drivers/bus/acpi/acpica/namespace/nsnames.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: nsnames - Name manipulation and search
   4  *
   5  ******************************************************************************/
   6
   7 /******************************************************************************
   8  *
   9  * 1. Copyright Notice
  10  *
  11  * Some or all of this work - Copyright (c) 1999 - 2011, Intel Corp.
  12  * All rights reserved.
  13  *
  14  * 2. License
  15  *
  16  * 2.1. This is your license from Intel Corp. under its intellectual property
  17  * rights.  You may have additional license terms from the party that provided
  18  * you this software, covering your right to use that party's intellectual
  19  * property rights.
  20  *
  21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  22  * copy of the source code appearing in this file ("Covered Code") an
  23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  24  * base code distributed originally by Intel ("Original Intel Code") to copy,
  25  * make derivatives, distribute, use and display any portion of the Covered
  26  * Code in any form, with the right to sublicense such rights; and
  27  *
  28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  29  * license (with the right to sublicense), under only those claims of Intel
  30  * patents that are infringed by the Original Intel Code, to make, use, sell,
  31  * offer to sell, and import the Covered Code and derivative works thereof
  32  * solely to the minimum extent necessary to exercise the above copyright
  33  * license, and in no event shall the patent license extend to any additions
  34  * to or modifications of the Original Intel Code.  No other license or right
  35  * is granted directly or by implication, estoppel or otherwise;
  36  *
  37  * The above copyright and patent license is granted only if the following
  38  * conditions are met:
  39  *
  40  * 3. Conditions
  41  *
  42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  43  * Redistribution of source code of any substantial portion of the Covered
  44  * Code or modification with rights to further distribute source must include
  45  * the above Copyright Notice, the above License, this list of Conditions,
  46  * and the following Disclaimer and Export Compliance provision.  In addition,
  47  * Licensee must cause all Covered Code to which Licensee contributes to
  48  * contain a file documenting the changes Licensee made to create that Covered
  49  * Code and the date of any change.  Licensee must include in that file the
  50  * documentation of any changes made by any predecessor Licensee.  Licensee
  51  * must include a prominent statement that the modification is derived,
  52  * directly or indirectly, from Original Intel Code.
  53  *
  54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  55  * Redistribution of source code of any substantial portion of the Covered
  56  * Code or modification without rights to further distribute source must
  57  * include the following Disclaimer and Export Compliance provision in the
  58  * documentation and/or other materials provided with distribution.  In
  59  * addition, Licensee may not authorize further sublicense of source of any
  60  * portion of the Covered Code, and must include terms to the effect that the
  61  * license from Licensee to its licensee is limited to the intellectual
  62  * property embodied in the software Licensee provides to its licensee, and
  63  * not to intellectual property embodied in modifications its licensee may
  64  * make.
  65  *
  66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  67  * substantial portion of the Covered Code or modification must reproduce the
  68  * above Copyright Notice, and the following Disclaimer and Export Compliance
  69  * provision in the documentation and/or other materials provided with the
  70  * distribution.
  71  *
  72  * 3.4. Intel retains all right, title, and interest in and to the Original
  73  * Intel Code.
  74  *
  75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  76  * Intel shall be used in advertising or otherwise to promote the sale, use or
  77  * other dealings in products derived from or relating to the Covered Code
  78  * without prior written authorization from Intel.
  79  *
  80  * 4. Disclaimer and Export Compliance
  81  *
  82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  83  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
  85  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
  86  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
  87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
  88  * PARTICULAR PURPOSE.
  89  *
  90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
  91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
  92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
  93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
  94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
  95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
  96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
  97  * LIMITED REMEDY.
  98  *
  99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
 100  * software or system incorporating such software without first obtaining any
 101  * required license or other approval from the U. S. Department of Commerce or
 102  * any other agency or department of the United States Government.  In the
 103  * event Licensee exports any such software from the United States or
 104  * re-exports any such software from a foreign destination, Licensee shall
 105  * ensure that the distribution and export/re-export of the software is in
 106  * compliance with all laws, regulations, orders, or other restrictions of the
 107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
 108  * any of its subsidiaries will export/re-export any technical data, process,
 109  * software, or service, directly or indirectly, to any country for which the
 110  * United States government or any agency thereof requires an export license,
 111  * other governmental approval, or letter of assurance, without first obtaining
 112  * such license, approval or letter.
 113  *
 114  *****************************************************************************/
 115
 116 #define __NSNAMES_C__
 117
 118 #include "acpi.h"
 119 #include "accommon.h"
 120 #include "amlcode.h"
 121 #include "acnamesp.h"
 122
 123
 124 #define _COMPONENT          ACPI_NAMESPACE
 125         ACPI_MODULE_NAME    ("nsnames")
 126
 127
 128 /*******************************************************************************
 129  *
 130  * FUNCTION:    AcpiNsBuildExternalPath
 131  *
 132  * PARAMETERS:  Node            - NS node whose pathname is needed
 133  *              Size            - Size of the pathname
 134  *              *NameBuffer     - Where to return the pathname
 135  *
 136  * RETURN:      Status
 137  *              Places the pathname into the NameBuffer, in external format
 138  *              (name segments separated by path separators)
 139  *
 140  * DESCRIPTION: Generate a full pathaname
 141  *
 142  ******************************************************************************/
 143
 144 ACPI_STATUS
 145 AcpiNsBuildExternalPath (
 146     ACPI_NAMESPACE_NODE     *Node,
 147     ACPI_SIZE               Size,
 148     char                    *NameBuffer)
 149 {
 150     ACPI_SIZE               Index;
 151     ACPI_NAMESPACE_NODE     *ParentNode;
 152
 153
 154     ACPI_FUNCTION_ENTRY ();
 155
 156
 157     /* Special case for root */
 158
 159     Index = Size - 1;
 160     if (Index < ACPI_NAME_SIZE)
 161     {
 162         NameBuffer[0] = AML_ROOT_PREFIX;
 163         NameBuffer[1] = 0;
 164         return (AE_OK);
 165     }
 166
 167     /* Store terminator byte, then build name backwards */
 168
 169     ParentNode = Node;
 170     NameBuffer[Index] = 0;
 171
 172     while ((Index > ACPI_NAME_SIZE) && (ParentNode != AcpiGbl_RootNode))
 173     {
 174         Index -= ACPI_NAME_SIZE;
 175
 176         /* Put the name into the buffer */
 177
 178         ACPI_MOVE_32_TO_32 ((NameBuffer + Index), &ParentNode->Name);
 179         ParentNode = ParentNode->Parent;
 180
 181         /* Prefix name with the path separator */
 182
 183         Index--;
 184         NameBuffer[Index] = ACPI_PATH_SEPARATOR;
 185     }
 186
 187     /* Overwrite final separator with the root prefix character */
 188
 189     NameBuffer[Index] = AML_ROOT_PREFIX;
 190
 191     if (Index != 0)
 192     {
 193         ACPI_ERROR ((AE_INFO,
 194             "Could not construct external pathname; index=%u, size=%u, Path=%s",
 195             (UINT32) Index, (UINT32) Size, &NameBuffer[Size]));
 196
 197         return (AE_BAD_PARAMETER);
 198     }
 199
 200     return (AE_OK);
 201 }
 202
 203
 204 /*******************************************************************************
 205  *
 206  * FUNCTION:    AcpiNsGetExternalPathname
 207  *
 208  * PARAMETERS:  Node            - Namespace node whose pathname is needed
 209  *
 210  * RETURN:      Pointer to storage containing the fully qualified name of
 211  *              the node, In external format (name segments separated by path
 212  *              separators.)
 213  *
 214  * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
 215  *              for error and debug statements.
 216  *
 217  ******************************************************************************/
 218
 219 char *
 220 AcpiNsGetExternalPathname (
 221     ACPI_NAMESPACE_NODE     *Node)
 222 {
 223     ACPI_STATUS             Status;
 224     char                    *NameBuffer;
 225     ACPI_SIZE               Size;
 226
 227
 228     ACPI_FUNCTION_TRACE_PTR (NsGetExternalPathname, Node);
 229
 230
 231     /* Calculate required buffer size based on depth below root */
 232
 233     Size = AcpiNsGetPathnameLength (Node);
 234     if (!Size)
 235     {
 236         return_PTR (NULL);
 237     }
 238
 239     /* Allocate a buffer to be returned to caller */
 240
 241     NameBuffer = ACPI_ALLOCATE_ZEROED (Size);
 242     if (!NameBuffer)
 243     {
 244         ACPI_ERROR ((AE_INFO, "Could not allocate %u bytes", (UINT32) Size));
 245         return_PTR (NULL);
 246     }
 247
 248     /* Build the path in the allocated buffer */
 249
 250     Status = AcpiNsBuildExternalPath (Node, Size, NameBuffer);
 251     if (ACPI_FAILURE (Status))
 252     {
 253         ACPI_FREE (NameBuffer);
 254         return_PTR (NULL);
 255     }
 256
 257     return_PTR (NameBuffer);
 258 }
 259
 260
 261 /*******************************************************************************
 262  *
 263  * FUNCTION:    AcpiNsGetPathnameLength
 264  *
 265  * PARAMETERS:  Node        - Namespace node
 266  *
 267  * RETURN:      Length of path, including prefix
 268  *
 269  * DESCRIPTION: Get the length of the pathname string for this node
 270  *
 271  ******************************************************************************/
 272
 273 ACPI_SIZE
 274 AcpiNsGetPathnameLength (
 275     ACPI_NAMESPACE_NODE     *Node)
 276 {
 277     ACPI_SIZE               Size;
 278     ACPI_NAMESPACE_NODE     *NextNode;
 279
 280
 281     ACPI_FUNCTION_ENTRY ();
 282
 283
 284     /*
 285      * Compute length of pathname as 5 * number of name segments.
 286      * Go back up the parent tree to the root
 287      */
 288     Size = 0;
 289     NextNode = Node;
 290
 291     while (NextNode && (NextNode != AcpiGbl_RootNode))
 292     {
 293         if (ACPI_GET_DESCRIPTOR_TYPE (NextNode) != ACPI_DESC_TYPE_NAMED)
 294         {
 295             ACPI_ERROR ((AE_INFO,
 296                 "Invalid Namespace Node (%p) while traversing namespace",
 297                 NextNode));
 298             return 0;
 299         }
 300         Size += ACPI_PATH_SEGMENT_LENGTH;
 301         NextNode = NextNode->Parent;
 302     }
 303
 304     if (!Size)
 305     {
 306         Size = 1; /* Root node case */
 307     }
 308
 309     return (Size + 1);  /* +1 for null string terminator */
 310 }
 311
 312
 313 /*******************************************************************************
 314  *
 315  * FUNCTION:    AcpiNsHandleToPathname
 316  *
 317  * PARAMETERS:  TargetHandle            - Handle of named object whose name is
 318  *                                        to be found
 319  *              Buffer                  - Where the pathname is returned
 320  *
 321  * RETURN:      Status, Buffer is filled with pathname if status is AE_OK
 322  *
 323  * DESCRIPTION: Build and return a full namespace pathname
 324  *
 325  ******************************************************************************/
 326
 327 ACPI_STATUS
 328 AcpiNsHandleToPathname (
 329     ACPI_HANDLE             TargetHandle,
 330     ACPI_BUFFER             *Buffer)
 331 {
 332     ACPI_STATUS             Status;
 333     ACPI_NAMESPACE_NODE     *Node;
 334     ACPI_SIZE               RequiredSize;
 335
 336
 337     ACPI_FUNCTION_TRACE_PTR (NsHandleToPathname, TargetHandle);
 338
 339
 340     Node = AcpiNsValidateHandle (TargetHandle);
 341     if (!Node)
 342     {
 343         return_ACPI_STATUS (AE_BAD_PARAMETER);
 344     }
 345
 346     /* Determine size required for the caller buffer */
 347
 348     RequiredSize = AcpiNsGetPathnameLength (Node);
 349     if (!RequiredSize)
 350     {
 351         return_ACPI_STATUS (AE_BAD_PARAMETER);
 352     }
 353
 354     /* Validate/Allocate/Clear caller buffer */
 355
 356     Status = AcpiUtInitializeBuffer (Buffer, RequiredSize);
 357     if (ACPI_FAILURE (Status))
 358     {
 359         return_ACPI_STATUS (Status);
 360     }
 361
 362     /* Build the path in the caller buffer */
 363
 364     Status = AcpiNsBuildExternalPath (Node, RequiredSize, Buffer->Pointer);
 365     if (ACPI_FAILURE (Status))
 366     {
 367         return_ACPI_STATUS (Status);
 368     }
 369
 370     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%s [%X]\n",
 371         (char *) Buffer->Pointer, (UINT32) RequiredSize));
 372     return_ACPI_STATUS (AE_OK);
 373 }
 374
 375