drivers/acpi/acpica/utmutex.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: utmutex - local mutex support
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2013, 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         return_VOID;
 198 }
 199
 200 /*******************************************************************************
 201  *
 202  * FUNCTION:    acpi_ut_acquire_mutex
 203  *
 204  * PARAMETERS:  mutex_ID        - ID of the mutex to be acquired
 205  *
 206  * RETURN:      Status
 207  *
 208  * DESCRIPTION: Acquire a mutex object.
 209  *
 210  ******************************************************************************/
 211
 212 acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
 213 {
 214         acpi_status status;
 215         acpi_thread_id this_thread_id;
 216
 217         ACPI_FUNCTION_NAME(ut_acquire_mutex);
 218
 219         if (mutex_id > ACPI_MAX_MUTEX) {
 220                 return (AE_BAD_PARAMETER);
 221         }
 222
 223         this_thread_id = acpi_os_get_thread_id();
 224
 225 #ifdef ACPI_MUTEX_DEBUG
 226         {
 227                 u32 i;
 228                 /*
 229                  * Mutex debug code, for internal debugging only.
 230                  *
 231                  * Deadlock prevention. Check if this thread owns any mutexes of value
 232                  * greater than or equal to this one. If so, the thread has violated
 233                  * the mutex ordering rule. This indicates a coding error somewhere in
 234                  * the ACPI subsystem code.
 235                  */
 236                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
 237                         if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
 238                                 if (i == mutex_id) {
 239                                         ACPI_ERROR((AE_INFO,
 240                                                     "Mutex [%s] already acquired by this thread [%u]",
 241                                                     acpi_ut_get_mutex_name
 242                                                     (mutex_id),
 243                                                     (u32)this_thread_id));
 244
 245                                         return (AE_ALREADY_ACQUIRED);
 246                                 }
 247
 248                                 ACPI_ERROR((AE_INFO,
 249                                             "Invalid acquire order: Thread %u owns [%s], wants [%s]",
 250                                             (u32)this_thread_id,
 251                                             acpi_ut_get_mutex_name(i),
 252                                             acpi_ut_get_mutex_name(mutex_id)));
 253
 254                                 return (AE_ACQUIRE_DEADLOCK);
 255                         }
 256                 }
 257         }
 258 #endif
 259
 260         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
 261                           "Thread %u attempting to acquire Mutex [%s]\n",
 262                           (u32)this_thread_id,
 263                           acpi_ut_get_mutex_name(mutex_id)));
 264
 265         status = acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
 266                                        ACPI_WAIT_FOREVER);
 267         if (ACPI_SUCCESS(status)) {
 268                 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
 269                                   "Thread %u acquired Mutex [%s]\n",
 270                                   (u32)this_thread_id,
 271                                   acpi_ut_get_mutex_name(mutex_id)));
 272
 273                 acpi_gbl_mutex_info[mutex_id].use_count++;
 274                 acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
 275         } else {
 276                 ACPI_EXCEPTION((AE_INFO, status,
 277                                 "Thread %u could not acquire Mutex [0x%X]",
 278                                 (u32)this_thread_id, mutex_id));
 279         }
 280
 281         return (status);
 282 }
 283
 284 /*******************************************************************************
 285  *
 286  * FUNCTION:    acpi_ut_release_mutex
 287  *
 288  * PARAMETERS:  mutex_ID        - ID of the mutex to be released
 289  *
 290  * RETURN:      Status
 291  *
 292  * DESCRIPTION: Release a mutex object.
 293  *
 294  ******************************************************************************/
 295
 296 acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
 297 {
 298         ACPI_FUNCTION_NAME(ut_release_mutex);
 299
 300         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
 301                           (u32)acpi_os_get_thread_id(),
 302                           acpi_ut_get_mutex_name(mutex_id)));
 303
 304         if (mutex_id > ACPI_MAX_MUTEX) {
 305                 return (AE_BAD_PARAMETER);
 306         }
 307
 308         /*
 309          * Mutex must be acquired in order to release it!
 310          */
 311         if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
 312                 ACPI_ERROR((AE_INFO,
 313                             "Mutex [0x%X] is not acquired, cannot release",
 314                             mutex_id));
 315
 316                 return (AE_NOT_ACQUIRED);
 317         }
 318 #ifdef ACPI_MUTEX_DEBUG
 319         {
 320                 u32 i;
 321                 /*
 322                  * Mutex debug code, for internal debugging only.
 323                  *
 324                  * Deadlock prevention. Check if this thread owns any mutexes of value
 325                  * greater than this one. If so, the thread has violated the mutex
 326                  * ordering rule. This indicates a coding error somewhere in
 327                  * the ACPI subsystem code.
 328                  */
 329                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
 330                         if (acpi_gbl_mutex_info[i].thread_id ==
 331                             acpi_os_get_thread_id()) {
 332                                 if (i == mutex_id) {
 333                                         continue;
 334                                 }
 335
 336                                 ACPI_ERROR((AE_INFO,
 337                                             "Invalid release order: owns [%s], releasing [%s]",
 338                                             acpi_ut_get_mutex_name(i),
 339                                             acpi_ut_get_mutex_name(mutex_id)));
 340
 341                                 return (AE_RELEASE_DEADLOCK);
 342                         }
 343                 }
 344         }
 345 #endif
 346
 347         /* Mark unlocked FIRST */
 348
 349         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
 350
 351         acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
 352         return (AE_OK);
 353 }