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/drivers/acpi/acpica/utmutex.c

http://github.com/mirrors/linux
C | 330 lines | 165 code | 63 blank | 102 comment | 24 complexity | 86676040cffc32b122bc6a62e719d26e MD5 | raw file
  1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
  2/*******************************************************************************
  3 *
  4 * Module Name: utmutex - local mutex support
  5 *
  6 ******************************************************************************/
  7
  8#include <acpi/acpi.h>
  9#include "accommon.h"
 10
 11#define _COMPONENT          ACPI_UTILITIES
 12ACPI_MODULE_NAME("utmutex")
 13
 14/* Local prototypes */
 15static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id);
 16
 17static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id);
 18
 19/*******************************************************************************
 20 *
 21 * FUNCTION:    acpi_ut_mutex_initialize
 22 *
 23 * PARAMETERS:  None.
 24 *
 25 * RETURN:      Status
 26 *
 27 * DESCRIPTION: Create the system mutex objects. This includes mutexes,
 28 *              spin locks, and reader/writer locks.
 29 *
 30 ******************************************************************************/
 31
 32acpi_status acpi_ut_mutex_initialize(void)
 33{
 34	u32 i;
 35	acpi_status status;
 36
 37	ACPI_FUNCTION_TRACE(ut_mutex_initialize);
 38
 39	/* Create each of the predefined mutex objects */
 40
 41	for (i = 0; i < ACPI_NUM_MUTEX; i++) {
 42		status = acpi_ut_create_mutex(i);
 43		if (ACPI_FAILURE(status)) {
 44			return_ACPI_STATUS(status);
 45		}
 46	}
 47
 48	/* Create the spinlocks for use at interrupt level or for speed */
 49
 50	status = acpi_os_create_lock (&acpi_gbl_gpe_lock);
 51	if (ACPI_FAILURE (status)) {
 52		return_ACPI_STATUS (status);
 53	}
 54
 55	status = acpi_os_create_raw_lock(&acpi_gbl_hardware_lock);
 56	if (ACPI_FAILURE (status)) {
 57		return_ACPI_STATUS (status);
 58	}
 59
 60	status = acpi_os_create_lock(&acpi_gbl_reference_count_lock);
 61	if (ACPI_FAILURE(status)) {
 62		return_ACPI_STATUS(status);
 63	}
 64
 65	/* Mutex for _OSI support */
 66
 67	status = acpi_os_create_mutex(&acpi_gbl_osi_mutex);
 68	if (ACPI_FAILURE(status)) {
 69		return_ACPI_STATUS(status);
 70	}
 71
 72	/* Create the reader/writer lock for namespace access */
 73
 74	status = acpi_ut_create_rw_lock(&acpi_gbl_namespace_rw_lock);
 75	if (ACPI_FAILURE(status)) {
 76		return_ACPI_STATUS(status);
 77	}
 78
 79	return_ACPI_STATUS(status);
 80}
 81
 82/*******************************************************************************
 83 *
 84 * FUNCTION:    acpi_ut_mutex_terminate
 85 *
 86 * PARAMETERS:  None.
 87 *
 88 * RETURN:      None.
 89 *
 90 * DESCRIPTION: Delete all of the system mutex objects. This includes mutexes,
 91 *              spin locks, and reader/writer locks.
 92 *
 93 ******************************************************************************/
 94
 95void acpi_ut_mutex_terminate(void)
 96{
 97	u32 i;
 98
 99	ACPI_FUNCTION_TRACE(ut_mutex_terminate);
100
101	/* Delete each predefined mutex object */
102
103	for (i = 0; i < ACPI_NUM_MUTEX; i++) {
104		acpi_ut_delete_mutex(i);
105	}
106
107	acpi_os_delete_mutex(acpi_gbl_osi_mutex);
108
109	/* Delete the spinlocks */
110
111	acpi_os_delete_lock(acpi_gbl_gpe_lock);
112	acpi_os_delete_raw_lock(acpi_gbl_hardware_lock);
113	acpi_os_delete_lock(acpi_gbl_reference_count_lock);
114
115	/* Delete the reader/writer lock */
116
117	acpi_ut_delete_rw_lock(&acpi_gbl_namespace_rw_lock);
118	return_VOID;
119}
120
121/*******************************************************************************
122 *
123 * FUNCTION:    acpi_ut_create_mutex
124 *
125 * PARAMETERS:  mutex_ID        - ID of the mutex to be created
126 *
127 * RETURN:      Status
128 *
129 * DESCRIPTION: Create a mutex object.
130 *
131 ******************************************************************************/
132
133static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id)
134{
135	acpi_status status = AE_OK;
136
137	ACPI_FUNCTION_TRACE_U32(ut_create_mutex, mutex_id);
138
139	if (!acpi_gbl_mutex_info[mutex_id].mutex) {
140		status =
141		    acpi_os_create_mutex(&acpi_gbl_mutex_info[mutex_id].mutex);
142		acpi_gbl_mutex_info[mutex_id].thread_id =
143		    ACPI_MUTEX_NOT_ACQUIRED;
144		acpi_gbl_mutex_info[mutex_id].use_count = 0;
145	}
146
147	return_ACPI_STATUS(status);
148}
149
150/*******************************************************************************
151 *
152 * FUNCTION:    acpi_ut_delete_mutex
153 *
154 * PARAMETERS:  mutex_ID        - ID of the mutex to be deleted
155 *
156 * RETURN:      Status
157 *
158 * DESCRIPTION: Delete a mutex object.
159 *
160 ******************************************************************************/
161
162static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id)
163{
164
165	ACPI_FUNCTION_TRACE_U32(ut_delete_mutex, mutex_id);
166
167	acpi_os_delete_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
168
169	acpi_gbl_mutex_info[mutex_id].mutex = NULL;
170	acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
171
172	return_VOID;
173}
174
175/*******************************************************************************
176 *
177 * FUNCTION:    acpi_ut_acquire_mutex
178 *
179 * PARAMETERS:  mutex_ID        - ID of the mutex to be acquired
180 *
181 * RETURN:      Status
182 *
183 * DESCRIPTION: Acquire a mutex object.
184 *
185 ******************************************************************************/
186
187acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
188{
189	acpi_status status;
190	acpi_thread_id this_thread_id;
191
192	ACPI_FUNCTION_NAME(ut_acquire_mutex);
193
194	if (mutex_id > ACPI_MAX_MUTEX) {
195		return (AE_BAD_PARAMETER);
196	}
197
198	this_thread_id = acpi_os_get_thread_id();
199
200#ifdef ACPI_MUTEX_DEBUG
201	{
202		u32 i;
203		/*
204		 * Mutex debug code, for internal debugging only.
205		 *
206		 * Deadlock prevention. Check if this thread owns any mutexes of value
207		 * greater than or equal to this one. If so, the thread has violated
208		 * the mutex ordering rule. This indicates a coding error somewhere in
209		 * the ACPI subsystem code.
210		 */
211		for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
212			if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
213				if (i == mutex_id) {
214					ACPI_ERROR((AE_INFO,
215						    "Mutex [%s] already acquired by this thread [%u]",
216						    acpi_ut_get_mutex_name
217						    (mutex_id),
218						    (u32)this_thread_id));
219
220					return (AE_ALREADY_ACQUIRED);
221				}
222
223				ACPI_ERROR((AE_INFO,
224					    "Invalid acquire order: Thread %u owns [%s], wants [%s]",
225					    (u32)this_thread_id,
226					    acpi_ut_get_mutex_name(i),
227					    acpi_ut_get_mutex_name(mutex_id)));
228
229				return (AE_ACQUIRE_DEADLOCK);
230			}
231		}
232	}
233#endif
234
235	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
236			  "Thread %u attempting to acquire Mutex [%s]\n",
237			  (u32)this_thread_id,
238			  acpi_ut_get_mutex_name(mutex_id)));
239
240	status =
241	    acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
242				  ACPI_WAIT_FOREVER);
243	if (ACPI_SUCCESS(status)) {
244		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
245				  "Thread %u acquired Mutex [%s]\n",
246				  (u32)this_thread_id,
247				  acpi_ut_get_mutex_name(mutex_id)));
248
249		acpi_gbl_mutex_info[mutex_id].use_count++;
250		acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
251	} else {
252		ACPI_EXCEPTION((AE_INFO, status,
253				"Thread %u could not acquire Mutex [%s] (0x%X)",
254				(u32)this_thread_id,
255				acpi_ut_get_mutex_name(mutex_id), mutex_id));
256	}
257
258	return (status);
259}
260
261/*******************************************************************************
262 *
263 * FUNCTION:    acpi_ut_release_mutex
264 *
265 * PARAMETERS:  mutex_ID        - ID of the mutex to be released
266 *
267 * RETURN:      Status
268 *
269 * DESCRIPTION: Release a mutex object.
270 *
271 ******************************************************************************/
272
273acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
274{
275	ACPI_FUNCTION_NAME(ut_release_mutex);
276
277	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
278			  (u32)acpi_os_get_thread_id(),
279			  acpi_ut_get_mutex_name(mutex_id)));
280
281	if (mutex_id > ACPI_MAX_MUTEX) {
282		return (AE_BAD_PARAMETER);
283	}
284
285	/*
286	 * Mutex must be acquired in order to release it!
287	 */
288	if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
289		ACPI_ERROR((AE_INFO,
290			    "Mutex [%s] (0x%X) is not acquired, cannot release",
291			    acpi_ut_get_mutex_name(mutex_id), mutex_id));
292
293		return (AE_NOT_ACQUIRED);
294	}
295#ifdef ACPI_MUTEX_DEBUG
296	{
297		u32 i;
298		/*
299		 * Mutex debug code, for internal debugging only.
300		 *
301		 * Deadlock prevention. Check if this thread owns any mutexes of value
302		 * greater than this one. If so, the thread has violated the mutex
303		 * ordering rule. This indicates a coding error somewhere in
304		 * the ACPI subsystem code.
305		 */
306		for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
307			if (acpi_gbl_mutex_info[i].thread_id ==
308			    acpi_os_get_thread_id()) {
309				if (i == mutex_id) {
310					continue;
311				}
312
313				ACPI_ERROR((AE_INFO,
314					    "Invalid release order: owns [%s], releasing [%s]",
315					    acpi_ut_get_mutex_name(i),
316					    acpi_ut_get_mutex_name(mutex_id)));
317
318				return (AE_RELEASE_DEADLOCK);
319			}
320		}
321	}
322#endif
323
324	/* Mark unlocked FIRST */
325
326	acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
327
328	acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
329	return (AE_OK);
330}