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