drivers/bus/acpi/acpica/executer/exnames.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exnames - interpreter/scanner name load/execute
   4  *
   5  *****************************************************************************/
   6
   7 /******************************************************************************
   8  *
   9  * 1. Copyright Notice
  10  *
  11  * Some or all of this work - Copyright (c) 1999 - 2014, 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 __EXNAMES_C__
 117
 118 #include "acpi.h"
 119 #include "accommon.h"
 120 #include "acinterp.h"
 121 #include "amlcode.h"
 122
 123 #define _COMPONENT          ACPI_EXECUTER
 124         ACPI_MODULE_NAME    ("exnames")
 125
 126 /* Local prototypes */
 127
 128 static char *
 129 AcpiExAllocateNameString (
 130     UINT32                  PrefixCount,
 131     UINT32                  NumNameSegs);
 132
 133 static ACPI_STATUS
 134 AcpiExNameSegment (
 135     UINT8                   **InAmlAddress,
 136     char                    *NameString);
 137
 138
 139 /*******************************************************************************
 140  *
 141  * FUNCTION:    AcpiExAllocateNameString
 142  *
 143  * PARAMETERS:  PrefixCount         - Count of parent levels. Special cases:
 144  *                                    (-1)==root,  0==none
 145  *              NumNameSegs         - count of 4-character name segments
 146  *
 147  * RETURN:      A pointer to the allocated string segment. This segment must
 148  *              be deleted by the caller.
 149  *
 150  * DESCRIPTION: Allocate a buffer for a name string. Ensure allocated name
 151  *              string is long enough, and set up prefix if any.
 152  *
 153  ******************************************************************************/
 154
 155 static char *
 156 AcpiExAllocateNameString (
 157     UINT32                  PrefixCount,
 158     UINT32                  NumNameSegs)
 159 {
 160     char                    *TempPtr;
 161     char                    *NameString;
 162     UINT32                   SizeNeeded;
 163
 164     ACPI_FUNCTION_TRACE (ExAllocateNameString);
 165
 166
 167     /*
 168      * Allow room for all \ and ^ prefixes, all segments and a MultiNamePrefix.
 169      * Also, one byte for the null terminator.
 170      * This may actually be somewhat longer than needed.
 171      */
 172     if (PrefixCount == ACPI_UINT32_MAX)
 173     {
 174         /* Special case for root */
 175
 176         SizeNeeded = 1 + (ACPI_NAME_SIZE * NumNameSegs) + 2 + 1;
 177     }
 178     else
 179     {
 180         SizeNeeded = PrefixCount + (ACPI_NAME_SIZE * NumNameSegs) + 2 + 1;
 181     }
 182
 183     /*
 184      * Allocate a buffer for the name.
 185      * This buffer must be deleted by the caller!
 186      */
 187     NameString = ACPI_ALLOCATE (SizeNeeded);
 188     if (!NameString)
 189     {
 190         ACPI_ERROR ((AE_INFO,
 191             "Could not allocate size %u", SizeNeeded));
 192         return_PTR (NULL);
 193     }
 194
 195     TempPtr = NameString;
 196
 197     /* Set up Root or Parent prefixes if needed */
 198
 199     if (PrefixCount == ACPI_UINT32_MAX)
 200     {
 201         *TempPtr++ = AML_ROOT_PREFIX;
 202     }
 203     else
 204     {
 205         while (PrefixCount--)
 206         {
 207             *TempPtr++ = AML_PARENT_PREFIX;
 208         }
 209     }
 210
 211
 212     /* Set up Dual or Multi prefixes if needed */
 213
 214     if (NumNameSegs > 2)
 215     {
 216         /* Set up multi prefixes   */
 217
 218         *TempPtr++ = AML_MULTI_NAME_PREFIX_OP;
 219         *TempPtr++ = (char) NumNameSegs;
 220     }
 221     else if (2 == NumNameSegs)
 222     {
 223         /* Set up dual prefixes */
 224
 225         *TempPtr++ = AML_DUAL_NAME_PREFIX;
 226     }
 227
 228     /*
 229      * Terminate string following prefixes. AcpiExNameSegment() will
 230      * append the segment(s)
 231      */
 232     *TempPtr = 0;
 233
 234     return_PTR (NameString);
 235 }
 236
 237 /*******************************************************************************
 238  *
 239  * FUNCTION:    AcpiExNameSegment
 240  *
 241  * PARAMETERS:  InAmlAddress    - Pointer to the name in the AML code
 242  *              NameString      - Where to return the name. The name is appended
 243  *                                to any existing string to form a namepath
 244  *
 245  * RETURN:      Status
 246  *
 247  * DESCRIPTION: Extract an ACPI name (4 bytes) from the AML byte stream
 248  *
 249  ******************************************************************************/
 250
 251 static ACPI_STATUS
 252 AcpiExNameSegment (
 253     UINT8                   **InAmlAddress,
 254     char                    *NameString)
 255 {
 256     char                    *AmlAddress = (void *) *InAmlAddress;
 257     ACPI_STATUS             Status = AE_OK;
 258     UINT32                  Index;
 259     char                    CharBuf[5];
 260
 261
 262     ACPI_FUNCTION_TRACE (ExNameSegment);
 263
 264
 265     /*
 266      * If first character is a digit, then we know that we aren't looking at a
 267      * valid name segment
 268      */
 269     CharBuf[0] = *AmlAddress;
 270
 271     if ('0' <= CharBuf[0] && CharBuf[0] <= '9')
 272     {
 273         ACPI_ERROR ((AE_INFO, "Invalid leading digit: %c", CharBuf[0]));
 274         return_ACPI_STATUS (AE_CTRL_PENDING);
 275     }
 276
 277     ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "Bytes from stream:\n"));
 278
 279     for (Index = 0;
 280         (Index < ACPI_NAME_SIZE) && (AcpiUtValidAcpiChar (*AmlAddress, 0));
 281         Index++)
 282     {
 283         CharBuf[Index] = *AmlAddress++;
 284         ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "%c\n", CharBuf[Index]));
 285     }
 286
 287
 288     /* Valid name segment  */
 289
 290     if (Index == 4)
 291     {
 292         /* Found 4 valid characters */
 293
 294         CharBuf[4] = '\0';
 295
 296         if (NameString)
 297         {
 298             ACPI_STRCAT (NameString, CharBuf);
 299             ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
 300                 "Appended to - %s\n", NameString));
 301         }
 302         else
 303         {
 304             ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
 305                 "No Name string - %s\n", CharBuf));
 306         }
 307     }
 308     else if (Index == 0)
 309     {
 310         /*
 311          * First character was not a valid name character,
 312          * so we are looking at something other than a name.
 313          */
 314         ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
 315             "Leading character is not alpha: %02Xh (not a name)\n",
 316             CharBuf[0]));
 317         Status = AE_CTRL_PENDING;
 318     }
 319     else
 320     {
 321         /*
 322          * Segment started with one or more valid characters, but fewer than
 323          * the required 4
 324          */
 325         Status = AE_AML_BAD_NAME;
 326         ACPI_ERROR ((AE_INFO,
 327             "Bad character 0x%02x in name, at %p",
 328             *AmlAddress, AmlAddress));
 329     }
 330
 331     *InAmlAddress = ACPI_CAST_PTR (UINT8, AmlAddress);
 332     return_ACPI_STATUS (Status);
 333 }
 334
 335
 336 /*******************************************************************************
 337  *
 338  * FUNCTION:    AcpiExGetNameString
 339  *
 340  * PARAMETERS:  DataType            - Object type to be associated with this
 341  *                                    name
 342  *              InAmlAddress        - Pointer to the namestring in the AML code
 343  *              OutNameString       - Where the namestring is returned
 344  *              OutNameLength       - Length of the returned string
 345  *
 346  * RETURN:      Status, namestring and length
 347  *
 348  * DESCRIPTION: Extract a full namepath from the AML byte stream,
 349  *              including any prefixes.
 350  *
 351  ******************************************************************************/
 352
 353 ACPI_STATUS
 354 AcpiExGetNameString (
 355     ACPI_OBJECT_TYPE        DataType,
 356     UINT8                   *InAmlAddress,
 357     char                    **OutNameString,
 358     UINT32                  *OutNameLength)
 359 {
 360     ACPI_STATUS             Status = AE_OK;
 361     UINT8                   *AmlAddress = InAmlAddress;
 362     char                    *NameString = NULL;
 363     UINT32                  NumSegments;
 364     UINT32                  PrefixCount = 0;
 365     BOOLEAN                 HasPrefix = FALSE;
 366
 367
 368     ACPI_FUNCTION_TRACE_PTR (ExGetNameString, AmlAddress);
 369
 370
 371     if (ACPI_TYPE_LOCAL_REGION_FIELD == DataType   ||
 372         ACPI_TYPE_LOCAL_BANK_FIELD == DataType     ||
 373         ACPI_TYPE_LOCAL_INDEX_FIELD == DataType)
 374     {
 375         /* Disallow prefixes for types associated with FieldUnit names */
 376
 377         NameString = AcpiExAllocateNameString (0, 1);
 378         if (!NameString)
 379         {
 380             Status = AE_NO_MEMORY;
 381         }
 382         else
 383         {
 384             Status = AcpiExNameSegment (&AmlAddress, NameString);
 385         }
 386     }
 387     else
 388     {
 389         /*
 390          * DataType is not a field name.
 391          * Examine first character of name for root or parent prefix operators
 392          */
 393         switch (*AmlAddress)
 394         {
 395         case AML_ROOT_PREFIX:
 396
 397             ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "RootPrefix(\\) at %p\n",
 398                 AmlAddress));
 399
 400             /*
 401              * Remember that we have a RootPrefix --
 402              * see comment in AcpiExAllocateNameString()
 403              */
 404             AmlAddress++;
 405             PrefixCount = ACPI_UINT32_MAX;
 406             HasPrefix = TRUE;
 407             break;
 408
 409         case AML_PARENT_PREFIX:
 410
 411             /* Increment past possibly multiple parent prefixes */
 412
 413             do
 414             {
 415                 ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "ParentPrefix (^) at %p\n",
 416                     AmlAddress));
 417
 418                 AmlAddress++;
 419                 PrefixCount++;
 420
 421             } while (*AmlAddress == AML_PARENT_PREFIX);
 422
 423             HasPrefix = TRUE;
 424             break;
 425
 426         default:
 427
 428             /* Not a prefix character */
 429
 430             break;
 431         }
 432
 433         /* Examine first character of name for name segment prefix operator */
 434
 435         switch (*AmlAddress)
 436         {
 437         case AML_DUAL_NAME_PREFIX:
 438
 439             ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "DualNamePrefix at %p\n",
 440                 AmlAddress));
 441
 442             AmlAddress++;
 443             NameString = AcpiExAllocateNameString (PrefixCount, 2);
 444             if (!NameString)
 445             {
 446                 Status = AE_NO_MEMORY;
 447                 break;
 448             }
 449
 450             /* Indicate that we processed a prefix */
 451
 452             HasPrefix = TRUE;
 453
 454             Status = AcpiExNameSegment (&AmlAddress, NameString);
 455             if (ACPI_SUCCESS (Status))
 456             {
 457                 Status = AcpiExNameSegment (&AmlAddress, NameString);
 458             }
 459             break;
 460
 461         case AML_MULTI_NAME_PREFIX_OP:
 462
 463             ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "MultiNamePrefix at %p\n",
 464                 AmlAddress));
 465
 466             /* Fetch count of segments remaining in name path */
 467
 468             AmlAddress++;
 469             NumSegments = *AmlAddress;
 470
 471             NameString = AcpiExAllocateNameString (PrefixCount, NumSegments);
 472             if (!NameString)
 473             {
 474                 Status = AE_NO_MEMORY;
 475                 break;
 476             }
 477
 478             /* Indicate that we processed a prefix */
 479
 480             AmlAddress++;
 481             HasPrefix = TRUE;
 482
 483             while (NumSegments &&
 484                     (Status = AcpiExNameSegment (&AmlAddress, NameString)) ==
 485                         AE_OK)
 486             {
 487                 NumSegments--;
 488             }
 489
 490             break;
 491
 492         case 0:
 493
 494             /* NullName valid as of 8-12-98 ASL/AML Grammar Update */
 495
 496             if (PrefixCount == ACPI_UINT32_MAX)
 497             {
 498                 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 499                     "NameSeg is \"\\\" followed by NULL\n"));
 500             }
 501
 502             /* Consume the NULL byte */
 503
 504             AmlAddress++;
 505             NameString = AcpiExAllocateNameString (PrefixCount, 0);
 506             if (!NameString)
 507             {
 508                 Status = AE_NO_MEMORY;
 509                 break;
 510             }
 511
 512             break;
 513
 514         default:
 515
 516             /* Name segment string */
 517
 518             NameString = AcpiExAllocateNameString (PrefixCount, 1);
 519             if (!NameString)
 520             {
 521                 Status = AE_NO_MEMORY;
 522                 break;
 523             }
 524
 525             Status = AcpiExNameSegment (&AmlAddress, NameString);
 526             break;
 527         }
 528     }
 529
 530     if (AE_CTRL_PENDING == Status && HasPrefix)
 531     {
 532         /* Ran out of segments after processing a prefix */
 533
 534         ACPI_ERROR ((AE_INFO,
 535             "Malformed Name at %p", NameString));
 536         Status = AE_AML_BAD_NAME;
 537     }
 538
 539     if (ACPI_FAILURE (Status))
 540     {
 541         if (NameString)
 542         {
 543             ACPI_FREE (NameString);
 544         }
 545         return_ACPI_STATUS (Status);
 546     }
 547
 548     *OutNameString = NameString;
 549     *OutNameLength = (UINT32) (AmlAddress - InAmlAddress);
 550
 551     return_ACPI_STATUS (Status);
 552 }