1 /****************************************************************************** 2 * 3 * Module Name: nswalk - Functions for walking the 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 <contrib/dev/acpica/include/acpi.h> 45 #include <contrib/dev/acpica/include/accommon.h> 46 #include <contrib/dev/acpica/include/acnamesp.h> 47 48 49 #define _COMPONENT ACPI_NAMESPACE 50 ACPI_MODULE_NAME ("nswalk") 51 52 53 /******************************************************************************* 54 * 55 * FUNCTION: AcpiNsGetNextNode 56 * 57 * PARAMETERS: ParentNode - Parent node whose children we are 58 * getting 59 * ChildNode - Previous child that was found. 60 * The NEXT child will be returned 61 * 62 * RETURN: ACPI_NAMESPACE_NODE - Pointer to the NEXT child or NULL if 63 * none is found. 64 * 65 * DESCRIPTION: Return the next peer node within the namespace. If Handle 66 * is valid, Scope is ignored. Otherwise, the first node 67 * within Scope is returned. 68 * 69 ******************************************************************************/ 70 71 ACPI_NAMESPACE_NODE * 72 AcpiNsGetNextNode ( 73 ACPI_NAMESPACE_NODE *ParentNode, 74 ACPI_NAMESPACE_NODE *ChildNode) 75 { 76 ACPI_FUNCTION_ENTRY (); 77 78 79 if (!ChildNode) 80 { 81 /* It's really the parent's _scope_ that we want */ 82 83 return (ParentNode->Child); 84 } 85 86 /* Otherwise just return the next peer */ 87 88 return (ChildNode->Peer); 89 } 90 91 92 /******************************************************************************* 93 * 94 * FUNCTION: AcpiNsGetNextNodeTyped 95 * 96 * PARAMETERS: Type - Type of node to be searched for 97 * ParentNode - Parent node whose children we are 98 * getting 99 * ChildNode - Previous child that was found. 100 * The NEXT child will be returned 101 * 102 * RETURN: ACPI_NAMESPACE_NODE - Pointer to the NEXT child or NULL if 103 * none is found. 104 * 105 * DESCRIPTION: Return the next peer node within the namespace. If Handle 106 * is valid, Scope is ignored. Otherwise, the first node 107 * within Scope is returned. 108 * 109 ******************************************************************************/ 110 111 ACPI_NAMESPACE_NODE * 112 AcpiNsGetNextNodeTyped ( 113 ACPI_OBJECT_TYPE Type, 114 ACPI_NAMESPACE_NODE *ParentNode, 115 ACPI_NAMESPACE_NODE *ChildNode) 116 { 117 ACPI_NAMESPACE_NODE *NextNode = NULL; 118 119 120 ACPI_FUNCTION_ENTRY (); 121 122 123 NextNode = AcpiNsGetNextNode (ParentNode, ChildNode); 124 125 /* If any type is OK, we are done */ 126 127 if (Type == ACPI_TYPE_ANY) 128 { 129 /* NextNode is NULL if we are at the end-of-list */ 130 131 return (NextNode); 132 } 133 134 /* Must search for the node -- but within this scope only */ 135 136 while (NextNode) 137 { 138 /* If type matches, we are done */ 139 140 if (NextNode->Type == Type) 141 { 142 return (NextNode); 143 } 144 145 /* Otherwise, move on to the next peer node */ 146 147 NextNode = NextNode->Peer; 148 } 149 150 /* Not found */ 151 152 return (NULL); 153 } 154 155 156 /******************************************************************************* 157 * 158 * FUNCTION: AcpiNsWalkNamespace 159 * 160 * PARAMETERS: Type - ACPI_OBJECT_TYPE to search for 161 * StartNode - Handle in namespace where search begins 162 * MaxDepth - Depth to which search is to reach 163 * Flags - Whether to unlock the NS before invoking 164 * the callback routine 165 * DescendingCallback - Called during tree descent 166 * when an object of "Type" is found 167 * AscendingCallback - Called during tree ascent 168 * when an object of "Type" is found 169 * Context - Passed to user function(s) above 170 * ReturnValue - from the UserFunction if terminated 171 * early. Otherwise, returns NULL. 172 * RETURNS: Status 173 * 174 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree, 175 * starting (and ending) at the node specified by StartHandle. 176 * The callback function is called whenever a node that matches 177 * the type parameter is found. If the callback function returns 178 * a non-zero value, the search is terminated immediately and 179 * this value is returned to the caller. 180 * 181 * The point of this procedure is to provide a generic namespace 182 * walk routine that can be called from multiple places to 183 * provide multiple services; the callback function(s) can be 184 * tailored to each task, whether it is a print function, 185 * a compare function, etc. 186 * 187 ******************************************************************************/ 188 189 ACPI_STATUS 190 AcpiNsWalkNamespace ( 191 ACPI_OBJECT_TYPE Type, 192 ACPI_HANDLE StartNode, 193 UINT32 MaxDepth, 194 UINT32 Flags, 195 ACPI_WALK_CALLBACK DescendingCallback, 196 ACPI_WALK_CALLBACK AscendingCallback, 197 void *Context, 198 void **ReturnValue) 199 { 200 ACPI_STATUS Status; 201 ACPI_STATUS MutexStatus; 202 ACPI_NAMESPACE_NODE *ChildNode; 203 ACPI_NAMESPACE_NODE *ParentNode; 204 ACPI_OBJECT_TYPE ChildType; 205 UINT32 Level; 206 BOOLEAN NodePreviouslyVisited = FALSE; 207 208 209 ACPI_FUNCTION_TRACE (NsWalkNamespace); 210 211 212 /* Special case for the namespace Root Node */ 213 214 if (StartNode == ACPI_ROOT_OBJECT) 215 { 216 StartNode = AcpiGbl_RootNode; 217 } 218 219 /* Null child means "get first node" */ 220 221 ParentNode = StartNode; 222 ChildNode = AcpiNsGetNextNode (ParentNode, NULL); 223 ChildType = ACPI_TYPE_ANY; 224 Level = 1; 225 226 /* 227 * Traverse the tree of nodes until we bubble back up to where we 228 * started. When Level is zero, the loop is done because we have 229 * bubbled up to (and passed) the original parent handle (StartEntry) 230 */ 231 while (Level > 0 && ChildNode) 232 { 233 Status = AE_OK; 234 235 /* Found next child, get the type if we are not searching for ANY */ 236 237 if (Type != ACPI_TYPE_ANY) 238 { 239 ChildType = ChildNode->Type; 240 } 241 242 /* 243 * Ignore all temporary namespace nodes (created during control 244 * method execution) unless told otherwise. These temporary nodes 245 * can cause a race condition because they can be deleted during 246 * the execution of the user function (if the namespace is 247 * unlocked before invocation of the user function.) Only the 248 * debugger namespace dump will examine the temporary nodes. 249 */ 250 if ((ChildNode->Flags & ANOBJ_TEMPORARY) && 251 !(Flags & ACPI_NS_WALK_TEMP_NODES)) 252 { 253 Status = AE_CTRL_DEPTH; 254 } 255 256 /* Type must match requested type */ 257 258 else if (ChildType == Type) 259 { 260 /* 261 * Found a matching node, invoke the user callback function. 262 * Unlock the namespace if flag is set. 263 */ 264 if (Flags & ACPI_NS_WALK_UNLOCK) 265 { 266 MutexStatus = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE); 267 if (ACPI_FAILURE (MutexStatus)) 268 { 269 return_ACPI_STATUS (MutexStatus); 270 } 271 } 272 273 /* 274 * Invoke the user function, either descending, ascending, 275 * or both. 276 */ 277 if (!NodePreviouslyVisited) 278 { 279 if (DescendingCallback) 280 { 281 Status = DescendingCallback (ChildNode, Level, 282 Context, ReturnValue); 283 } 284 } 285 else 286 { 287 if (AscendingCallback) 288 { 289 Status = AscendingCallback (ChildNode, Level, 290 Context, ReturnValue); 291 } 292 } 293 294 if (Flags & ACPI_NS_WALK_UNLOCK) 295 { 296 MutexStatus = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE); 297 if (ACPI_FAILURE (MutexStatus)) 298 { 299 return_ACPI_STATUS (MutexStatus); 300 } 301 } 302 303 switch (Status) 304 { 305 case AE_OK: 306 case AE_CTRL_DEPTH: 307 308 /* Just keep going */ 309 break; 310 311 case AE_CTRL_TERMINATE: 312 313 /* Exit now, with OK status */ 314 315 return_ACPI_STATUS (AE_OK); 316 317 default: 318 319 /* All others are valid exceptions */ 320 321 return_ACPI_STATUS (Status); 322 } 323 } 324 325 /* 326 * Depth first search: Attempt to go down another level in the 327 * namespace if we are allowed to. Don't go any further if we have 328 * reached the caller specified maximum depth or if the user 329 * function has specified that the maximum depth has been reached. 330 */ 331 if (!NodePreviouslyVisited && 332 (Level < MaxDepth) && 333 (Status != AE_CTRL_DEPTH)) 334 { 335 if (ChildNode->Child) 336 { 337 /* There is at least one child of this node, visit it */ 338 339 Level++; 340 ParentNode = ChildNode; 341 ChildNode = AcpiNsGetNextNode (ParentNode, NULL); 342 continue; 343 } 344 } 345 346 /* No more children, re-visit this node */ 347 348 if (!NodePreviouslyVisited) 349 { 350 NodePreviouslyVisited = TRUE; 351 continue; 352 } 353 354 /* No more children, visit peers */ 355 356 ChildNode = AcpiNsGetNextNode (ParentNode, ChildNode); 357 if (ChildNode) 358 { 359 NodePreviouslyVisited = FALSE; 360 } 361 362 /* No peers, re-visit parent */ 363 364 else 365 { 366 /* 367 * No more children of this node (AcpiNsGetNextNode failed), go 368 * back upwards in the namespace tree to the node's parent. 369 */ 370 Level--; 371 ChildNode = ParentNode; 372 ParentNode = ParentNode->Parent; 373 374 NodePreviouslyVisited = TRUE; 375 } 376 } 377 378 /* Complete walk, not terminated by user function */ 379 380 return_ACPI_STATUS (AE_OK); 381 } 382