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--- xnu/xnu-201.14/libkern/c++/OSObject.cpp
+++ xnu/xnu-1699.26.8/libkern/c++/OSObject.cpp
@@ -1,32 +1,44 @@
/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000 Apple Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * 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.
*
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * 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
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
*
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* OSObject.cpp created by gvdl on Fri 1998-11-17 */
#include <libkern/c++/OSObject.h>
+#include <libkern/c++/OSArray.h>
#include <libkern/c++/OSSerialize.h>
-#include <libkern/c++/OSSymbol.h>
#include <libkern/c++/OSLib.h>
+#include <libkern/OSDebug.h>
#include <libkern/c++/OSCPPDebug.h>
+#include <IOKit/IOKitDebug.h>
#include <libkern/OSAtomic.h>
+
+#include <libkern/c++/OSCollection.h>
+
+#include <kern/queue.h>
__BEGIN_DECLS
int debug_ivars_size;
@@ -74,25 +86,16 @@
OSMetaClassDefineReservedUnused(OSObject, 13);
OSMetaClassDefineReservedUnused(OSObject, 14);
OSMetaClassDefineReservedUnused(OSObject, 15);
-OSMetaClassDefineReservedUnused(OSObject, 16);
-OSMetaClassDefineReservedUnused(OSObject, 17);
-OSMetaClassDefineReservedUnused(OSObject, 18);
-OSMetaClassDefineReservedUnused(OSObject, 19);
-OSMetaClassDefineReservedUnused(OSObject, 20);
-OSMetaClassDefineReservedUnused(OSObject, 21);
-OSMetaClassDefineReservedUnused(OSObject, 22);
-OSMetaClassDefineReservedUnused(OSObject, 23);
-OSMetaClassDefineReservedUnused(OSObject, 24);
-OSMetaClassDefineReservedUnused(OSObject, 25);
-OSMetaClassDefineReservedUnused(OSObject, 26);
-OSMetaClassDefineReservedUnused(OSObject, 27);
-OSMetaClassDefineReservedUnused(OSObject, 28);
-OSMetaClassDefineReservedUnused(OSObject, 29);
-OSMetaClassDefineReservedUnused(OSObject, 30);
-OSMetaClassDefineReservedUnused(OSObject, 31);
-
-
-bool OSObject::init() { return true; }
+
+static const char *getClassName(const OSObject *obj)
+{
+ const OSMetaClass *meta = obj->getMetaClass();
+ return (meta) ? meta->getClassName() : "unknown class?";
+}
+
+bool OSObject::init()
+ { return true; }
+
void OSObject::free()
{
const OSMetaClass *meta = getMetaClass();
@@ -104,23 +107,136 @@
int OSObject::getRetainCount() const
{
- return retainCount;
+ return (int) ((UInt16) retainCount);
+}
+
+void OSObject::taggedRetain(const void *tag) const
+{
+ volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
+ UInt32 inc = 1;
+ UInt32 origCount;
+ UInt32 newCount;
+
+ // Increment the collection bucket.
+ if ((const void *) OSTypeID(OSCollection) == tag)
+ inc |= (1UL<<16);
+
+ do {
+ origCount = *countP;
+ if ( ((UInt16) origCount | 0x1) == 0xffff ) {
+ const char *msg;
+ if (origCount & 0x1) {
+ // If count == 0xffff that means we are freeing now so we can
+ // just return obviously somebody is cleaning up dangling
+ // references.
+ msg = "Attempting to retain a freed object";
+ }
+ else {
+ // If count == 0xfffe then we have wrapped our reference count.
+ // We should stop counting now as this reference must be
+ // leaked rather than accidently wrapping around the clock and
+ // freeing a very active object later.
+
+#if !DEBUG
+ break; // Break out of update loop which pegs the reference
+#else /* DEBUG */
+ // @@@ gvdl: eventually need to make this panic optional
+ // based on a boot argument i.e. debug= boot flag
+ msg = "About to wrap the reference count, reference leak?";
+#endif /* !DEBUG */
+ }
+ panic("OSObject::refcount: %s", msg);
+ }
+
+ newCount = origCount + inc;
+ } while (!OSCompareAndSwap(origCount, newCount, const_cast<UInt32 *>(countP)));
+}
+
+void OSObject::taggedRelease(const void *tag) const
+{
+ taggedRelease(tag, 1);
+}
+
+void OSObject::taggedRelease(const void *tag, const int when) const
+{
+ volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
+ UInt32 dec = 1;
+ UInt32 origCount;
+ UInt32 newCount;
+ UInt32 actualCount;
+
+ // Increment the collection bucket.
+ if ((const void *) OSTypeID(OSCollection) == tag)
+ dec |= (1UL<<16);
+
+ do {
+ origCount = *countP;
+
+ if ( ((UInt16) origCount | 0x1) == 0xffff ) {
+ if (origCount & 0x1) {
+ // If count == 0xffff that means we are freeing now so we can
+ // just return obviously somebody is cleaning up some dangling
+ // references. So we blow out immediately.
+ return;
+ }
+ else {
+ // If count == 0xfffe then we have wrapped our reference
+ // count. We should stop counting now as this reference must be
+ // leaked rather than accidently freeing an active object later.
+
+#if !DEBUG
+ return; // return out of function which pegs the reference
+#else /* DEBUG */
+ // @@@ gvdl: eventually need to make this panic optional
+ // based on a boot argument i.e. debug= boot flag
+ panic("OSObject::refcount: %s",
+ "About to unreference a pegged object, reference leak?");
+#endif /* !DEBUG */
+ }
+ }
+ actualCount = origCount - dec;
+ if ((UInt16) actualCount < when)
+ newCount = 0xffff;
+ else
+ newCount = actualCount;
+
+ } while (!OSCompareAndSwap(origCount, newCount, const_cast<UInt32 *>(countP)));
+
+ //
+ // This panic means that we have just attempted to release an object
+ // whose retain count has gone to less than the number of collections
+ // it is a member off. Take a panic immediately.
+ // In fact the panic MAY not be a registry corruption but it is
+ // ALWAYS the wrong thing to do. I call it a registry corruption 'cause
+ // the registry is the biggest single use of a network of collections.
+ //
+// xxx - this error message is overly-specific;
+// xxx - any code in the kernel could trip this,
+// xxx - and it applies as noted to all collections, not just the registry
+ if ((UInt16) actualCount < (actualCount >> 16)) {
+ panic("A kext releasing a(n) %s has corrupted the registry.",
+ getClassName(this));
+ }
+
+ // Check for a 'free' condition and that if we are first through
+ if (newCount == 0xffff) {
+ (const_cast<OSObject *>(this))->free();
+ }
+}
+
+void OSObject::release() const
+{
+ taggedRelease(0);
}
void OSObject::retain() const
{
- OSIncrementAtomic((SInt32 *) &retainCount);
+ taggedRetain(0);
}
void OSObject::release(int when) const
{
- if (OSDecrementAtomic((SInt32 *) &retainCount) <= when)
- ((OSObject *) this)->free();
-}
-
-void OSObject::release() const
-{
- release(1);
+ taggedRelease(0, when);
}
bool OSObject::serialize(OSSerialize *s) const
@@ -129,29 +245,97 @@
if (!s->addXMLStartTag(this, "string")) return false;
- const OSMetaClass *meta = getMetaClass();
- const char *className = (meta)? meta->getClassName() : "unknown class?";
-
- if (!s->addString(className)) return false;
+ if (!s->addString(getClassName(this))) return false;
if (!s->addString(" is not serializable")) return false;
return s->addXMLEndTag("string");
}
+
+thread_t gOSObjectTrackThread;
+
+queue_head_t gOSObjectTrackList =
+ { (queue_t) &gOSObjectTrackList, (queue_t) &gOSObjectTrackList };
+
+lck_spin_t gOSObjectTrackLock;
+
+OSArray * OSFlushObjectTrackList(void)
+{
+ OSArray * array;
+ queue_entry_t next;
+
+ array = OSArray::withCapacity(16);
+
+ lck_spin_lock(&gOSObjectTrackLock);
+ while (!queue_empty(&gOSObjectTrackList))
+ {
+ next = queue_first(&gOSObjectTrackList);
+ remque(next);
+ lck_spin_unlock(&gOSObjectTrackLock);
+ array->setObject((OSObject *) (next + 1));
+ lck_spin_lock(&gOSObjectTrackLock);
+ }
+ lck_spin_unlock(&gOSObjectTrackLock);
+
+ return (array);
+}
+
+struct OSObjectTracking
+{
+ queue_chain_t link;
+ void * bt[14];
+};
+
void *OSObject::operator new(size_t size)
{
- void *mem = (void *) kalloc(size);
+ size_t tracking = (gIOKitDebug & kOSTraceObjectAlloc)
+ ? sizeof(OSObjectTracking) : 0;
+ OSObjectTracking * mem = (OSObjectTracking *) kalloc(size + tracking);
+
assert(mem);
+
+ if (tracking)
+ {
+ if ((((thread_t) 1) == gOSObjectTrackThread) || (current_thread() == gOSObjectTrackThread))
+ {
+ (void) OSBacktrace(&mem->bt[0], sizeof(mem->bt) / sizeof(mem->bt[0]));
+ lck_spin_lock(&gOSObjectTrackLock);
+ enqueue_tail(&gOSObjectTrackList, &mem->link);
+ lck_spin_unlock(&gOSObjectTrackLock);
+ }
+ else
+ mem->link.next = 0;
+ mem++;
+ }
+
bzero(mem, size);
ACCUMSIZE(size);
- return mem;
-}
-
-void OSObject::operator delete(void *mem, size_t size)
-{
- kfree((vm_offset_t) mem, size);
+ return (void *) mem;
+}
+
+void OSObject::operator delete(void *_mem, size_t size)
+{
+ size_t tracking = (gIOKitDebug & kOSTraceObjectAlloc)
+ ? sizeof(OSObjectTracking) : 0;
+ OSObjectTracking * mem = (OSObjectTracking *) _mem;
+
+ if (!mem)
+ return;
+
+ if (tracking)
+ {
+ mem--;
+ if (mem->link.next)
+ {
+ lck_spin_lock(&gOSObjectTrackLock);
+ remque(&mem->link);
+ lck_spin_unlock(&gOSObjectTrackLock);
+ }
+ }
+
+ kfree(mem, size + tracking);
ACCUMSIZE(-size);
}