1 files changed, 502 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/exmutex.c b/drivers/acpi/acpica/exmutex.c
new file mode 100644
index 000000000..472030f2b
--- /dev/null
+++ b/drivers/acpi/acpica/exmutex.c
@@ -0,0 +1,502 @@
+/******************************************************************************
+ *
+ * Module Name: exmutex - ASL Mutex Acquire/Release functions
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2015, Intel Corp.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ *    of any contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ */
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acinterp.h"
+#include "acevents.h"
+
+#define _COMPONENT          ACPI_EXECUTER
+ACPI_MODULE_NAME("exmutex")
+
+/* Local prototypes */
+static void
+acpi_ex_link_mutex(union acpi_operand_object *obj_desc,
+		   struct acpi_thread_state *thread);
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_unlink_mutex
+ *
+ * PARAMETERS:  obj_desc            - The mutex to be unlinked
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Remove a mutex from the "AcquiredMutex" list
+ *
+ ******************************************************************************/
+
+void acpi_ex_unlink_mutex(union acpi_operand_object *obj_desc)
+{
+	struct acpi_thread_state *thread = obj_desc->mutex.owner_thread;
+
+	if (!thread) {
+		return;
+	}
+
+	/* Doubly linked list */
+
+	if (obj_desc->mutex.next) {
+		(obj_desc->mutex.next)->mutex.prev = obj_desc->mutex.prev;
+	}
+
+	if (obj_desc->mutex.prev) {
+		(obj_desc->mutex.prev)->mutex.next = obj_desc->mutex.next;
+
+		/*
+		 * Migrate the previous sync level associated with this mutex to
+		 * the previous mutex on the list so that it may be preserved.
+		 * This handles the case where several mutexes have been acquired
+		 * at the same level, but are not released in opposite order.
+		 */
+		(obj_desc->mutex.prev)->mutex.original_sync_level =
+		    obj_desc->mutex.original_sync_level;
+	} else {
+		thread->acquired_mutex_list = obj_desc->mutex.next;
+	}
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_link_mutex
+ *
+ * PARAMETERS:  obj_desc            - The mutex to be linked
+ *              thread              - Current executing thread object
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Add a mutex to the "AcquiredMutex" list for this walk
+ *
+ ******************************************************************************/
+
+static void
+acpi_ex_link_mutex(union acpi_operand_object *obj_desc,
+		   struct acpi_thread_state *thread)
+{
+	union acpi_operand_object *list_head;
+
+	list_head = thread->acquired_mutex_list;
+
+	/* This object will be the first object in the list */
+
+	obj_desc->mutex.prev = NULL;
+	obj_desc->mutex.next = list_head;
+
+	/* Update old first object to point back to this object */
+
+	if (list_head) {
+		list_head->mutex.prev = obj_desc;
+	}
+
+	/* Update list head */
+
+	thread->acquired_mutex_list = obj_desc;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_acquire_mutex_object
+ *
+ * PARAMETERS:  timeout             - Timeout in milliseconds
+ *              obj_desc            - Mutex object
+ *              thread_id           - Current thread state
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Acquire an AML mutex, low-level interface. Provides a common
+ *              path that supports multiple acquires by the same thread.
+ *
+ * MUTEX:       Interpreter must be locked
+ *
+ * NOTE: This interface is called from three places:
+ * 1) From acpi_ex_acquire_mutex, via an AML Acquire() operator
+ * 2) From acpi_ex_acquire_global_lock when an AML Field access requires the
+ *    global lock
+ * 3) From the external interface, acpi_acquire_global_lock
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_acquire_mutex_object(u16 timeout,
+			     union acpi_operand_object *obj_desc,
+			     acpi_thread_id thread_id)
+{
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex_object, obj_desc);
+
+	if (!obj_desc) {
+		return_ACPI_STATUS(AE_BAD_PARAMETER);
+	}
+
+	/* Support for multiple acquires by the owning thread */
+
+	if (obj_desc->mutex.thread_id == thread_id) {
+		/*
+		 * The mutex is already owned by this thread, just increment the
+		 * acquisition depth
+		 */
+		obj_desc->mutex.acquisition_depth++;
+		return_ACPI_STATUS(AE_OK);
+	}
+
+	/* Acquire the mutex, wait if necessary. Special case for Global Lock */
+
+	if (obj_desc == acpi_gbl_global_lock_mutex) {
+		status = acpi_ev_acquire_global_lock(timeout);
+	} else {
+		status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex,
+						   timeout);
+	}
+
+	if (ACPI_FAILURE(status)) {
+
+		/* Includes failure from a timeout on time_desc */
+
+		return_ACPI_STATUS(status);
+	}
+
+	/* Acquired the mutex: update mutex object */
+
+	obj_desc->mutex.thread_id = thread_id;
+	obj_desc->mutex.acquisition_depth = 1;
+	obj_desc->mutex.original_sync_level = 0;
+	obj_desc->mutex.owner_thread = NULL;	/* Used only for AML Acquire() */
+
+	return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_acquire_mutex
+ *
+ * PARAMETERS:  time_desc           - Timeout integer
+ *              obj_desc            - Mutex object
+ *              walk_state          - Current method execution state
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Acquire an AML mutex
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_acquire_mutex(union acpi_operand_object *time_desc,
+		      union acpi_operand_object *obj_desc,
+		      struct acpi_walk_state *walk_state)
+{
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex, obj_desc);
+
+	if (!obj_desc) {
+		return_ACPI_STATUS(AE_BAD_PARAMETER);
+	}
+
+	/* Must have a valid thread state struct */
+
+	if (!walk_state->thread) {
+		ACPI_ERROR((AE_INFO,
+			    "Cannot acquire Mutex [%4.4s], null thread info",
+			    acpi_ut_get_node_name(obj_desc->mutex.node)));
+		return_ACPI_STATUS(AE_AML_INTERNAL);
+	}
+
+	/*
+	 * Current sync level must be less than or equal to the sync level of the
+	 * mutex. This mechanism provides some deadlock prevention
+	 */
+	if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) {
+		ACPI_ERROR((AE_INFO,
+			    "Cannot acquire Mutex [%4.4s], current SyncLevel is too large (%u)",
+			    acpi_ut_get_node_name(obj_desc->mutex.node),
+			    walk_state->thread->current_sync_level));
+		return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
+	}
+
+	status = acpi_ex_acquire_mutex_object((u16) time_desc->integer.value,
+					      obj_desc,
+					      walk_state->thread->thread_id);
+	if (ACPI_SUCCESS(status) && obj_desc->mutex.acquisition_depth == 1) {
+
+		/* Save Thread object, original/current sync levels */
+
+		obj_desc->mutex.owner_thread = walk_state->thread;
+		obj_desc->mutex.original_sync_level =
+		    walk_state->thread->current_sync_level;
+		walk_state->thread->current_sync_level =
+		    obj_desc->mutex.sync_level;
+
+		/* Link the mutex to the current thread for force-unlock at method exit */
+
+		acpi_ex_link_mutex(obj_desc, walk_state->thread);
+	}
+
+	return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_release_mutex_object
+ *
+ * PARAMETERS:  obj_desc            - The object descriptor for this op
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Release a previously acquired Mutex, low level interface.
+ *              Provides a common path that supports multiple releases (after
+ *              previous multiple acquires) by the same thread.
+ *
+ * MUTEX:       Interpreter must be locked
+ *
+ * NOTE: This interface is called from three places:
+ * 1) From acpi_ex_release_mutex, via an AML Acquire() operator
+ * 2) From acpi_ex_release_global_lock when an AML Field access requires the
+ *    global lock
+ * 3) From the external interface, acpi_release_global_lock
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ex_release_mutex_object(union acpi_operand_object *obj_desc)
+{
+	acpi_status status = AE_OK;
+
+	ACPI_FUNCTION_TRACE(ex_release_mutex_object);
+
+	if (obj_desc->mutex.acquisition_depth == 0) {
+		return_ACPI_STATUS(AE_NOT_ACQUIRED);
+	}
+
+	/* Match multiple Acquires with multiple Releases */
+
+	obj_desc->mutex.acquisition_depth--;
+	if (obj_desc->mutex.acquisition_depth != 0) {
+
+		/* Just decrement the depth and return */
+
+		return_ACPI_STATUS(AE_OK);
+	}
+
+	if (obj_desc->mutex.owner_thread) {
+
+		/* Unlink the mutex from the owner's list */
+
+		acpi_ex_unlink_mutex(obj_desc);
+		obj_desc->mutex.owner_thread = NULL;
+	}
+
+	/* Release the mutex, special case for Global Lock */
+
+	if (obj_desc == acpi_gbl_global_lock_mutex) {
+		status = acpi_ev_release_global_lock();
+	} else {
+		acpi_os_release_mutex(obj_desc->mutex.os_mutex);
+	}
+
+	/* Clear mutex info */
+
+	obj_desc->mutex.thread_id = 0;
+	return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_release_mutex
+ *
+ * PARAMETERS:  obj_desc            - The object descriptor for this op
+ *              walk_state          - Current method execution state
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Release a previously acquired Mutex.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_release_mutex(union acpi_operand_object *obj_desc,
+		      struct acpi_walk_state *walk_state)
+{
+	acpi_status status = AE_OK;
+	u8 previous_sync_level;
+	struct acpi_thread_state *owner_thread;
+
+	ACPI_FUNCTION_TRACE(ex_release_mutex);
+
+	if (!obj_desc) {
+		return_ACPI_STATUS(AE_BAD_PARAMETER);
+	}
+
+	owner_thread = obj_desc->mutex.owner_thread;
+
+	/* The mutex must have been previously acquired in order to release it */
+
+	if (!owner_thread) {
+		ACPI_ERROR((AE_INFO,
+			    "Cannot release Mutex [%4.4s], not acquired",
+			    acpi_ut_get_node_name(obj_desc->mutex.node)));
+		return_ACPI_STATUS(AE_AML_MUTEX_NOT_ACQUIRED);
+	}
+
+	/* Must have a valid thread ID */
+
+	if (!walk_state->thread) {
+		ACPI_ERROR((AE_INFO,
+			    "Cannot release Mutex [%4.4s], null thread info",
+			    acpi_ut_get_node_name(obj_desc->mutex.node)));
+		return_ACPI_STATUS(AE_AML_INTERNAL);
+	}
+
+	/*
+	 * The Mutex is owned, but this thread must be the owner.
+	 * Special case for Global Lock, any thread can release
+	 */
+	if ((owner_thread->thread_id != walk_state->thread->thread_id) &&
+	    (obj_desc != acpi_gbl_global_lock_mutex)) {
+		ACPI_ERROR((AE_INFO,
+			    "Thread %u cannot release Mutex [%4.4s] acquired by thread %u",
+			    (u32)walk_state->thread->thread_id,
+			    acpi_ut_get_node_name(obj_desc->mutex.node),
+			    (u32)owner_thread->thread_id));
+		return_ACPI_STATUS(AE_AML_NOT_OWNER);
+	}
+
+	/*
+	 * The sync level of the mutex must be equal to the current sync level. In
+	 * other words, the current level means that at least one mutex at that
+	 * level is currently being held. Attempting to release a mutex of a
+	 * different level can only mean that the mutex ordering rule is being
+	 * violated. This behavior is clarified in ACPI 4.0 specification.
+	 */
+	if (obj_desc->mutex.sync_level != owner_thread->current_sync_level) {
+		ACPI_ERROR((AE_INFO,
+			    "Cannot release Mutex [%4.4s], SyncLevel mismatch: mutex %u current %u",
+			    acpi_ut_get_node_name(obj_desc->mutex.node),
+			    obj_desc->mutex.sync_level,
+			    walk_state->thread->current_sync_level));
+		return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
+	}
+
+	/*
+	 * Get the previous sync_level from the head of the acquired mutex list.
+	 * This handles the case where several mutexes at the same level have been
+	 * acquired, but are not released in reverse order.
+	 */
+	previous_sync_level =
+	    owner_thread->acquired_mutex_list->mutex.original_sync_level;
+
+	status = acpi_ex_release_mutex_object(obj_desc);
+	if (ACPI_FAILURE(status)) {
+		return_ACPI_STATUS(status);
+	}
+
+	if (obj_desc->mutex.acquisition_depth == 0) {
+
+		/* Restore the previous sync_level */
+
+		owner_thread->current_sync_level = previous_sync_level;
+	}
+
+	return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_release_all_mutexes
+ *
+ * PARAMETERS:  thread              - Current executing thread object
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Release all mutexes held by this thread
+ *
+ * NOTE: This function is called as the thread is exiting the interpreter.
+ * Mutexes are not released when an individual control method is exited, but
+ * only when the parent thread actually exits the interpreter. This allows one
+ * method to acquire a mutex, and a different method to release it, as long as
+ * this is performed underneath a single parent control method.
+ *
+ ******************************************************************************/
+
+void acpi_ex_release_all_mutexes(struct acpi_thread_state *thread)
+{
+	union acpi_operand_object *next = thread->acquired_mutex_list;
+	union acpi_operand_object *obj_desc;
+
+	ACPI_FUNCTION_NAME(ex_release_all_mutexes);
+
+	/* Traverse the list of owned mutexes, releasing each one */
+
+	while (next) {
+		obj_desc = next;
+		next = obj_desc->mutex.next;
+
+		obj_desc->mutex.prev = NULL;
+		obj_desc->mutex.next = NULL;
+		obj_desc->mutex.acquisition_depth = 0;
+
+		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
+				  "Force-releasing held mutex: %p\n",
+				  obj_desc));
+
+		/* Release the mutex, special case for Global Lock */
+
+		if (obj_desc == acpi_gbl_global_lock_mutex) {
+
+			/* Ignore errors */
+
+			(void)acpi_ev_release_global_lock();
+		} else {
+			acpi_os_release_mutex(obj_desc->mutex.os_mutex);
+		}
+
+		/* Mark mutex unowned */
+
+		obj_desc->mutex.owner_thread = NULL;
+		obj_desc->mutex.thread_id = 0;
+
+		/* Update Thread sync_level (Last mutex is the important one) */
+
+		thread->current_sync_level =
+		    obj_desc->mutex.original_sync_level;
+	}
+}