1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 2 /******************************************************************************* 3 * 4 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace 5 * 6 ******************************************************************************/ 7 8 #include <acpi/acpi.h> 9 #include "accommon.h" 10 #include "amlcode.h" 11 #include "acnamesp.h" 12 #include "acdispat.h" 13 14 #ifdef ACPI_ASL_COMPILER 15 #include "acdisasm.h" 16 #endif 17 18 #define _COMPONENT ACPI_NAMESPACE 19 ACPI_MODULE_NAME("nsaccess") 20 21 /******************************************************************************* 22 * 23 * FUNCTION: acpi_ns_root_initialize 24 * 25 * PARAMETERS: None 26 * 27 * RETURN: Status 28 * 29 * DESCRIPTION: Allocate and initialize the default root named objects 30 * 31 * MUTEX: Locks namespace for entire execution 32 * 33 ******************************************************************************/ 34 acpi_status acpi_ns_root_initialize(void) 35 { 36 acpi_status status; 37 const struct acpi_predefined_names *init_val = NULL; 38 struct acpi_namespace_node *new_node; 39 union acpi_operand_object *obj_desc; 40 acpi_string val = NULL; 41 42 ACPI_FUNCTION_TRACE(ns_root_initialize); 43 44 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE); 45 if (ACPI_FAILURE(status)) { 46 return_ACPI_STATUS(status); 47 } 48 49 /* 50 * The global root ptr is initially NULL, so a non-NULL value indicates 51 * that acpi_ns_root_initialize() has already been called; just return. 52 */ 53 if (acpi_gbl_root_node) { 54 status = AE_OK; 55 goto unlock_and_exit; 56 } 57 58 /* 59 * Tell the rest of the subsystem that the root is initialized 60 * (This is OK because the namespace is locked) 61 */ 62 acpi_gbl_root_node = &acpi_gbl_root_node_struct; 63 64 /* Enter the pre-defined names in the name table */ 65 66 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 67 "Entering predefined entries into namespace\n")); 68 69 for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) { 70 71 /* _OSI is optional for now, will be permanent later */ 72 73 if (!strcmp(init_val->name, "_OSI") 74 && !acpi_gbl_create_osi_method) { 75 continue; 76 } 77 78 status = 79 acpi_ns_lookup(NULL, ACPI_CAST_PTR(char, init_val->name), 80 init_val->type, ACPI_IMODE_LOAD_PASS2, 81 ACPI_NS_NO_UPSEARCH, NULL, &new_node); 82 if (ACPI_FAILURE(status)) { 83 ACPI_EXCEPTION((AE_INFO, status, 84 "Could not create predefined name %s", 85 init_val->name)); 86 continue; 87 } 88 89 /* 90 * Name entered successfully. If entry in pre_defined_names[] specifies 91 * an initial value, create the initial value. 92 */ 93 if (init_val->val) { 94 status = acpi_os_predefined_override(init_val, &val); 95 if (ACPI_FAILURE(status)) { 96 ACPI_ERROR((AE_INFO, 97 "Could not override predefined %s", 98 init_val->name)); 99 } 100 101 if (!val) { 102 val = init_val->val; 103 } 104 105 /* 106 * Entry requests an initial value, allocate a 107 * descriptor for it. 108 */ 109 obj_desc = 110 acpi_ut_create_internal_object(init_val->type); 111 if (!obj_desc) { 112 status = AE_NO_MEMORY; 113 goto unlock_and_exit; 114 } 115 116 /* 117 * Convert value string from table entry to 118 * internal representation. Only types actually 119 * used for initial values are implemented here. 120 */ 121 switch (init_val->type) { 122 case ACPI_TYPE_METHOD: 123 124 obj_desc->method.param_count = 125 (u8) ACPI_TO_INTEGER(val); 126 obj_desc->common.flags |= AOPOBJ_DATA_VALID; 127 128 #if defined (ACPI_ASL_COMPILER) 129 130 /* Save the parameter count for the iASL compiler */ 131 132 new_node->value = obj_desc->method.param_count; 133 #else 134 /* Mark this as a very SPECIAL method */ 135 136 obj_desc->method.info_flags = 137 ACPI_METHOD_INTERNAL_ONLY; 138 obj_desc->method.dispatch.implementation = 139 acpi_ut_osi_implementation; 140 #endif 141 break; 142 143 case ACPI_TYPE_INTEGER: 144 145 obj_desc->integer.value = ACPI_TO_INTEGER(val); 146 break; 147 148 case ACPI_TYPE_STRING: 149 150 /* Build an object around the static string */ 151 152 obj_desc->string.length = (u32)strlen(val); 153 obj_desc->string.pointer = val; 154 obj_desc->common.flags |= AOPOBJ_STATIC_POINTER; 155 break; 156 157 case ACPI_TYPE_MUTEX: 158 159 obj_desc->mutex.node = new_node; 160 obj_desc->mutex.sync_level = 161 (u8) (ACPI_TO_INTEGER(val) - 1); 162 163 /* Create a mutex */ 164 165 status = 166 acpi_os_create_mutex(&obj_desc->mutex. 167 os_mutex); 168 if (ACPI_FAILURE(status)) { 169 acpi_ut_remove_reference(obj_desc); 170 goto unlock_and_exit; 171 } 172 173 /* Special case for ACPI Global Lock */ 174 175 if (strcmp(init_val->name, "_GL_") == 0) { 176 acpi_gbl_global_lock_mutex = obj_desc; 177 178 /* Create additional counting semaphore for global lock */ 179 180 status = 181 acpi_os_create_semaphore(1, 0, 182 &acpi_gbl_global_lock_semaphore); 183 if (ACPI_FAILURE(status)) { 184 acpi_ut_remove_reference 185 (obj_desc); 186 goto unlock_and_exit; 187 } 188 } 189 break; 190 191 default: 192 193 ACPI_ERROR((AE_INFO, 194 "Unsupported initial type value 0x%X", 195 init_val->type)); 196 acpi_ut_remove_reference(obj_desc); 197 obj_desc = NULL; 198 continue; 199 } 200 201 /* Store pointer to value descriptor in the Node */ 202 203 status = acpi_ns_attach_object(new_node, obj_desc, 204 obj_desc->common.type); 205 206 /* Remove local reference to the object */ 207 208 acpi_ut_remove_reference(obj_desc); 209 } 210 } 211 212 unlock_and_exit: 213 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE); 214 215 /* Save a handle to "_GPE", it is always present */ 216 217 if (ACPI_SUCCESS(status)) { 218 status = acpi_ns_get_node(NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH, 219 &acpi_gbl_fadt_gpe_device); 220 } 221 222 return_ACPI_STATUS(status); 223 } 224 225 /******************************************************************************* 226 * 227 * FUNCTION: acpi_ns_lookup 228 * 229 * PARAMETERS: scope_info - Current scope info block 230 * pathname - Search pathname, in internal format 231 * (as represented in the AML stream) 232 * type - Type associated with name 233 * interpreter_mode - IMODE_LOAD_PASS2 => add name if not found 234 * flags - Flags describing the search restrictions 235 * walk_state - Current state of the walk 236 * return_node - Where the Node is placed (if found 237 * or created successfully) 238 * 239 * RETURN: Status 240 * 241 * DESCRIPTION: Find or enter the passed name in the name space. 242 * Log an error if name not found in Exec mode. 243 * 244 * MUTEX: Assumes namespace is locked. 245 * 246 ******************************************************************************/ 247 248 acpi_status 249 acpi_ns_lookup(union acpi_generic_state *scope_info, 250 char *pathname, 251 acpi_object_type type, 252 acpi_interpreter_mode interpreter_mode, 253 u32 flags, 254 struct acpi_walk_state *walk_state, 255 struct acpi_namespace_node **return_node) 256 { 257 acpi_status status; 258 char *path = pathname; 259 char *external_path; 260 struct acpi_namespace_node *prefix_node; 261 struct acpi_namespace_node *current_node = NULL; 262 struct acpi_namespace_node *this_node = NULL; 263 u32 num_segments; 264 u32 num_carats; 265 acpi_name simple_name; 266 acpi_object_type type_to_check_for; 267 acpi_object_type this_search_type; 268 u32 search_parent_flag = ACPI_NS_SEARCH_PARENT; 269 u32 local_flags; 270 acpi_interpreter_mode local_interpreter_mode; 271 272 ACPI_FUNCTION_TRACE(ns_lookup); 273 274 if (!return_node) { 275 return_ACPI_STATUS(AE_BAD_PARAMETER); 276 } 277 278 local_flags = flags & 279 ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND | 280 ACPI_NS_SEARCH_PARENT); 281 *return_node = ACPI_ENTRY_NOT_FOUND; 282 acpi_gbl_ns_lookup_count++; 283 284 if (!acpi_gbl_root_node) { 285 return_ACPI_STATUS(AE_NO_NAMESPACE); 286 } 287 288 /* Get the prefix scope. A null scope means use the root scope */ 289 290 if ((!scope_info) || (!scope_info->scope.node)) { 291 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 292 "Null scope prefix, using root node (%p)\n", 293 acpi_gbl_root_node)); 294 295 prefix_node = acpi_gbl_root_node; 296 } else { 297 prefix_node = scope_info->scope.node; 298 if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) != 299 ACPI_DESC_TYPE_NAMED) { 300 ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]", 301 prefix_node, 302 acpi_ut_get_descriptor_name(prefix_node))); 303 return_ACPI_STATUS(AE_AML_INTERNAL); 304 } 305 306 if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) { 307 /* 308 * This node might not be a actual "scope" node (such as a 309 * Device/Method, etc.) It could be a Package or other object 310 * node. Backup up the tree to find the containing scope node. 311 */ 312 while (!acpi_ns_opens_scope(prefix_node->type) && 313 prefix_node->type != ACPI_TYPE_ANY) { 314 prefix_node = prefix_node->parent; 315 } 316 } 317 } 318 319 /* Save type. TBD: may be no longer necessary */ 320 321 type_to_check_for = type; 322 323 /* 324 * Begin examination of the actual pathname 325 */ 326 if (!pathname) { 327 328 /* A Null name_path is allowed and refers to the root */ 329 330 num_segments = 0; 331 this_node = acpi_gbl_root_node; 332 path = ""; 333 334 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 335 "Null Pathname (Zero segments), Flags=%X\n", 336 flags)); 337 } else { 338 /* 339 * Name pointer is valid (and must be in internal name format) 340 * 341 * Check for scope prefixes: 342 * 343 * As represented in the AML stream, a namepath consists of an 344 * optional scope prefix followed by a name segment part. 345 * 346 * If present, the scope prefix is either a Root Prefix (in 347 * which case the name is fully qualified), or one or more 348 * Parent Prefixes (in which case the name's scope is relative 349 * to the current scope). 350 */ 351 if (*path == (u8) AML_ROOT_PREFIX) { 352 353 /* Pathname is fully qualified, start from the root */ 354 355 this_node = acpi_gbl_root_node; 356 search_parent_flag = ACPI_NS_NO_UPSEARCH; 357 358 /* Point to name segment part */ 359 360 path++; 361 362 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 363 "Path is absolute from root [%p]\n", 364 this_node)); 365 } else { 366 /* Pathname is relative to current scope, start there */ 367 368 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 369 "Searching relative to prefix scope [%4.4s] (%p)\n", 370 acpi_ut_get_node_name(prefix_node), 371 prefix_node)); 372 373 /* 374 * Handle multiple Parent Prefixes (carat) by just getting 375 * the parent node for each prefix instance. 376 */ 377 this_node = prefix_node; 378 num_carats = 0; 379 while (*path == (u8) AML_PARENT_PREFIX) { 380 381 /* Name is fully qualified, no search rules apply */ 382 383 search_parent_flag = ACPI_NS_NO_UPSEARCH; 384 385 /* 386 * Point past this prefix to the name segment 387 * part or the next Parent Prefix 388 */ 389 path++; 390 391 /* Backup to the parent node */ 392 393 num_carats++; 394 this_node = this_node->parent; 395 if (!this_node) { 396 /* 397 * Current scope has no parent scope. Externalize 398 * the internal path for error message. 399 */ 400 status = 401 acpi_ns_externalize_name 402 (ACPI_UINT32_MAX, pathname, NULL, 403 &external_path); 404 if (ACPI_SUCCESS(status)) { 405 ACPI_ERROR((AE_INFO, 406 "%s: Path has too many parent prefixes (^)", 407 external_path)); 408 409 ACPI_FREE(external_path); 410 } 411 412 return_ACPI_STATUS(AE_NOT_FOUND); 413 } 414 } 415 416 if (search_parent_flag == ACPI_NS_NO_UPSEARCH) { 417 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 418 "Search scope is [%4.4s], path has %u carat(s)\n", 419 acpi_ut_get_node_name 420 (this_node), num_carats)); 421 } 422 } 423 424 /* 425 * Determine the number of ACPI name segments in this pathname. 426 * 427 * The segment part consists of either: 428 * - A Null name segment (0) 429 * - A dual_name_prefix followed by two 4-byte name segments 430 * - A multi_name_prefix followed by a byte indicating the 431 * number of segments and the segments themselves. 432 * - A single 4-byte name segment 433 * 434 * Examine the name prefix opcode, if any, to determine the number of 435 * segments. 436 */ 437 switch (*path) { 438 case 0: 439 /* 440 * Null name after a root or parent prefixes. We already 441 * have the correct target node and there are no name segments. 442 */ 443 num_segments = 0; 444 type = this_node->type; 445 446 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 447 "Prefix-only Pathname (Zero name segments), Flags=%X\n", 448 flags)); 449 break; 450 451 case AML_DUAL_NAME_PREFIX: 452 453 /* More than one name_seg, search rules do not apply */ 454 455 search_parent_flag = ACPI_NS_NO_UPSEARCH; 456 457 /* Two segments, point to first name segment */ 458 459 num_segments = 2; 460 path++; 461 462 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 463 "Dual Pathname (2 segments, Flags=%X)\n", 464 flags)); 465 break; 466 467 case AML_MULTI_NAME_PREFIX: 468 469 /* More than one name_seg, search rules do not apply */ 470 471 search_parent_flag = ACPI_NS_NO_UPSEARCH; 472 473 /* Extract segment count, point to first name segment */ 474 475 path++; 476 num_segments = (u32) (u8) * path; 477 path++; 478 479 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 480 "Multi Pathname (%u Segments, Flags=%X)\n", 481 num_segments, flags)); 482 break; 483 484 default: 485 /* 486 * Not a Null name, no Dual or Multi prefix, hence there is 487 * only one name segment and Pathname is already pointing to it. 488 */ 489 num_segments = 1; 490 491 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 492 "Simple Pathname (1 segment, Flags=%X)\n", 493 flags)); 494 break; 495 } 496 497 ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path)); 498 } 499 500 /* 501 * Search namespace for each segment of the name. Loop through and 502 * verify (or add to the namespace) each name segment. 503 * 504 * The object type is significant only at the last name 505 * segment. (We don't care about the types along the path, only 506 * the type of the final target object.) 507 */ 508 this_search_type = ACPI_TYPE_ANY; 509 current_node = this_node; 510 511 while (num_segments && current_node) { 512 num_segments--; 513 if (!num_segments) { 514 515 /* This is the last segment, enable typechecking */ 516 517 this_search_type = type; 518 519 /* 520 * Only allow automatic parent search (search rules) if the caller 521 * requested it AND we have a single, non-fully-qualified name_seg 522 */ 523 if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) && 524 (flags & ACPI_NS_SEARCH_PARENT)) { 525 local_flags |= ACPI_NS_SEARCH_PARENT; 526 } 527 528 /* Set error flag according to caller */ 529 530 if (flags & ACPI_NS_ERROR_IF_FOUND) { 531 local_flags |= ACPI_NS_ERROR_IF_FOUND; 532 } 533 534 /* Set override flag according to caller */ 535 536 if (flags & ACPI_NS_OVERRIDE_IF_FOUND) { 537 local_flags |= ACPI_NS_OVERRIDE_IF_FOUND; 538 } 539 } 540 541 /* Handle opcodes that create a new name_seg via a full name_path */ 542 543 local_interpreter_mode = interpreter_mode; 544 if ((flags & ACPI_NS_PREFIX_MUST_EXIST) && (num_segments > 0)) { 545 546 /* Every element of the path must exist (except for the final name_seg) */ 547 548 local_interpreter_mode = ACPI_IMODE_EXECUTE; 549 } 550 551 /* Extract one ACPI name from the front of the pathname */ 552 553 ACPI_MOVE_32_TO_32(&simple_name, path); 554 555 /* Try to find the single (4 character) ACPI name */ 556 557 status = 558 acpi_ns_search_and_enter(simple_name, walk_state, 559 current_node, 560 local_interpreter_mode, 561 this_search_type, local_flags, 562 &this_node); 563 if (ACPI_FAILURE(status)) { 564 if (status == AE_NOT_FOUND) { 565 #if !defined ACPI_ASL_COMPILER /* Note: iASL reports this error by itself, not needed here */ 566 if (flags & ACPI_NS_PREFIX_MUST_EXIST) { 567 acpi_os_printf(ACPI_MSG_BIOS_ERROR 568 "Object does not exist: %4.4s\n", 569 &simple_name); 570 } 571 #endif 572 /* Name not found in ACPI namespace */ 573 574 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 575 "Name [%4.4s] not found in scope [%4.4s] %p\n", 576 (char *)&simple_name, 577 (char *)¤t_node->name, 578 current_node)); 579 } 580 #ifdef ACPI_EXEC_APP 581 if ((status == AE_ALREADY_EXISTS) && 582 (this_node->flags & ANOBJ_NODE_EARLY_INIT)) { 583 this_node->flags &= ~ANOBJ_NODE_EARLY_INIT; 584 status = AE_OK; 585 } 586 #endif 587 588 #ifdef ACPI_ASL_COMPILER 589 /* 590 * If this ACPI name already exists within the namespace as an 591 * external declaration, then mark the external as a conflicting 592 * declaration and proceed to process the current node as if it did 593 * not exist in the namespace. If this node is not processed as 594 * normal, then it could cause improper namespace resolution 595 * by failing to open a new scope. 596 */ 597 if (acpi_gbl_disasm_flag && 598 (status == AE_ALREADY_EXISTS) && 599 ((this_node->flags & ANOBJ_IS_EXTERNAL) || 600 (walk_state 601 && walk_state->opcode == AML_EXTERNAL_OP))) { 602 this_node->flags &= ~ANOBJ_IS_EXTERNAL; 603 this_node->type = (u8)this_search_type; 604 if (walk_state->opcode != AML_EXTERNAL_OP) { 605 acpi_dm_mark_external_conflict 606 (this_node); 607 } 608 break; 609 } 610 #endif 611 612 *return_node = this_node; 613 return_ACPI_STATUS(status); 614 } 615 616 /* More segments to follow? */ 617 618 if (num_segments > 0) { 619 /* 620 * If we have an alias to an object that opens a scope (such as a 621 * device or processor), we need to dereference the alias here so 622 * that we can access any children of the original node (via the 623 * remaining segments). 624 */ 625 if (this_node->type == ACPI_TYPE_LOCAL_ALIAS) { 626 if (!this_node->object) { 627 return_ACPI_STATUS(AE_NOT_EXIST); 628 } 629 630 if (acpi_ns_opens_scope 631 (((struct acpi_namespace_node *) 632 this_node->object)->type)) { 633 this_node = 634 (struct acpi_namespace_node *) 635 this_node->object; 636 } 637 } 638 } 639 640 /* Special handling for the last segment (num_segments == 0) */ 641 642 else { 643 /* 644 * Sanity typecheck of the target object: 645 * 646 * If 1) This is the last segment (num_segments == 0) 647 * 2) And we are looking for a specific type 648 * (Not checking for TYPE_ANY) 649 * 3) Which is not an alias 650 * 4) Which is not a local type (TYPE_SCOPE) 651 * 5) And the type of target object is known (not TYPE_ANY) 652 * 6) And target object does not match what we are looking for 653 * 654 * Then we have a type mismatch. Just warn and ignore it. 655 */ 656 if ((type_to_check_for != ACPI_TYPE_ANY) && 657 (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) && 658 (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS) 659 && (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE) 660 && (this_node->type != ACPI_TYPE_ANY) 661 && (this_node->type != type_to_check_for)) { 662 663 /* Complain about a type mismatch */ 664 665 ACPI_WARNING((AE_INFO, 666 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)", 667 ACPI_CAST_PTR(char, &simple_name), 668 acpi_ut_get_type_name(this_node-> 669 type), 670 acpi_ut_get_type_name 671 (type_to_check_for))); 672 } 673 674 /* 675 * If this is the last name segment and we are not looking for a 676 * specific type, but the type of found object is known, use that 677 * type to (later) see if it opens a scope. 678 */ 679 if (type == ACPI_TYPE_ANY) { 680 type = this_node->type; 681 } 682 } 683 684 /* Point to next name segment and make this node current */ 685 686 path += ACPI_NAME_SIZE; 687 current_node = this_node; 688 } 689 690 /* Always check if we need to open a new scope */ 691 692 if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) { 693 /* 694 * If entry is a type which opens a scope, push the new scope on the 695 * scope stack. 696 */ 697 if (acpi_ns_opens_scope(type)) { 698 status = 699 acpi_ds_scope_stack_push(this_node, type, 700 walk_state); 701 if (ACPI_FAILURE(status)) { 702 return_ACPI_STATUS(status); 703 } 704 } 705 } 706 #ifdef ACPI_EXEC_APP 707 if (flags & ACPI_NS_EARLY_INIT) { 708 this_node->flags |= ANOBJ_NODE_EARLY_INIT; 709 } 710 #endif 711 712 *return_node = this_node; 713 return_ACPI_STATUS(AE_OK); 714 } 715