xnu-1504.7.4.tar.gz

[apple/xnu.git] / iokit / Kernel / IOLocks.cpp

diff --git a/iokit/Kernel/IOLocks.cpp b/iokit/Kernel/IOLocks.cpp
index edd23bea95f7d9db26f727e2147839a1e89418c5..a61f6a326ac7d3bd1509fcb4d02d1060fff514f7 100644 (file)
--- a/iokit/Kernel/IOLocks.cpp
+++ b/iokit/Kernel/IOLocks.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@
  * 
@@ -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>
 
@@ -41,6 +32,8 @@
 #include <IOKit/IOLib.h> 
 #include <IOKit/assert.h>
 
+#include <IOKit/IOLocksPrivate.h>
+
 extern "C" {
 #include <kern/locks.h>
 
@@ -84,42 +77,53 @@ void        IOLockWakeup(IOLock * lock, void *event, bool oneThread)
 
 
 struct _IORecursiveLock {
-    lck_mtx_t   *mutex;
-    thread_t   thread;
-    UInt32     count;
+       lck_mtx_t       *mutex;
+       lck_grp_t       *group;
+       thread_t        thread;
+       UInt32          count;
 };
 
-IORecursiveLock * IORecursiveLockAlloc( void )
+IORecursiveLock * IORecursiveLockAllocWithLockGroup( lck_grp_t * lockGroup )
 {
     _IORecursiveLock * lock;
 
-    lock = IONew( _IORecursiveLock, 1);
-    if( !lock)
+    if( lockGroup == 0 )
+        return( 0 );
+
+    lock = IONew( _IORecursiveLock, 1 );
+    if( !lock )
         return( 0 );
 
-    lock->mutex = lck_mtx_alloc_init(IOLockGroup, LCK_ATTR_NULL);
-    if( lock->mutex) {
+    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);
+        IODelete( lock, _IORecursiveLock, 1 );
         lock = 0;
     }
 
     return( (IORecursiveLock *) lock );
 }
 
+
+IORecursiveLock * IORecursiveLockAlloc( void )
+{
+    return IORecursiveLockAllocWithLockGroup( IOLockGroup );
+}
+
 void IORecursiveLockFree( IORecursiveLock * _lock )
 {
     _IORecursiveLock * lock = (_IORecursiveLock *)_lock;
-
-    lck_mtx_free( lock->mutex , IOLockGroup);
-    IODelete( lock, _IORecursiveLock, 1);
+       
+    lck_mtx_free( lock->mutex, lock->group );
+    IODelete( lock, _IORecursiveLock, 1 );
 }
 
-lck_mtx_t * IORecursiveLockGetMachLock( IORecursiveLock * lock)
+lck_mtx_t * IORecursiveLockGetMachLock( IORecursiveLock * lock )
 {
-    return( lock->mutex);
+    return( lock->mutex );
 }
 
 void IORecursiveLockLock( IORecursiveLock * _lock)
@@ -182,7 +186,6 @@ int IORecursiveLockSleep(IORecursiveLock *_lock, void *event, UInt32 interType)
     int res;
 
     assert(lock->thread == IOThreadSelf());
-    assert(lock->count == 1 || interType == THREAD_UNINT);
     
     lock->count = 0;
     lock->thread = 0;
@@ -197,6 +200,29 @@ int IORecursiveLockSleep(IORecursiveLock *_lock, void *event, UInt32 interType)
     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_DEFAULT, (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);