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; 270 271 ACPI_FUNCTION_TRACE(ns_lookup); 272 273 if (!return_node) { 274 return_ACPI_STATUS(AE_BAD_PARAMETER); 275 } 276 277 local_flags = flags & 278 ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND | 279 ACPI_NS_SEARCH_PARENT); 280 *return_node = ACPI_ENTRY_NOT_FOUND; 281 acpi_gbl_ns_lookup_count++; 282 283 if (!acpi_gbl_root_node) { 284 return_ACPI_STATUS(AE_NO_NAMESPACE); 285 } 286 287 /* Get the prefix scope. A null scope means use the root scope */ 288 289 if ((!scope_info) || (!scope_info->scope.node)) { 290 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 291 "Null scope prefix, using root node (%p)\n", 292 acpi_gbl_root_node)); 293 294 prefix_node = acpi_gbl_root_node; 295 } else { 296 prefix_node = scope_info->scope.node; 297 if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) != 298 ACPI_DESC_TYPE_NAMED) { 299 ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]", 300 prefix_node, 301 acpi_ut_get_descriptor_name(prefix_node))); 302 return_ACPI_STATUS(AE_AML_INTERNAL); 303 } 304 305 if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) { 306 /* 307 * This node might not be a actual "scope" node (such as a 308 * Device/Method, etc.) It could be a Package or other object 309 * node. Backup up the tree to find the containing scope node. 310 */ 311 while (!acpi_ns_opens_scope(prefix_node->type) && 312 prefix_node->type != ACPI_TYPE_ANY) { 313 prefix_node = prefix_node->parent; 314 } 315 } 316 } 317 318 /* Save type. TBD: may be no longer necessary */ 319 320 type_to_check_for = type; 321 322 /* 323 * Begin examination of the actual pathname 324 */ 325 if (!pathname) { 326 327 /* A Null name_path is allowed and refers to the root */ 328 329 num_segments = 0; 330 this_node = acpi_gbl_root_node; 331 path = ""; 332 333 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 334 "Null Pathname (Zero segments), Flags=%X\n", 335 flags)); 336 } else { 337 /* 338 * Name pointer is valid (and must be in internal name format) 339 * 340 * Check for scope prefixes: 341 * 342 * As represented in the AML stream, a namepath consists of an 343 * optional scope prefix followed by a name segment part. 344 * 345 * If present, the scope prefix is either a Root Prefix (in 346 * which case the name is fully qualified), or one or more 347 * Parent Prefixes (in which case the name's scope is relative 348 * to the current scope). 349 */ 350 if (*path == (u8) AML_ROOT_PREFIX) { 351 352 /* Pathname is fully qualified, start from the root */ 353 354 this_node = acpi_gbl_root_node; 355 search_parent_flag = ACPI_NS_NO_UPSEARCH; 356 357 /* Point to name segment part */ 358 359 path++; 360 361 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 362 "Path is absolute from root [%p]\n", 363 this_node)); 364 } else { 365 /* Pathname is relative to current scope, start there */ 366 367 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 368 "Searching relative to prefix scope [%4.4s] (%p)\n", 369 acpi_ut_get_node_name(prefix_node), 370 prefix_node)); 371 372 /* 373 * Handle multiple Parent Prefixes (carat) by just getting 374 * the parent node for each prefix instance. 375 */ 376 this_node = prefix_node; 377 num_carats = 0; 378 while (*path == (u8) AML_PARENT_PREFIX) { 379 380 /* Name is fully qualified, no search rules apply */ 381 382 search_parent_flag = ACPI_NS_NO_UPSEARCH; 383 384 /* 385 * Point past this prefix to the name segment 386 * part or the next Parent Prefix 387 */ 388 path++; 389 390 /* Backup to the parent node */ 391 392 num_carats++; 393 this_node = this_node->parent; 394 if (!this_node) { 395 /* 396 * Current scope has no parent scope. Externalize 397 * the internal path for error message. 398 */ 399 status = 400 acpi_ns_externalize_name 401 (ACPI_UINT32_MAX, pathname, NULL, 402 &external_path); 403 if (ACPI_SUCCESS(status)) { 404 ACPI_ERROR((AE_INFO, 405 "%s: Path has too many parent prefixes (^)", 406 external_path)); 407 408 ACPI_FREE(external_path); 409 } 410 411 return_ACPI_STATUS(AE_NOT_FOUND); 412 } 413 } 414 415 if (search_parent_flag == ACPI_NS_NO_UPSEARCH) { 416 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 417 "Search scope is [%4.4s], path has %u carat(s)\n", 418 acpi_ut_get_node_name 419 (this_node), num_carats)); 420 } 421 } 422 423 /* 424 * Determine the number of ACPI name segments in this pathname. 425 * 426 * The segment part consists of either: 427 * - A Null name segment (0) 428 * - A dual_name_prefix followed by two 4-byte name segments 429 * - A multi_name_prefix followed by a byte indicating the 430 * number of segments and the segments themselves. 431 * - A single 4-byte name segment 432 * 433 * Examine the name prefix opcode, if any, to determine the number of 434 * segments. 435 */ 436 switch (*path) { 437 case 0: 438 /* 439 * Null name after a root or parent prefixes. We already 440 * have the correct target node and there are no name segments. 441 */ 442 num_segments = 0; 443 type = this_node->type; 444 445 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 446 "Prefix-only Pathname (Zero name segments), Flags=%X\n", 447 flags)); 448 break; 449 450 case AML_DUAL_NAME_PREFIX: 451 452 /* More than one name_seg, search rules do not apply */ 453 454 search_parent_flag = ACPI_NS_NO_UPSEARCH; 455 456 /* Two segments, point to first name segment */ 457 458 num_segments = 2; 459 path++; 460 461 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 462 "Dual Pathname (2 segments, Flags=%X)\n", 463 flags)); 464 break; 465 466 case AML_MULTI_NAME_PREFIX: 467 468 /* More than one name_seg, search rules do not apply */ 469 470 search_parent_flag = ACPI_NS_NO_UPSEARCH; 471 472 /* Extract segment count, point to first name segment */ 473 474 path++; 475 num_segments = (u32) (u8) * path; 476 path++; 477 478 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 479 "Multi Pathname (%u Segments, Flags=%X)\n", 480 num_segments, flags)); 481 break; 482 483 default: 484 /* 485 * Not a Null name, no Dual or Multi prefix, hence there is 486 * only one name segment and Pathname is already pointing to it. 487 */ 488 num_segments = 1; 489 490 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 491 "Simple Pathname (1 segment, Flags=%X)\n", 492 flags)); 493 break; 494 } 495 496 ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path)); 497 } 498 499 /* 500 * Search namespace for each segment of the name. Loop through and 501 * verify (or add to the namespace) each name segment. 502 * 503 * The object type is significant only at the last name 504 * segment. (We don't care about the types along the path, only 505 * the type of the final target object.) 506 */ 507 this_search_type = ACPI_TYPE_ANY; 508 current_node = this_node; 509 while (num_segments && current_node) { 510 num_segments--; 511 if (!num_segments) { 512 513 /* This is the last segment, enable typechecking */ 514 515 this_search_type = type; 516 517 /* 518 * Only allow automatic parent search (search rules) if the caller 519 * requested it AND we have a single, non-fully-qualified name_seg 520 */ 521 if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) && 522 (flags & ACPI_NS_SEARCH_PARENT)) { 523 local_flags |= ACPI_NS_SEARCH_PARENT; 524 } 525 526 /* Set error flag according to caller */ 527 528 if (flags & ACPI_NS_ERROR_IF_FOUND) { 529 local_flags |= ACPI_NS_ERROR_IF_FOUND; 530 } 531 532 /* Set override flag according to caller */ 533 534 if (flags & ACPI_NS_OVERRIDE_IF_FOUND) { 535 local_flags |= ACPI_NS_OVERRIDE_IF_FOUND; 536 } 537 } 538 539 /* Extract one ACPI name from the front of the pathname */ 540 541 ACPI_MOVE_32_TO_32(&simple_name, path); 542 543 /* Try to find the single (4 character) ACPI name */ 544 545 status = 546 acpi_ns_search_and_enter(simple_name, walk_state, 547 current_node, interpreter_mode, 548 this_search_type, local_flags, 549 &this_node); 550 if (ACPI_FAILURE(status)) { 551 if (status == AE_NOT_FOUND) { 552 553 /* Name not found in ACPI namespace */ 554 555 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 556 "Name [%4.4s] not found in scope [%4.4s] %p\n", 557 (char *)&simple_name, 558 (char *)¤t_node->name, 559 current_node)); 560 } 561 #ifdef ACPI_ASL_COMPILER 562 /* 563 * If this ACPI name already exists within the namespace as an 564 * external declaration, then mark the external as a conflicting 565 * declaration and proceed to process the current node as if it did 566 * not exist in the namespace. If this node is not processed as 567 * normal, then it could cause improper namespace resolution 568 * by failing to open a new scope. 569 */ 570 if (acpi_gbl_disasm_flag && 571 (status == AE_ALREADY_EXISTS) && 572 ((this_node->flags & ANOBJ_IS_EXTERNAL) || 573 (walk_state 574 && walk_state->opcode == AML_EXTERNAL_OP))) { 575 this_node->flags &= ~ANOBJ_IS_EXTERNAL; 576 this_node->type = (u8)this_search_type; 577 if (walk_state->opcode != AML_EXTERNAL_OP) { 578 acpi_dm_mark_external_conflict 579 (this_node); 580 } 581 break; 582 } 583 #endif 584 585 *return_node = this_node; 586 return_ACPI_STATUS(status); 587 } 588 589 /* More segments to follow? */ 590 591 if (num_segments > 0) { 592 /* 593 * If we have an alias to an object that opens a scope (such as a 594 * device or processor), we need to dereference the alias here so 595 * that we can access any children of the original node (via the 596 * remaining segments). 597 */ 598 if (this_node->type == ACPI_TYPE_LOCAL_ALIAS) { 599 if (!this_node->object) { 600 return_ACPI_STATUS(AE_NOT_EXIST); 601 } 602 603 if (acpi_ns_opens_scope 604 (((struct acpi_namespace_node *) 605 this_node->object)->type)) { 606 this_node = 607 (struct acpi_namespace_node *) 608 this_node->object; 609 } 610 } 611 } 612 613 /* Special handling for the last segment (num_segments == 0) */ 614 615 else { 616 #ifdef ACPI_ASL_COMPILER 617 if (!acpi_gbl_disasm_flag 618 && (this_node->flags & ANOBJ_IS_EXTERNAL)) { 619 this_node->flags &= ~IMPLICIT_EXTERNAL; 620 } 621 #endif 622 623 /* 624 * Sanity typecheck of the target object: 625 * 626 * If 1) This is the last segment (num_segments == 0) 627 * 2) And we are looking for a specific type 628 * (Not checking for TYPE_ANY) 629 * 3) Which is not an alias 630 * 4) Which is not a local type (TYPE_SCOPE) 631 * 5) And the type of target object is known (not TYPE_ANY) 632 * 6) And target object does not match what we are looking for 633 * 634 * Then we have a type mismatch. Just warn and ignore it. 635 */ 636 if ((type_to_check_for != ACPI_TYPE_ANY) && 637 (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) && 638 (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS) 639 && (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE) 640 && (this_node->type != ACPI_TYPE_ANY) 641 && (this_node->type != type_to_check_for)) { 642 643 /* Complain about a type mismatch */ 644 645 ACPI_WARNING((AE_INFO, 646 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)", 647 ACPI_CAST_PTR(char, &simple_name), 648 acpi_ut_get_type_name(this_node-> 649 type), 650 acpi_ut_get_type_name 651 (type_to_check_for))); 652 } 653 654 /* 655 * If this is the last name segment and we are not looking for a 656 * specific type, but the type of found object is known, use that 657 * type to (later) see if it opens a scope. 658 */ 659 if (type == ACPI_TYPE_ANY) { 660 type = this_node->type; 661 } 662 } 663 664 /* Point to next name segment and make this node current */ 665 666 path += ACPI_NAME_SIZE; 667 current_node = this_node; 668 } 669 670 /* Always check if we need to open a new scope */ 671 672 if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) { 673 /* 674 * If entry is a type which opens a scope, push the new scope on the 675 * scope stack. 676 */ 677 if (acpi_ns_opens_scope(type)) { 678 status = 679 acpi_ds_scope_stack_push(this_node, type, 680 walk_state); 681 if (ACPI_FAILURE(status)) { 682 return_ACPI_STATUS(status); 683 } 684 } 685 } 686 687 *return_node = this_node; 688 return_ACPI_STATUS(AE_OK); 689 } 690