_state));
 565
 566                 /* Check if we have restarted a preempted walk */
 567
 568                 walk_state = acpi_ds_get_current_walk_state (thread);
 569                 if (walk_state) {
 570                         if (ACPI_SUCCESS (status)) {
 571                                 /*
 572                                  * There is another walk state, restart it.
 573                                  * If the method return value is not used by the parent,
 574                                  * The object is deleted
 575                                  */
 576                                 if (!previous_walk_state->return_desc) {
 577                                         status = acpi_ds_restart_control_method (walk_state,
 578                                                          previous_walk_state->implicit_return_obj);
 579                                 }
 580                                 else {
 581                                         /*
 582                                          * We have a valid return value, delete any implicit
 583                                          * return value.
 584                                          */
 585                                         acpi_ds_clear_implicit_return (previous_walk_state);
 586
 587                                         status = acpi_ds_restart_control_method (walk_state,
 588                                                          previous_walk_state->return_desc);
 589                                 }
 590                                 if (ACPI_SUCCESS (status)) {
 591                                         walk_state->walk_type |= ACPI_WALK_METHOD_RESTART;
 592                                 }
 593                         }
 594                         else {
 595                                 /* On error, delete any return object */
 596
 597                                 acpi_ut_remove_reference (previous_walk_state->return_desc);
 598                         }
 599                 }
 600
 601                 /*
 602                  * Just completed a 1st-level method, save the final internal return
 603                  * value (if any)
 604                  */
 605                 else if (previous_walk_state->caller_return_desc) {
 606                         if (previous_walk_state->implicit_return_obj) {
 607                                 *(previous_walk_state->caller_return_desc) =
 608                                         previous_walk_state->implicit_return_obj;
 609                         }
 610                         else {
 611                                  /* NULL if no return value */
 612
 613                                 *(previous_walk_state->caller_return_desc) =
 614                                         previous_walk_state->return_desc;
 615                         }
 616                 }
 617                 else {
 618                         if (previous_walk_state->return_desc) {
 619                                 /* Caller doesn't want it, must delete it */
 620
 621                                 acpi_ut_remove_reference (previous_walk_state->return_desc);
 622                         }
 623                         if (previous_walk_state->implicit_return_obj) {
 624                                 /* Caller doesn't want it, must delete it */
 625
 626                                 acpi_ut_remove_reference (previous_walk_state->implicit_return_obj);
 627                         }
 628                 }
 629
 630                 acpi_ds_delete_walk_state (previous_walk_state);
 631         }
 632
 633         /* Normal exit */
 634
 635         acpi_ex_release_all_mutexes (thread);
 636         acpi_ut_delete_generic_state (ACPI_CAST_PTR (union acpi_generic_state, thread));
 637         acpi_gbl_current_walk_list = prev_walk_list;
 638         return_ACPI_STATUS (status);
 639 }
 640
 641