--- xnu/xnu-792.22.5/iokit/Kernel/IOWorkLoop.cpp
+++ xnu/xnu-1228/iokit/Kernel/IOWorkLoop.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1998-2007 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
@@ -37,6 +37,7 @@
 #include <IOKit/IOInterruptEventSource.h>
 #include <IOKit/IOCommandGate.h>
 #include <IOKit/IOTimeStamp.h>
+#include <libkern/OSDebug.h>
 
 #define super OSObject
 
@@ -54,12 +55,21 @@
 OSMetaClassDefineReservedUnused(IOWorkLoop, 7);
 
 enum IOWorkLoopState { kLoopRestart = 0x1, kLoopTerminate = 0x2 };
+#ifdef __ppc__
 static inline void SETP(void *addr, unsigned int flag)
     { unsigned int *num = (unsigned int *) addr; *num |= flag; }
 static inline void CLRP(void *addr, unsigned int flag)
     { unsigned int *num = (unsigned int *) addr; *num &= ~flag; }
 static inline bool ISSETP(void *addr, unsigned int flag)
     { unsigned int *num = (unsigned int *) addr; return (*num & flag) != 0; }
+#else
+static inline void SETP(void *addr, unsigned int flag)
+    { unsigned char *num = (unsigned char *) addr; *num |= flag; }
+static inline void CLRP(void *addr, unsigned int flag)
+    { unsigned char *num = (unsigned char *) addr; *num &= ~flag; }
+static inline bool ISSETP(void *addr, unsigned int flag)
+    { unsigned char *num = (unsigned char *) addr; return (*num & flag) != 0; }
+#endif
 
 #define fFlags loopRestart
 
@@ -68,34 +78,46 @@
     // The super init and gateLock allocation MUST be done first
     if ( !super::init() )
         return false;
-
-    if ( !(gateLock = IORecursiveLockAlloc()) )
-        return false;
-
-    if ( !(workToDoLock = IOSimpleLockAlloc()) )
-        return false;
-
-    controlG = IOCommandGate::
-	commandGate(this, OSMemberFunctionCast(IOCommandGate::Action,
-					this, &IOWorkLoop::_maintRequest));
-    if ( !controlG )
-        return false;
-
-    IOSimpleLockInit(workToDoLock);
-    workToDo = false;
-
-    // Point the controlGate at the workLoop.  Usually addEventSource
-    // does this automatically.  The problem is in this case addEventSource
-    // uses the control gate and it has to be bootstrapped.
-    controlG->setWorkLoop(this);
-    if (addEventSource(controlG) != kIOReturnSuccess)
-        return false;
-
-    IOThreadFunc cptr =
-	OSMemberFunctionCast(IOThreadFunc, this, &IOWorkLoop::threadMain);
-    workThread = IOCreateThread(cptr, this);
-    if (!workThread)
-        return false;
+	
+    if ( gateLock == NULL ) {
+        if ( !( gateLock = IORecursiveLockAlloc()) )
+            return false;
+    }
+	
+    if ( workToDoLock == NULL ) {
+        if ( !(workToDoLock = IOSimpleLockAlloc()) )
+            return false;
+        IOSimpleLockInit(workToDoLock);
+        workToDo = false;
+    }
+
+    if ( controlG == NULL ) {
+        controlG = IOCommandGate::commandGate(
+            this,
+            OSMemberFunctionCast(
+                IOCommandGate::Action,
+                this,
+                &IOWorkLoop::_maintRequest));
+
+        if ( !controlG )
+            return false;
+        // Point the controlGate at the workLoop.  Usually addEventSource
+        // does this automatically.  The problem is in this case addEventSource
+        // uses the control gate and it has to be bootstrapped.
+        controlG->setWorkLoop(this);
+        if (addEventSource(controlG) != kIOReturnSuccess)
+            return false;
+    }
+
+    if ( workThread == NULL ) {
+        IOThreadFunc cptr = OSMemberFunctionCast(
+            IOThreadFunc,
+            this,
+            &IOWorkLoop::threadMain);
+        workThread = IOCreateThread(cptr, this);
+        if (!workThread)
+            return false;
+    }
 
     return true;
 }
@@ -103,7 +125,22 @@
 IOWorkLoop *
 IOWorkLoop::workLoop()
 {
+    return IOWorkLoop::workLoopWithOptions(0);
+}
+
+IOWorkLoop *
+IOWorkLoop::workLoopWithOptions(IOOptionBits options)
+{
     IOWorkLoop *me = new IOWorkLoop;
+
+    if (me && options) {
+	me->reserved = IONew(ExpansionData, 1);
+	if (!me->reserved) {
+	    me->release();
+	    return 0;
+	}
+	me->reserved->options = options;
+    }
 
     if (me && !me->init()) {
         me->release();
@@ -123,7 +160,7 @@
 	IOInterruptState is;
 
 	// If we are here then we must be trying to shut down this work loop
-	// in this case disable all of the event source, mark the loop for
+	// in this case disable all of the event source, mark the loop
 	// as terminating and wakeup the work thread itself and return
 	// Note: we hold the gate across the entire operation mainly for the 
 	// benefit of our event sources so we can disable them cleanly.
@@ -149,9 +186,9 @@
         }
         eventChain = 0;
 
-	// Either we have a partial initialisation to clean up
-	// or we the workThread itself is performing hari-kari.
-	// either way clean up all of our resources and return.
+	// Either we have a partial initialization to clean up
+	// or the workThread itself is performing hari-kari.
+	// Either way clean up all of our resources and return.
 	
 	if (controlG) {
 	    controlG->release();
@@ -166,6 +203,10 @@
 	if (gateLock) {
 	    IORecursiveLockFree(gateLock);
 	    gateLock = 0;
+	}
+	if (reserved) {
+	    IODelete(reserved, ExpansionData, 1);
+	    reserved = 0;
 	}
 
 	super::free();
@@ -286,6 +327,7 @@
 
 /* virtual */ void IOWorkLoop::threadMain()
 {
+restartThread:
     do {
 	if ( !runEventSources() )
 	    goto exitThread;
@@ -294,10 +336,12 @@
         if ( !ISSETP(&fFlags, kLoopTerminate) && !workToDo) {
 	    assert_wait((void *) &workToDo, false);
 	    IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
-
-	    thread_continue_t cptr = OSMemberFunctionCast(
-		    thread_continue_t, this, &IOWorkLoop::threadMain);
+	    thread_continue_t cptr = NULL;
+	    if (!reserved || !(kPreciousStack & reserved->options))
+		cptr = OSMemberFunctionCast(
+			thread_continue_t, this, &IOWorkLoop::threadMain);
 	    thread_block_parameter(cptr, this);
+	    goto restartThread;
 	    /* NOTREACHED */
 	}