1 /******************************************************************************* 2 * 3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace 4 * 5 ******************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2016, 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 "amlcode.h" 47 #include "acnamesp.h" 48 #include "acdispat.h" 49 50 #define _COMPONENT ACPI_NAMESPACE 51 ACPI_MODULE_NAME("nsaccess") 52 53 /******************************************************************************* 54 * 55 * FUNCTION: acpi_ns_root_initialize 56 * 57 * PARAMETERS: None 58 * 59 * RETURN: Status 60 * 61 * DESCRIPTION: Allocate and initialize the default root named objects 62 * 63 * MUTEX: Locks namespace for entire execution 64 * 65 ******************************************************************************/ 66 acpi_status acpi_ns_root_initialize(void) 67 { 68 acpi_status status; 69 const struct acpi_predefined_names *init_val = NULL; 70 struct acpi_namespace_node *new_node; 71 union acpi_operand_object *obj_desc; 72 acpi_string val = NULL; 73 74 ACPI_FUNCTION_TRACE(ns_root_initialize); 75 76 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE); 77 if (ACPI_FAILURE(status)) { 78 return_ACPI_STATUS(status); 79 } 80 81 /* 82 * The global root ptr is initially NULL, so a non-NULL value indicates 83 * that acpi_ns_root_initialize() has already been called; just return. 84 */ 85 if (acpi_gbl_root_node) { 86 status = AE_OK; 87 goto unlock_and_exit; 88 } 89 90 /* 91 * Tell the rest of the subsystem that the root is initialized 92 * (This is OK because the namespace is locked) 93 */ 94 acpi_gbl_root_node = &acpi_gbl_root_node_struct; 95 96 /* Enter the pre-defined names in the name table */ 97 98 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 99 "Entering predefined entries into namespace\n")); 100 101 for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) { 102 103 /* _OSI is optional for now, will be permanent later */ 104 105 if (!strcmp(init_val->name, "_OSI") 106 && !acpi_gbl_create_osi_method) { 107 continue; 108 } 109 110 status = 111 acpi_ns_lookup(NULL, ACPI_CAST_PTR(char, init_val->name), 112 init_val->type, ACPI_IMODE_LOAD_PASS2, 113 ACPI_NS_NO_UPSEARCH, NULL, &new_node); 114 if (ACPI_FAILURE(status)) { 115 ACPI_EXCEPTION((AE_INFO, status, 116 "Could not create predefined name %s", 117 init_val->name)); 118 continue; 119 } 120 121 /* 122 * Name entered successfully. If entry in pre_defined_names[] specifies 123 * an initial value, create the initial value. 124 */ 125 if (init_val->val) { 126 status = acpi_os_predefined_override(init_val, &val); 127 if (ACPI_FAILURE(status)) { 128 ACPI_ERROR((AE_INFO, 129 "Could not override predefined %s", 130 init_val->name)); 131 } 132 133 if (!val) { 134 val = init_val->val; 135 } 136 137 /* 138 * Entry requests an initial value, allocate a 139 * descriptor for it. 140 */ 141 obj_desc = 142 acpi_ut_create_internal_object(init_val->type); 143 if (!obj_desc) { 144 status = AE_NO_MEMORY; 145 goto unlock_and_exit; 146 } 147 148 /* 149 * Convert value string from table entry to 150 * internal representation. Only types actually 151 * used for initial values are implemented here. 152 */ 153 switch (init_val->type) { 154 case ACPI_TYPE_METHOD: 155 156 obj_desc->method.param_count = 157 (u8) ACPI_TO_INTEGER(val); 158 obj_desc->common.flags |= AOPOBJ_DATA_VALID; 159 160 #if defined (ACPI_ASL_COMPILER) 161 162 /* Save the parameter count for the iASL compiler */ 163 164 new_node->value = obj_desc->method.param_count; 165 #else 166 /* Mark this as a very SPECIAL method */ 167 168 obj_desc->method.info_flags = 169 ACPI_METHOD_INTERNAL_ONLY; 170 obj_desc->method.dispatch.implementation = 171 acpi_ut_osi_implementation; 172 #endif 173 break; 174 175 case ACPI_TYPE_INTEGER: 176 177 obj_desc->integer.value = ACPI_TO_INTEGER(val); 178 break; 179 180 case ACPI_TYPE_STRING: 181 182 /* Build an object around the static string */ 183 184 obj_desc->string.length = (u32)strlen(val); 185 obj_desc->string.pointer = val; 186 obj_desc->common.flags |= AOPOBJ_STATIC_POINTER; 187 break; 188 189 case ACPI_TYPE_MUTEX: 190 191 obj_desc->mutex.node = new_node; 192 obj_desc->mutex.sync_level = 193 (u8) (ACPI_TO_INTEGER(val) - 1); 194 195 /* Create a mutex */ 196 197 status = 198 acpi_os_create_mutex(&obj_desc->mutex. 199 os_mutex); 200 if (ACPI_FAILURE(status)) { 201 acpi_ut_remove_reference(obj_desc); 202 goto unlock_and_exit; 203 } 204 205 /* Special case for ACPI Global Lock */ 206 207 if (strcmp(init_val->name, "_GL_") == 0) { 208 acpi_gbl_global_lock_mutex = obj_desc; 209 210 /* Create additional counting semaphore for global lock */ 211 212 status = 213 acpi_os_create_semaphore(1, 0, 214 &acpi_gbl_global_lock_semaphore); 215 if (ACPI_FAILURE(status)) { 216 acpi_ut_remove_reference 217 (obj_desc); 218 goto unlock_and_exit; 219 } 220 } 221 break; 222 223 default: 224 225 ACPI_ERROR((AE_INFO, 226 "Unsupported initial type value 0x%X", 227 init_val->type)); 228 acpi_ut_remove_reference(obj_desc); 229 obj_desc = NULL; 230 continue; 231 } 232 233 /* Store pointer to value descriptor in the Node */ 234 235 status = acpi_ns_attach_object(new_node, obj_desc, 236 obj_desc->common.type); 237 238 /* Remove local reference to the object */ 239 240 acpi_ut_remove_reference(obj_desc); 241 } 242 } 243 244 unlock_and_exit: 245 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE); 246 247 /* Save a handle to "_GPE", it is always present */ 248 249 if (ACPI_SUCCESS(status)) { 250 status = acpi_ns_get_node(NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH, 251 &acpi_gbl_fadt_gpe_device); 252 } 253 254 return_ACPI_STATUS(status); 255 } 256 257 /******************************************************************************* 258 * 259 * FUNCTION: acpi_ns_lookup 260 * 261 * PARAMETERS: scope_info - Current scope info block 262 * pathname - Search pathname, in internal format 263 * (as represented in the AML stream) 264 * type - Type associated with name 265 * interpreter_mode - IMODE_LOAD_PASS2 => add name if not found 266 * flags - Flags describing the search restrictions 267 * walk_state - Current state of the walk 268 * return_node - Where the Node is placed (if found 269 * or created successfully) 270 * 271 * RETURN: Status 272 * 273 * DESCRIPTION: Find or enter the passed name in the name space. 274 * Log an error if name not found in Exec mode. 275 * 276 * MUTEX: Assumes namespace is locked. 277 * 278 ******************************************************************************/ 279 280 acpi_status 281 acpi_ns_lookup(union acpi_generic_state *scope_info, 282 char *pathname, 283 acpi_object_type type, 284 acpi_interpreter_mode interpreter_mode, 285 u32 flags, 286 struct acpi_walk_state *walk_state, 287 struct acpi_namespace_node **return_node) 288 { 289 acpi_status status; 290 char *path = pathname; 291 struct acpi_namespace_node *prefix_node; 292 struct acpi_namespace_node *current_node = NULL; 293 struct acpi_namespace_node *this_node = NULL; 294 u32 num_segments; 295 u32 num_carats; 296 acpi_name simple_name; 297 acpi_object_type type_to_check_for; 298 acpi_object_type this_search_type; 299 u32 search_parent_flag = ACPI_NS_SEARCH_PARENT; 300 u32 local_flags; 301 302 ACPI_FUNCTION_TRACE(ns_lookup); 303 304 if (!return_node) { 305 return_ACPI_STATUS(AE_BAD_PARAMETER); 306 } 307 308 local_flags = flags & 309 ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND | 310 ACPI_NS_SEARCH_PARENT); 311 *return_node = ACPI_ENTRY_NOT_FOUND; 312 acpi_gbl_ns_lookup_count++; 313 314 if (!acpi_gbl_root_node) { 315 return_ACPI_STATUS(AE_NO_NAMESPACE); 316 } 317 318 /* Get the prefix scope. A null scope means use the root scope */ 319 320 if ((!scope_info) || (!scope_info->scope.node)) { 321 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 322 "Null scope prefix, using root node (%p)\n", 323 acpi_gbl_root_node)); 324 325 prefix_node = acpi_gbl_root_node; 326 } else { 327 prefix_node = scope_info->scope.node; 328 if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) != 329 ACPI_DESC_TYPE_NAMED) { 330 ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]", 331 prefix_node, 332 acpi_ut_get_descriptor_name(prefix_node))); 333 return_ACPI_STATUS(AE_AML_INTERNAL); 334 } 335 336 if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) { 337 /* 338 * This node might not be a actual "scope" node (such as a 339 * Device/Method, etc.) It could be a Package or other object 340 * node. Backup up the tree to find the containing scope node. 341 */ 342 while (!acpi_ns_opens_scope(prefix_node->type) && 343 prefix_node->type != ACPI_TYPE_ANY) { 344 prefix_node = prefix_node->parent; 345 } 346 } 347 } 348 349 /* Save type. TBD: may be no longer necessary */ 350 351 type_to_check_for = type; 352 353 /* 354 * Begin examination of the actual pathname 355 */ 356 if (!pathname) { 357 358 /* A Null name_path is allowed and refers to the root */ 359 360 num_segments = 0; 361 this_node = acpi_gbl_root_node; 362 path = ""; 363 364 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 365 "Null Pathname (Zero segments), Flags=%X\n", 366 flags)); 367 } else { 368 /* 369 * Name pointer is valid (and must be in internal name format) 370 * 371 * Check for scope prefixes: 372 * 373 * As represented in the AML stream, a namepath consists of an 374 * optional scope prefix followed by a name segment part. 375 * 376 * If present, the scope prefix is either a Root Prefix (in 377 * which case the name is fully qualified), or one or more 378 * Parent Prefixes (in which case the name's scope is relative 379 * to the current scope). 380 */ 381 if (*path == (u8) AML_ROOT_PREFIX) { 382 383 /* Pathname is fully qualified, start from the root */ 384 385 this_node = acpi_gbl_root_node; 386 search_parent_flag = ACPI_NS_NO_UPSEARCH; 387 388 /* Point to name segment part */ 389 390 path++; 391 392 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 393 "Path is absolute from root [%p]\n", 394 this_node)); 395 } else { 396 /* Pathname is relative to current scope, start there */ 397 398 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 399 "Searching relative to prefix scope [%4.4s] (%p)\n", 400 acpi_ut_get_node_name(prefix_node), 401 prefix_node)); 402 403 /* 404 * Handle multiple Parent Prefixes (carat) by just getting 405 * the parent node for each prefix instance. 406 */ 407 this_node = prefix_node; 408 num_carats = 0; 409 while (*path == (u8) AML_PARENT_PREFIX) { 410 411 /* Name is fully qualified, no search rules apply */ 412 413 search_parent_flag = ACPI_NS_NO_UPSEARCH; 414 415 /* 416 * Point past this prefix to the name segment 417 * part or the next Parent Prefix 418 */ 419 path++; 420 421 /* Backup to the parent node */ 422 423 num_carats++; 424 this_node = this_node->parent; 425 if (!this_node) { 426 427 /* Current scope has no parent scope */ 428 429 ACPI_ERROR((AE_INFO, 430 "%s: Path has too many parent prefixes (^) " 431 "- reached beyond root node", 432 pathname)); 433 return_ACPI_STATUS(AE_NOT_FOUND); 434 } 435 } 436 437 if (search_parent_flag == ACPI_NS_NO_UPSEARCH) { 438 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 439 "Search scope is [%4.4s], path has %u carat(s)\n", 440 acpi_ut_get_node_name 441 (this_node), num_carats)); 442 } 443 } 444 445 /* 446 * Determine the number of ACPI name segments in this pathname. 447 * 448 * The segment part consists of either: 449 * - A Null name segment (0) 450 * - A dual_name_prefix followed by two 4-byte name segments 451 * - A multi_name_prefix followed by a byte indicating the 452 * number of segments and the segments themselves. 453 * - A single 4-byte name segment 454 * 455 * Examine the name prefix opcode, if any, to determine the number of 456 * segments. 457 */ 458 switch (*path) { 459 case 0: 460 /* 461 * Null name after a root or parent prefixes. We already 462 * have the correct target node and there are no name segments. 463 */ 464 num_segments = 0; 465 type = this_node->type; 466 467 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 468 "Prefix-only Pathname (Zero name segments), Flags=%X\n", 469 flags)); 470 break; 471 472 case AML_DUAL_NAME_PREFIX: 473 474 /* More than one name_seg, search rules do not apply */ 475 476 search_parent_flag = ACPI_NS_NO_UPSEARCH; 477 478 /* Two segments, point to first name segment */ 479 480 num_segments = 2; 481 path++; 482 483 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 484 "Dual Pathname (2 segments, Flags=%X)\n", 485 flags)); 486 break; 487 488 case AML_MULTI_NAME_PREFIX_OP: 489 490 /* More than one name_seg, search rules do not apply */ 491 492 search_parent_flag = ACPI_NS_NO_UPSEARCH; 493 494 /* Extract segment count, point to first name segment */ 495 496 path++; 497 num_segments = (u32) (u8) * path; 498 path++; 499 500 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 501 "Multi Pathname (%u Segments, Flags=%X)\n", 502 num_segments, flags)); 503 break; 504 505 default: 506 /* 507 * Not a Null name, no Dual or Multi prefix, hence there is 508 * only one name segment and Pathname is already pointing to it. 509 */ 510 num_segments = 1; 511 512 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 513 "Simple Pathname (1 segment, Flags=%X)\n", 514 flags)); 515 break; 516 } 517 518 ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path)); 519 } 520 521 /* 522 * Search namespace for each segment of the name. Loop through and 523 * verify (or add to the namespace) each name segment. 524 * 525 * The object type is significant only at the last name 526 * segment. (We don't care about the types along the path, only 527 * the type of the final target object.) 528 */ 529 this_search_type = ACPI_TYPE_ANY; 530 current_node = this_node; 531 while (num_segments && current_node) { 532 num_segments--; 533 if (!num_segments) { 534 535 /* This is the last segment, enable typechecking */ 536 537 this_search_type = type; 538 539 /* 540 * Only allow automatic parent search (search rules) if the caller 541 * requested it AND we have a single, non-fully-qualified name_seg 542 */ 543 if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) && 544 (flags & ACPI_NS_SEARCH_PARENT)) { 545 local_flags |= ACPI_NS_SEARCH_PARENT; 546 } 547 548 /* Set error flag according to caller */ 549 550 if (flags & ACPI_NS_ERROR_IF_FOUND) { 551 local_flags |= ACPI_NS_ERROR_IF_FOUND; 552 } 553 554 /* Set override flag according to caller */ 555 556 if (flags & ACPI_NS_OVERRIDE_IF_FOUND) { 557 local_flags |= ACPI_NS_OVERRIDE_IF_FOUND; 558 } 559 } 560 561 /* Extract one ACPI name from the front of the pathname */ 562 563 ACPI_MOVE_32_TO_32(&simple_name, path); 564 565 /* Try to find the single (4 character) ACPI name */ 566 567 status = 568 acpi_ns_search_and_enter(simple_name, walk_state, 569 current_node, interpreter_mode, 570 this_search_type, local_flags, 571 &this_node); 572 if (ACPI_FAILURE(status)) { 573 if (status == AE_NOT_FOUND) { 574 575 /* Name not found in ACPI namespace */ 576 577 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, 578 "Name [%4.4s] not found in scope [%4.4s] %p\n", 579 (char *)&simple_name, 580 (char *)¤t_node->name, 581 current_node)); 582 } 583 584 *return_node = this_node; 585 return_ACPI_STATUS(status); 586 } 587 588 /* More segments to follow? */ 589 590 if (num_segments > 0) { 591 /* 592 * If we have an alias to an object that opens a scope (such as a 593 * device or processor), we need to dereference the alias here so 594 * that we can access any children of the original node (via the 595 * remaining segments). 596 */ 597 if (this_node->type == ACPI_TYPE_LOCAL_ALIAS) { 598 if (!this_node->object) { 599 return_ACPI_STATUS(AE_NOT_EXIST); 600 } 601 602 if (acpi_ns_opens_scope 603 (((struct acpi_namespace_node *) 604 this_node->object)->type)) { 605 this_node = 606 (struct acpi_namespace_node *) 607 this_node->object; 608 } 609 } 610 } 611 612 /* Special handling for the last segment (num_segments == 0) */ 613 614 else { 615 /* 616 * Sanity typecheck of the target object: 617 * 618 * If 1) This is the last segment (num_segments == 0) 619 * 2) And we are looking for a specific type 620 * (Not checking for TYPE_ANY) 621 * 3) Which is not an alias 622 * 4) Which is not a local type (TYPE_SCOPE) 623 * 5) And the type of target object is known (not TYPE_ANY) 624 * 6) And target object does not match what we are looking for 625 * 626 * Then we have a type mismatch. Just warn and ignore it. 627 */ 628 if ((type_to_check_for != ACPI_TYPE_ANY) && 629 (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) && 630 (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS) 631 && (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE) 632 && (this_node->type != ACPI_TYPE_ANY) 633 && (this_node->type != type_to_check_for)) { 634 635 /* Complain about a type mismatch */ 636 637 ACPI_WARNING((AE_INFO, 638 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)", 639 ACPI_CAST_PTR(char, &simple_name), 640 acpi_ut_get_type_name(this_node-> 641 type), 642 acpi_ut_get_type_name 643 (type_to_check_for))); 644 } 645 646 /* 647 * If this is the last name segment and we are not looking for a 648 * specific type, but the type of found object is known, use that 649 * type to (later) see if it opens a scope. 650 */ 651 if (type == ACPI_TYPE_ANY) { 652 type = this_node->type; 653 } 654 } 655 656 /* Point to next name segment and make this node current */ 657 658 path += ACPI_NAME_SIZE; 659 current_node = this_node; 660 } 661 662 /* Always check if we need to open a new scope */ 663 664 if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) { 665 /* 666 * If entry is a type which opens a scope, push the new scope on the 667 * scope stack. 668 */ 669 if (acpi_ns_opens_scope(type)) { 670 status = 671 acpi_ds_scope_stack_push(this_node, type, 672 walk_state); 673 if (ACPI_FAILURE(status)) { 674 return_ACPI_STATUS(status); 675 } 676 } 677 } 678 679 *return_node = this_node; 680 return_ACPI_STATUS(AE_OK); 681 } 682