drivers/acpi/acpica/utmutex.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: utmutex - local mutex support
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2011, 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/acpi.h>
  45 #include "accommon.h"
  46
  47 #define _COMPONENT          ACPI_UTILITIES
  48 ACPI_MODULE_NAME("utmutex")
  49
  50 /* Local prototypes */
  51 static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id);
  52
  53 static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id);
  54
  55 /*******************************************************************************
  56  *
  57  * FUNCTION:    acpi_ut_mutex_initialize
  58  *
  59  * PARAMETERS:  None.
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: Create the system mutex objects. This includes mutexes,
  64  *              spin locks, and reader/writer locks.
  65  *
  66  ******************************************************************************/
  67
  68 acpi_status acpi_ut_mutex_initialize(void)
  69 {
  70         u32 i;
  71         acpi_status status;
  72
  73         ACPI_FUNCTION_TRACE(ut_mutex_initialize);
  74
  75         /* Create each of the predefined mutex objects */
  76
  77         for (i = 0; i < ACPI_NUM_MUTEX; i++) {
  78                 status = acpi_ut_create_mutex(i);
  79                 if (ACPI_FAILURE(status)) {
  80                         return_ACPI_STATUS(status);
  81                 }
  82         }
  83
  84         /* Create the spinlocks for use at interrupt level */
  85
  86         status = acpi_os_create_lock (&acpi_gbl_gpe_lock);
  87         if (ACPI_FAILURE (status)) {
  88                 return_ACPI_STATUS (status);
  89         }
  90
  91         status = acpi_os_create_lock (&acpi_gbl_hardware_lock);
  92         if (ACPI_FAILURE (status)) {
  93                 return_ACPI_STATUS (status);
  94         }
  95
  96         /* Mutex for _OSI support */
  97         status = acpi_os_create_mutex(&acpi_gbl_osi_mutex);
  98         if (ACPI_FAILURE(status)) {
  99                 return_ACPI_STATUS(status);
 100         }
 101
 102         /* Create the reader/writer lock for namespace access */
 103
 104         status = acpi_ut_create_rw_lock(&acpi_gbl_namespace_rw_lock);
 105         return_ACPI_STATUS(status);
 106 }
 107
 108 /*******************************************************************************
 109  *
 110  * FUNCTION:    acpi_ut_mutex_terminate
 111  *
 112  * PARAMETERS:  None.
 113  *
 114  * RETURN:      None.
 115  *
 116  * DESCRIPTION: Delete all of the system mutex objects. This includes mutexes,
 117  *              spin locks, and reader/writer locks.
 118  *
 119  ******************************************************************************/
 120
 121 void acpi_ut_mutex_terminate(void)
 122 {
 123         u32 i;
 124
 125         ACPI_FUNCTION_TRACE(ut_mutex_terminate);
 126
 127         /* Delete each predefined mutex object */
 128
 129         for (i = 0; i < ACPI_NUM_MUTEX; i++) {
 130                 acpi_ut_delete_mutex(i);
 131         }
 132
 133         acpi_os_delete_mutex(acpi_gbl_osi_mutex);
 134
 135         /* Delete the spinlocks */
 136
 137         acpi_os_delete_lock(acpi_gbl_gpe_lock);
 138         acpi_os_delete_lock(acpi_gbl_hardware_lock);
 139
 140         /* Delete the reader/writer lock */
 141
 142         acpi_ut_delete_rw_lock(&acpi_gbl_namespace_rw_lock);
 143         return_VOID;
 144 }
 145
 146 /*******************************************************************************
 147  *
 148  * FUNCTION:    acpi_ut_create_mutex
 149  *
 150  * PARAMETERS:  mutex_iD        - ID of the mutex to be created
 151  *
 152  * RETURN:      Status
 153  *
 154  * DESCRIPTION: Create a mutex object.
 155  *
 156  ******************************************************************************/
 157
 158 static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id)
 159 {
 160         acpi_status status = AE_OK;
 161
 162         ACPI_FUNCTION_TRACE_U32(ut_create_mutex, mutex_id);
 163
 164         if (!acpi_gbl_mutex_info[mutex_id].mutex) {
 165                 status =
 166                     acpi_os_create_mutex(&acpi_gbl_mutex_info[mutex_id].mutex);
 167                 acpi_gbl_mutex_info[mutex_id].thread_id =
 168                     ACPI_MUTEX_NOT_ACQUIRED;
 169                 acpi_gbl_mutex_info[mutex_id].use_count = 0;
 170         }
 171
 172         return_ACPI_STATUS(status);
 173 }
 174
 175 /*******************************************************************************
 176  *
 177  * FUNCTION:    acpi_ut_delete_mutex
 178  *
 179  * PARAMETERS:  mutex_iD        - ID of the mutex to be deleted
 180  *
 181  * RETURN:      Status
 182  *
 183  * DESCRIPTION: Delete a mutex object.
 184  *
 185  ******************************************************************************/
 186
 187 static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id)
 188 {
 189
 190         ACPI_FUNCTION_TRACE_U32(ut_delete_mutex, mutex_id);
 191
 192         acpi_os_delete_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
 193
 194         acpi_gbl_mutex_info[mutex_id].mutex = NULL;
 195         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
 196 }
 197
 198 /*******************************************************************************
 199  *
 200  * FUNCTION:    acpi_ut_acquire_mutex
 201  *
 202  * PARAMETERS:  mutex_iD        - ID of the mutex to be acquired
 203  *
 204  * RETURN:      Status
 205  *
 206  * DESCRIPTION: Acquire a mutex object.
 207  *
 208  ******************************************************************************/
 209
 210 acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
 211 {
 212         acpi_status status;
 213         acpi_thread_id this_thread_id;
 214
 215         ACPI_FUNCTION_NAME(ut_acquire_mutex);
 216
 217         if (mutex_id > ACPI_MAX_MUTEX) {
 218                 return (AE_BAD_PARAMETER);
 219         }
 220
 221         this_thread_id = acpi_os_get_thread_id();
 222
 223 #ifdef ACPI_MUTEX_DEBUG
 224         {
 225                 u32 i;
 226                 /*
 227                  * Mutex debug code, for internal debugging only.
 228                  *
 229                  * Deadlock prevention.  Check if this thread owns any mutexes of value
 230                  * greater than or equal to this one.  If so, the thread has violated
 231                  * the mutex ordering rule.  This indicates a coding error somewhere in
 232                  * the ACPI subsystem code.
 233                  */
 234                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
 235                         if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
 236                                 if (i == mutex_id) {
 237                                         ACPI_ERROR((AE_INFO,
 238                                                     "Mutex [%s] already acquired by this thread [%u]",
 239                                                     acpi_ut_get_mutex_name
 240                                                     (mutex_id),
 241                                                     (u32)this_thread_id));
 242
 243                                         return (AE_ALREADY_ACQUIRED);
 244                                 }
 245
 246                                 ACPI_ERROR((AE_INFO,
 247                                             "Invalid acquire order: Thread %u owns [%s], wants [%s]",
 248                                             (u32)this_thread_id,
 249                                             acpi_ut_get_mutex_name(i),
 250                                             acpi_ut_get_mutex_name(mutex_id)));
 251
 252                                 return (AE_ACQUIRE_DEADLOCK);
 253                         }
 254                 }
 255         }
 256 #endif
 257
 258         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
 259                           "Thread %u attempting to acquire Mutex [%s]\n",
 260                           (u32)this_thread_id,
 261                           acpi_ut_get_mutex_name(mutex_id)));
 262
 263         status = acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
 264                                        ACPI_WAIT_FOREVER);
 265         if (ACPI_SUCCESS(status)) {
 266                 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
 267                                   "Thread %u acquired Mutex [%s]\n",
 268                                   (u32)this_thread_id,
 269                                   acpi_ut_get_mutex_name(mutex_id)));
 270
 271                 acpi_gbl_mutex_info[mutex_id].use_count++;
 272                 acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
 273         } else {
 274                 ACPI_EXCEPTION((AE_INFO, status,
 275                                 "Thread %u could not acquire Mutex [0x%X]",
 276                                 (u32)this_thread_id, mutex_id));
 277         }
 278
 279         return (status);
 280 }
 281
 282 /*******************************************************************************
 283  *
 284  * FUNCTION:    acpi_ut_release_mutex
 285  *
 286  * PARAMETERS:  mutex_iD        - ID of the mutex to be released
 287  *
 288  * RETURN:      Status
 289  *
 290  * DESCRIPTION: Release a mutex object.
 291  *
 292  ******************************************************************************/
 293
 294 acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
 295 {
 296         acpi_thread_id this_thread_id;
 297
 298         ACPI_FUNCTION_NAME(ut_release_mutex);
 299
 300         this_thread_id = acpi_os_get_thread_id();
 301
 302         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
 303                           (u32)this_thread_id,
 304                           acpi_ut_get_mutex_name(mutex_id)));
 305
 306         if (mutex_id > ACPI_MAX_MUTEX) {
 307                 return (AE_BAD_PARAMETER);
 308         }
 309
 310         /*
 311          * Mutex must be acquired in order to release it!
 312          */
 313         if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
 314                 ACPI_ERROR((AE_INFO,
 315                             "Mutex [0x%X] is not acquired, cannot release",
 316                             mutex_id));
 317
 318                 return (AE_NOT_ACQUIRED);
 319         }
 320 #ifdef ACPI_MUTEX_DEBUG
 321         {
 322                 u32 i;
 323                 /*
 324                  * Mutex debug code, for internal debugging only.
 325                  *
 326                  * Deadlock prevention.  Check if this thread owns any mutexes of value
 327                  * greater than this one.  If so, the thread has violated the mutex
 328                  * ordering rule.  This indicates a coding error somewhere in
 329                  * the ACPI subsystem code.
 330                  */
 331                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
 332                         if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
 333                                 if (i == mutex_id) {
 334                                         continue;
 335                                 }
 336
 337                                 ACPI_ERROR((AE_INFO,
 338                                             "Invalid release order: owns [%s], releasing [%s]",
 339                                             acpi_ut_get_mutex_name(i),
 340                                             acpi_ut_get_mutex_name(mutex_id)));
 341
 342                                 return (AE_RELEASE_DEADLOCK);
 343                         }
 344                 }
 345         }
 346 #endif
 347
 348         /* Mark unlocked FIRST */
 349
 350         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
 351
 352         acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
 353         return (AE_OK);
 354 }