psargs.c revision b4e104eaeb8cd4329a23e0e4ebf166681b1d182d
1/****************************************************************************** 2 * 3 * Module Name: psargs - Parse AML opcode arguments 4 * 5 *****************************************************************************/ 6 7/* 8 * Copyright (C) 2000 - 2011, 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 "acparser.h" 47#include "amlcode.h" 48#include "acnamesp.h" 49#include "acdispat.h" 50 51#define _COMPONENT ACPI_PARSER 52ACPI_MODULE_NAME("psargs") 53 54/* Local prototypes */ 55static u32 56acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state); 57 58static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state 59 *parser_state); 60 61/******************************************************************************* 62 * 63 * FUNCTION: acpi_ps_get_next_package_length 64 * 65 * PARAMETERS: parser_state - Current parser state object 66 * 67 * RETURN: Decoded package length. On completion, the AML pointer points 68 * past the length byte or bytes. 69 * 70 * DESCRIPTION: Decode and return a package length field. 71 * Note: Largest package length is 28 bits, from ACPI specification 72 * 73 ******************************************************************************/ 74 75static u32 76acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state) 77{ 78 u8 *aml = parser_state->aml; 79 u32 package_length = 0; 80 u32 byte_count; 81 u8 byte_zero_mask = 0x3F; /* Default [0:5] */ 82 83 ACPI_FUNCTION_TRACE(ps_get_next_package_length); 84 85 /* 86 * Byte 0 bits [6:7] contain the number of additional bytes 87 * used to encode the package length, either 0,1,2, or 3 88 */ 89 byte_count = (aml[0] >> 6); 90 parser_state->aml += ((acpi_size) byte_count + 1); 91 92 /* Get bytes 3, 2, 1 as needed */ 93 94 while (byte_count) { 95 /* 96 * Final bit positions for the package length bytes: 97 * Byte3->[20:27] 98 * Byte2->[12:19] 99 * Byte1->[04:11] 100 * Byte0->[00:03] 101 */ 102 package_length |= (aml[byte_count] << ((byte_count << 3) - 4)); 103 104 byte_zero_mask = 0x0F; /* Use bits [0:3] of byte 0 */ 105 byte_count--; 106 } 107 108 /* Byte 0 is a special case, either bits [0:3] or [0:5] are used */ 109 110 package_length |= (aml[0] & byte_zero_mask); 111 return_UINT32(package_length); 112} 113 114/******************************************************************************* 115 * 116 * FUNCTION: acpi_ps_get_next_package_end 117 * 118 * PARAMETERS: parser_state - Current parser state object 119 * 120 * RETURN: Pointer to end-of-package +1 121 * 122 * DESCRIPTION: Get next package length and return a pointer past the end of 123 * the package. Consumes the package length field 124 * 125 ******************************************************************************/ 126 127u8 *acpi_ps_get_next_package_end(struct acpi_parse_state *parser_state) 128{ 129 u8 *start = parser_state->aml; 130 u32 package_length; 131 132 ACPI_FUNCTION_TRACE(ps_get_next_package_end); 133 134 /* Function below updates parser_state->Aml */ 135 136 package_length = acpi_ps_get_next_package_length(parser_state); 137 138 return_PTR(start + package_length); /* end of package */ 139} 140 141/******************************************************************************* 142 * 143 * FUNCTION: acpi_ps_get_next_namestring 144 * 145 * PARAMETERS: parser_state - Current parser state object 146 * 147 * RETURN: Pointer to the start of the name string (pointer points into 148 * the AML. 149 * 150 * DESCRIPTION: Get next raw namestring within the AML stream. Handles all name 151 * prefix characters. Set parser state to point past the string. 152 * (Name is consumed from the AML.) 153 * 154 ******************************************************************************/ 155 156char *acpi_ps_get_next_namestring(struct acpi_parse_state *parser_state) 157{ 158 u8 *start = parser_state->aml; 159 u8 *end = parser_state->aml; 160 161 ACPI_FUNCTION_TRACE(ps_get_next_namestring); 162 163 /* Point past any namestring prefix characters (backslash or carat) */ 164 165 while (acpi_ps_is_prefix_char(*end)) { 166 end++; 167 } 168 169 /* Decode the path prefix character */ 170 171 switch (*end) { 172 case 0: 173 174 /* null_name */ 175 176 if (end == start) { 177 start = NULL; 178 } 179 end++; 180 break; 181 182 case AML_DUAL_NAME_PREFIX: 183 184 /* Two name segments */ 185 186 end += 1 + (2 * ACPI_NAME_SIZE); 187 break; 188 189 case AML_MULTI_NAME_PREFIX_OP: 190 191 /* Multiple name segments, 4 chars each, count in next byte */ 192 193 end += 2 + (*(end + 1) * ACPI_NAME_SIZE); 194 break; 195 196 default: 197 198 /* Single name segment */ 199 200 end += ACPI_NAME_SIZE; 201 break; 202 } 203 204 parser_state->aml = end; 205 return_PTR((char *)start); 206} 207 208/******************************************************************************* 209 * 210 * FUNCTION: acpi_ps_get_next_namepath 211 * 212 * PARAMETERS: parser_state - Current parser state object 213 * Arg - Where the namepath will be stored 214 * arg_count - If the namepath points to a control method 215 * the method's argument is returned here. 216 * possible_method_call - Whether the namepath can possibly be the 217 * start of a method call 218 * 219 * RETURN: Status 220 * 221 * DESCRIPTION: Get next name (if method call, return # of required args). 222 * Names are looked up in the internal namespace to determine 223 * if the name represents a control method. If a method 224 * is found, the number of arguments to the method is returned. 225 * This information is critical for parsing to continue correctly. 226 * 227 ******************************************************************************/ 228 229acpi_status 230acpi_ps_get_next_namepath(struct acpi_walk_state *walk_state, 231 struct acpi_parse_state *parser_state, 232 union acpi_parse_object *arg, u8 possible_method_call) 233{ 234 acpi_status status; 235 char *path; 236 union acpi_parse_object *name_op; 237 union acpi_operand_object *method_desc; 238 struct acpi_namespace_node *node; 239 u8 *start = parser_state->aml; 240 241 ACPI_FUNCTION_TRACE(ps_get_next_namepath); 242 243 path = acpi_ps_get_next_namestring(parser_state); 244 acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP); 245 246 /* Null path case is allowed, just exit */ 247 248 if (!path) { 249 arg->common.value.name = path; 250 return_ACPI_STATUS(AE_OK); 251 } 252 253 /* 254 * Lookup the name in the internal namespace, starting with the current 255 * scope. We don't want to add anything new to the namespace here, 256 * however, so we use MODE_EXECUTE. 257 * Allow searching of the parent tree, but don't open a new scope - 258 * we just want to lookup the object (must be mode EXECUTE to perform 259 * the upsearch) 260 */ 261 status = acpi_ns_lookup(walk_state->scope_info, path, 262 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 263 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, 264 NULL, &node); 265 266 /* 267 * If this name is a control method invocation, we must 268 * setup the method call 269 */ 270 if (ACPI_SUCCESS(status) && 271 possible_method_call && (node->type == ACPI_TYPE_METHOD)) { 272 if (walk_state->opcode == AML_UNLOAD_OP) { 273 /* 274 * acpi_ps_get_next_namestring has increased the AML pointer, 275 * so we need to restore the saved AML pointer for method call. 276 */ 277 walk_state->parser_state.aml = start; 278 walk_state->arg_count = 1; 279 acpi_ps_init_op(arg, AML_INT_METHODCALL_OP); 280 return_ACPI_STATUS(AE_OK); 281 } 282 283 /* This name is actually a control method invocation */ 284 285 method_desc = acpi_ns_get_attached_object(node); 286 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 287 "Control Method - %p Desc %p Path=%p\n", node, 288 method_desc, path)); 289 290 name_op = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP); 291 if (!name_op) { 292 return_ACPI_STATUS(AE_NO_MEMORY); 293 } 294 295 /* Change Arg into a METHOD CALL and attach name to it */ 296 297 acpi_ps_init_op(arg, AML_INT_METHODCALL_OP); 298 name_op->common.value.name = path; 299 300 /* Point METHODCALL/NAME to the METHOD Node */ 301 302 name_op->common.node = node; 303 acpi_ps_append_arg(arg, name_op); 304 305 if (!method_desc) { 306 ACPI_ERROR((AE_INFO, 307 "Control Method %p has no attached object", 308 node)); 309 return_ACPI_STATUS(AE_AML_INTERNAL); 310 } 311 312 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 313 "Control Method - %p Args %X\n", 314 node, method_desc->method.param_count)); 315 316 /* Get the number of arguments to expect */ 317 318 walk_state->arg_count = method_desc->method.param_count; 319 return_ACPI_STATUS(AE_OK); 320 } 321 322 /* 323 * Special handling if the name was not found during the lookup - 324 * some not_found cases are allowed 325 */ 326 if (status == AE_NOT_FOUND) { 327 328 /* 1) not_found is ok during load pass 1/2 (allow forward references) */ 329 330 if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) != 331 ACPI_PARSE_EXECUTE) { 332 status = AE_OK; 333 } 334 335 /* 2) not_found during a cond_ref_of(x) is ok by definition */ 336 337 else if (walk_state->op->common.aml_opcode == 338 AML_COND_REF_OF_OP) { 339 status = AE_OK; 340 } 341 342 /* 343 * 3) not_found while building a Package is ok at this point, we 344 * may flag as an error later if slack mode is not enabled. 345 * (Some ASL code depends on allowing this behavior) 346 */ 347 else if ((arg->common.parent) && 348 ((arg->common.parent->common.aml_opcode == 349 AML_PACKAGE_OP) 350 || (arg->common.parent->common.aml_opcode == 351 AML_VAR_PACKAGE_OP))) { 352 status = AE_OK; 353 } 354 } 355 356 /* Final exception check (may have been changed from code above) */ 357 358 if (ACPI_FAILURE(status)) { 359 ACPI_ERROR_NAMESPACE(path, status); 360 361 if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == 362 ACPI_PARSE_EXECUTE) { 363 364 /* Report a control method execution error */ 365 366 status = acpi_ds_method_error(status, walk_state); 367 } 368 } 369 370 /* Save the namepath */ 371 372 arg->common.value.name = path; 373 return_ACPI_STATUS(status); 374} 375 376/******************************************************************************* 377 * 378 * FUNCTION: acpi_ps_get_next_simple_arg 379 * 380 * PARAMETERS: parser_state - Current parser state object 381 * arg_type - The argument type (AML_*_ARG) 382 * Arg - Where the argument is returned 383 * 384 * RETURN: None 385 * 386 * DESCRIPTION: Get the next simple argument (constant, string, or namestring) 387 * 388 ******************************************************************************/ 389 390void 391acpi_ps_get_next_simple_arg(struct acpi_parse_state *parser_state, 392 u32 arg_type, union acpi_parse_object *arg) 393{ 394 u32 length; 395 u16 opcode; 396 u8 *aml = parser_state->aml; 397 398 ACPI_FUNCTION_TRACE_U32(ps_get_next_simple_arg, arg_type); 399 400 switch (arg_type) { 401 case ARGP_BYTEDATA: 402 403 /* Get 1 byte from the AML stream */ 404 405 opcode = AML_BYTE_OP; 406 arg->common.value.integer = (u64) *aml; 407 length = 1; 408 break; 409 410 case ARGP_WORDDATA: 411 412 /* Get 2 bytes from the AML stream */ 413 414 opcode = AML_WORD_OP; 415 ACPI_MOVE_16_TO_64(&arg->common.value.integer, aml); 416 length = 2; 417 break; 418 419 case ARGP_DWORDDATA: 420 421 /* Get 4 bytes from the AML stream */ 422 423 opcode = AML_DWORD_OP; 424 ACPI_MOVE_32_TO_64(&arg->common.value.integer, aml); 425 length = 4; 426 break; 427 428 case ARGP_QWORDDATA: 429 430 /* Get 8 bytes from the AML stream */ 431 432 opcode = AML_QWORD_OP; 433 ACPI_MOVE_64_TO_64(&arg->common.value.integer, aml); 434 length = 8; 435 break; 436 437 case ARGP_CHARLIST: 438 439 /* Get a pointer to the string, point past the string */ 440 441 opcode = AML_STRING_OP; 442 arg->common.value.string = ACPI_CAST_PTR(char, aml); 443 444 /* Find the null terminator */ 445 446 length = 0; 447 while (aml[length]) { 448 length++; 449 } 450 length++; 451 break; 452 453 case ARGP_NAME: 454 case ARGP_NAMESTRING: 455 456 acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP); 457 arg->common.value.name = 458 acpi_ps_get_next_namestring(parser_state); 459 return_VOID; 460 461 default: 462 463 ACPI_ERROR((AE_INFO, "Invalid ArgType 0x%X", arg_type)); 464 return_VOID; 465 } 466 467 acpi_ps_init_op(arg, opcode); 468 parser_state->aml += length; 469 return_VOID; 470} 471 472/******************************************************************************* 473 * 474 * FUNCTION: acpi_ps_get_next_field 475 * 476 * PARAMETERS: parser_state - Current parser state object 477 * 478 * RETURN: A newly allocated FIELD op 479 * 480 * DESCRIPTION: Get next field (named_field, reserved_field, or access_field) 481 * 482 ******************************************************************************/ 483 484static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state 485 *parser_state) 486{ 487 u32 aml_offset = (u32) 488 ACPI_PTR_DIFF(parser_state->aml, 489 parser_state->aml_start); 490 union acpi_parse_object *field; 491 u16 opcode; 492 u32 name; 493 494 ACPI_FUNCTION_TRACE(ps_get_next_field); 495 496 /* Determine field type */ 497 498 switch (ACPI_GET8(parser_state->aml)) { 499 default: 500 501 opcode = AML_INT_NAMEDFIELD_OP; 502 break; 503 504 case 0x00: 505 506 opcode = AML_INT_RESERVEDFIELD_OP; 507 parser_state->aml++; 508 break; 509 510 case 0x01: 511 512 opcode = AML_INT_ACCESSFIELD_OP; 513 parser_state->aml++; 514 break; 515 } 516 517 /* Allocate a new field op */ 518 519 field = acpi_ps_alloc_op(opcode); 520 if (!field) { 521 return_PTR(NULL); 522 } 523 524 field->common.aml_offset = aml_offset; 525 526 /* Decode the field type */ 527 528 switch (opcode) { 529 case AML_INT_NAMEDFIELD_OP: 530 531 /* Get the 4-character name */ 532 533 ACPI_MOVE_32_TO_32(&name, parser_state->aml); 534 acpi_ps_set_name(field, name); 535 parser_state->aml += ACPI_NAME_SIZE; 536 537 /* Get the length which is encoded as a package length */ 538 539 field->common.value.size = 540 acpi_ps_get_next_package_length(parser_state); 541 break; 542 543 case AML_INT_RESERVEDFIELD_OP: 544 545 /* Get the length which is encoded as a package length */ 546 547 field->common.value.size = 548 acpi_ps_get_next_package_length(parser_state); 549 break; 550 551 case AML_INT_ACCESSFIELD_OP: 552 553 /* 554 * Get access_type and access_attrib and merge into the field Op 555 * access_type is first operand, access_attribute is second 556 */ 557 field->common.value.integer = 558 (((u32) ACPI_GET8(parser_state->aml) << 8)); 559 parser_state->aml++; 560 field->common.value.integer |= ACPI_GET8(parser_state->aml); 561 parser_state->aml++; 562 break; 563 564 default: 565 566 /* Opcode was set in previous switch */ 567 break; 568 } 569 570 return_PTR(field); 571} 572 573/******************************************************************************* 574 * 575 * FUNCTION: acpi_ps_get_next_arg 576 * 577 * PARAMETERS: walk_state - Current state 578 * parser_state - Current parser state object 579 * arg_type - The argument type (AML_*_ARG) 580 * return_arg - Where the next arg is returned 581 * 582 * RETURN: Status, and an op object containing the next argument. 583 * 584 * DESCRIPTION: Get next argument (including complex list arguments that require 585 * pushing the parser stack) 586 * 587 ******************************************************************************/ 588 589acpi_status 590acpi_ps_get_next_arg(struct acpi_walk_state *walk_state, 591 struct acpi_parse_state *parser_state, 592 u32 arg_type, union acpi_parse_object **return_arg) 593{ 594 union acpi_parse_object *arg = NULL; 595 union acpi_parse_object *prev = NULL; 596 union acpi_parse_object *field; 597 u32 subop; 598 acpi_status status = AE_OK; 599 600 ACPI_FUNCTION_TRACE_PTR(ps_get_next_arg, parser_state); 601 602 switch (arg_type) { 603 case ARGP_BYTEDATA: 604 case ARGP_WORDDATA: 605 case ARGP_DWORDDATA: 606 case ARGP_CHARLIST: 607 case ARGP_NAME: 608 case ARGP_NAMESTRING: 609 610 /* Constants, strings, and namestrings are all the same size */ 611 612 arg = acpi_ps_alloc_op(AML_BYTE_OP); 613 if (!arg) { 614 return_ACPI_STATUS(AE_NO_MEMORY); 615 } 616 acpi_ps_get_next_simple_arg(parser_state, arg_type, arg); 617 break; 618 619 case ARGP_PKGLENGTH: 620 621 /* Package length, nothing returned */ 622 623 parser_state->pkg_end = 624 acpi_ps_get_next_package_end(parser_state); 625 break; 626 627 case ARGP_FIELDLIST: 628 629 if (parser_state->aml < parser_state->pkg_end) { 630 631 /* Non-empty list */ 632 633 while (parser_state->aml < parser_state->pkg_end) { 634 field = acpi_ps_get_next_field(parser_state); 635 if (!field) { 636 return_ACPI_STATUS(AE_NO_MEMORY); 637 } 638 639 if (prev) { 640 prev->common.next = field; 641 } else { 642 arg = field; 643 } 644 prev = field; 645 } 646 647 /* Skip to End of byte data */ 648 649 parser_state->aml = parser_state->pkg_end; 650 } 651 break; 652 653 case ARGP_BYTELIST: 654 655 if (parser_state->aml < parser_state->pkg_end) { 656 657 /* Non-empty list */ 658 659 arg = acpi_ps_alloc_op(AML_INT_BYTELIST_OP); 660 if (!arg) { 661 return_ACPI_STATUS(AE_NO_MEMORY); 662 } 663 664 /* Fill in bytelist data */ 665 666 arg->common.value.size = (u32) 667 ACPI_PTR_DIFF(parser_state->pkg_end, 668 parser_state->aml); 669 arg->named.data = parser_state->aml; 670 671 /* Skip to End of byte data */ 672 673 parser_state->aml = parser_state->pkg_end; 674 } 675 break; 676 677 case ARGP_TARGET: 678 case ARGP_SUPERNAME: 679 case ARGP_SIMPLENAME: 680 681 subop = acpi_ps_peek_opcode(parser_state); 682 if (subop == 0 || 683 acpi_ps_is_leading_char(subop) || 684 acpi_ps_is_prefix_char(subop)) { 685 686 /* null_name or name_string */ 687 688 arg = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP); 689 if (!arg) { 690 return_ACPI_STATUS(AE_NO_MEMORY); 691 } 692 693 /* To support super_name arg of Unload */ 694 695 if (walk_state->opcode == AML_UNLOAD_OP) { 696 status = 697 acpi_ps_get_next_namepath(walk_state, 698 parser_state, arg, 699 1); 700 701 /* 702 * If the super_name arg of Unload is a method call, 703 * we have restored the AML pointer, just free this Arg 704 */ 705 if (arg->common.aml_opcode == 706 AML_INT_METHODCALL_OP) { 707 acpi_ps_free_op(arg); 708 arg = NULL; 709 } 710 } else { 711 status = 712 acpi_ps_get_next_namepath(walk_state, 713 parser_state, arg, 714 0); 715 } 716 } else { 717 /* Single complex argument, nothing returned */ 718 719 walk_state->arg_count = 1; 720 } 721 break; 722 723 case ARGP_DATAOBJ: 724 case ARGP_TERMARG: 725 726 /* Single complex argument, nothing returned */ 727 728 walk_state->arg_count = 1; 729 break; 730 731 case ARGP_DATAOBJLIST: 732 case ARGP_TERMLIST: 733 case ARGP_OBJLIST: 734 735 if (parser_state->aml < parser_state->pkg_end) { 736 737 /* Non-empty list of variable arguments, nothing returned */ 738 739 walk_state->arg_count = ACPI_VAR_ARGS; 740 } 741 break; 742 743 default: 744 745 ACPI_ERROR((AE_INFO, "Invalid ArgType: 0x%X", arg_type)); 746 status = AE_AML_OPERAND_TYPE; 747 break; 748 } 749 750 *return_arg = arg; 751 return_ACPI_STATUS(status); 752} 753