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iokit/Kernel/IOWorkLoop.cpp xnu-1228 xnu-344.49
--- xnu/xnu-1228/iokit/Kernel/IOWorkLoop.cpp
+++ xnu/xnu-344.49/iokit/Kernel/IOWorkLoop.cpp
@@ -1,19 +1,16 @@
 /*
- * Copyright (c) 1998-2007 Apple Inc. All rights reserved.
+ * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
- * 
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
@@ -23,7 +20,7 @@
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ * @APPLE_LICENSE_HEADER_END@
  */
 /*
 Copyright (c) 1998 Apple Computer, Inc.  All rights reserved.
@@ -37,7 +34,6 @@
 #include <IOKit/IOInterruptEventSource.h>
 #include <IOKit/IOCommandGate.h>
 #include <IOKit/IOTimeStamp.h>
-#include <libkern/OSDebug.h>
 
 #define super OSObject
 
@@ -45,8 +41,8 @@
 
 // Block of unused functions intended for future use
 OSMetaClassDefineReservedUsed(IOWorkLoop, 0);
-OSMetaClassDefineReservedUsed(IOWorkLoop, 1);
-
+
+OSMetaClassDefineReservedUnused(IOWorkLoop, 1);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 2);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 3);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 4);
@@ -55,69 +51,57 @@
 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
+
+extern "C" extern void stack_privilege( thread_t thread);
+
+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
     if ( !super::init() )
         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;
-    }
+
+    if ( !(gateLock = IORecursiveLockAlloc()) )
+        return false;
+
+    if ( !(workToDoLock = IOSimpleLockAlloc()) )
+        return false;
+
+    controlG = IOCommandGate::
+	commandGate(this, (IOCommandGate::Action) &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;
+
+    workThread = IOCreateThread(launchThreadMain, (void *) this);
+    if (!workThread)
+        return false;
 
     return true;
 }
@@ -125,25 +109,10 @@
 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();
+        me->free();
         return 0;
     }
 
@@ -160,7 +129,7 @@
 	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
+	// in this case disable all of the event source, mark the loop for
 	// 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.
@@ -186,9 +155,9 @@
         }
         eventChain = 0;
 
-	// 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.
+	// 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.
 	
 	if (controlG) {
 	    controlG->release();
@@ -203,10 +172,6 @@
 	if (gateLock) {
 	    IORecursiveLockFree(gateLock);
 	    gateLock = 0;
-	}
-	if (reserved) {
-	    IODelete(reserved, ExpansionData, 1);
-	    reserved = 0;
 	}
 
 	super::free();
@@ -290,58 +255,56 @@
 
 #endif /* KDEBUG */
 
-/* virtual */ bool IOWorkLoop::runEventSources()
-{
-    bool res = false;
-    closeGate();
-    if (ISSETP(&fFlags, kLoopTerminate))
-	goto abort;
+void IOWorkLoop::threadMainContinuation()
+{
+  IOWorkLoop* self;
+  self = (IOWorkLoop *) thread_get_cont_arg();
+
+  self->threadMain();
+}
+
+void IOWorkLoop::threadMain()
+{
+    CLRP(&fFlags, kLoopRestart);
+
+    for (;;) {
+        bool more;
+	IOInterruptState is;
 
     IOTimeWorkS();
-    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;
+
+        closeGate();
+        if (ISSETP(&fFlags, kLoopTerminate))
+	    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();
 
-abort:
-    openGate();
-    return res;
-}
-
-/* virtual */ void IOWorkLoop::threadMain()
-{
-restartThread:
-    do {
-	if ( !runEventSources() )
-	    goto exitThread;
-
-	IOInterruptState is = IOSimpleLockLockDisableInterrupt(workToDoLock);
+        openGate();
+
+	is = IOSimpleLockLockDisableInterrupt(workToDoLock);
         if ( !ISSETP(&fFlags, kLoopTerminate) && !workToDo) {
 	    assert_wait((void *) &workToDo, false);
 	    IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
-	    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;
+
+	    thread_set_cont_arg((int) this);
+	    thread_block(&threadMainContinuation);
 	    /* NOTREACHED */
 	}
 
@@ -349,7 +312,11 @@
 	// to commit suicide.  But no matter 
 	// Clear the simple lock and retore the interrupt state
 	IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
-    } while(workToDo);
+	if (workToDo)
+	    continue;
+	else
+	    break;
+    }
 
 exitThread:
     workThread = 0;	// Say we don't have a loop and free ourselves
@@ -409,8 +376,8 @@
 }
 
 IOReturn IOWorkLoop::runAction(Action inAction, OSObject *target,
-                                  void *arg0, void *arg1,
-                                  void *arg2, void *arg3)
+                                  void *arg0 = 0, void *arg1 = 0,
+                                  void *arg2 = 0, void *arg3 = 0)
 {
     IOReturn res;