drivers/acpi/utilities/utcache.c

   1 /******************************************************************************
   2  *
   3  * Module Name: utcache - local cache allocation routines
   4  *
   5  *****************************************************************************/
   6
   7 /******************************************************************************
   8  *
   9  * 1. Copyright Notice
  10  *
  11  * Some or all of this work - Copyright (c) 1999 - 2010, 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 __UTCACHE_C__
 117
 118 #include "acpi.h"
 119 #include "accommon.h"
 120
 121 #define _COMPONENT          ACPI_UTILITIES
 122         ACPI_MODULE_NAME    ("utcache")
 123
 124
 125 #ifdef ACPI_USE_LOCAL_CACHE
 126 /*******************************************************************************
 127  *
 128  * FUNCTION:    AcpiOsCreateCache
 129  *
 130  * PARAMETERS:  CacheName       - Ascii name for the cache
 131  *              ObjectSize      - Size of each cached object
 132  *              MaxDepth        - Maximum depth of the cache (in objects)
 133  *              ReturnCache     - Where the new cache object is returned
 134  *
 135  * RETURN:      Status
 136  *
 137  * DESCRIPTION: Create a cache object
 138  *
 139  ******************************************************************************/
 140
 141 ACPI_STATUS
 142 AcpiOsCreateCache (
 143     char                    *CacheName,
 144     UINT16                  ObjectSize,
 145     UINT16                  MaxDepth,
 146     ACPI_MEMORY_LIST        **ReturnCache)
 147 {
 148     ACPI_MEMORY_LIST        *Cache;
 149
 150
 151     ACPI_FUNCTION_ENTRY ();
 152
 153
 154     if (!CacheName || !ReturnCache || (ObjectSize < 16))
 155     {
 156         return (AE_BAD_PARAMETER);
 157     }
 158
 159     /* Create the cache object */
 160
 161     Cache = AcpiOsAllocate (sizeof (ACPI_MEMORY_LIST));
 162     if (!Cache)
 163     {
 164         return (AE_NO_MEMORY);
 165     }
 166
 167     /* Populate the cache object and return it */
 168
 169     ACPI_MEMSET (Cache, 0, sizeof (ACPI_MEMORY_LIST));
 170     Cache->LinkOffset = 8;
 171     Cache->ListName   = CacheName;
 172     Cache->ObjectSize = ObjectSize;
 173     Cache->MaxDepth   = MaxDepth;
 174
 175     *ReturnCache = Cache;
 176     return (AE_OK);
 177 }
 178
 179
 180 /*******************************************************************************
 181  *
 182  * FUNCTION:    AcpiOsPurgeCache
 183  *
 184  * PARAMETERS:  Cache           - Handle to cache object
 185  *
 186  * RETURN:      Status
 187  *
 188  * DESCRIPTION: Free all objects within the requested cache.
 189  *
 190  ******************************************************************************/
 191
 192 ACPI_STATUS
 193 AcpiOsPurgeCache (
 194     ACPI_MEMORY_LIST        *Cache)
 195 {
 196     char                    *Next;
 197     ACPI_STATUS             Status;
 198
 199
 200     ACPI_FUNCTION_ENTRY ();
 201
 202
 203     if (!Cache)
 204     {
 205         return (AE_BAD_PARAMETER);
 206     }
 207
 208     Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
 209     if (ACPI_FAILURE (Status))
 210     {
 211         return (Status);
 212     }
 213
 214     /* Walk the list of objects in this cache */
 215
 216     while (Cache->ListHead)
 217     {
 218         /* Delete and unlink one cached state object */
 219
 220         Next = *(ACPI_CAST_INDIRECT_PTR (char,
 221                     &(((char *) Cache->ListHead)[Cache->LinkOffset])));
 222         ACPI_FREE (Cache->ListHead);
 223
 224         Cache->ListHead = Next;
 225         Cache->CurrentDepth--;
 226     }
 227
 228     (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
 229     return (AE_OK);
 230 }
 231
 232
 233 /*******************************************************************************
 234  *
 235  * FUNCTION:    AcpiOsDeleteCache
 236  *
 237  * PARAMETERS:  Cache           - Handle to cache object
 238  *
 239  * RETURN:      Status
 240  *
 241  * DESCRIPTION: Free all objects within the requested cache and delete the
 242  *              cache object.
 243  *
 244  ******************************************************************************/
 245
 246 ACPI_STATUS
 247 AcpiOsDeleteCache (
 248     ACPI_MEMORY_LIST        *Cache)
 249 {
 250     ACPI_STATUS             Status;
 251
 252
 253     ACPI_FUNCTION_ENTRY ();
 254
 255
 256    /* Purge all objects in the cache */
 257
 258     Status = AcpiOsPurgeCache (Cache);
 259     if (ACPI_FAILURE (Status))
 260     {
 261         return (Status);
 262     }
 263
 264     /* Now we can delete the cache object */
 265
 266     AcpiOsFree (Cache);
 267     return (AE_OK);
 268 }
 269
 270
 271 /*******************************************************************************
 272  *
 273  * FUNCTION:    AcpiOsReleaseObject
 274  *
 275  * PARAMETERS:  Cache       - Handle to cache object
 276  *              Object      - The object to be released
 277  *
 278  * RETURN:      None
 279  *
 280  * DESCRIPTION: Release an object to the specified cache.  If cache is full,
 281  *              the object is deleted.
 282  *
 283  ******************************************************************************/
 284
 285 ACPI_STATUS
 286 AcpiOsReleaseObject (
 287     ACPI_MEMORY_LIST        *Cache,
 288     void                    *Object)
 289 {
 290     ACPI_STATUS             Status;
 291
 292
 293     ACPI_FUNCTION_ENTRY ();
 294
 295
 296     if (!Cache || !Object)
 297     {
 298         return (AE_BAD_PARAMETER);
 299     }
 300
 301     /* If cache is full, just free this object */
 302
 303     if (Cache->CurrentDepth >= Cache->MaxDepth)
 304     {
 305         ACPI_FREE (Object);
 306         ACPI_MEM_TRACKING (Cache->TotalFreed++);
 307     }
 308
 309     /* Otherwise put this object back into the cache */
 310
 311     else
 312     {
 313         Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
 314         if (ACPI_FAILURE (Status))
 315         {
 316             return (Status);
 317         }
 318
 319         /* Mark the object as cached */
 320
 321         ACPI_MEMSET (Object, 0xCA, Cache->ObjectSize);
 322         ACPI_SET_DESCRIPTOR_TYPE (Object, ACPI_DESC_TYPE_CACHED);
 323
 324         /* Put the object at the head of the cache list */
 325
 326         * (ACPI_CAST_INDIRECT_PTR (char,
 327             &(((char *) Object)[Cache->LinkOffset]))) = Cache->ListHead;
 328         Cache->ListHead = Object;
 329         Cache->CurrentDepth++;
 330
 331         (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
 332     }
 333
 334     return (AE_OK);
 335 }
 336
 337
 338 /*******************************************************************************
 339  *
 340  * FUNCTION:    AcpiOsAcquireObject
 341  *
 342  * PARAMETERS:  Cache           - Handle to cache object
 343  *
 344  * RETURN:      the acquired object.  NULL on error
 345  *
 346  * DESCRIPTION: Get an object from the specified cache.  If cache is empty,
 347  *              the object is allocated.
 348  *
 349  ******************************************************************************/
 350
 351 void *
 352 AcpiOsAcquireObject (
 353     ACPI_MEMORY_LIST        *Cache)
 354 {
 355     ACPI_STATUS             Status;
 356     void                    *Object;
 357
 358
 359     ACPI_FUNCTION_NAME (OsAcquireObject);
 360
 361
 362     if (!Cache)
 363     {
 364         return (NULL);
 365     }
 366
 367     Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
 368     if (ACPI_FAILURE (Status))
 369     {
 370         return (NULL);
 371     }
 372
 373     ACPI_MEM_TRACKING (Cache->Requests++);
 374
 375     /* Check the cache first */
 376
 377     if (Cache->ListHead)
 378     {
 379         /* There is an object available, use it */
 380
 381         Object = Cache->ListHead;
 382         Cache->ListHead = *(ACPI_CAST_INDIRECT_PTR (char,
 383                                 &(((char *) Object)[Cache->LinkOffset])));
 384
 385         Cache->CurrentDepth--;
 386
 387         ACPI_MEM_TRACKING (Cache->Hits++);
 388         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 389             "Object %p from %s cache\n", Object, Cache->ListName));
 390
 391         Status = AcpiUtReleaseMutex (ACPI_MTX_CACHES);
 392         if (ACPI_FAILURE (Status))
 393         {
 394             return (NULL);
 395         }
 396
 397         /* Clear (zero) the previously used Object */
 398
 399         ACPI_MEMSET (Object, 0, Cache->ObjectSize);
 400     }
 401     else
 402     {
 403         /* The cache is empty, create a new object */
 404
 405         ACPI_MEM_TRACKING (Cache->TotalAllocated++);
 406
 407 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
 408         if ((Cache->TotalAllocated - Cache->TotalFreed) > Cache->MaxOccupied)
 409         {
 410             Cache->MaxOccupied = Cache->TotalAllocated - Cache->TotalFreed;
 411         }
 412 #endif
 413
 414         /* Avoid deadlock with ACPI_ALLOCATE_ZEROED */
 415
 416         Status = AcpiUtReleaseMutex (ACPI_MTX_CACHES);
 417         if (ACPI_FAILURE (Status))
 418         {
 419             return (NULL);
 420         }
 421
 422         Object = ACPI_ALLOCATE_ZEROED (Cache->ObjectSize);
 423         if (!Object)
 424         {
 425             return (NULL);
 426         }
 427     }
 428
 429     return (Object);
 430 }
 431 #endif /* ACPI_USE_LOCAL_CACHE */
 432
 433