1 /******************************************************************************* 2 * 3 * Module Name: nssearch - Namespace search 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.h" 45 #include "accommon.h" 46 #include "acnamesp.h" 47 48 #ifdef ACPI_ASL_COMPILER 49 #include "amlcode.h" 50 #endif 51 52 #define _COMPONENT ACPI_NAMESPACE 53 ACPI_MODULE_NAME ("nssearch") 54 55 /* Local prototypes */ 56 57 static ACPI_STATUS 58 AcpiNsSearchParentTree ( 59 UINT32 TargetName, 60 ACPI_NAMESPACE_NODE *Node, 61 ACPI_OBJECT_TYPE Type, 62 ACPI_NAMESPACE_NODE **ReturnNode); 63 64 65 /******************************************************************************* 66 * 67 * FUNCTION: AcpiNsSearchOneScope 68 * 69 * PARAMETERS: TargetName - Ascii ACPI name to search for 70 * ParentNode - Starting node where search will begin 71 * Type - Object type to match 72 * ReturnNode - Where the matched Named obj is returned 73 * 74 * RETURN: Status 75 * 76 * DESCRIPTION: Search a single level of the namespace. Performs a 77 * simple search of the specified level, and does not add 78 * entries or search parents. 79 * 80 * 81 * Named object lists are built (and subsequently dumped) in the 82 * order in which the names are encountered during the namespace load; 83 * 84 * All namespace searching is linear in this implementation, but 85 * could be easily modified to support any improved search 86 * algorithm. However, the linear search was chosen for simplicity 87 * and because the trees are small and the other interpreter 88 * execution overhead is relatively high. 89 * 90 * Note: CPU execution analysis has shown that the AML interpreter spends 91 * a very small percentage of its time searching the namespace. Therefore, 92 * the linear search seems to be sufficient, as there would seem to be 93 * little value in improving the search. 94 * 95 ******************************************************************************/ 96 97 ACPI_STATUS 98 AcpiNsSearchOneScope ( 99 UINT32 TargetName, 100 ACPI_NAMESPACE_NODE *ParentNode, 101 ACPI_OBJECT_TYPE Type, 102 ACPI_NAMESPACE_NODE **ReturnNode) 103 { 104 ACPI_NAMESPACE_NODE *Node; 105 106 107 ACPI_FUNCTION_TRACE (NsSearchOneScope); 108 109 110 #ifdef ACPI_DEBUG_OUTPUT 111 if (ACPI_LV_NAMES & AcpiDbgLevel) 112 { 113 char *ScopeName; 114 115 ScopeName = AcpiNsGetNormalizedPathname (ParentNode, TRUE); 116 if (ScopeName) 117 { 118 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 119 "Searching %s (%p) For [%4.4s] (%s)\n", 120 ScopeName, ParentNode, ACPI_CAST_PTR (char, &TargetName), 121 AcpiUtGetTypeName (Type))); 122 123 ACPI_FREE (ScopeName); 124 } 125 } 126 #endif 127 128 /* 129 * Search for name at this namespace level, which is to say that we 130 * must search for the name among the children of this object 131 */ 132 Node = ParentNode->Child; 133 while (Node) 134 { 135 /* Check for match against the name */ 136 137 if (Node->Name.Integer == TargetName) 138 { 139 /* Resolve a control method alias if any */ 140 141 if (AcpiNsGetType (Node) == ACPI_TYPE_LOCAL_METHOD_ALIAS) 142 { 143 Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, Node->Object); 144 } 145 146 /* Found matching entry */ 147 148 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 149 "Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n", 150 ACPI_CAST_PTR (char, &TargetName), 151 AcpiUtGetTypeName (Node->Type), 152 Node, AcpiUtGetNodeName (ParentNode), ParentNode)); 153 154 *ReturnNode = Node; 155 return_ACPI_STATUS (AE_OK); 156 } 157 158 /* Didn't match name, move on to the next peer object */ 159 160 Node = Node->Peer; 161 } 162 163 /* Searched entire namespace level, not found */ 164 165 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 166 "Name [%4.4s] (%s) not found in search in scope [%4.4s] " 167 "%p first child %p\n", 168 ACPI_CAST_PTR (char, &TargetName), AcpiUtGetTypeName (Type), 169 AcpiUtGetNodeName (ParentNode), ParentNode, ParentNode->Child)); 170 171 return_ACPI_STATUS (AE_NOT_FOUND); 172 } 173 174 175 /******************************************************************************* 176 * 177 * FUNCTION: AcpiNsSearchParentTree 178 * 179 * PARAMETERS: TargetName - Ascii ACPI name to search for 180 * Node - Starting node where search will begin 181 * Type - Object type to match 182 * ReturnNode - Where the matched Node is returned 183 * 184 * RETURN: Status 185 * 186 * DESCRIPTION: Called when a name has not been found in the current namespace 187 * level. Before adding it or giving up, ACPI scope rules require 188 * searching enclosing scopes in cases identified by AcpiNsLocal(). 189 * 190 * "A name is located by finding the matching name in the current 191 * name space, and then in the parent name space. If the parent 192 * name space does not contain the name, the search continues 193 * recursively until either the name is found or the name space 194 * does not have a parent (the root of the name space). This 195 * indicates that the name is not found" (From ACPI Specification, 196 * section 5.3) 197 * 198 ******************************************************************************/ 199 200 static ACPI_STATUS 201 AcpiNsSearchParentTree ( 202 UINT32 TargetName, 203 ACPI_NAMESPACE_NODE *Node, 204 ACPI_OBJECT_TYPE Type, 205 ACPI_NAMESPACE_NODE **ReturnNode) 206 { 207 ACPI_STATUS Status; 208 ACPI_NAMESPACE_NODE *ParentNode; 209 210 211 ACPI_FUNCTION_TRACE (NsSearchParentTree); 212 213 214 ParentNode = Node->Parent; 215 216 /* 217 * If there is no parent (i.e., we are at the root) or type is "local", 218 * we won't be searching the parent tree. 219 */ 220 if (!ParentNode) 221 { 222 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "[%4.4s] has no parent\n", 223 ACPI_CAST_PTR (char, &TargetName))); 224 return_ACPI_STATUS (AE_NOT_FOUND); 225 } 226 227 if (AcpiNsLocal (Type)) 228 { 229 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 230 "[%4.4s] type [%s] must be local to this scope (no parent search)\n", 231 ACPI_CAST_PTR (char, &TargetName), AcpiUtGetTypeName (Type))); 232 return_ACPI_STATUS (AE_NOT_FOUND); 233 } 234 235 /* Search the parent tree */ 236 237 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 238 "Searching parent [%4.4s] for [%4.4s]\n", 239 AcpiUtGetNodeName (ParentNode), ACPI_CAST_PTR (char, &TargetName))); 240 241 /* Search parents until target is found or we have backed up to the root */ 242 243 while (ParentNode) 244 { 245 /* 246 * Search parent scope. Use TYPE_ANY because we don't care about the 247 * object type at this point, we only care about the existence of 248 * the actual name we are searching for. Typechecking comes later. 249 */ 250 Status = AcpiNsSearchOneScope ( 251 TargetName, ParentNode, ACPI_TYPE_ANY, ReturnNode); 252 if (ACPI_SUCCESS (Status)) 253 { 254 return_ACPI_STATUS (Status); 255 } 256 257 /* Not found here, go up another level (until we reach the root) */ 258 259 ParentNode = ParentNode->Parent; 260 } 261 262 /* Not found in parent tree */ 263 264 return_ACPI_STATUS (AE_NOT_FOUND); 265 } 266 267 268 /******************************************************************************* 269 * 270 * FUNCTION: AcpiNsSearchAndEnter 271 * 272 * PARAMETERS: TargetName - Ascii ACPI name to search for (4 chars) 273 * WalkState - Current state of the walk 274 * Node - Starting node where search will begin 275 * InterpreterMode - Add names only in ACPI_MODE_LOAD_PASS_x. 276 * Otherwise,search only. 277 * Type - Object type to match 278 * Flags - Flags describing the search restrictions 279 * ReturnNode - Where the Node is returned 280 * 281 * RETURN: Status 282 * 283 * DESCRIPTION: Search for a name segment in a single namespace level, 284 * optionally adding it if it is not found. If the passed 285 * Type is not Any and the type previously stored in the 286 * entry was Any (i.e. unknown), update the stored type. 287 * 288 * In ACPI_IMODE_EXECUTE, search only. 289 * In other modes, search and add if not found. 290 * 291 ******************************************************************************/ 292 293 ACPI_STATUS 294 AcpiNsSearchAndEnter ( 295 UINT32 TargetName, 296 ACPI_WALK_STATE *WalkState, 297 ACPI_NAMESPACE_NODE *Node, 298 ACPI_INTERPRETER_MODE InterpreterMode, 299 ACPI_OBJECT_TYPE Type, 300 UINT32 Flags, 301 ACPI_NAMESPACE_NODE **ReturnNode) 302 { 303 ACPI_STATUS Status; 304 ACPI_NAMESPACE_NODE *NewNode; 305 306 307 ACPI_FUNCTION_TRACE (NsSearchAndEnter); 308 309 310 /* Parameter validation */ 311 312 if (!Node || !TargetName || !ReturnNode) 313 { 314 ACPI_ERROR ((AE_INFO, 315 "Null parameter: Node %p Name 0x%X ReturnNode %p", 316 Node, TargetName, ReturnNode)); 317 return_ACPI_STATUS (AE_BAD_PARAMETER); 318 } 319 320 /* 321 * Name must consist of valid ACPI characters. We will repair the name if 322 * necessary because we don't want to abort because of this, but we want 323 * all namespace names to be printable. A warning message is appropriate. 324 * 325 * This issue came up because there are in fact machines that exhibit 326 * this problem, and we want to be able to enable ACPI support for them, 327 * even though there are a few bad names. 328 */ 329 AcpiUtRepairName (ACPI_CAST_PTR (char, &TargetName)); 330 331 /* Try to find the name in the namespace level specified by the caller */ 332 333 *ReturnNode = ACPI_ENTRY_NOT_FOUND; 334 Status = AcpiNsSearchOneScope (TargetName, Node, Type, ReturnNode); 335 if (Status != AE_NOT_FOUND) 336 { 337 /* 338 * If we found it AND the request specifies that a find is an error, 339 * return the error 340 */ 341 if (Status == AE_OK) 342 { 343 /* The node was found in the namespace */ 344 345 /* 346 * If the namespace override feature is enabled for this node, 347 * delete any existing attached sub-object and make the node 348 * look like a new node that is owned by the override table. 349 */ 350 if (Flags & ACPI_NS_OVERRIDE_IF_FOUND) 351 { 352 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 353 "Namespace override: %4.4s pass %u type %X Owner %X\n", 354 ACPI_CAST_PTR(char, &TargetName), InterpreterMode, 355 (*ReturnNode)->Type, WalkState->OwnerId)); 356 357 AcpiNsDeleteChildren (*ReturnNode); 358 if (AcpiGbl_RuntimeNamespaceOverride) 359 { 360 AcpiUtRemoveReference ((*ReturnNode)->Object); 361 (*ReturnNode)->Object = NULL; 362 (*ReturnNode)->OwnerId = WalkState->OwnerId; 363 } 364 else 365 { 366 AcpiNsRemoveNode (*ReturnNode); 367 *ReturnNode = ACPI_ENTRY_NOT_FOUND; 368 } 369 } 370 371 /* Return an error if we don't expect to find the object */ 372 373 else if (Flags & ACPI_NS_ERROR_IF_FOUND) 374 { 375 Status = AE_ALREADY_EXISTS; 376 } 377 } 378 379 #ifdef ACPI_ASL_COMPILER 380 if (*ReturnNode && (*ReturnNode)->Type == ACPI_TYPE_ANY) 381 { 382 (*ReturnNode)->Flags |= ANOBJ_IS_EXTERNAL; 383 } 384 #endif 385 386 /* Either found it or there was an error: finished either way */ 387 388 return_ACPI_STATUS (Status); 389 } 390 391 /* 392 * The name was not found. If we are NOT performing the first pass 393 * (name entry) of loading the namespace, search the parent tree (all the 394 * way to the root if necessary.) We don't want to perform the parent 395 * search when the namespace is actually being loaded. We want to perform 396 * the search when namespace references are being resolved (load pass 2) 397 * and during the execution phase. 398 */ 399 if ((InterpreterMode != ACPI_IMODE_LOAD_PASS1) && 400 (Flags & ACPI_NS_SEARCH_PARENT)) 401 { 402 /* 403 * Not found at this level - search parent tree according to the 404 * ACPI specification 405 */ 406 Status = AcpiNsSearchParentTree (TargetName, Node, Type, ReturnNode); 407 if (ACPI_SUCCESS (Status)) 408 { 409 return_ACPI_STATUS (Status); 410 } 411 } 412 413 /* In execute mode, just search, never add names. Exit now */ 414 415 if (InterpreterMode == ACPI_IMODE_EXECUTE) 416 { 417 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 418 "%4.4s Not found in %p [Not adding]\n", 419 ACPI_CAST_PTR (char, &TargetName), Node)); 420 421 return_ACPI_STATUS (AE_NOT_FOUND); 422 } 423 424 /* Create the new named object */ 425 426 NewNode = AcpiNsCreateNode (TargetName); 427 if (!NewNode) 428 { 429 return_ACPI_STATUS (AE_NO_MEMORY); 430 } 431 432 #ifdef ACPI_ASL_COMPILER 433 434 /* Node is an object defined by an External() statement */ 435 436 if (Flags & ACPI_NS_EXTERNAL || 437 (WalkState && WalkState->Opcode == AML_SCOPE_OP)) 438 { 439 NewNode->Flags |= ANOBJ_IS_EXTERNAL; 440 } 441 #endif 442 443 if (Flags & ACPI_NS_TEMPORARY) 444 { 445 NewNode->Flags |= ANOBJ_TEMPORARY; 446 } 447 448 /* Install the new object into the parent's list of children */ 449 450 AcpiNsInstallNode (WalkState, Node, NewNode, Type); 451 *ReturnNode = NewNode; 452 return_ACPI_STATUS (AE_OK); 453 } 454