--- xnu/xnu-1228.3.13/iokit/Kernel/IOLocks.cpp
+++ xnu/xnu-3789.51.2/iokit/Kernel/IOLocks.cpp
@@ -25,15 +25,6 @@
  * 
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
-/*
- * Copyright (c) 1998 Apple Computer, Inc.  All rights reserved. 
- *
- * HISTORY
- *
- */
-
-
-#define	IOLOCKS_CPP	1
 
 #include <IOKit/system.h>
 
@@ -46,6 +37,11 @@
 extern "C" {
 #include <kern/locks.h>
 
+#if defined(__x86_64__)
+/* Synthetic event if none is specified, for backwards compatibility only. */
+static bool IOLockSleep_NO_EVENT __attribute__((used)) = 0;
+#endif
+
 void	IOLockInitWithState( IOLock * lock, IOLockState state)
 {
     if( state == kIOLockStateLocked)
@@ -69,13 +65,13 @@
 
 int	IOLockSleep( IOLock * lock, void *event, UInt32 interType)
 {
-    return (int) lck_mtx_sleep(lock, LCK_SLEEP_DEFAULT, (event_t) event, (wait_interrupt_t) interType);
+    return (int) lck_mtx_sleep(lock, LCK_SLEEP_PROMOTED_PRI, (event_t) event, (wait_interrupt_t) interType);
 }
 
 int	IOLockSleepDeadline( IOLock * lock, void *event,
                                 AbsoluteTime deadline, UInt32 interType)
 {
-    return (int) lck_mtx_sleep_deadline(lock, LCK_SLEEP_DEFAULT, (event_t) event,
+    return (int) lck_mtx_sleep_deadline(lock, LCK_SLEEP_PROMOTED_PRI, (event_t) event,
     					(wait_interrupt_t) interType, __OSAbsoluteTime(deadline));
 }
 
@@ -84,9 +80,45 @@
 	thread_wakeup_prim((event_t) event, oneThread, THREAD_AWAKENED);
 }   
 
+#if defined(__x86_64__)
+/*
+ * For backwards compatibility, kexts built against pre-Darwin 14 headers will bind at runtime to this function,
+ * which supports a NULL event,
+ */
+int	IOLockSleep_legacy_x86_64( IOLock * lock, void *event, UInt32 interType) __asm("_IOLockSleep");
+int	IOLockSleepDeadline_legacy_x86_64( IOLock * lock, void *event,
+					   AbsoluteTime deadline, UInt32 interType) __asm("_IOLockSleepDeadline");
+void	IOLockWakeup_legacy_x86_64(IOLock * lock, void *event, bool oneThread) __asm("_IOLockWakeup");
+
+int	IOLockSleep_legacy_x86_64( IOLock * lock, void *event, UInt32 interType)
+{
+    if (event == NULL)
+        event = (void *)&IOLockSleep_NO_EVENT;
+
+    return IOLockSleep(lock, event, interType);
+}
+
+int	IOLockSleepDeadline_legacy_x86_64( IOLock * lock, void *event,
+			     AbsoluteTime deadline, UInt32 interType)
+{
+    if (event == NULL)
+        event = (void *)&IOLockSleep_NO_EVENT;
+
+    return IOLockSleepDeadline(lock, event, deadline, interType);
+}
+
+void	IOLockWakeup_legacy_x86_64(IOLock * lock, void *event, bool oneThread)
+{   
+    if (event == NULL)
+        event = (void *)&IOLockSleep_NO_EVENT;
+
+    IOLockWakeup(lock, event, oneThread);
+}   
+#endif /* defined(__x86_64__) */
+
 
 struct _IORecursiveLock {
-	lck_mtx_t	*mutex;
+	lck_mtx_t	mutex;
 	lck_grp_t	*group;
 	thread_t	thread;
 	UInt32		count;
@@ -103,15 +135,10 @@
     if( !lock )
         return( 0 );
 
-    lock->mutex = lck_mtx_alloc_init( lockGroup, LCK_ATTR_NULL );
-    if( lock->mutex ) {
-		lock->group = lockGroup;
-        lock->thread = 0;
-        lock->count  = 0;
-    } else {
-        IODelete( lock, _IORecursiveLock, 1 );
-        lock = 0;
-    }
+    lck_mtx_init( &lock->mutex, lockGroup, LCK_ATTR_NULL );
+    lock->group = lockGroup;
+    lock->thread = 0;
+    lock->count  = 0;
 
     return( (IORecursiveLock *) lock );
 }
@@ -126,13 +153,13 @@
 {
     _IORecursiveLock * lock = (_IORecursiveLock *)_lock;
 	
-    lck_mtx_free( lock->mutex, lock->group );
+    lck_mtx_destroy(&lock->mutex, lock->group);
     IODelete( lock, _IORecursiveLock, 1 );
 }
 
 lck_mtx_t * IORecursiveLockGetMachLock( IORecursiveLock * lock )
 {
-    return( lock->mutex );
+    return( &lock->mutex );
 }
 
 void IORecursiveLockLock( IORecursiveLock * _lock)
@@ -142,7 +169,7 @@
     if( lock->thread == IOThreadSelf())
         lock->count++;
     else {
-        lck_mtx_lock( lock->mutex );
+        lck_mtx_lock( &lock->mutex );
         assert( lock->thread == 0 );
         assert( lock->count == 0 );
         lock->thread = IOThreadSelf();
@@ -158,7 +185,7 @@
         lock->count++;
 	return( true );
     } else {
-        if( lck_mtx_try_lock( lock->mutex )) {
+        if( lck_mtx_try_lock( &lock->mutex )) {
             assert( lock->thread == 0 );
             assert( lock->count == 0 );
             lock->thread = IOThreadSelf();
@@ -177,7 +204,7 @@
 
     if( 0 == (--lock->count)) {
         lock->thread = 0;
-        lck_mtx_unlock( lock->mutex );
+        lck_mtx_unlock( &lock->mutex );
     }
 }
 
@@ -195,11 +222,10 @@
     int res;
 
     assert(lock->thread == IOThreadSelf());
-    assert(lock->count == 1 || interType == THREAD_UNINT);
     
     lock->count = 0;
     lock->thread = 0;
-    res = lck_mtx_sleep(lock->mutex, LCK_SLEEP_DEFAULT, (event_t) event, (wait_interrupt_t) interType);
+    res = lck_mtx_sleep(&lock->mutex, LCK_SLEEP_PROMOTED_PRI, (event_t) event, (wait_interrupt_t) interType);
 
     // Must re-establish the recursive lock no matter why we woke up
     // otherwise we would potentially leave the return path corrupted.
@@ -210,6 +236,29 @@
     return res;
 }
 
+int	IORecursiveLockSleepDeadline( IORecursiveLock * _lock, void *event,
+                                  AbsoluteTime deadline, UInt32 interType)
+{
+    _IORecursiveLock * lock = (_IORecursiveLock *)_lock;
+    UInt32 count = lock->count;
+    int res;
+
+    assert(lock->thread == IOThreadSelf());
+    
+    lock->count = 0;
+    lock->thread = 0;
+    res = lck_mtx_sleep_deadline(&lock->mutex, LCK_SLEEP_PROMOTED_PRI, (event_t) event,
+								      (wait_interrupt_t) interType, __OSAbsoluteTime(deadline));
+
+    // Must re-establish the recursive lock no matter why we woke up
+    // otherwise we would potentially leave the return path corrupted.
+    assert(lock->thread == 0);
+    assert(lock->count == 0);
+    lock->thread = IOThreadSelf();
+    lock->count = count;
+    return res;
+}
+
 void IORecursiveLockWakeup(IORecursiveLock *, void *event, bool oneThread)
 {
     thread_wakeup_prim((event_t) event, oneThread, THREAD_AWAKENED);