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iokit/Kernel/IOWorkLoop.cpp xnu-124.13 xnu-792.25.20
--- xnu/xnu-124.13/iokit/Kernel/IOWorkLoop.cpp
+++ xnu/xnu-792.25.20/iokit/Kernel/IOWorkLoop.cpp
@@ -37,8 +37,9 @@
 OSDefineMetaClassAndStructors(IOWorkLoop, OSObject);
 
 // Block of unused functions intended for future use
-OSMetaClassDefineReservedUnused(IOWorkLoop, 0);
-OSMetaClassDefineReservedUnused(IOWorkLoop, 1);
+OSMetaClassDefineReservedUsed(IOWorkLoop, 0);
+OSMetaClassDefineReservedUsed(IOWorkLoop, 1);
+
 OSMetaClassDefineReservedUnused(IOWorkLoop, 2);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 3);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 4);
@@ -56,16 +57,6 @@
 
 #define fFlags loopRestart
 
-void IOWorkLoop::launchThreadMain(void *self)
-{
-    register thread_t mythread = current_thread();
-
-    // Make sure that this thread always has a kernel stack
-    stack_privilege(mythread);
-    thread_set_cont_arg((int) self);
-    threadMainContinuation();
-}
-
 bool IOWorkLoop::init()
 {
     // The super init and gateLock allocation MUST be done first
@@ -79,7 +70,8 @@
         return false;
 
     controlG = IOCommandGate::
-	commandGate(this, (IOCommandGate::Action) &IOWorkLoop::_maintRequest);
+	commandGate(this, OSMemberFunctionCast(IOCommandGate::Action,
+					this, &IOWorkLoop::_maintRequest));
     if ( !controlG )
         return false;
 
@@ -93,7 +85,9 @@
     if (addEventSource(controlG) != kIOReturnSuccess)
         return false;
 
-    workThread = IOCreateThread(launchThreadMain, (void *) this);
+    IOThreadFunc cptr =
+	OSMemberFunctionCast(IOThreadFunc, this, &IOWorkLoop::threadMain);
+    workThread = IOCreateThread(cptr, this);
     if (!workThread)
         return false;
 
@@ -106,7 +100,7 @@
     IOWorkLoop *me = new IOWorkLoop;
 
     if (me && !me->init()) {
-        me->free();
+        me->release();
         return 0;
     }
 
@@ -249,61 +243,55 @@
 
 #endif /* KDEBUG */
 
-void IOWorkLoop::threadMainContinuation()
-{
-  IOWorkLoop* self;
-  self = (IOWorkLoop *) thread_get_cont_arg();
-
-  self->threadMain();
-}
-
-void IOWorkLoop::threadMain()
-{
-    CLRP(&fFlags, kLoopRestart);
-
-    for (;;) {
-        bool more;
-	IOInterruptState is;
+/* virtual */ bool IOWorkLoop::runEventSources()
+{
+    bool res = false;
+    closeGate();
+    if (ISSETP(&fFlags, kLoopTerminate))
+	goto abort;
 
     IOTimeWorkS();
-
-        closeGate();
-        if (ISSETP(&fFlags, kLoopTerminate))
+    bool more;
+    do {
+	CLRP(&fFlags, kLoopRestart);
+	workToDo = more = false;
+	for (IOEventSource *evnt = eventChain; evnt; evnt = evnt->getNext()) {
+
+	    IOTimeClientS();
+	    more |= evnt->checkForWork();
+	    IOTimeClientE();
+
+	    if (ISSETP(&fFlags, kLoopTerminate))
+		goto abort;
+	    else if (fFlags & kLoopRestart) {
+		more = true;
+		break;
+	    }
+	}
+    } while (more);
+
+    res = true;
+    IOTimeWorkE();
+
+abort:
+    openGate();
+    return res;
+}
+
+/* virtual */ void IOWorkLoop::threadMain()
+{
+    do {
+	if ( !runEventSources() )
 	    goto exitThread;
 
-        do {
-            workToDo = more = false;
-            for (IOEventSource *event = eventChain; event; event = event->getNext()) {
-
-            IOTimeClientS();
-                more |= event->checkForWork();
-            IOTimeClientE();
-
-		if (ISSETP(&fFlags, kLoopTerminate))
-		    goto exitThread;
-                else if (fFlags & kLoopRestart) {
-		    CLRP(&fFlags, kLoopRestart);
-                    continue;
-                }
-            }
-        } while (more);
-
-    IOTimeWorkE();
-
-        openGate();
-
-	is = IOSimpleLockLockDisableInterrupt(workToDoLock);
+	IOInterruptState is = IOSimpleLockLockDisableInterrupt(workToDoLock);
         if ( !ISSETP(&fFlags, kLoopTerminate) && !workToDo) {
 	    assert_wait((void *) &workToDo, false);
 	    IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
 
-#if defined (__i386__)
-	    thread_block(0);
-	    continue;
-#else
-	    thread_set_cont_arg((int) this);
-	    thread_block(&threadMainContinuation);
-#endif
+	    thread_continue_t cptr = OSMemberFunctionCast(
+		    thread_continue_t, this, &IOWorkLoop::threadMain);
+	    thread_block_parameter(cptr, this);
 	    /* NOTREACHED */
 	}
 
@@ -311,16 +299,12 @@
 	// to commit suicide.  But no matter 
 	// Clear the simple lock and retore the interrupt state
 	IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
-	if (workToDo)
-	    continue;
-	else
-	    break;
-    }
+    } while(workToDo);
 
 exitThread:
     workThread = 0;	// Say we don't have a loop and free ourselves
     free();
-    IOExitThread(0);
+    IOExitThread();
 }
 
 IOThread IOWorkLoop::getThread() const
@@ -374,6 +358,20 @@
     IORecursiveLockWakeup(gateLock, event, oneThread);
 }
 
+IOReturn IOWorkLoop::runAction(Action inAction, OSObject *target,
+                                  void *arg0, void *arg1,
+                                  void *arg2, void *arg3)
+{
+    IOReturn res;
+
+    // closeGate is recursive so don't worry if we already hold the lock.
+    closeGate();
+    res = (*inAction)(target, arg0, arg1, arg2, arg3);
+    openGate();
+
+    return res;
+}
+
 IOReturn IOWorkLoop::_maintRequest(void *inC, void *inD, void *, void *)
 {
     maintCommandEnum command = (maintCommandEnum) (vm_address_t) inC;
@@ -383,43 +381,48 @@
     switch (command)
     {
     case mAddEvent:
-	SETP(&fFlags, kLoopRestart);
-        inEvent->retain();
-        inEvent->setWorkLoop(this);
-        inEvent->setNext(0);
-
-        if (!eventChain)
-            eventChain = inEvent;
-        else {
-            IOEventSource *event, *next;
-
-            for (event = eventChain; (next = event->getNext()); event = next)
-                ;
-            event->setNext(inEvent);
+        if (!inEvent->getWorkLoop()) {
+            SETP(&fFlags, kLoopRestart);
+
+            inEvent->retain();
+            inEvent->setWorkLoop(this);
+            inEvent->setNext(0);
+    
+            if (!eventChain)
+                eventChain = inEvent;
+            else {
+                IOEventSource *event, *next;
+    
+                for (event = eventChain; (next = event->getNext()); event = next)
+                    ;
+                event->setNext(inEvent);
+            }
         }
         break;
 
     case mRemoveEvent:
-        if (eventChain == inEvent)
-            eventChain = inEvent->getNext();
-        else {
-            IOEventSource *event, *next;
-
-            event = eventChain;
-            while ((next = event->getNext()) && next != inEvent)
-                event = next;
-
-            if (!next) {
-                res = kIOReturnBadArgument;
-                break;
+        if (inEvent->getWorkLoop()) {
+            if (eventChain == inEvent)
+                eventChain = inEvent->getNext();
+            else {
+                IOEventSource *event, *next;
+    
+                event = eventChain;
+                while ((next = event->getNext()) && next != inEvent)
+                    event = next;
+    
+                if (!next) {
+                    res = kIOReturnBadArgument;
+                    break;
+                }
+                event->setNext(inEvent->getNext());
             }
-            event->setNext(inEvent->getNext());
+    
+            inEvent->setWorkLoop(0);
+            inEvent->setNext(0);
+            inEvent->release();
+            SETP(&fFlags, kLoopRestart);
         }
-
-        inEvent->setWorkLoop(0);
-        inEvent->setNext(0);
-        inEvent->release();
-	SETP(&fFlags, kLoopRestart);
         break;
 
     default: