/*
- * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1998-2009 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
actually a lie but the work-loop single threaded semantic is maintained for this
event source. Using the work-loop gate rather than execution by the workloop.
The command gate tests for a potential self dead lock by checking if the
-runCommand request is made from the work-loop's thread, it doens't check for a
+runCommand request is made from the work-loop's thread, it doesn't check for a
mutual dead lock though where a pair of work loop's dead lock each other.
<br><br>
The IOCommandGate is a lighter weight version of the IOCommandQueue and
queue internal to the device or the device's family. Otherwise if the hardware
is inactive then this request can be acted upon immediately.
<br><br>
- CAUTION: The runAction and runCommand functions can not be called from an interrupt context. But attemptCommand can, though it may return an error
+ CAUTION: The runAction, runCommand, and attemptCommand functions cannot be called from an interrupt context.
*/
class IOCommandGate : public IOEventSource
void *arg2, void *arg3);
protected:
-/*!
- @function checkForWork
- @abstract Not used, $link IOEventSource::checkForWork(). */
- virtual bool checkForWork();
/*! @struct ExpansionData
@discussion This structure will be used to expand the capablilties of the IOWorkLoop in the future.
@result True if inherited classes initialise successfully. */
virtual bool init(OSObject *owner, Action action = 0);
-#if !(defined(__ppc__) && defined(KPI_10_4_0_PPC_COMPAT))
// Superclass overrides
virtual void free();
virtual void setWorkLoop(IOWorkLoop *inWorkLoop);
-#endif
/*! @function runCommand
@abstract Single thread a command with the target work-loop.
/*! @function commandSleep
@abstract Put a thread that is currently holding the command gate to sleep.
- @discussion Put a thread to sleep waiting for an event but release the gate first. If the event occurs then the commandGate is closed before the returns.
+ @discussion Put a thread to sleep waiting for an event but release the gate first. If the event occurs then the commandGate is closed before the function returns.
@param event Pointer to an address.
- @param interruptible THREAD_UNINT, THREAD_INTERRUPTIBLE or THREAD_ABORTSAFE, defaults to THREAD_ABORTSAFE.
- @result THREAD_AWAKENED - normal wakeup, THREAD_TIMED_OUT - timeout expired, THREAD_INTERRUPTED - interrupted by clear_wait, THREAD_RESTART - restart operation entirely, kIOReturnNotPermitted if the calling thread does not hold the command gate. */
+ @param interruptible THREAD_UNINT, THREAD_INTERRUPTIBLE or THREAD_ABORTSAFE. THREAD_UNINT specifies that the sleep cannot be interrupted by a signal. THREAD_INTERRUPTIBLE specifies that the sleep may be interrupted by a "kill -9" signal. THREAD_ABORTSAFE (the default value) specifies that the sleep may be interrupted by any user signal.
+ @result THREAD_AWAKENED - normal wakeup, THREAD_TIMED_OUT - timeout expired, THREAD_INTERRUPTED - interrupted, THREAD_RESTART - restart operation entirely, kIOReturnNotPermitted if the calling thread does not hold the command gate. */
virtual IOReturn commandSleep(void *event,
UInt32 interruptible = THREAD_ABORTSAFE);
@param onlyOneThread true to only wake up at most one thread, false otherwise. */
virtual void commandWakeup(void *event, bool oneThread = false);
-#if !(defined(__ppc__) && defined(KPI_10_4_0_PPC_COMPAT))
/*! @function disable
@abstract Disable the command gate
@discussion When a command gate is disabled all future calls to runAction and runCommand will stall until the gate is enable()d later. This can be used to block client threads when a system sleep is requested. The IOWorkLoop thread itself will never stall, even when making runAction/runCommand calls. This call must be made from a gated context, to clear potential race conditions. */
@abstract Enable command gate, this will unblock any blocked Commands and Actions.
@discussion Enable the command gate. The attemptAction/attemptCommand calls will now be enabled and can succeeed. Stalled runCommand/runAction calls will be woken up. */
virtual void enable();
-#endif
+
+/*! @function commandSleep
+ @abstract Put a thread that is currently holding the command gate to sleep.
+ @discussion Put a thread to sleep waiting for an event but release the gate first. If the event occurs or timeout occurs then the commandGate is closed before the function returns.
+ @param event Pointer to an address.
+ @param deadline Clock deadline to timeout the sleep.
+ @param interruptible THREAD_UNINT, THREAD_INTERRUPTIBLE or THREAD_ABORTSAFE. THREAD_UNINT specifies that the sleep cannot be interrupted by a signal. THREAD_INTERRUPTIBLE specifies that the sleep may be interrupted by a "kill -9" signal. THREAD_ABORTSAFE specifies that the sleep may be interrupted by any user signal.
+ @result THREAD_AWAKENED - normal wakeup, THREAD_TIMED_OUT - timeout expired, THREAD_INTERRUPTED - interrupted, THREAD_RESTART - restart operation entirely, kIOReturnNotPermitted if the calling thread does not hold the command gate. */
+ virtual IOReturn commandSleep(void *event,
+ AbsoluteTime deadline,
+ UInt32 interruptible);
private:
+#if __LP64__
OSMetaClassDeclareReservedUnused(IOCommandGate, 0);
+#else
+ OSMetaClassDeclareReservedUsed(IOCommandGate, 0);
+#endif
OSMetaClassDeclareReservedUnused(IOCommandGate, 1);
OSMetaClassDeclareReservedUnused(IOCommandGate, 2);
OSMetaClassDeclareReservedUnused(IOCommandGate, 3);
projects / apple / xnu.git / blobdiff