xnu-3789.51.2.tar.gz

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

diff --git a/iokit/Kernel/IOCommandGate.cpp b/iokit/Kernel/IOCommandGate.cpp
index 73a7cc98e5f2aa651e2f05a7e234228291a15316..2308daf1b5bf0a67a0699f9c35c0d0dd00fe2b2f 100644 (file)
--- a/iokit/Kernel/IOCommandGate.cpp
+++ b/iokit/Kernel/IOCommandGate.cpp
@@ -1,16 +1,19 @@
 /*
 /*

- * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1998-2000, 2009-2010 Apple Inc. All rights reserved.

  *
  *

- * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

  * 
  * 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
  * 
  * 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. 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. 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.

  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER


@@ -20,17 +23,24 @@
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 

- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@

  */
  */

+#include <libkern/OSDebug.h>
+

 #include <IOKit/IOCommandGate.h>
 #include <IOKit/IOWorkLoop.h>
 #include <IOKit/IOReturn.h>
 #include <IOKit/IOTimeStamp.h>
 #include <IOKit/IOCommandGate.h>
 #include <IOKit/IOWorkLoop.h>
 #include <IOKit/IOReturn.h>
 #include <IOKit/IOTimeStamp.h>

+#include <IOKit/IOKitDebug.h>

 
 #define super IOEventSource
 
 OSDefineMetaClassAndStructors(IOCommandGate, IOEventSource)
 
 #define super IOEventSource
 
 OSDefineMetaClassAndStructors(IOCommandGate, IOEventSource)

+#if __LP64__

 OSMetaClassDefineReservedUnused(IOCommandGate, 0);
 OSMetaClassDefineReservedUnused(IOCommandGate, 0);

+#else
+OSMetaClassDefineReservedUsed(IOCommandGate, 0);
+#endif

 OSMetaClassDefineReservedUnused(IOCommandGate, 1);
 OSMetaClassDefineReservedUnused(IOCommandGate, 2);
 OSMetaClassDefineReservedUnused(IOCommandGate, 3);
 OSMetaClassDefineReservedUnused(IOCommandGate, 1);
 OSMetaClassDefineReservedUnused(IOCommandGate, 2);
 OSMetaClassDefineReservedUnused(IOCommandGate, 3);


@@ -39,131 +49,246 @@ OSMetaClassDefineReservedUnused(IOCommandGate, 5);
 OSMetaClassDefineReservedUnused(IOCommandGate, 6);
 OSMetaClassDefineReservedUnused(IOCommandGate, 7);
 
 OSMetaClassDefineReservedUnused(IOCommandGate, 6);
 OSMetaClassDefineReservedUnused(IOCommandGate, 7);
 

-bool IOCommandGate::checkForWork() { return false; }
+#if IOKITSTATS
+
+#define IOStatisticsInitializeCounter() \
+do { \
+       IOStatistics::setCounterType(IOEventSource::reserved->counter, kIOStatisticsCommandGateCounter); \
+} while (0)
+
+#define IOStatisticsActionCall() \
+do { \
+       IOStatistics::countCommandGateActionCall(IOEventSource::reserved->counter); \
+} while (0)
+
+#else
+
+#define IOStatisticsInitializeCounter()
+#define IOStatisticsActionCall()
+
+#endif /* IOKITSTATS */

 
 

-bool IOCommandGate::init(OSObject *inOwner, Action inAction = 0)
+bool IOCommandGate::init(OSObject *inOwner, Action inAction)

 {
 {

-    return super::init(inOwner, (IOEventSource::Action) inAction);
+    bool res = super::init(inOwner, (IOEventSource::Action) inAction);
+    if (res) {
+        IOStatisticsInitializeCounter();
+    }
+
+    return res;

 }
 
 IOCommandGate *
 }
 
 IOCommandGate *

-IOCommandGate::commandGate(OSObject *inOwner, Action inAction = 0)
+IOCommandGate::commandGate(OSObject *inOwner, Action inAction)

 {
     IOCommandGate *me = new IOCommandGate;
 
     if (me && !me->init(inOwner, inAction)) {
 {
     IOCommandGate *me = new IOCommandGate;
 
     if (me && !me->init(inOwner, inAction)) {

-        me->free();
+        me->release();

         return 0;
     }
 
     return me;
 }
 
         return 0;
     }
 
     return me;
 }
 

-IOReturn IOCommandGate::runCommand(void *arg0 = 0, void *arg1 = 0,
-                                   void *arg2 = 0, void *arg3 = 0)
+/* virtual */ void IOCommandGate::disable()

 {
 {

-    IOReturn res;
-
-    if (!enabled)
-        return kIOReturnNotPermitted;
-
-    if (!action)
-        return kIOReturnNoResources;
+    if (workLoop && !workLoop->inGate())
+       OSReportWithBacktrace("IOCommandGate::disable() called when not gated");

 
 

-    // closeGate is recursive so don't worry if we already hold the lock.
-    IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
-                       (unsigned int) action, (unsigned int) owner);
-
-    closeGate();
-    res = (*(Action) action)(owner, arg0, arg1, arg2, arg3);
-    openGate();
+    super::disable();
+}

 
 

-    return res;
+/* virtual */ void IOCommandGate::enable()
+{
+    if (workLoop) {
+       closeGate();
+       super::enable();
+       wakeupGate(&enabled, /* oneThread */ false); // Unblock sleeping threads
+       openGate();
+    }

 }
 
 }
 

-IOReturn IOCommandGate::runAction(Action inAction,
-                                  void *arg0 = 0, void *arg1 = 0,
-                                  void *arg2 = 0, void *arg3 = 0)
+/* virtual */ void IOCommandGate::free()

 {
 {

-    IOReturn res;
+    if (workLoop) setWorkLoop(0);
+    super::free();
+}

 
 

-    if (!enabled)
-        return kIOReturnNotPermitted;
+enum
+{
+    kSleepersRemoved     = 0x00000001,
+    kSleepersWaitEnabled = 0x00000002,
+    kSleepersActions     = 0x00000100,
+    kSleepersActionsMask = 0xffffff00,
+};

 
 

-    if (!inAction)
-        return kIOReturnBadArgument;
+/* virtual */ void IOCommandGate::setWorkLoop(IOWorkLoop *inWorkLoop)
+{
+    IOWorkLoop * wl;
+    uintptr_t  * sleepersP = (uintptr_t *) &reserved;
+    bool         defer;
+
+    if (!inWorkLoop && (wl = workLoop)) {              // tearing down
+       wl->closeGate();
+       *sleepersP |= kSleepersRemoved;
+       while (*sleepersP & kSleepersWaitEnabled) {
+           thread_wakeup_with_result(&enabled, THREAD_INTERRUPTED);
+           sleepGate(sleepersP, THREAD_UNINT);
+       }
+       *sleepersP &= ~kSleepersWaitEnabled;
+       defer = (0 != (kSleepersActionsMask & *sleepersP));
+       if (!defer)
+       {
+           super::setWorkLoop(0);
+           *sleepersP &= ~kSleepersRemoved;
+       }
+       wl->openGate();
+       return;
+    }

 
 

-    IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
-                       (unsigned int) inAction, (unsigned int) owner);
+    super::setWorkLoop(inWorkLoop);
+}

 
 

-    // closeGate is recursive so don't worry if we already hold the lock.
-    closeGate();
-    res = (*inAction)(owner, arg0, arg1, arg2, arg3);
-    openGate();
+IOReturn IOCommandGate::runCommand(void *arg0, void *arg1,
+                                   void *arg2, void *arg3)
+{
+    return runAction((Action) action, arg0, arg1, arg2, arg3);
+}

 
 

-    return res;
+IOReturn IOCommandGate::attemptCommand(void *arg0, void *arg1,
+                                       void *arg2, void *arg3)
+{
+    return attemptAction((Action) action, arg0, arg1, arg2, arg3);

 }
 
 }
 

-IOReturn IOCommandGate::attemptCommand(void *arg0 = 0, void *arg1 = 0,
-                                       void *arg2 = 0, void *arg3 = 0)
+IOReturn IOCommandGate::runAction(Action inAction,
+                                  void *arg0, void *arg1,
+                                  void *arg2, void *arg3)

 {
 {

-    IOReturn res;
+    IOWorkLoop * wl;
+    uintptr_t  * sleepersP;

 
 

-    if (!enabled)
-        return kIOReturnNotPermitted;
+    if (!inAction)
+        return kIOReturnBadArgument;
+    if (!(wl = workLoop))
+        return kIOReturnNotReady;

 
 

-    if (!action)
-        return kIOReturnNoResources;
+    // closeGate is recursive needn't worry if we already hold the lock.
+    wl->closeGate();
+    sleepersP = (uintptr_t *) &reserved;

 
 

-    // Try to hold the lock if can't get return immediately.
-    if (!tryCloseGate())
-        return kIOReturnCannotLock;
+    // If the command gate is disabled and we aren't on the workloop thread
+    // itself then sleep until we get enabled.
+    IOReturn res;
+    if (!wl->onThread())
+    {
+       while (!enabled)
+       {
+            IOReturn sleepResult = kIOReturnSuccess;
+           if (workLoop)
+           {
+               *sleepersP |= kSleepersWaitEnabled;
+               sleepResult = wl->sleepGate(&enabled, THREAD_INTERRUPTIBLE);
+               *sleepersP &= ~kSleepersWaitEnabled;
+           }
+           bool wakeupTearDown = (!workLoop || (0 != (*sleepersP & kSleepersRemoved)));
+           if ((kIOReturnSuccess != sleepResult) || wakeupTearDown) {
+               wl->openGate();
+
+                if (wakeupTearDown)
+                    wl->wakeupGate(sleepersP, false);  // No further resources used
+
+               return kIOReturnAborted;
+           }
+       }
+    }

 
 

-    // closeGate is recursive so don't worry if we already hold the lock.
-    IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
-                       (unsigned int) action, (unsigned int) owner);
+    bool trace = ( gIOKitTrace & kIOTraceCommandGates ) ? true : false;
+       
+    if (trace) IOTimeStampStartConstant(IODBG_CMDQ(IOCMDQ_ACTION),
+                                        VM_KERNEL_UNSLIDE(inAction), (uintptr_t) owner);
+       
+    IOStatisticsActionCall();
+       
+    // Must be gated and on the work loop or enabled

 
 

-    res = (*(Action) action)(owner, arg0, arg1, arg2, arg3);
-    openGate();
+    *sleepersP += kSleepersActions;
+    res = (*inAction)(owner, arg0, arg1, arg2, arg3);
+    *sleepersP -= kSleepersActions;
+
+    if (trace) IOTimeStampEndConstant(IODBG_CMDQ(IOCMDQ_ACTION),
+                                      VM_KERNEL_UNSLIDE(inAction), (uintptr_t) owner);

 
 

+    if (kSleepersRemoved == ((kSleepersActionsMask|kSleepersRemoved) & *sleepersP))
+    {
+        // no actions outstanding
+       *sleepersP &= ~kSleepersRemoved;
+       super::setWorkLoop(0);
+    }
+    
+    wl->openGate();
+       

     return res;
 }
 
 IOReturn IOCommandGate::attemptAction(Action inAction,
     return res;
 }
 
 IOReturn IOCommandGate::attemptAction(Action inAction,

-                                      void *arg0 = 0, void *arg1 = 0,
-                                      void *arg2 = 0, void *arg3 = 0)
+                                      void *arg0, void *arg1,
+                                      void *arg2, void *arg3)

 {
     IOReturn res;
 {
     IOReturn res;

-
-    if (!enabled)
-        return kIOReturnNotPermitted;
+    IOWorkLoop * wl;

 
     if (!inAction)
         return kIOReturnBadArgument;
 
     if (!inAction)
         return kIOReturnBadArgument;

+    if (!(wl = workLoop))
+        return kIOReturnNotReady;

 
     // Try to close the gate if can't get return immediately.
 
     // Try to close the gate if can't get return immediately.

-    if (!tryCloseGate())
+    if (!wl->tryCloseGate())

         return kIOReturnCannotLock;
 
         return kIOReturnCannotLock;
 

-    IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
-                       (unsigned int) inAction, (unsigned int) owner);
+    // If the command gate is disabled then sleep until we get a wakeup
+    if (!wl->onThread() && !enabled)
+        res = kIOReturnNotPermitted;
+    else {
+               
+        bool trace = ( gIOKitTrace & kIOTraceCommandGates ) ? true : false;
+               
+        if (trace)
+            IOTimeStampStartConstant(IODBG_CMDQ(IOCMDQ_ACTION),
+                                    VM_KERNEL_UNSLIDE(inAction), (uintptr_t) owner);
+        
+        IOStatisticsActionCall();
+        
+        res = (*inAction)(owner, arg0, arg1, arg2, arg3);
+               
+        if (trace)
+            IOTimeStampEndConstant(IODBG_CMDQ(IOCMDQ_ACTION),
+                                  VM_KERNEL_UNSLIDE(inAction), (uintptr_t) owner);
+    }

 
 

-    res = (*inAction)(owner, arg0, arg1, arg2, arg3);
-    openGate();
+    wl->openGate();

 
     return res;
 }
 
 IOReturn IOCommandGate::commandSleep(void *event, UInt32 interruptible)
 {
 
     return res;
 }
 
 IOReturn IOCommandGate::commandSleep(void *event, UInt32 interruptible)
 {

-    IOReturn ret;
-

     if (!workLoop->inGate())
         return kIOReturnNotPermitted;
 
     return sleepGate(event, interruptible);
 }
 
     if (!workLoop->inGate())
         return kIOReturnNotPermitted;
 
     return sleepGate(event, interruptible);
 }
 

+IOReturn IOCommandGate::commandSleep(void *event, AbsoluteTime deadline, UInt32 interruptible)
+{
+    if (!workLoop->inGate())
+        return kIOReturnNotPermitted;
+
+    return sleepGate(event, deadline, interruptible);
+}
+

 void IOCommandGate::commandWakeup(void *event, bool oneThread)
 {
     wakeupGate(event, oneThread);
 void IOCommandGate::commandWakeup(void *event, bool oneThread)
 {
     wakeupGate(event, oneThread);