1 2 /****************************************************************************** 3 * 4 * Module Name: exmutex - ASL Mutex Acquire/Release functions 5 * 6 *****************************************************************************/ 7 8 /* 9 * Copyright (C) 2000 - 2008, Intel Corp. 10 * All rights reserved. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions, and the following disclaimer, 17 * without modification. 18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 19 * substantially similar to the "NO WARRANTY" disclaimer below 20 * ("Disclaimer") and any redistribution must be conditioned upon 21 * including a substantially similar Disclaimer requirement for further 22 * binary redistribution. 23 * 3. Neither the names of the above-listed copyright holders nor the names 24 * of any contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * Alternatively, this software may be distributed under the terms of the 28 * GNU General Public License ("GPL") version 2 as published by the Free 29 * Software Foundation. 30 * 31 * NO WARRANTY 32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR 35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 42 * POSSIBILITY OF SUCH DAMAGES. 43 */ 44 45 #include <acpi/acpi.h> 46 #include "accommon.h" 47 #include "acinterp.h" 48 #include "acevents.h" 49 50 #define _COMPONENT ACPI_EXECUTER 51 ACPI_MODULE_NAME("exmutex") 52 53 /* Local prototypes */ 54 static void 55 acpi_ex_link_mutex(union acpi_operand_object *obj_desc, 56 struct acpi_thread_state *thread); 57 58 /******************************************************************************* 59 * 60 * FUNCTION: acpi_ex_unlink_mutex 61 * 62 * PARAMETERS: obj_desc - The mutex to be unlinked 63 * 64 * RETURN: None 65 * 66 * DESCRIPTION: Remove a mutex from the "AcquiredMutex" list 67 * 68 ******************************************************************************/ 69 70 void acpi_ex_unlink_mutex(union acpi_operand_object *obj_desc) 71 { 72 struct acpi_thread_state *thread = obj_desc->mutex.owner_thread; 73 74 if (!thread) { 75 return; 76 } 77 78 /* Doubly linked list */ 79 80 if (obj_desc->mutex.next) { 81 (obj_desc->mutex.next)->mutex.prev = obj_desc->mutex.prev; 82 } 83 84 if (obj_desc->mutex.prev) { 85 (obj_desc->mutex.prev)->mutex.next = obj_desc->mutex.next; 86 } else { 87 thread->acquired_mutex_list = obj_desc->mutex.next; 88 } 89 } 90 91 /******************************************************************************* 92 * 93 * FUNCTION: acpi_ex_link_mutex 94 * 95 * PARAMETERS: obj_desc - The mutex to be linked 96 * Thread - Current executing thread object 97 * 98 * RETURN: None 99 * 100 * DESCRIPTION: Add a mutex to the "AcquiredMutex" list for this walk 101 * 102 ******************************************************************************/ 103 104 static void 105 acpi_ex_link_mutex(union acpi_operand_object *obj_desc, 106 struct acpi_thread_state *thread) 107 { 108 union acpi_operand_object *list_head; 109 110 list_head = thread->acquired_mutex_list; 111 112 /* This object will be the first object in the list */ 113 114 obj_desc->mutex.prev = NULL; 115 obj_desc->mutex.next = list_head; 116 117 /* Update old first object to point back to this object */ 118 119 if (list_head) { 120 list_head->mutex.prev = obj_desc; 121 } 122 123 /* Update list head */ 124 125 thread->acquired_mutex_list = obj_desc; 126 } 127 128 /******************************************************************************* 129 * 130 * FUNCTION: acpi_ex_acquire_mutex_object 131 * 132 * PARAMETERS: time_desc - Timeout in milliseconds 133 * obj_desc - Mutex object 134 * Thread - Current thread state 135 * 136 * RETURN: Status 137 * 138 * DESCRIPTION: Acquire an AML mutex, low-level interface. Provides a common 139 * path that supports multiple acquires by the same thread. 140 * 141 * MUTEX: Interpreter must be locked 142 * 143 * NOTE: This interface is called from three places: 144 * 1) From acpi_ex_acquire_mutex, via an AML Acquire() operator 145 * 2) From acpi_ex_acquire_global_lock when an AML Field access requires the 146 * global lock 147 * 3) From the external interface, acpi_acquire_global_lock 148 * 149 ******************************************************************************/ 150 151 acpi_status 152 acpi_ex_acquire_mutex_object(u16 timeout, 153 union acpi_operand_object *obj_desc, 154 acpi_thread_id thread_id) 155 { 156 acpi_status status; 157 158 ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex_object, obj_desc); 159 160 if (!obj_desc) { 161 return_ACPI_STATUS(AE_BAD_PARAMETER); 162 } 163 164 /* Support for multiple acquires by the owning thread */ 165 166 if (obj_desc->mutex.thread_id == thread_id) { 167 /* 168 * The mutex is already owned by this thread, just increment the 169 * acquisition depth 170 */ 171 obj_desc->mutex.acquisition_depth++; 172 return_ACPI_STATUS(AE_OK); 173 } 174 175 /* Acquire the mutex, wait if necessary. Special case for Global Lock */ 176 177 if (obj_desc == acpi_gbl_global_lock_mutex) { 178 status = acpi_ev_acquire_global_lock(timeout); 179 } else { 180 status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex, 181 timeout); 182 } 183 184 if (ACPI_FAILURE(status)) { 185 186 /* Includes failure from a timeout on time_desc */ 187 188 return_ACPI_STATUS(status); 189 } 190 191 /* Acquired the mutex: update mutex object */ 192 193 obj_desc->mutex.thread_id = thread_id; 194 obj_desc->mutex.acquisition_depth = 1; 195 obj_desc->mutex.original_sync_level = 0; 196 obj_desc->mutex.owner_thread = NULL; /* Used only for AML Acquire() */ 197 198 return_ACPI_STATUS(AE_OK); 199 } 200 201 /******************************************************************************* 202 * 203 * FUNCTION: acpi_ex_acquire_mutex 204 * 205 * PARAMETERS: time_desc - Timeout integer 206 * obj_desc - Mutex object 207 * walk_state - Current method execution state 208 * 209 * RETURN: Status 210 * 211 * DESCRIPTION: Acquire an AML mutex 212 * 213 ******************************************************************************/ 214 215 acpi_status 216 acpi_ex_acquire_mutex(union acpi_operand_object *time_desc, 217 union acpi_operand_object *obj_desc, 218 struct acpi_walk_state *walk_state) 219 { 220 acpi_status status; 221 222 ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex, obj_desc); 223 224 if (!obj_desc) { 225 return_ACPI_STATUS(AE_BAD_PARAMETER); 226 } 227 228 /* Must have a valid thread ID */ 229 230 if (!walk_state->thread) { 231 ACPI_ERROR((AE_INFO, 232 "Cannot acquire Mutex [%4.4s], null thread info", 233 acpi_ut_get_node_name(obj_desc->mutex.node))); 234 return_ACPI_STATUS(AE_AML_INTERNAL); 235 } 236 237 /* 238 * Current sync level must be less than or equal to the sync level of the 239 * mutex. This mechanism provides some deadlock prevention 240 */ 241 if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) { 242 ACPI_ERROR((AE_INFO, 243 "Cannot acquire Mutex [%4.4s], current SyncLevel is too large (%d)", 244 acpi_ut_get_node_name(obj_desc->mutex.node), 245 walk_state->thread->current_sync_level)); 246 return_ACPI_STATUS(AE_AML_MUTEX_ORDER); 247 } 248 249 status = acpi_ex_acquire_mutex_object((u16) time_desc->integer.value, 250 obj_desc, 251 walk_state->thread->thread_id); 252 if (ACPI_SUCCESS(status) && obj_desc->mutex.acquisition_depth == 1) { 253 254 /* Save Thread object, original/current sync levels */ 255 256 obj_desc->mutex.owner_thread = walk_state->thread; 257 obj_desc->mutex.original_sync_level = 258 walk_state->thread->current_sync_level; 259 walk_state->thread->current_sync_level = 260 obj_desc->mutex.sync_level; 261 262 /* Link the mutex to the current thread for force-unlock at method exit */ 263 264 acpi_ex_link_mutex(obj_desc, walk_state->thread); 265 } 266 267 return_ACPI_STATUS(status); 268 } 269 270 /******************************************************************************* 271 * 272 * FUNCTION: acpi_ex_release_mutex_object 273 * 274 * PARAMETERS: obj_desc - The object descriptor for this op 275 * 276 * RETURN: Status 277 * 278 * DESCRIPTION: Release a previously acquired Mutex, low level interface. 279 * Provides a common path that supports multiple releases (after 280 * previous multiple acquires) by the same thread. 281 * 282 * MUTEX: Interpreter must be locked 283 * 284 * NOTE: This interface is called from three places: 285 * 1) From acpi_ex_release_mutex, via an AML Acquire() operator 286 * 2) From acpi_ex_release_global_lock when an AML Field access requires the 287 * global lock 288 * 3) From the external interface, acpi_release_global_lock 289 * 290 ******************************************************************************/ 291 292 acpi_status acpi_ex_release_mutex_object(union acpi_operand_object *obj_desc) 293 { 294 acpi_status status = AE_OK; 295 296 ACPI_FUNCTION_TRACE(ex_release_mutex_object); 297 298 if (obj_desc->mutex.acquisition_depth == 0) { 299 return (AE_NOT_ACQUIRED); 300 } 301 302 /* Match multiple Acquires with multiple Releases */ 303 304 obj_desc->mutex.acquisition_depth--; 305 if (obj_desc->mutex.acquisition_depth != 0) { 306 307 /* Just decrement the depth and return */ 308 309 return_ACPI_STATUS(AE_OK); 310 } 311 312 if (obj_desc->mutex.owner_thread) { 313 314 /* Unlink the mutex from the owner's list */ 315 316 acpi_ex_unlink_mutex(obj_desc); 317 obj_desc->mutex.owner_thread = NULL; 318 } 319 320 /* Release the mutex, special case for Global Lock */ 321 322 if (obj_desc == acpi_gbl_global_lock_mutex) { 323 status = acpi_ev_release_global_lock(); 324 } else { 325 acpi_os_release_mutex(obj_desc->mutex.os_mutex); 326 } 327 328 /* Clear mutex info */ 329 330 obj_desc->mutex.thread_id = NULL; 331 return_ACPI_STATUS(status); 332 } 333 334 /******************************************************************************* 335 * 336 * FUNCTION: acpi_ex_release_mutex 337 * 338 * PARAMETERS: obj_desc - The object descriptor for this op 339 * walk_state - Current method execution state 340 * 341 * RETURN: Status 342 * 343 * DESCRIPTION: Release a previously acquired Mutex. 344 * 345 ******************************************************************************/ 346 347 acpi_status 348 acpi_ex_release_mutex(union acpi_operand_object *obj_desc, 349 struct acpi_walk_state *walk_state) 350 { 351 acpi_status status = AE_OK; 352 353 ACPI_FUNCTION_TRACE(ex_release_mutex); 354 355 if (!obj_desc) { 356 return_ACPI_STATUS(AE_BAD_PARAMETER); 357 } 358 359 /* The mutex must have been previously acquired in order to release it */ 360 361 if (!obj_desc->mutex.owner_thread) { 362 ACPI_ERROR((AE_INFO, 363 "Cannot release Mutex [%4.4s], not acquired", 364 acpi_ut_get_node_name(obj_desc->mutex.node))); 365 return_ACPI_STATUS(AE_AML_MUTEX_NOT_ACQUIRED); 366 } 367 368 /* 369 * The Mutex is owned, but this thread must be the owner. 370 * Special case for Global Lock, any thread can release 371 */ 372 if ((obj_desc->mutex.owner_thread->thread_id != 373 walk_state->thread->thread_id) 374 && (obj_desc != acpi_gbl_global_lock_mutex)) { 375 ACPI_ERROR((AE_INFO, 376 "Thread %lX cannot release Mutex [%4.4s] acquired by thread %lX", 377 (unsigned long)walk_state->thread->thread_id, 378 acpi_ut_get_node_name(obj_desc->mutex.node), 379 (unsigned long)obj_desc->mutex.owner_thread-> 380 thread_id)); 381 return_ACPI_STATUS(AE_AML_NOT_OWNER); 382 } 383 384 /* Must have a valid thread ID */ 385 386 if (!walk_state->thread) { 387 ACPI_ERROR((AE_INFO, 388 "Cannot release Mutex [%4.4s], null thread info", 389 acpi_ut_get_node_name(obj_desc->mutex.node))); 390 return_ACPI_STATUS(AE_AML_INTERNAL); 391 } 392 393 /* 394 * The sync level of the mutex must be less than or equal to the current 395 * sync level 396 */ 397 if (obj_desc->mutex.sync_level > walk_state->thread->current_sync_level) { 398 ACPI_ERROR((AE_INFO, 399 "Cannot release Mutex [%4.4s], SyncLevel mismatch: mutex %d current %d", 400 acpi_ut_get_node_name(obj_desc->mutex.node), 401 obj_desc->mutex.sync_level, 402 walk_state->thread->current_sync_level)); 403 return_ACPI_STATUS(AE_AML_MUTEX_ORDER); 404 } 405 406 status = acpi_ex_release_mutex_object(obj_desc); 407 408 if (obj_desc->mutex.acquisition_depth == 0) { 409 410 /* Restore the original sync_level */ 411 412 walk_state->thread->current_sync_level = 413 obj_desc->mutex.original_sync_level; 414 } 415 return_ACPI_STATUS(status); 416 } 417 418 /******************************************************************************* 419 * 420 * FUNCTION: acpi_ex_release_all_mutexes 421 * 422 * PARAMETERS: Thread - Current executing thread object 423 * 424 * RETURN: Status 425 * 426 * DESCRIPTION: Release all mutexes held by this thread 427 * 428 * NOTE: This function is called as the thread is exiting the interpreter. 429 * Mutexes are not released when an individual control method is exited, but 430 * only when the parent thread actually exits the interpreter. This allows one 431 * method to acquire a mutex, and a different method to release it, as long as 432 * this is performed underneath a single parent control method. 433 * 434 ******************************************************************************/ 435 436 void acpi_ex_release_all_mutexes(struct acpi_thread_state *thread) 437 { 438 union acpi_operand_object *next = thread->acquired_mutex_list; 439 union acpi_operand_object *obj_desc; 440 441 ACPI_FUNCTION_ENTRY(); 442 443 /* Traverse the list of owned mutexes, releasing each one */ 444 445 while (next) { 446 obj_desc = next; 447 next = obj_desc->mutex.next; 448 449 obj_desc->mutex.prev = NULL; 450 obj_desc->mutex.next = NULL; 451 obj_desc->mutex.acquisition_depth = 0; 452 453 /* Release the mutex, special case for Global Lock */ 454 455 if (obj_desc == acpi_gbl_global_lock_mutex) { 456 457 /* Ignore errors */ 458 459 (void)acpi_ev_release_global_lock(); 460 } else { 461 acpi_os_release_mutex(obj_desc->mutex.os_mutex); 462 } 463 464 /* Mark mutex unowned */ 465 466 obj_desc->mutex.owner_thread = NULL; 467 obj_desc->mutex.thread_id = NULL; 468 469 /* Update Thread sync_level (Last mutex is the important one) */ 470 471 thread->current_sync_level = 472 obj_desc->mutex.original_sync_level; 473 } 474 } 475