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 or for speed */
  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         status = acpi_os_create_lock(&acpi_gbl_reference_count_lock);
  97         if (ACPI_FAILURE(status)) {
  98                 return_ACPI_STATUS(status);
  99         }
 100
 101         /* Mutex for _OSI support */
 102
 103         status = acpi_os_create_mutex(&acpi_gbl_osi_mutex);
 104         if (ACPI_FAILURE(status)) {
 105                 return_ACPI_STATUS(status);
 106         }
 107
 108         /* Create the reader/writer lock for namespace access */
 109
 110         status = acpi_ut_create_rw_lock(&acpi_gbl_namespace_rw_lock);
 111         return_ACPI_STATUS(status);
 112 }
 113
 114 /*******************************************************************************
 115  *
 116  * FUNCTION:    acpi_ut_mutex_terminate
 117  *
 118  * PARAMETERS:  None.
 119  *
 120  * RETURN:      None.
 121  *
 122  * DESCRIPTION: Delete all of the system mutex objects. This includes mutexes,
 123  *              spin locks, and reader/writer locks.
 124  *
 125  ******************************************************************************/
 126
 127 void acpi_ut_mutex_terminate(void)
 128 {
 129         u32 i;
 130
 131         ACPI_FUNCTION_TRACE(ut_mutex_terminate);
 132
 133         /* Delete each predefined mutex object */
 134
 135         for (i = 0; i < ACPI_NUM_MUTEX; i++) {
 136                 acpi_ut_delete_mutex(i);
 137         }
 138
 139         acpi_os_delete_mutex(acpi_gbl_osi_mutex);
 140
 141         /* Delete the spinlocks */
 142
 143         acpi_os_delete_lock(acpi_gbl_gpe_lock);
 144         acpi_os_delete_lock(acpi_gbl_hardware_lock);
 145         acpi_os_delete_lock(acpi_gbl_reference_count_lock);
 146
 147         /* Delete the reader/writer lock */
 148
 149         acpi_ut_delete_rw_lock(&acpi_gbl_namespace_rw_lock);
 150         return_VOID;
 151 }
 152
 153 /*******************************************************************************
 154  *
 155  * FUNCTION:    acpi_ut_create_mutex
 156  *
 157  * PARAMETERS:  mutex_ID        - ID of the mutex to be created
 158  *
 159  * RETURN:      Status
 160  *
 161  * DESCRIPTION: Create a mutex object.
 162  *
 163  ******************************************************************************/
 164
 165 static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id)
 166 {
 167         acpi_status status = AE_OK;
 168
 169         ACPI_FUNCTION_TRACE_U32(ut_create_mutex, mutex_id);
 170
 171         if (!acpi_gbl_mutex_info[mutex_id].mutex) {
 172                 status =
 173                     acpi_os_create_mutex(&acpi_gbl_mutex_info[mutex_id].mutex);
 174                 acpi_gbl_mutex_info[mutex_id].thread_id =
 175                     ACPI_MUTEX_NOT_ACQUIRED;
 176                 acpi_gbl_mutex_info[mutex_id].use_count = 0;
 177         }
 178
 179         return_ACPI_STATUS(status);
 180 }
 181
 182 /*******************************************************************************
 183  *
 184  * FUNCTION:    acpi_ut_delete_mutex
 185  *
 186  * PARAMETERS:  mutex_ID        - ID of the mutex to be deleted
 187  *
 188  * RETURN:      Status
 189  *
 190  * DESCRIPTION: Delete a mutex object.
 191  *
 192  ******************************************************************************/
 193
 194 static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id)
 195 {
 196
 197         ACPI_FUNCTION_TRACE_U32(ut_delete_mutex, mutex_id);
 198
 199         acpi_os_delete_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
 200
 201         acpi_gbl_mutex_info[mutex_id].mutex = NULL;
 202         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
 203
 204         return_VOID;
 205 }
 206
 207 /*******************************************************************************
 208  *
 209  * FUNCTION:    acpi_ut_acquire_mutex
 210  *
 211  * PARAMETERS:  mutex_ID        - ID of the mutex to be acquired
 212  *
 213  * RETURN:      Status
 214  *
 215  * DESCRIPTION: Acquire a mutex object.
 216  *
 217  ******************************************************************************/
 218
 219 acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
 220 {
 221         acpi_status status;
 222         acpi_thread_id this_thread_id;
 223
 224         ACPI_FUNCTION_NAME(ut_acquire_mutex);
 225
 226         if (mutex_id > ACPI_MAX_MUTEX) {
 227                 return (AE_BAD_PARAMETER);
 228         }
 229
 230         this_thread_id = acpi_os_get_thread_id();
 231
 232 #ifdef ACPI_MUTEX_DEBUG
 233         {
 234                 u32 i;
 235                 /*
 236                  * Mutex debug code, for internal debugging only.
 237                  *
 238                  * Deadlock prevention. Check if this thread owns any mutexes of value
 239                  * greater than or equal to this one. If so, the thread has violated
 240                  * the mutex ordering rule. This indicates a coding error somewhere in
 241                  * the ACPI subsystem code.
 242                  */
 243                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
 244                         if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
 245                                 if (i == mutex_id) {
 246                                         ACPI_ERROR((AE_INFO,
 247                                                     "Mutex [%s] already acquired by this thread [%u]",
 248                                                     acpi_ut_get_mutex_name
 249                                                     (mutex_id),
 250                                                     (u32)this_thread_id));
 251
 252                                         return (AE_ALREADY_ACQUIRED);
 253                                 }
 254
 255                                 ACPI_ERROR((AE_INFO,
 256                                             "Invalid acquire order: Thread %u owns [%s], wants [%s]",
 257                                             (u32)this_thread_id,
 258                                             acpi_ut_get_mutex_name(i),
 259                                             acpi_ut_get_mutex_name(mutex_id)));
 260
 261                                 return (AE_ACQUIRE_DEADLOCK);
 262                         }
 263                 }
 264         }
 265 #endif
 266
 267         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
 268                           "Thread %u attempting to acquire Mutex [%s]\n",
 269                           (u32)this_thread_id,
 270                           acpi_ut_get_mutex_name(mutex_id)));
 271
 272         status = acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
 273                                        ACPI_WAIT_FOREVER);
 274         if (ACPI_SUCCESS(status)) {
 275                 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
 276                                   "Thread %u acquired Mutex [%s]\n",
 277                                   (u32)this_thread_id,
 278                                   acpi_ut_get_mutex_name(mutex_id)));
 279
 280                 acpi_gbl_mutex_info[mutex_id].use_count++;
 281                 acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
 282         } else {
 283                 ACPI_EXCEPTION((AE_INFO, status,
 284                                 "Thread %u could not acquire Mutex [0x%X]",
 285                                 (u32)this_thread_id, mutex_id));
 286         }
 287
 288         return (status);
 289 }
 290
 291 /*******************************************************************************
 292  *
 293  * FUNCTION:    acpi_ut_release_mutex
 294  *
 295  * PARAMETERS:  mutex_ID        - ID of the mutex to be released
 296  *
 297  * RETURN:      Status
 298  *
 299  * DESCRIPTION: Release a mutex object.
 300  *
 301  ******************************************************************************/
 302
 303 acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
 304 {
 305         ACPI_FUNCTION_NAME(ut_release_mutex);
 306
 307         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
 308                           (u32)acpi_os_get_thread_id(),
 309                           acpi_ut_get_mutex_name(mutex_id)));
 310
 311         if (mutex_id > ACPI_MAX_MUTEX) {
 312                 return (AE_BAD_PARAMETER);
 313         }
 314
 315         /*
 316          * Mutex must be acquired in order to release it!
 317          */
 318         if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
 319                 ACPI_ERROR((AE_INFO,
 320                             "Mutex [0x%X] is not acquired, cannot release",
 321                             mutex_id));
 322
 323                 return (AE_NOT_ACQUIRED);
 324         }
 325 #ifdef ACPI_MUTEX_DEBUG
 326         {
 327                 u32 i;
 328                 /*
 329                  * Mutex debug code, for internal debugging only.
 330                  *
 331                  * Deadlock prevention. Check if this thread owns any mutexes of value
 332                  * greater than this one. If so, the thread has violated the mutex
 333                  * ordering rule. This indicates a coding error somewhere in
 334                  * the ACPI subsystem code.
 335                  */
 336                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
 337                         if (acpi_gbl_mutex_info[i].thread_id ==
 338                             acpi_os_get_thread_id()) {
 339                                 if (i == mutex_id) {
 340                                         continue;
 341                                 }
 342
 343                                 ACPI_ERROR((AE_INFO,
 344                                             "Invalid release order: owns [%s], releasing [%s]",
 345                                             acpi_ut_get_mutex_name(i),
 346                                             acpi_ut_get_mutex_name(mutex_id)));
 347
 348                                 return (AE_RELEASE_DEADLOCK);
 349                         }
 350                 }
 351         }
 352 #endif
 353
 354         /* Mark unlocked FIRST */
 355
 356         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
 357
 358         acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
 359         return (AE_OK);
 360 }