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iokit/Kernel/IOMemoryDescriptor.cpp xnu-12377.101.15 xnu-792
--- xnu/xnu-12377.101.15/iokit/Kernel/IOMemoryDescriptor.cpp
+++ xnu/xnu-792/iokit/Kernel/IOMemoryDescriptor.cpp
@@ -1,32 +1,31 @@
 /*
- * Copyright (c) 1998-2021 Apple Inc. All rights reserved.
+ * Copyright (c) 1998-2004 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
- * 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
+ * @APPLE_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 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, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
+/*
+ * Copyright (c) 1998 Apple Computer, Inc.  All rights reserved. 
  *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ * HISTORY
+ *
  */
-#define IOKIT_ENABLE_SHARED_PTR
-
+// 45678901234567890123456789012345678901234567890123456789012345678901234567890
 #include <sys/cdefs.h>
 
 #include <IOKit/assert.h>
@@ -34,92 +33,158 @@
 #include <IOKit/IOLib.h>
 #include <IOKit/IOMemoryDescriptor.h>
 #include <IOKit/IOMapper.h>
-#include <IOKit/IODMACommand.h>
 #include <IOKit/IOKitKeysPrivate.h>
 
-#include <IOKit/IOSubMemoryDescriptor.h>
-#include <IOKit/IOMultiMemoryDescriptor.h>
-#include <IOKit/IOBufferMemoryDescriptor.h>
-
 #include <IOKit/IOKitDebug.h>
-#include <IOKit/IOTimeStamp.h>
-#include <libkern/OSDebug.h>
-#include <libkern/OSKextLibPrivate.h>
 
 #include "IOKitKernelInternal.h"
 
-#include <libkern/c++/OSAllocation.h>
 #include <libkern/c++/OSContainers.h>
 #include <libkern/c++/OSDictionary.h>
 #include <libkern/c++/OSArray.h>
 #include <libkern/c++/OSSymbol.h>
 #include <libkern/c++/OSNumber.h>
-#include <os/overflow.h>
-#include <os/cpp_util.h>
-#include <os/base_private.h>
 
 #include <sys/uio.h>
 
 __BEGIN_DECLS
 #include <vm/pmap.h>
-#include <vm/vm_pageout_xnu.h>
+#include <vm/vm_pageout.h>
+#include <vm/vm_shared_memory_server.h>
 #include <mach/memory_object_types.h>
 #include <device/device_port.h>
 
+#ifndef i386
 #include <mach/vm_prot.h>
-#include <mach/mach_vm.h>
-#include <mach/memory_entry.h>
-#include <mach/mach_host.h>
-#include <vm/vm_fault_xnu.h>
-#include <vm/vm_protos.h>
-#include <vm/vm_memory_entry_xnu.h>
-#include <vm/vm_kern_xnu.h>
-#include <vm/vm_iokit.h>
-#include <vm/vm_map_xnu.h>
-#include <kern/thread.h>
-#if HAS_MTE
-#include <vm/vm_memtag.h>
-#endif /* HAS_MTE */
-#include <sys/vnode.h>
+#include <vm/vm_fault.h>
+struct phys_entry      *pmap_find_physentry(ppnum_t pa);
+#endif
 
 extern ppnum_t pmap_find_phys(pmap_t pmap, addr64_t va);
+void ipc_port_release_send(ipc_port_t port);
+
+/* Copy between a physical page and a virtual address in the given vm_map */
+kern_return_t copypv(addr64_t source, addr64_t sink, unsigned int size, int which);
+
+memory_object_t
+device_pager_setup(
+	memory_object_t	pager,
+	int		device_handle,
+	vm_size_t	size,
+	int		flags);
+void
+device_pager_deallocate(
+        memory_object_t);
+kern_return_t
+device_pager_populate_object(
+	memory_object_t		pager,
+	vm_object_offset_t	offset,
+	ppnum_t			phys_addr,
+	vm_size_t		size);
+kern_return_t
+memory_object_iopl_request(
+	ipc_port_t		port,
+	memory_object_offset_t	offset,
+	vm_size_t		*upl_size,
+	upl_t			*upl_ptr,
+	upl_page_info_array_t	user_page_list,
+	unsigned int		*page_list_count,
+	int			*flags);
+
+unsigned int  IOTranslateCacheBits(struct phys_entry *pp);
 
 __END_DECLS
 
-#define kIOMapperWaitSystem     ((IOMapper *) 1)
-
-static IOMapper * gIOSystemMapper = NULL;
-
-ppnum_t           gIOLastPage;
-
-enum {
-	kIOMapGuardSizeLarge = 65536
+#define kIOMaximumMappedIOByteCount	(512*1024*1024)
+
+static IOMapper * gIOSystemMapper;
+static ppnum_t	  gIOMaximumMappedIOPageCount = atop_32(kIOMaximumMappedIOByteCount);
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+OSDefineMetaClassAndAbstractStructors( IOMemoryDescriptor, OSObject )
+
+#define super IOMemoryDescriptor
+
+OSDefineMetaClassAndStructors(IOGeneralMemoryDescriptor, IOMemoryDescriptor)
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+static IORecursiveLock * gIOMemoryLock;
+
+#define LOCK	IORecursiveLockLock( gIOMemoryLock)
+#define UNLOCK	IORecursiveLockUnlock( gIOMemoryLock)
+#define SLEEP	IORecursiveLockSleep( gIOMemoryLock, (void *)this, THREAD_UNINT)
+#define WAKEUP	\
+    IORecursiveLockWakeup( gIOMemoryLock, (void *)this, /* one-thread */ false)
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+class _IOMemoryMap : public IOMemoryMap
+{
+    OSDeclareDefaultStructors(_IOMemoryMap)
+public:
+    IOMemoryDescriptor * memory;
+    IOMemoryMap *	superMap;
+    IOByteCount		offset;
+    IOByteCount		length;
+    IOVirtualAddress	logical;
+    task_t		addressTask;
+    vm_map_t		addressMap;
+    IOOptionBits	options;
+    upl_t		redirUPL;
+    ipc_port_t		redirEntry;
+    IOMemoryDescriptor * owner;
+
+protected:
+    virtual void taggedRelease(const void *tag = 0) const;
+    virtual void free();
+
+public:
+
+    // IOMemoryMap methods
+    virtual IOVirtualAddress 	getVirtualAddress();
+    virtual IOByteCount 	getLength();
+    virtual task_t		getAddressTask();
+    virtual IOMemoryDescriptor * getMemoryDescriptor();
+    virtual IOOptionBits 	getMapOptions();
+
+    virtual IOReturn 		unmap();
+    virtual void 		taskDied();
+
+    virtual IOReturn		redirect(IOMemoryDescriptor * newBackingMemory,
+					 IOOptionBits         options,
+					 IOByteCount          offset = 0);
+
+    virtual IOPhysicalAddress 	getPhysicalSegment(IOByteCount offset,
+	       					   IOByteCount * length);
+
+    // for IOMemoryDescriptor use
+    _IOMemoryMap * copyCompatible(
+		IOMemoryDescriptor *	owner,
+                task_t			intoTask,
+                IOVirtualAddress	toAddress,
+                IOOptionBits		options,
+                IOByteCount		offset,
+                IOByteCount		length );
+
+    bool initCompatible(
+	IOMemoryDescriptor *	memory,
+	IOMemoryMap *		superMap,
+        IOByteCount		offset,
+        IOByteCount		length );
+
+    bool initWithDescriptor(
+	IOMemoryDescriptor *	memory,
+	task_t			intoTask,
+	IOVirtualAddress	toAddress,
+	IOOptionBits		options,
+        IOByteCount		offset,
+        IOByteCount		length );
+
+    IOReturn redirect(
+	task_t			intoTask, bool redirect );
 };
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-OSDefineMetaClassAndAbstractStructors( IOMemoryDescriptor, OSObject )
-
-#define super IOMemoryDescriptor
-
-OSDefineMetaClassAndStructorsWithZone(IOGeneralMemoryDescriptor,
-    IOMemoryDescriptor, ZC_ZFREE_CLEARMEM)
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-static IORecursiveLock * gIOMemoryLock;
-
-#define LOCK    IORecursiveLockLock( gIOMemoryLock)
-#define UNLOCK  IORecursiveLockUnlock( gIOMemoryLock)
-#define SLEEP   IORecursiveLockSleep( gIOMemoryLock, (void *)this, THREAD_UNINT)
-#define WAKEUP  \
-    IORecursiveLockWakeup( gIOMemoryLock, (void *)this, /* one-thread */ false)
-
-#if 0
-#define DEBG(fmt, args...)      { kprintf(fmt, ## args); }
-#else
-#define DEBG(fmt, args...)      {}
-#endif
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
@@ -127,1933 +192,431 @@
 // Function
 
 enum ioPLBlockFlags {
-	kIOPLOnDevice  = 0x00000001,
-	kIOPLExternUPL = 0x00000002,
+    kIOPLOnDevice  = 0x00000001,
+    kIOPLExternUPL = 0x00000002,
 };
 
-struct IOMDPersistentInitData {
-	const IOGeneralMemoryDescriptor * fMD;
-	IOMemoryReference               * fMemRef;
+struct typePersMDData
+{
+    const IOGeneralMemoryDescriptor *fMD;
+    ipc_port_t fMemEntry;
 };
 
 struct ioPLBlock {
-	upl_t fIOPL;
-	vm_address_t fPageInfo; // Pointer to page list or index into it
-	uint64_t fIOMDOffset;       // The offset of this iopl in descriptor
-	ppnum_t fMappedPage;        // Page number of first page in this iopl
-	unsigned int fPageOffset;   // Offset within first page of iopl
-	unsigned int fFlags;        // Flags
+    upl_t fIOPL;
+    vm_address_t fIOMDOffset;	// The offset of this iopl in descriptor
+    vm_offset_t fPageInfo;	// Pointer to page list or index into it
+    ppnum_t fMappedBase;	// Page number of first page in this iopl
+    unsigned int fPageOffset;	// Offset within first page of iopl
+    unsigned int fFlags;	// Flags
 };
 
-enum { kMaxWireTags = 6 };
-
 struct ioGMDData {
-	IOMapper *  fMapper;
-	uint64_t    fDMAMapAlignment;
-	uint64_t    fMappedBase;
-	uint64_t    fMappedLength;
-	uint64_t    fPreparationID;
-#if IOTRACKING
-	IOTracking  fWireTracking;
-#endif /* IOTRACKING */
-	unsigned int      fPageCnt;
-	uint8_t           fDMAMapNumAddressBits;
-	unsigned char     fCompletionError:1;
-	unsigned char     fMappedBaseValid:1;
-	unsigned char     _resv:4;
-	unsigned char     fDMAAccess:2;
-
-	/* variable length arrays */
-	upl_page_info_t fPageList[1]
-#if __LP64__
-	// align fPageList as for ioPLBlock
-	__attribute__((aligned(sizeof(upl_t))))
-#endif
-	;
-	//ioPLBlock fBlocks[1];
+    IOMapper *fMapper;
+    unsigned int fPageCnt;
+    upl_page_info_t fPageList[];
+    ioPLBlock fBlocks[];
 };
 
-#pragma GCC visibility push(hidden)
-
-class _IOMemoryDescriptorMixedData : public OSObject
-{
-	OSDeclareDefaultStructors(_IOMemoryDescriptorMixedData);
-
-public:
-	static OSPtr<_IOMemoryDescriptorMixedData> withCapacity(size_t capacity);
-	bool initWithCapacity(size_t capacity);
-	virtual void free() APPLE_KEXT_OVERRIDE;
-
-	bool appendBytes(const void * bytes, size_t length);
-	bool setLength(size_t length);
-
-	const void * getBytes() const;
-	size_t getLength() const;
-
-private:
-	void freeMemory();
-
-	void *  _data = nullptr;
-	size_t  _length = 0;
-	size_t  _capacity = 0;
-};
-
-#pragma GCC visibility pop
-
-#define getDataP(osd)   ((ioGMDData *) (osd)->getBytes())
-#define getIOPLList(d)  ((ioPLBlock *) (void *)&(d->fPageList[d->fPageCnt]))
-#define getNumIOPL(osd, d)      \
-    ((UInt)(((osd)->getLength() - ((char *) getIOPLList(d) - (char *) d)) / sizeof(ioPLBlock)))
-#define getPageList(d)  (&(d->fPageList[0]))
+#define getDataP(osd)	((ioGMDData *) (osd)->getBytesNoCopy())
+#define getIOPLList(d)	((ioPLBlock *) &(d->fPageList[d->fPageCnt]))
+#define getNumIOPL(osd, d)	\
+    (((osd)->getLength() - ((char *) getIOPLList(d) - (char *) d)) / sizeof(ioPLBlock))
+#define getPageList(d)	(&(d->fPageList[0]))
 #define computeDataSize(p, u) \
-    (offsetof(ioGMDData, fPageList) + p * sizeof(upl_page_info_t) + u * sizeof(ioPLBlock))
-
-enum { kIOMemoryHostOrRemote = kIOMemoryHostOnly | kIOMemoryRemote };
+    (sizeof(ioGMDData) + p * sizeof(upl_page_info_t) + u * sizeof(ioPLBlock))
+
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
+#define next_page(a) ( trunc_page_32(a) + PAGE_SIZE )
+
+
 extern "C" {
-kern_return_t
-device_data_action(
-	uintptr_t               device_handle,
-	ipc_port_t              device_pager,
-	vm_prot_t               protection,
-	vm_object_offset_t      offset,
-	vm_size_t               size)
-{
-	kern_return_t        kr;
-	IOMemoryDescriptorReserved * ref = (IOMemoryDescriptorReserved *) device_handle;
-	OSSharedPtr<IOMemoryDescriptor> memDesc;
-
-	LOCK;
-	if (ref->dp.memory) {
-		memDesc.reset(ref->dp.memory, OSRetain);
-		kr = memDesc->handleFault(device_pager, offset, size);
-		memDesc.reset();
-	} else {
-		kr = KERN_ABORTED;
-	}
-	UNLOCK;
-
-	return kr;
-}
-
-kern_return_t
-device_close(
-	uintptr_t     device_handle)
-{
-	IOMemoryDescriptorReserved * ref = (IOMemoryDescriptorReserved *) device_handle;
-
-	IOFreeType( ref, IOMemoryDescriptorReserved );
-
-	return kIOReturnSuccess;
-}
-};      // end extern "C"
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+kern_return_t device_data_action(
+               int                     device_handle, 
+               ipc_port_t              device_pager,
+               vm_prot_t               protection, 
+               vm_object_offset_t      offset, 
+               vm_size_t               size)
+{
+    struct ExpansionData {
+        void *				devicePager;
+        unsigned int			pagerContig:1;
+        unsigned int			unused:31;
+	IOMemoryDescriptor *		memory;
+    };
+    kern_return_t	 kr;
+    ExpansionData *      ref = (ExpansionData *) device_handle;
+    IOMemoryDescriptor * memDesc;
+
+    LOCK;
+    memDesc = ref->memory;
+    if( memDesc)
+    {
+	memDesc->retain();
+	kr = memDesc->handleFault( device_pager, 0, 0,
+                offset, size, kIOMapDefaultCache /*?*/);
+	memDesc->release();
+    }
+    else
+	kr = KERN_ABORTED;
+    UNLOCK;
+
+    return( kr );
+}
+
+kern_return_t device_close(
+               int     device_handle)
+{
+    struct ExpansionData {
+        void *				devicePager;
+        unsigned int			pagerContig:1;
+        unsigned int			unused:31;
+	IOMemoryDescriptor *		memory;
+    };
+    ExpansionData *   ref = (ExpansionData *) device_handle;
+
+    IODelete( ref, ExpansionData, 1 );
+
+    return( kIOReturnSuccess );
+}
+};	// end extern "C"
 
 // Note this inline function uses C++ reference arguments to return values
 // This means that pointers are not passed and NULLs don't have to be
 // checked for as a NULL reference is illegal.
 static inline void
-getAddrLenForInd(
-	mach_vm_address_t                &addr,
-	mach_vm_size_t                   &len, // Output variables
-	UInt32                            type,
-	IOGeneralMemoryDescriptor::Ranges r,
-	UInt32                            ind,
-	task_t                            task __unused)
-{
-	assert(kIOMemoryTypeUIO == type || kIOMemoryTypeVnode == type
-	    || kIOMemoryTypeVirtual == type || kIOMemoryTypeVirtual64 == type
-	    || kIOMemoryTypePhysical == type || kIOMemoryTypePhysical64 == type);
-	if (kIOMemoryTypeUIO == type) {
-		user_size_t us;
-		user_addr_t ad;
-		uio_getiov((uio_t) r.uio, ind, &ad, &us); addr = ad; len = us;
-	}
-#ifndef __LP64__
-	else if ((kIOMemoryTypeVirtual64 == type) || (kIOMemoryTypePhysical64 == type)) {
-		IOAddressRange cur = r.v64[ind];
-		addr = cur.address;
-		len  = cur.length;
-	}
-#endif /* !__LP64__ */
-	else {
-		IOVirtualRange cur = r.v[ind];
-		addr = cur.address;
-		len  = cur.length;
-	}
+getAddrLenForInd(user_addr_t &addr, IOPhysicalLength &len, // Output variables
+     UInt32 type, IOGeneralMemoryDescriptor::Ranges r, UInt32 ind)
+{
+    assert(kIOMemoryTypePhysical == type || kIOMemoryTypeUIO == type
+	|| kIOMemoryTypeVirtual  == type);
+    if (kIOMemoryTypeUIO == type) {
+	user_size_t us;
+	uio_getiov((uio_t) r.uio, ind, &addr, &us); len = us;
+    }
+    else {
+	IOVirtualRange cur = r.v[ind];
+	addr = cur.address;
+	len  = cur.length;
+    }
 }
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-static IOReturn
-purgeableControlBits(IOOptionBits newState, vm_purgable_t * control, int * state)
-{
-	IOReturn err = kIOReturnSuccess;
-
-	*control = VM_PURGABLE_SET_STATE;
-
-	enum { kIOMemoryPurgeableControlMask = 15 };
-
-	switch (kIOMemoryPurgeableControlMask & newState) {
-	case kIOMemoryPurgeableKeepCurrent:
-		*control = VM_PURGABLE_GET_STATE;
-		break;
-
-	case kIOMemoryPurgeableNonVolatile:
-		*state = VM_PURGABLE_NONVOLATILE;
-		break;
-	case kIOMemoryPurgeableVolatile:
-		*state = VM_PURGABLE_VOLATILE | (newState & ~kIOMemoryPurgeableControlMask);
-		break;
-	case kIOMemoryPurgeableEmpty:
-		*state = VM_PURGABLE_EMPTY | (newState & ~kIOMemoryPurgeableControlMask);
-		break;
-	default:
-		err = kIOReturnBadArgument;
-		break;
-	}
-
-	if (*control == VM_PURGABLE_SET_STATE) {
-		// let VM know this call is from the kernel and is allowed to alter
-		// the volatility of the memory entry even if it was created with
-		// MAP_MEM_PURGABLE_KERNEL_ONLY
-		*control = VM_PURGABLE_SET_STATE_FROM_KERNEL;
-	}
-
-	return err;
-}
-
-static IOReturn
-purgeableStateBits(int * state)
-{
-	IOReturn err = kIOReturnSuccess;
-
-	switch (VM_PURGABLE_STATE_MASK & *state) {
-	case VM_PURGABLE_NONVOLATILE:
-		*state = kIOMemoryPurgeableNonVolatile;
-		break;
-	case VM_PURGABLE_VOLATILE:
-		*state = kIOMemoryPurgeableVolatile;
-		break;
-	case VM_PURGABLE_EMPTY:
-		*state = kIOMemoryPurgeableEmpty;
-		break;
-	default:
-		*state = kIOMemoryPurgeableNonVolatile;
-		err = kIOReturnNotReady;
-		break;
-	}
-	return err;
-}
-
-typedef struct {
-	unsigned int wimg;
-	unsigned int object_type;
-} iokit_memtype_entry;
-
-static const iokit_memtype_entry iomd_mem_types[] = {
-	[kIODefaultCache] = {VM_WIMG_DEFAULT, MAP_MEM_NOOP},
-	[kIOInhibitCache] = {VM_WIMG_IO, MAP_MEM_IO},
-	[kIOWriteThruCache] = {VM_WIMG_WTHRU, MAP_MEM_WTHRU},
-	[kIOWriteCombineCache] = {VM_WIMG_WCOMB, MAP_MEM_WCOMB},
-	[kIOCopybackCache] = {VM_WIMG_COPYBACK, MAP_MEM_COPYBACK},
-	[kIOCopybackInnerCache] = {VM_WIMG_INNERWBACK, MAP_MEM_INNERWBACK},
-	[kIOPostedWrite] = {VM_WIMG_POSTED, MAP_MEM_POSTED},
-	[kIORealTimeCache] = {VM_WIMG_RT, MAP_MEM_RT},
-	[kIOPostedReordered] = {VM_WIMG_POSTED_REORDERED, MAP_MEM_POSTED_REORDERED},
-	[kIOPostedCombinedReordered] = {VM_WIMG_POSTED_COMBINED_REORDERED, MAP_MEM_POSTED_COMBINED_REORDERED},
-};
-
-static vm_prot_t
-vmProtForCacheMode(IOOptionBits cacheMode)
-{
-	assert(cacheMode < (sizeof(iomd_mem_types) / sizeof(iomd_mem_types[0])));
-	if (cacheMode >= (sizeof(iomd_mem_types) / sizeof(iomd_mem_types[0]))) {
-		cacheMode = kIODefaultCache;
-	}
-	vm_prot_t prot = 0;
-	SET_MAP_MEM(iomd_mem_types[cacheMode].object_type, prot);
-	return prot;
-}
-
-static unsigned int
-pagerFlagsForCacheMode(IOOptionBits cacheMode)
-{
-	assert(cacheMode < (sizeof(iomd_mem_types) / sizeof(iomd_mem_types[0])));
-	if (cacheMode >= (sizeof(iomd_mem_types) / sizeof(iomd_mem_types[0]))) {
-		cacheMode = kIODefaultCache;
-	}
-	if (cacheMode == kIODefaultCache) {
-		return -1U;
-	}
-	return iomd_mem_types[cacheMode].wimg;
-}
-
-static IOOptionBits
-cacheModeForPagerFlags(unsigned int pagerFlags)
-{
-	pagerFlags &= VM_WIMG_MASK;
-	IOOptionBits cacheMode = kIODefaultCache;
-	for (IOOptionBits i = 0; i < (sizeof(iomd_mem_types) / sizeof(iomd_mem_types[0])); ++i) {
-		if (iomd_mem_types[i].wimg == pagerFlags) {
-			cacheMode = i;
-			break;
-		}
-	}
-	return (cacheMode == kIODefaultCache) ? kIOCopybackCache : cacheMode;
-}
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-struct IOMemoryEntry {
-	ipc_port_t entry;
-	int64_t    offset;
-	uint64_t   size;
-	uint64_t   start;
-};
-
-struct IOMemoryReference {
-	volatile SInt32             refCount;
-	vm_prot_t                   prot;
-	uint32_t                    capacity;
-	uint32_t                    count;
-	struct IOMemoryReference  * mapRef;
-	IOMemoryEntry               entries[0];
-};
-
-enum{
-	kIOMemoryReferenceReuse = 0x00000001,
-	kIOMemoryReferenceWrite = 0x00000002,
-	kIOMemoryReferenceCOW   = 0x00000004,
-};
-
-SInt32 gIOMemoryReferenceCount;
-
-IOMemoryReference *
-IOGeneralMemoryDescriptor::memoryReferenceAlloc(uint32_t capacity, IOMemoryReference * realloc)
-{
-	IOMemoryReference * ref;
-	size_t              oldCapacity;
-
-	if (realloc) {
-		oldCapacity = realloc->capacity;
-	} else {
-		oldCapacity = 0;
-	}
-
-	// Use the kalloc API instead of manually handling the reallocation
-	ref = krealloc_type(IOMemoryReference, IOMemoryEntry,
-	    oldCapacity, capacity, realloc, Z_WAITOK_ZERO);
-	if (ref) {
-		if (oldCapacity == 0) {
-			ref->refCount = 1;
-			OSIncrementAtomic(&gIOMemoryReferenceCount);
-		}
-		ref->capacity = capacity;
-	}
-	return ref;
-}
-
-void
-IOGeneralMemoryDescriptor::memoryReferenceFree(IOMemoryReference * ref)
-{
-	IOMemoryEntry * entries;
-
-	if (ref->mapRef) {
-		memoryReferenceFree(ref->mapRef);
-		ref->mapRef = NULL;
-	}
-
-	entries = ref->entries + ref->count;
-	while (entries > &ref->entries[0]) {
-		entries--;
-		mach_memory_entry_port_release(entries->entry);
-	}
-	kfree_type(IOMemoryReference, IOMemoryEntry, ref->capacity, ref);
-
-	OSDecrementAtomic(&gIOMemoryReferenceCount);
-}
-
-void
-IOGeneralMemoryDescriptor::memoryReferenceRelease(IOMemoryReference * ref)
-{
-	if (1 == OSDecrementAtomic(&ref->refCount)) {
-		memoryReferenceFree(ref);
-	}
-}
-
-vm_prot_t
-IOGeneralMemoryDescriptor::memoryReferenceProt(IOOptionBits options)
-{
-	vm_prot_t    prot;
-	IOOptionBits cacheMode;
-
-	// cache mode & vm_prot
-	prot = VM_PROT_READ;
-	cacheMode = ((_flags & kIOMemoryBufferCacheMask) >> kIOMemoryBufferCacheShift);
-	prot |= vmProtForCacheMode(cacheMode);
-	// VM system requires write access to change cache mode
-	if (kIODefaultCache != cacheMode) {
-		prot |= VM_PROT_WRITE;
-	}
-	if (kIODirectionOut != (kIODirectionOutIn & _flags)) {
-		prot |= VM_PROT_WRITE;
-	}
-	if (kIOMemoryReferenceWrite & options) {
-		prot |= VM_PROT_WRITE;
-	}
-	if (kIOMemoryReferenceCOW   & options) {
-		prot |= MAP_MEM_VM_COPY;
-	}
-	if (kIOMemoryUseReserve & _flags) {
-		prot |= MAP_MEM_GRAB_SECLUDED;
-	}
-	return prot;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::memoryReferenceCreate(
-	IOOptionBits         options,
-	ipc_port_t           entry,
-	uint64_t             offset,
-	uint64_t             size,
-	IOMemoryReference ** reference)
-{
-	IOMemoryReference     * ref;
-	vm_prot_t               prot;
-	memory_object_offset_ut mo_offset;
-
-	prot = memoryReferenceProt(options);
-	mo_offset = trunc_page(offset);
-	ref = memoryReferenceAlloc(1, NULL);
-	if (!ref) {
-		return kIOReturnNoMemory;
-	}
-	ref->entries[0].entry  = entry;
-	ref->prot              = prot | MAP_MEM_USE_DATA_ADDR;
-	ref->count             = 1;
-	ref->entries[0].size   = size + offset - mo_offset;             // entry starts at trunc_page
-	ref->entries[0].offset = mo_offset - offset;                    // so reference begins before offset zero
-
-	*reference = ref;
-
-	return kIOReturnSuccess;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::memoryReferenceCreate(
-	IOOptionBits         options,
-	IOMemoryReference ** reference)
-{
-	enum { kCapacity = 4, kCapacityInc = 4 };
-
-	kern_return_t        err;
-	IOMemoryReference *  ref;
-	IOMemoryEntry *      entries;
-	IOMemoryEntry *      cloneEntries = NULL;
-	vm_map_t             map;
-	ipc_port_t           entry, cloneEntry;
-	vm_prot_t            prot;
-	memory_object_size_t actualSize;
-	uint32_t             rangeIdx;
-	uint32_t             count;
-	mach_vm_address_t    entryAddr, endAddr, entrySize;
-	mach_vm_size_t       srcAddr, srcLen;
-	mach_vm_size_t       nextAddr, nextLen;
-	mach_vm_size_t       offset, remain;
-	vm_map_offset_t      overmap_start = 0, overmap_end = 0;
-	int                  misaligned_start = 0, misaligned_end = 0;
-	IOByteCount          physLen;
-	IOOptionBits         type = (_flags & kIOMemoryTypeMask);
-	unsigned int         pagerFlags;
-	vm_tag_t             tag;
-	vm_named_entry_kernel_flags_t vmne_kflags;
-
-	ref = memoryReferenceAlloc(kCapacity, NULL);
-	if (!ref) {
-		return kIOReturnNoMemory;
-	}
-
-	tag = (vm_tag_t) getVMTag(kernel_map);
-	vmne_kflags = VM_NAMED_ENTRY_KERNEL_FLAGS_NONE;
-	entries = &ref->entries[0];
-	count = 0;
-	err = KERN_SUCCESS;
-
-	offset = 0;
-	rangeIdx = 0;
-	remain = _length;
-	if (_task) {
-		getAddrLenForInd(nextAddr, nextLen, type, _ranges, rangeIdx, _task);
-
-		// account for IOBMD setLength(), use its capacity as length
-		IOBufferMemoryDescriptor * bmd;
-		if ((bmd = OSDynamicCast(IOBufferMemoryDescriptor, this))) {
-			nextLen = bmd->getCapacity();
-			remain  = nextLen;
-		}
-	} else {
-		nextAddr = getPhysicalSegment(offset, &physLen, kIOMemoryMapperNone);
-		nextLen = physLen;
-
-		// default cache mode for physical
-		if (kIODefaultCache == ((_flags & kIOMemoryBufferCacheMask) >> kIOMemoryBufferCacheShift)) {
-			IOOptionBits mode = cacheModeForPagerFlags(IODefaultCacheBits(nextAddr));
-			_flags |= (mode << kIOMemoryBufferCacheShift);
-		}
-	}
-
-	// cache mode & vm_prot
-	prot = memoryReferenceProt(options);
-
-	if ((kIOMemoryReferenceReuse & options) && _memRef) {
-		cloneEntries = &_memRef->entries[0];
-		prot |= MAP_MEM_NAMED_REUSE;
-	}
-
-	if (_task) {
-		// virtual ranges
-
-		if (kIOMemoryBufferPageable & _flags) {
-			int ledger_tag, ledger_no_footprint;
-
-			// IOBufferMemoryDescriptor alloc - set flags for entry + object create
-			prot |= MAP_MEM_NAMED_CREATE;
-
-			// default accounting settings:
-			//   + "none" ledger tag
-			//   + include in footprint
-			// can be changed later with ::setOwnership()
-			ledger_tag = VM_LEDGER_TAG_NONE;
-			ledger_no_footprint = 0;
-
-			if (kIOMemoryBufferPurgeable & _flags) {
-				prot |= (MAP_MEM_PURGABLE | MAP_MEM_PURGABLE_KERNEL_ONLY);
-				if (VM_KERN_MEMORY_SKYWALK == tag) {
-					// Skywalk purgeable memory accounting:
-					//    + "network" ledger tag
-					//    + not included in footprint
-					ledger_tag = VM_LEDGER_TAG_NETWORK;
-					ledger_no_footprint = 1;
-				} else {
-					// regular purgeable memory accounting:
-					//    + no ledger tag
-					//    + included in footprint
-					ledger_tag = VM_LEDGER_TAG_NONE;
-					ledger_no_footprint = 0;
-				}
-			}
-			vmne_kflags.vmnekf_ledger_tag = ledger_tag;
-			vmne_kflags.vmnekf_ledger_no_footprint = ledger_no_footprint;
-			if (kIOMemoryUseReserve & _flags) {
-				prot |= MAP_MEM_GRAB_SECLUDED;
-			}
-
-			prot |= VM_PROT_WRITE;
-			map = NULL;
-		} else {
-			prot |= MAP_MEM_USE_DATA_ADDR;
-			map = get_task_map(_task);
-		}
-		DEBUG4K_IOKIT("map %p _length 0x%llx prot 0x%x\n", map, (uint64_t)_length, prot);
-
-		while (remain) {
-			srcAddr  = nextAddr;
-			srcLen   = nextLen;
-			nextAddr = 0;
-			nextLen  = 0;
-			// coalesce addr range
-			for (++rangeIdx; rangeIdx < _rangesCount; rangeIdx++) {
-				getAddrLenForInd(nextAddr, nextLen, type, _ranges, rangeIdx, _task);
-				if ((srcAddr + srcLen) != nextAddr) {
-					break;
-				}
-				srcLen += nextLen;
-			}
-
-			if (MAP_MEM_USE_DATA_ADDR & prot) {
-				entryAddr = srcAddr;
-				endAddr   = srcAddr + srcLen;
-			} else {
-				entryAddr = trunc_page_64(srcAddr);
-				endAddr   = round_page_64(srcAddr + srcLen);
-			}
-			if (vm_map_page_mask(get_task_map(_task)) < PAGE_MASK) {
-				DEBUG4K_IOKIT("IOMemRef %p _flags 0x%x prot 0x%x _ranges[%d]: 0x%llx 0x%llx\n", ref, (uint32_t)_flags, prot, rangeIdx - 1, srcAddr, srcLen);
-			}
-
-			do{
-				entrySize = (endAddr - entryAddr);
-				if (!entrySize) {
-					break;
-				}
-				actualSize = entrySize;
-
-				cloneEntry = MACH_PORT_NULL;
-				if (MAP_MEM_NAMED_REUSE & prot) {
-					if (cloneEntries < &_memRef->entries[_memRef->count]) {
-						cloneEntry = cloneEntries->entry;
-					} else {
-						prot &= ~MAP_MEM_NAMED_REUSE;
-					}
-				}
-
-				mach_vm_offset_t entryAddrForVm = entryAddr;
-#if HAS_MTE
-				vmne_kflags.vmnekf_is_iokit = TRUE;
-				/* If we're holding a specific address and map, canonicalize the
-				 * address before passing it through to the VM.
-				 */
-				if (entryAddr != 0 && map != NULL) {
-					entryAddrForVm = vm_memtag_canonicalize(map, entryAddr);
-				}
-#endif /* HAS_MTE */
-				err = mach_make_memory_entry_internal(map,
-				    &actualSize, entryAddrForVm, prot, vmne_kflags, &entry, cloneEntry);
-
-				if (KERN_SUCCESS != err) {
-					DEBUG4K_ERROR("make_memory_entry(map %p, addr 0x%llx, size 0x%llx, prot 0x%x) err 0x%x\n", map, entryAddrForVm, actualSize, prot, err);
-					break;
-				}
-				if (MAP_MEM_USE_DATA_ADDR & prot) {
-					if (actualSize > entrySize) {
-						actualSize = entrySize;
-					}
-				} else if (actualSize > entrySize) {
-					panic("mach_make_memory_entry_64 actualSize");
-				}
-
-				memory_entry_check_for_adjustment(map, entry, &overmap_start, &overmap_end);
-
-				if (count && overmap_start) {
-					/*
-					 * Track misaligned start for all
-					 * except the first entry.
-					 */
-					misaligned_start++;
-				}
-
-				if (overmap_end) {
-					/*
-					 * Ignore misaligned end for the
-					 * last entry.
-					 */
-					if ((entryAddr + actualSize) != endAddr) {
-						misaligned_end++;
-					}
-				}
-
-				if (count) {
-					/* Middle entries */
-					if (misaligned_start || misaligned_end) {
-						DEBUG4K_IOKIT("stopped at entryAddr 0x%llx\n", entryAddr);
-						mach_memory_entry_port_release(entry);
-						err = KERN_NOT_SUPPORTED;
-						break;
-					}
-				}
-
-				if (count >= ref->capacity) {
-					ref = memoryReferenceAlloc(ref->capacity + kCapacityInc, ref);
-					entries = &ref->entries[count];
-				}
-				entries->entry  = entry;
-				entries->size   = actualSize;
-				entries->offset = offset + (entryAddr - srcAddr);
-				entries->start = entryAddr;
-				entryAddr += actualSize;
-				if (MAP_MEM_NAMED_REUSE & prot) {
-					if ((cloneEntries->entry == entries->entry)
-					    && (cloneEntries->size == entries->size)
-					    && (cloneEntries->offset == entries->offset)) {
-						cloneEntries++;
-					} else {
-						prot &= ~MAP_MEM_NAMED_REUSE;
-					}
-				}
-				entries++;
-				count++;
-			}while (true);
-			offset += srcLen;
-			remain -= srcLen;
-		}
-	} else {
-		// _task == 0, physical or kIOMemoryTypeUPL
-		memory_object_t pager;
-		vm_size_t       size = ptoa_64(_pages);
-
-		if (!getKernelReserved()) {
-			panic("getKernelReserved");
-		}
-
-		reserved->dp.pagerContig = (1 == _rangesCount);
-		reserved->dp.memory      = this;
-
-		IOOptionBits cacheMode;
-		cacheMode = ((_flags & kIOMemoryBufferCacheMask) >> kIOMemoryBufferCacheShift);
-		pagerFlags = pagerFlagsForCacheMode(cacheMode);
-		if (-1U == pagerFlags) {
-			panic("phys is kIODefaultCache");
-		}
-		if (reserved->dp.pagerContig) {
-			pagerFlags |= DEVICE_PAGER_CONTIGUOUS;
-		}
-
-		pager = device_pager_setup((memory_object_t) NULL, (uintptr_t) reserved,
-		    size, pagerFlags);
-		assert(pager);
-		if (!pager) {
-			DEBUG4K_ERROR("pager setup failed size 0x%llx flags 0x%x\n", (uint64_t)size, pagerFlags);
-			err = kIOReturnVMError;
-		} else {
-			srcAddr  = nextAddr;
-			entryAddr = trunc_page_64(srcAddr);
-			err = mach_memory_object_memory_entry_64((host_t) 1, false /*internal*/,
-			    size, VM_PROT_READ | VM_PROT_WRITE, pager, &entry);
-			assert(KERN_SUCCESS == err);
-			if (KERN_SUCCESS != err) {
-				device_pager_deallocate(pager);
-			} else {
-				reserved->dp.devicePager = pager;
-				entries->entry  = entry;
-				entries->size   = size;
-				entries->offset = offset + (entryAddr - srcAddr);
-				entries++;
-				count++;
-			}
-		}
-	}
-
-	ref->count = count;
-	ref->prot  = prot;
-
-	if (_task && (KERN_SUCCESS == err)
-	    && (kIOMemoryMapCopyOnWrite & _flags)
-	    && !(kIOMemoryReferenceCOW & options)) {
-		err = memoryReferenceCreate(options | kIOMemoryReferenceCOW, &ref->mapRef);
-		if (KERN_SUCCESS != err) {
-			DEBUG4K_ERROR("ref %p options 0x%x err 0x%x\n", ref, (unsigned int)options, err);
-		}
-	}
-
-	if (KERN_SUCCESS == err) {
-		if (MAP_MEM_NAMED_REUSE & prot) {
-			memoryReferenceFree(ref);
-			OSIncrementAtomic(&_memRef->refCount);
-			ref = _memRef;
-		}
-	} else {
-		DEBUG4K_ERROR("ref %p err 0x%x\n", ref, err);
-		memoryReferenceFree(ref);
-		ref = NULL;
-	}
-
-	*reference = ref;
-
-	return err;
-}
-
-static mach_vm_size_t
-IOMemoryDescriptorMapGuardSize(vm_map_t map, IOOptionBits options)
-{
-	switch (kIOMapGuardedMask & options) {
-	default:
-	case kIOMapGuardedSmall:
-		return vm_map_page_size(map);
-	case kIOMapGuardedLarge:
-		assert(0 == (kIOMapGuardSizeLarge & vm_map_page_mask(map)));
-		return kIOMapGuardSizeLarge;
-	}
-	;
-}
-
-static kern_return_t
-IOMemoryDescriptorMapDealloc(IOOptionBits options, vm_map_t map,
-    vm_map_offset_t addr, mach_vm_size_t size)
-{
-	kern_return_t   kr;
-	vm_map_offset_t actualAddr;
-	mach_vm_size_t  actualSize;
-
-	actualAddr = vm_map_trunc_page(addr, vm_map_page_mask(map));
-	actualSize = vm_map_round_page(addr + size, vm_map_page_mask(map)) - actualAddr;
-
-	if (kIOMapGuardedMask & options) {
-		mach_vm_size_t guardSize = IOMemoryDescriptorMapGuardSize(map, options);
-		actualAddr -= guardSize;
-		actualSize += 2 * guardSize;
-	}
-	kr = mach_vm_deallocate(map, actualAddr, actualSize);
-
-	return kr;
-}
-
-kern_return_t
-IOMemoryDescriptorMapAlloc(vm_map_t map, void * _ref)
-{
-	IOMemoryDescriptorMapAllocRef * ref = (typeof(ref))_ref;
-	IOReturn                        err;
-	vm_map_offset_t                 addr;
-	mach_vm_size_t                  size;
-	mach_vm_size_t                  guardSize;
-	vm_map_kernel_flags_t           vmk_flags;
-
-	addr = ref->mapped;
-	size = ref->size;
-	guardSize = 0;
-
-	if (kIOMapGuardedMask & ref->options) {
-		if (!(kIOMapAnywhere & ref->options)) {
-			return kIOReturnBadArgument;
-		}
-		guardSize = IOMemoryDescriptorMapGuardSize(map, ref->options);
-		size += 2 * guardSize;
-	}
-	if (kIOMapAnywhere & ref->options) {
-		vmk_flags = VM_MAP_KERNEL_FLAGS_ANYWHERE();
-	} else {
-		vmk_flags = VM_MAP_KERNEL_FLAGS_FIXED();
-	}
-	vmk_flags.vm_tag = ref->tag;
-
-	/*
-	 * Mapping memory into the kernel_map using IOMDs
-	 * use the shared data range.
-	 *
-	 * Memory being mapped should not contain kernel pointers.
-	 */
-	if (map == kernel_map) {
-		vmk_flags.vmkf_range_id = KMEM_RANGE_ID_DATA_SHARED;
-	}
-
-	err = mach_vm_map_kernel(map, &addr, size,
-#if __ARM_MIXED_PAGE_SIZE__
-	    // TODO4K this should not be necessary...
-	    (vm_map_offset_t)((ref->options & kIOMapAnywhere) ? IOMax(PAGE_MASK, vm_map_page_mask(map)) : 0),
-#else /* __ARM_MIXED_PAGE_SIZE__ */
-	    (vm_map_offset_t) 0,
-#endif /* __ARM_MIXED_PAGE_SIZE__ */
-	    vmk_flags,
-	    IPC_PORT_NULL,
-	    (memory_object_offset_t) 0,
-	    false,                       /* copy */
-	    ref->prot,
-	    ref->prot,
-	    VM_INHERIT_NONE);
-	if (KERN_SUCCESS == err) {
-		ref->mapped = (mach_vm_address_t) addr;
-		ref->map = map;
-		if (kIOMapGuardedMask & ref->options) {
-			vm_map_offset_t lastpage = vm_map_trunc_page(addr + size - guardSize, vm_map_page_mask(map));
-
-			err = mach_vm_protect(map, addr, guardSize, false /*set max*/, VM_PROT_NONE);
-			assert(KERN_SUCCESS == err);
-			err = mach_vm_protect(map, lastpage, guardSize, false /*set max*/, VM_PROT_NONE);
-			assert(KERN_SUCCESS == err);
-			ref->mapped += guardSize;
-		}
-	}
-
-	return err;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::memoryReferenceMap(
-	IOMemoryReference * ref,
-	vm_map_t            map,
-	mach_vm_size_t      inoffset,
-	mach_vm_size_t      size,
-	IOOptionBits        options,
-	mach_vm_address_t * inaddr)
-{
-	IOReturn        err;
-	int64_t         offset = inoffset;
-	uint32_t        rangeIdx, entryIdx;
-	vm_map_offset_t addr, mapAddr;
-	vm_map_offset_t pageOffset, entryOffset, remain, chunk;
-
-	mach_vm_address_t nextAddr;
-	mach_vm_size_t    nextLen;
-	IOByteCount       physLen;
-	IOMemoryEntry   * entry;
-	vm_prot_t         prot, memEntryCacheMode;
-	IOOptionBits      type;
-	IOOptionBits      cacheMode;
-	vm_tag_t          tag;
-	// for the kIOMapPrefault option.
-	upl_page_info_t * pageList = NULL;
-	UInt              currentPageIndex = 0;
-	bool              didAlloc;
-
-	DEBUG4K_IOKIT("ref %p map %p inoffset 0x%llx size 0x%llx options 0x%x *inaddr 0x%llx\n", ref, map, inoffset, size, (uint32_t)options, *inaddr);
-
-	if (ref->mapRef) {
-		err = memoryReferenceMap(ref->mapRef, map, inoffset, size, options, inaddr);
-		return err;
-	}
-
-	if (MAP_MEM_USE_DATA_ADDR & ref->prot) {
-		err = memoryReferenceMapNew(ref, map, inoffset, size, options, inaddr);
-		return err;
-	}
-
-	type = _flags & kIOMemoryTypeMask;
-
-	prot = VM_PROT_READ;
-	if (!(kIOMapReadOnly & options)) {
-		prot |= VM_PROT_WRITE;
-	}
-	prot &= ref->prot;
-
-	cacheMode = ((options & kIOMapCacheMask) >> kIOMapCacheShift);
-	if (kIODefaultCache != cacheMode) {
-		// VM system requires write access to update named entry cache mode
-		memEntryCacheMode = (MAP_MEM_ONLY | VM_PROT_WRITE | prot | vmProtForCacheMode(cacheMode));
-	}
-
-	tag = (typeof(tag))getVMTag(map);
-
-	if (_task) {
-		// Find first range for offset
-		if (!_rangesCount) {
-			return kIOReturnBadArgument;
-		}
-		for (remain = offset, rangeIdx = 0; rangeIdx < _rangesCount; rangeIdx++) {
-			getAddrLenForInd(nextAddr, nextLen, type, _ranges, rangeIdx, _task);
-			if (remain < nextLen) {
-				break;
-			}
-			remain -= nextLen;
-		}
-	} else {
-		rangeIdx = 0;
-		remain   = 0;
-		nextAddr = getPhysicalSegment(offset, &physLen, kIOMemoryMapperNone);
-		nextLen  = size;
-	}
-
-	assert(remain < nextLen);
-	if (remain >= nextLen) {
-		DEBUG4K_ERROR("map %p inoffset 0x%llx size 0x%llx options 0x%x inaddr 0x%llx remain 0x%llx nextLen 0x%llx\n", map, inoffset, size, (uint32_t)options, *inaddr, (uint64_t)remain, nextLen);
-		return kIOReturnBadArgument;
-	}
-
-	nextAddr  += remain;
-	nextLen   -= remain;
-#if __ARM_MIXED_PAGE_SIZE__
-	pageOffset = (vm_map_page_mask(map) & nextAddr);
-#else /* __ARM_MIXED_PAGE_SIZE__ */
-	pageOffset = (page_mask & nextAddr);
-#endif /* __ARM_MIXED_PAGE_SIZE__ */
-	addr       = 0;
-	didAlloc   = false;
-
-	if (!(options & kIOMapAnywhere)) {
-		addr = *inaddr;
-		if (pageOffset != (vm_map_page_mask(map) & addr)) {
-			DEBUG4K_ERROR("map %p inoffset 0x%llx size 0x%llx options 0x%x inaddr 0x%llx addr 0x%llx page_mask 0x%llx pageOffset 0x%llx\n", map, inoffset, size, (uint32_t)options, *inaddr, (uint64_t)addr, (uint64_t)page_mask, (uint64_t)pageOffset);
-		}
-		addr -= pageOffset;
-	}
-
-	// find first entry for offset
-	for (entryIdx = 0;
-	    (entryIdx < ref->count) && (offset >= ref->entries[entryIdx].offset);
-	    entryIdx++) {
-	}
-	entryIdx--;
-	entry = &ref->entries[entryIdx];
-
-	// allocate VM
-#if __ARM_MIXED_PAGE_SIZE__
-	size = round_page_mask_64(size + pageOffset, vm_map_page_mask(map));
-#else
-	size = round_page_64(size + pageOffset);
-#endif
-	if (kIOMapOverwrite & options) {
-		if ((map == kernel_map) && (kIOMemoryBufferPageable & _flags)) {
-			map = IOPageableMapForAddress(addr);
-		}
-		err = KERN_SUCCESS;
-	} else {
-		IOMemoryDescriptorMapAllocRef ref;
-		ref.map     = map;
-		ref.tag     = tag;
-		ref.options = options;
-		ref.size    = size;
-		ref.prot    = prot;
-		if (options & kIOMapAnywhere) {
-			// vm_map looks for addresses above here, even when VM_FLAGS_ANYWHERE
-			ref.mapped = 0;
-		} else {
-			ref.mapped = addr;
-		}
-		if ((ref.map == kernel_map) && (kIOMemoryBufferPageable & _flags)) {
-			err = IOIteratePageableMaps( ref.size, &IOMemoryDescriptorMapAlloc, &ref );
-		} else {
-			err = IOMemoryDescriptorMapAlloc(ref.map, &ref);
-		}
-		if (KERN_SUCCESS == err) {
-			addr     = ref.mapped;
-			map      = ref.map;
-			didAlloc = true;
-		}
-	}
-
-	/*
-	 * If the memory is associated with a device pager but doesn't have a UPL,
-	 * it will be immediately faulted in through the pager via populateDevicePager().
-	 * kIOMapPrefault is redundant in that case, so don't try to use it for UPL
-	 * operations.
-	 */
-	if ((reserved != NULL) && (reserved->dp.devicePager) && (_wireCount != 0)) {
-		options &= ~kIOMapPrefault;
-	}
-
-	/*
-	 * Prefaulting is only possible if we wired the memory earlier. Check the
-	 * memory type, and the underlying data.
-	 */
-	if (options & kIOMapPrefault) {
-		/*
-		 * The memory must have been wired by calling ::prepare(), otherwise
-		 * we don't have the UPL. Without UPLs, pages cannot be pre-faulted
-		 */
-		assert(_wireCount != 0);
-		assert(_memoryEntries != NULL);
-		if ((_wireCount == 0) ||
-		    (_memoryEntries == NULL)) {
-			DEBUG4K_ERROR("map %p inoffset 0x%llx size 0x%llx options 0x%x inaddr 0x%llx\n", map, inoffset, size, (uint32_t)options, *inaddr);
-			return kIOReturnBadArgument;
-		}
-
-		// Get the page list.
-		ioGMDData* dataP = getDataP(_memoryEntries);
-		ioPLBlock const* ioplList = getIOPLList(dataP);
-		pageList = getPageList(dataP);
-
-		// Get the number of IOPLs.
-		UInt numIOPLs = getNumIOPL(_memoryEntries, dataP);
-
-		/*
-		 * Scan through the IOPL Info Blocks, looking for the first block containing
-		 * the offset. The research will go past it, so we'll need to go back to the
-		 * right range at the end.
-		 */
-		UInt ioplIndex = 0;
-		while ((ioplIndex < numIOPLs) && (((uint64_t) offset) >= ioplList[ioplIndex].fIOMDOffset)) {
-			ioplIndex++;
-		}
-		ioplIndex--;
-
-		// Retrieve the IOPL info block.
-		ioPLBlock ioplInfo = ioplList[ioplIndex];
-
-		/*
-		 * For external UPLs, the fPageInfo points directly to the UPL's page_info_t
-		 * array.
-		 */
-		if (ioplInfo.fFlags & kIOPLExternUPL) {
-			pageList = (upl_page_info_t*) ioplInfo.fPageInfo;
-		} else {
-			pageList = &pageList[ioplInfo.fPageInfo];
-		}
-
-		// Rebase [offset] into the IOPL in order to looks for the first page index.
-		mach_vm_size_t offsetInIOPL = offset - ioplInfo.fIOMDOffset + ioplInfo.fPageOffset;
-
-		// Retrieve the index of the first page corresponding to the offset.
-		currentPageIndex = atop_32(offsetInIOPL);
-	}
-
-	// enter mappings
-	remain  = size;
-	mapAddr = addr;
-	addr    += pageOffset;
-
-	while (remain && (KERN_SUCCESS == err)) {
-		entryOffset = offset - entry->offset;
-		if ((IOMin(vm_map_page_mask(map), page_mask) & entryOffset) != pageOffset) {
-			err = kIOReturnNotAligned;
-			DEBUG4K_ERROR("map %p inoffset 0x%llx size 0x%llx options 0x%x inaddr 0x%llx entryOffset 0x%llx pageOffset 0x%llx\n", map, inoffset, size, (uint32_t)options, *inaddr, (uint64_t)entryOffset, (uint64_t)pageOffset);
-			break;
-		}
-
-		if (kIODefaultCache != cacheMode) {
-			vm_size_t unused = 0;
-			err = mach_make_memory_entry(NULL /*unused*/, &unused, 0 /*unused*/,
-			    memEntryCacheMode, NULL, entry->entry);
-			assert(KERN_SUCCESS == err);
-		}
-
-		entryOffset -= pageOffset;
-		if (entryOffset >= entry->size) {
-			panic("entryOffset");
-		}
-		chunk = entry->size - entryOffset;
-		if (chunk) {
-			vm_map_kernel_flags_t vmk_flags = {
-				.vmf_fixed = true,
-				.vmf_overwrite = true,
-				.vm_tag = tag,
-				.vmkf_iokit_acct = true,
-			};
-
-			if (chunk > remain) {
-				chunk = remain;
-			}
-			if (options & kIOMapPrefault) {
-				UInt nb_pages = (typeof(nb_pages))round_page(chunk) / PAGE_SIZE;
-
-				err = vm_map_enter_mem_object_prefault(map,
-				    &mapAddr,
-				    chunk, 0 /* mask */,
-				    vmk_flags,
-				    entry->entry,
-				    entryOffset,
-				    prot,                        // cur
-				    prot,                        // max
-				    &pageList[currentPageIndex],
-				    nb_pages);
-
-				if (err || vm_map_page_mask(map) < PAGE_MASK) {
-					DEBUG4K_IOKIT("IOMemRef %p mapped in map %p (pgshift %d) at 0x%llx size 0x%llx err 0x%x\n", ref, map, vm_map_page_shift(map), (uint64_t)mapAddr, (uint64_t)chunk, err);
-				}
-				// Compute the next index in the page list.
-				currentPageIndex += nb_pages;
-				assert(currentPageIndex <= _pages);
-			} else {
-				err = mach_vm_map_kernel(map,
-				    &mapAddr,
-				    chunk, 0 /* mask */,
-				    vmk_flags,
-				    entry->entry,
-				    entryOffset,
-				    false,               // copy
-				    prot,               // cur
-				    prot,               // max
-				    VM_INHERIT_NONE);
-			}
-			if (KERN_SUCCESS != err) {
-				DEBUG4K_ERROR("IOMemRef %p mapped in map %p (pgshift %d) at 0x%llx size 0x%llx err 0x%x\n", ref, map, vm_map_page_shift(map), (uint64_t)mapAddr, (uint64_t)chunk, err);
-				break;
-			}
-			remain -= chunk;
-			if (!remain) {
-				break;
-			}
-			mapAddr  += chunk;
-			offset   += chunk - pageOffset;
-		}
-		pageOffset = 0;
-		entry++;
-		entryIdx++;
-		if (entryIdx >= ref->count) {
-			err = kIOReturnOverrun;
-			DEBUG4K_ERROR("map %p inoffset 0x%llx size 0x%llx options 0x%x inaddr 0x%llx entryIdx %d ref->count %d\n", map, inoffset, size, (uint32_t)options, *inaddr, entryIdx, ref->count);
-			break;
-		}
-	}
-
-	if ((KERN_SUCCESS != err) && didAlloc) {
-		(void) IOMemoryDescriptorMapDealloc(options, map, trunc_page_64(addr), size);
-		addr = 0;
-	}
-	*inaddr = addr;
-
-	if (err /* || vm_map_page_mask(map) < PAGE_MASK */) {
-		DEBUG4K_ERROR("map %p (%d) inoffset 0x%llx size 0x%llx options 0x%x inaddr 0x%llx err 0x%x\n", map, vm_map_page_shift(map), inoffset, size, (uint32_t)options, *inaddr, err);
-	}
-	return err;
-}
-
-#define LOGUNALIGN 0
-IOReturn
-IOGeneralMemoryDescriptor::memoryReferenceMapNew(
-	IOMemoryReference * ref,
-	vm_map_t            map,
-	mach_vm_size_t      inoffset,
-	mach_vm_size_t      size,
-	IOOptionBits        options,
-	mach_vm_address_t * inaddr)
-{
-	IOReturn            err;
-	int64_t             offset = inoffset;
-	uint32_t            entryIdx, firstEntryIdx;
-	vm_map_offset_t     addr, mapAddr, mapAddrOut;
-	vm_map_offset_t     entryOffset, remain, chunk;
-
-	IOMemoryEntry    * entry;
-	vm_prot_t          prot, memEntryCacheMode;
-	IOOptionBits       type;
-	IOOptionBits       cacheMode;
-	vm_tag_t           tag;
-	// for the kIOMapPrefault option.
-	upl_page_info_t  * pageList = NULL;
-	UInt               currentPageIndex = 0;
-	bool               didAlloc;
-
-	DEBUG4K_IOKIT("ref %p map %p inoffset 0x%llx size 0x%llx options 0x%x *inaddr 0x%llx\n", ref, map, inoffset, size, (uint32_t)options, *inaddr);
-
-	if (ref->mapRef) {
-		err = memoryReferenceMap(ref->mapRef, map, inoffset, size, options, inaddr);
-		return err;
-	}
-
-#if LOGUNALIGN
-	printf("MAP offset %qx, %qx\n", inoffset, size);
-#endif
-
-	type = _flags & kIOMemoryTypeMask;
-
-	prot = VM_PROT_READ;
-	if (!(kIOMapReadOnly & options)) {
-		prot |= VM_PROT_WRITE;
-	}
-	prot &= ref->prot;
-
-	cacheMode = ((options & kIOMapCacheMask) >> kIOMapCacheShift);
-	if (kIODefaultCache != cacheMode) {
-		// VM system requires write access to update named entry cache mode
-		memEntryCacheMode = (MAP_MEM_ONLY | VM_PROT_WRITE | prot | vmProtForCacheMode(cacheMode));
-	}
-
-	tag = (vm_tag_t) getVMTag(map);
-
-	addr       = 0;
-	didAlloc   = false;
-
-	if (!(options & kIOMapAnywhere)) {
-		addr = *inaddr;
-	}
-
-	// find first entry for offset
-	for (firstEntryIdx = 0;
-	    (firstEntryIdx < ref->count) && (offset >= ref->entries[firstEntryIdx].offset);
-	    firstEntryIdx++) {
-	}
-	firstEntryIdx--;
-
-	// calculate required VM space
-
-	entryIdx = firstEntryIdx;
-	entry = &ref->entries[entryIdx];
-
-	remain  = size;
-	int64_t iteroffset = offset;
-	uint64_t mapSize = 0;
-	while (remain) {
-		entryOffset = iteroffset - entry->offset;
-		if (entryOffset >= entry->size) {
-			panic("entryOffset");
-		}
-
-#if LOGUNALIGN
-		printf("[%d] size %qx offset %qx start %qx iter %qx\n",
-		    entryIdx, entry->size, entry->offset, entry->start, iteroffset);
-#endif
-
-		chunk = entry->size - entryOffset;
-		if (chunk) {
-			if (chunk > remain) {
-				chunk = remain;
-			}
-			mach_vm_size_t entrySize;
-			err = mach_memory_entry_map_size(entry->entry, map, entryOffset, chunk, &entrySize);
-			assert(KERN_SUCCESS == err);
-			mapSize += entrySize;
-
-			remain -= chunk;
-			if (!remain) {
-				break;
-			}
-			iteroffset   += chunk; // - pageOffset;
-		}
-		entry++;
-		entryIdx++;
-		if (entryIdx >= ref->count) {
-			panic("overrun");
-			err = kIOReturnOverrun;
-			break;
-		}
-	}
-
-	if (kIOMapOverwrite & options) {
-		if ((map == kernel_map) && (kIOMemoryBufferPageable & _flags)) {
-			map = IOPageableMapForAddress(addr);
-		}
-		err = KERN_SUCCESS;
-	} else {
-		IOMemoryDescriptorMapAllocRef ref;
-		ref.map     = map;
-		ref.tag     = tag;
-		ref.options = options;
-		ref.size    = mapSize;
-		ref.prot    = prot;
-		if (options & kIOMapAnywhere) {
-			// vm_map looks for addresses above here, even when VM_FLAGS_ANYWHERE
-			ref.mapped = 0;
-		} else {
-			ref.mapped = addr;
-		}
-		if ((ref.map == kernel_map) && (kIOMemoryBufferPageable & _flags)) {
-			err = IOIteratePageableMaps( ref.size, &IOMemoryDescriptorMapAlloc, &ref );
-		} else {
-			err = IOMemoryDescriptorMapAlloc(ref.map, &ref);
-		}
-
-		if (KERN_SUCCESS == err) {
-			addr     = ref.mapped;
-			map      = ref.map;
-			didAlloc = true;
-		}
-#if LOGUNALIGN
-		IOLog("map err %x size %qx addr %qx\n", err, mapSize, addr);
-#endif
-	}
-
-	/*
-	 * If the memory is associated with a device pager but doesn't have a UPL,
-	 * it will be immediately faulted in through the pager via populateDevicePager().
-	 * kIOMapPrefault is redundant in that case, so don't try to use it for UPL
-	 * operations.
-	 */
-	if ((reserved != NULL) && (reserved->dp.devicePager) && (_wireCount != 0)) {
-		options &= ~kIOMapPrefault;
-	}
-
-	/*
-	 * Prefaulting is only possible if we wired the memory earlier. Check the
-	 * memory type, and the underlying data.
-	 */
-	if (options & kIOMapPrefault) {
-		/*
-		 * The memory must have been wired by calling ::prepare(), otherwise
-		 * we don't have the UPL. Without UPLs, pages cannot be pre-faulted
-		 */
-		assert(_wireCount != 0);
-		assert(_memoryEntries != NULL);
-		if ((_wireCount == 0) ||
-		    (_memoryEntries == NULL)) {
-			return kIOReturnBadArgument;
-		}
-
-		// Get the page list.
-		ioGMDData* dataP = getDataP(_memoryEntries);
-		ioPLBlock const* ioplList = getIOPLList(dataP);
-		pageList = getPageList(dataP);
-
-		// Get the number of IOPLs.
-		UInt numIOPLs = getNumIOPL(_memoryEntries, dataP);
-
-		/*
-		 * Scan through the IOPL Info Blocks, looking for the first block containing
-		 * the offset. The research will go past it, so we'll need to go back to the
-		 * right range at the end.
-		 */
-		UInt ioplIndex = 0;
-		while ((ioplIndex < numIOPLs) && (((uint64_t) offset) >= ioplList[ioplIndex].fIOMDOffset)) {
-			ioplIndex++;
-		}
-		ioplIndex--;
-
-		// Retrieve the IOPL info block.
-		ioPLBlock ioplInfo = ioplList[ioplIndex];
-
-		/*
-		 * For external UPLs, the fPageInfo points directly to the UPL's page_info_t
-		 * array.
-		 */
-		if (ioplInfo.fFlags & kIOPLExternUPL) {
-			pageList = (upl_page_info_t*) ioplInfo.fPageInfo;
-		} else {
-			pageList = &pageList[ioplInfo.fPageInfo];
-		}
-
-		// Rebase [offset] into the IOPL in order to looks for the first page index.
-		mach_vm_size_t offsetInIOPL = offset - ioplInfo.fIOMDOffset + ioplInfo.fPageOffset;
-
-		// Retrieve the index of the first page corresponding to the offset.
-		currentPageIndex = atop_32(offsetInIOPL);
-	}
-
-	// enter mappings
-	remain   = size;
-	mapAddr  = addr;
-	entryIdx = firstEntryIdx;
-	entry = &ref->entries[entryIdx];
-
-	while (remain && (KERN_SUCCESS == err)) {
-#if LOGUNALIGN
-		printf("offset %qx, %qx\n", offset, entry->offset);
-#endif
-		if (kIODefaultCache != cacheMode) {
-			vm_size_t unused = 0;
-			err = mach_make_memory_entry(NULL /*unused*/, &unused, 0 /*unused*/,
-			    memEntryCacheMode, NULL, entry->entry);
-			assert(KERN_SUCCESS == err);
-		}
-		entryOffset = offset - entry->offset;
-		if (entryOffset >= entry->size) {
-			panic("entryOffset");
-		}
-		chunk = entry->size - entryOffset;
-#if LOGUNALIGN
-		printf("entryIdx %d, chunk %qx\n", entryIdx, chunk);
-#endif
-		if (chunk) {
-			vm_map_kernel_flags_t vmk_flags = {
-				.vmf_fixed = true,
-				.vmf_overwrite = true,
-				.vmf_return_data_addr = true,
-				.vm_tag = tag,
-				.vmkf_iokit_acct = true,
-			};
-
-			if (chunk > remain) {
-				chunk = remain;
-			}
-			mapAddrOut = mapAddr;
-			if (options & kIOMapPrefault) {
-				UInt nb_pages = (typeof(nb_pages))round_page(chunk) / PAGE_SIZE;
-
-				err = vm_map_enter_mem_object_prefault(map,
-				    &mapAddrOut,
-				    chunk, 0 /* mask */,
-				    vmk_flags,
-				    entry->entry,
-				    entryOffset,
-				    prot,                        // cur
-				    prot,                        // max
-				    &pageList[currentPageIndex],
-				    nb_pages);
-
-				// Compute the next index in the page list.
-				currentPageIndex += nb_pages;
-				assert(currentPageIndex <= _pages);
-			} else {
-#if LOGUNALIGN
-				printf("mapAddr i %qx chunk %qx\n", mapAddr, chunk);
-#endif
-#if HAS_MTE
-				/* The memory that originated this IOMD might've been MTE-enabled,
-				 * so we need to inform the VM that MTE policies apply.
-				 */
-				vmk_flags.vmf_mte = true;
-				vmk_flags.vmkf_is_iokit = true;
-#endif /* HAS_MTE */
-				err = mach_vm_map_kernel(map,
-				    &mapAddrOut,
-				    chunk, 0 /* mask */,
-				    vmk_flags,
-				    entry->entry,
-				    entryOffset,
-				    false,               // copy
-				    prot,               // cur
-				    prot,               // max
-				    VM_INHERIT_NONE);
-			}
-			if (KERN_SUCCESS != err) {
-				panic("map enter err %x", err);
-				break;
-			}
-#if LOGUNALIGN
-			printf("mapAddr o %qx\n", mapAddrOut);
-#endif
-			if (entryIdx == firstEntryIdx) {
-				addr = mapAddrOut;
-			}
-			remain -= chunk;
-			if (!remain) {
-				break;
-			}
-			mach_vm_size_t entrySize;
-			err = mach_memory_entry_map_size(entry->entry, map, entryOffset, chunk, &entrySize);
-			assert(KERN_SUCCESS == err);
-			mapAddr += entrySize;
-			offset  += chunk;
-		}
-
-		entry++;
-		entryIdx++;
-		if (entryIdx >= ref->count) {
-			err = kIOReturnOverrun;
-			break;
-		}
-	}
-
-	if (KERN_SUCCESS != err) {
-		DEBUG4K_ERROR("size 0x%llx err 0x%x\n", size, err);
-	}
-
-	if ((KERN_SUCCESS != err) && didAlloc) {
-		(void) IOMemoryDescriptorMapDealloc(options, map, trunc_page_64(addr), size);
-		addr = 0;
-	}
-	*inaddr = addr;
-
-	return err;
-}
-
-uint64_t
-IOGeneralMemoryDescriptor::memoryReferenceGetDMAMapLength(
-	IOMemoryReference * ref,
-	uint64_t          * offset)
-{
-	kern_return_t kr;
-	vm_object_offset_t data_offset = 0;
-	uint64_t total;
-	uint32_t idx;
-
-	assert(ref->count);
-	if (offset) {
-		*offset = (uint64_t) data_offset;
-	}
-	total = 0;
-	for (idx = 0; idx < ref->count; idx++) {
-		kr = mach_memory_entry_phys_page_offset(ref->entries[idx].entry,
-		    &data_offset);
-		if (KERN_SUCCESS != kr) {
-			DEBUG4K_ERROR("ref %p entry %p kr 0x%x\n", ref, ref->entries[idx].entry, kr);
-		} else if (0 != data_offset) {
-			DEBUG4K_IOKIT("ref %p entry %p offset 0x%llx kr 0x%x\n", ref, ref->entries[0].entry, data_offset, kr);
-		}
-		if (offset && !idx) {
-			*offset = (uint64_t) data_offset;
-		}
-		total += round_page(data_offset + ref->entries[idx].size);
-	}
-
-	DEBUG4K_IOKIT("ref %p offset 0x%llx total 0x%llx\n", ref,
-	    (offset ? *offset : (vm_object_offset_t)-1), total);
-
-	return total;
-}
-
-
-IOReturn
-IOGeneralMemoryDescriptor::memoryReferenceGetPageCounts(
-	IOMemoryReference * ref,
-	IOByteCount       * residentPageCount,
-	IOByteCount       * dirtyPageCount,
-	IOByteCount       * swappedPageCount)
-{
-	IOReturn        err;
-	IOMemoryEntry * entries;
-	UInt64 resident, dirty, swapped;
-	UInt64 totalResident, totalDirty, totalSwapped;
-
-	totalResident = totalDirty = totalSwapped = 0;
-	err = kIOReturnSuccess;
-	entries = ref->entries + ref->count;
-	while (entries > &ref->entries[0]) {
-		entries--;
-		err = mach_memory_entry_get_page_counts(entries->entry, &resident, &dirty, &swapped);
-		if (KERN_SUCCESS != err) {
-			break;
-		}
-		totalResident += resident;
-		totalDirty    += dirty;
-		totalSwapped  += swapped;
-	}
-
-	if (residentPageCount) {
-		*residentPageCount = totalResident;
-	}
-	if (dirtyPageCount) {
-		*dirtyPageCount    = totalDirty;
-	}
-	if (swappedPageCount) {
-		*swappedPageCount  = totalSwapped;
-	}
-	return err;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::memoryReferenceSetPurgeable(
-	IOMemoryReference * ref,
-	IOOptionBits        newState,
-	IOOptionBits      * oldState)
-{
-	IOReturn        err;
-	IOMemoryEntry * entries;
-	vm_purgable_t   control;
-	int             totalState, state;
-
-	totalState = kIOMemoryPurgeableNonVolatile;
-	err = kIOReturnSuccess;
-	entries = ref->entries + ref->count;
-	while (entries > &ref->entries[0]) {
-		entries--;
-
-		err = purgeableControlBits(newState, &control, &state);
-		if (KERN_SUCCESS != err) {
-			break;
-		}
-		err = memory_entry_purgeable_control_internal(entries->entry, control, &state);
-		if (KERN_SUCCESS != err) {
-			break;
-		}
-		err = purgeableStateBits(&state);
-		if (KERN_SUCCESS != err) {
-			break;
-		}
-
-		if (kIOMemoryPurgeableEmpty == state) {
-			totalState = kIOMemoryPurgeableEmpty;
-		} else if (kIOMemoryPurgeableEmpty == totalState) {
-			continue;
-		} else if (kIOMemoryPurgeableVolatile == totalState) {
-			continue;
-		} else if (kIOMemoryPurgeableVolatile == state) {
-			totalState = kIOMemoryPurgeableVolatile;
-		} else {
-			totalState = kIOMemoryPurgeableNonVolatile;
-		}
-	}
-
-	if (oldState) {
-		*oldState = totalState;
-	}
-	return err;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::memoryReferenceSetOwnership(
-	IOMemoryReference * ref,
-	task_t              newOwner,
-	int                 newLedgerTag,
-	IOOptionBits        newLedgerOptions)
-{
-	IOReturn        err, totalErr;
-	IOMemoryEntry * entries;
-
-	totalErr = kIOReturnSuccess;
-	entries = ref->entries + ref->count;
-	while (entries > &ref->entries[0]) {
-		entries--;
-
-		err = mach_memory_entry_ownership(entries->entry, newOwner, newLedgerTag, newLedgerOptions);
-		if (KERN_SUCCESS != err) {
-			totalErr = err;
-		}
-	}
-
-	return totalErr;
-}
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-OSSharedPtr<IOMemoryDescriptor>
+/*
+ * withAddress:
+ *
+ * Create a new IOMemoryDescriptor.  The buffer is a virtual address
+ * relative to the specified task.  If no task is supplied, the kernel
+ * task is implied.
+ */
+IOMemoryDescriptor *
 IOMemoryDescriptor::withAddress(void *      address,
-    IOByteCount   length,
-    IODirection direction)
-{
-	return IOMemoryDescriptor::
-	       withAddressRange((IOVirtualAddress) address, length, direction | kIOMemoryAutoPrepare, kernel_task);
-}
-
-#ifndef __LP64__
-OSSharedPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withAddress(IOVirtualAddress address,
-    IOByteCount  length,
-    IODirection  direction,
-    task_t       task)
-{
-	OSSharedPtr<IOGeneralMemoryDescriptor> that = OSMakeShared<IOGeneralMemoryDescriptor>();
-	if (that) {
-		if (that->initWithAddress(address, length, direction, task)) {
-			return os::move(that);
-		}
-	}
-	return nullptr;
-}
-#endif /* !__LP64__ */
-
-OSSharedPtr<IOMemoryDescriptor>
+                                IOByteCount   length,
+                                IODirection direction)
+{
+    return IOMemoryDescriptor::
+        withAddress((vm_address_t) address, length, direction, kernel_task);
+}
+
+IOMemoryDescriptor *
+IOMemoryDescriptor::withAddress(vm_address_t address,
+                                IOByteCount  length,
+                                IODirection  direction,
+                                task_t       task)
+{
+    IOGeneralMemoryDescriptor * that = new IOGeneralMemoryDescriptor;
+    if (that)
+    {
+	if (that->initWithAddress(address, length, direction, task))
+	    return that;
+
+        that->release();
+    }
+    return 0;
+}
+
+IOMemoryDescriptor *
 IOMemoryDescriptor::withPhysicalAddress(
-	IOPhysicalAddress       address,
-	IOByteCount             length,
-	IODirection             direction )
-{
-	return IOMemoryDescriptor::withAddressRange(address, length, direction, TASK_NULL);
-}
-
-#ifndef __LP64__
-OSSharedPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withRanges( IOVirtualRange * ranges,
-    UInt32           withCount,
-    IODirection      direction,
-    task_t           task,
-    bool             asReference)
-{
-	OSSharedPtr<IOGeneralMemoryDescriptor> that = OSMakeShared<IOGeneralMemoryDescriptor>();
-	if (that) {
-		if (that->initWithRanges(ranges, withCount, direction, task, asReference)) {
-			return os::move(that);
-		}
-	}
-	return nullptr;
-}
-#endif /* !__LP64__ */
-
-OSSharedPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withAddressRange(mach_vm_address_t address,
-    mach_vm_size_t length,
-    IOOptionBits   options,
-    task_t         task)
-{
-	IOAddressRange range = { address, length };
-	return IOMemoryDescriptor::withAddressRanges(&range, 1, options, task);
-}
-
-OSSharedPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withAddressRanges(IOAddressRange *   ranges,
-    UInt32           rangeCount,
-    IOOptionBits     options,
-    task_t           task)
-{
-	OSSharedPtr<IOGeneralMemoryDescriptor> that = OSMakeShared<IOGeneralMemoryDescriptor>();
-	if (that) {
-		if (task) {
-			options |= kIOMemoryTypeVirtual64;
-		} else {
-			options |= kIOMemoryTypePhysical64;
-		}
-
-		if (that->initWithOptions(ranges, rangeCount, 0, task, options, /* mapper */ NULL)) {
-			return os::move(that);
-		}
-	}
-
-	return nullptr;
-}
-
-struct IOMemoryDescriptorWithVNodeInit {
-	ipc_port_t entry;
-	uint64_t   offset;
-	uint64_t   size;
-};
-
-OSPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withVNode(
-	struct vnode    *vnode,
-	uint64_t         offset,
-	uint64_t         size,
-	IOOptionBits     options)
-{
-	OSSharedPtr<IOMemoryDescriptor> self;
-	if (kIOMemoryTypeMask & options) {
-		return NULL;
-	}
-	ipc_port_t entry = vnode_memoryentry(vnode, offset, &size);
-	if (NULL == entry) {
-		return NULL;
-	}
-
-	IOMemoryDescriptorWithVNodeInit init = {
-		.entry = entry,
-		.offset = offset,
-		.size   = size };
-	self = IOMemoryDescriptor::withOptions(&init,
-	    1, 0, TASK_NULL, kIOMemoryTypeVnode | options, NULL);
-
-	if (NULL == self) {
-		mach_memory_entry_port_release(entry);
-	}
-
-	return self;
-}
+				IOPhysicalAddress	address,
+				IOByteCount		length,
+				IODirection      	direction )
+{
+    IOGeneralMemoryDescriptor *self = new IOGeneralMemoryDescriptor;
+    if (self
+    && !self->initWithPhysicalAddress(address, length, direction)) {
+        self->release();
+        return 0;
+    }
+
+    return self;
+}
+
+IOMemoryDescriptor *
+IOMemoryDescriptor::withRanges(	IOVirtualRange * ranges,
+				UInt32           withCount,
+				IODirection      direction,
+				task_t           task,
+				bool             asReference)
+{
+    IOGeneralMemoryDescriptor * that = new IOGeneralMemoryDescriptor;
+    if (that)
+    {
+	if (that->initWithRanges(ranges, withCount, direction, task, asReference))
+	    return that;
+
+        that->release();
+    }
+    return 0;
+}
+
 
 /*
- * withOptions:
+ * withRanges:
  *
  * Create a new IOMemoryDescriptor. The buffer is made up of several
  * virtual address ranges, from a given task.
  *
  * Passing the ranges as a reference will avoid an extra allocation.
  */
-OSSharedPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withOptions(void *          buffers,
-    UInt32          count,
-    UInt32          offset,
-    task_t          task,
-    IOOptionBits    opts,
-    IOMapper *      mapper)
-{
-	OSSharedPtr<IOGeneralMemoryDescriptor> self = OSMakeShared<IOGeneralMemoryDescriptor>();
-
-	if (self
-	    && !self->initWithOptions(buffers, count, offset, task, opts, mapper)) {
-		return nullptr;
+IOMemoryDescriptor *
+IOMemoryDescriptor::withOptions(void *		buffers,
+                                UInt32		count,
+                                UInt32		offset,
+                                task_t		task,
+                                IOOptionBits	opts,
+                                IOMapper *	mapper)
+{
+    IOGeneralMemoryDescriptor *self = new IOGeneralMemoryDescriptor;
+
+    if (self
+    && !self->initWithOptions(buffers, count, offset, task, opts, mapper))
+    {
+        self->release();
+        return 0;
+    }
+
+    return self;
+}
+
+// Can't leave abstract but this should never be used directly,
+bool IOMemoryDescriptor::initWithOptions(void *		buffers,
+                                         UInt32		count,
+                                         UInt32		offset,
+                                         task_t		task,
+                                         IOOptionBits	options,
+                                         IOMapper *	mapper)
+{
+    // @@@ gvdl: Should I panic?
+    panic("IOMD::initWithOptions called\n");
+    return 0;
+}
+
+IOMemoryDescriptor *
+IOMemoryDescriptor::withPhysicalRanges(	IOPhysicalRange * ranges,
+                                        UInt32          withCount,
+                                        IODirection     direction,
+                                        bool            asReference)
+{
+    IOGeneralMemoryDescriptor * that = new IOGeneralMemoryDescriptor;
+    if (that)
+    {
+	if (that->initWithPhysicalRanges(ranges, withCount, direction, asReference))
+	    return that;
+
+        that->release();
+    }
+    return 0;
+}
+
+IOMemoryDescriptor *
+IOMemoryDescriptor::withSubRange(IOMemoryDescriptor *	of,
+				IOByteCount		offset,
+				IOByteCount		length,
+				IODirection		direction)
+{
+    IOSubMemoryDescriptor *self = new IOSubMemoryDescriptor;
+
+    if (self && !self->initSubRange(of, offset, length, direction)) {
+        self->release();
+	self = 0;
+    }
+    return self;
+}
+
+IOMemoryDescriptor * IOMemoryDescriptor::
+    withPersistentMemoryDescriptor(IOMemoryDescriptor *originalMD)
+{
+    IOGeneralMemoryDescriptor *origGenMD = 
+	OSDynamicCast(IOGeneralMemoryDescriptor, originalMD);
+
+    if (origGenMD)
+	return IOGeneralMemoryDescriptor::
+	    withPersistentMemoryDescriptor(origGenMD);
+    else
+	return 0;
+}
+
+IOMemoryDescriptor * IOGeneralMemoryDescriptor::
+    withPersistentMemoryDescriptor(IOGeneralMemoryDescriptor *originalMD)
+{
+    ipc_port_t sharedMem = (ipc_port_t) originalMD->createNamedEntry();
+
+    if (!sharedMem)
+	return 0;
+   
+    if (sharedMem == originalMD->_memEntry) {
+	originalMD->retain();		    // Add a new reference to ourselves
+	ipc_port_release_send(sharedMem);   // Remove extra send right
+	return originalMD;
+    }
+
+    IOGeneralMemoryDescriptor * self = new IOGeneralMemoryDescriptor;
+    typePersMDData initData = { originalMD, sharedMem };
+
+    if (self
+    && !self->initWithOptions(&initData, 1, 0, 0, kIOMemoryTypePersistentMD, 0)) {
+        self->release();
+	self = 0;
+    }
+    return self;
+}
+
+void *IOGeneralMemoryDescriptor::createNamedEntry()
+{
+    kern_return_t error;
+    ipc_port_t sharedMem;
+
+    IOOptionBits type = _flags & kIOMemoryTypeMask;
+
+    user_addr_t range0Addr;
+    IOByteCount range0Len;
+    getAddrLenForInd(range0Addr, range0Len, type, _ranges, 0);
+    range0Addr = trunc_page_64(range0Addr);
+
+    vm_size_t size = ptoa_32(_pages);
+    vm_address_t kernelPage = (vm_address_t) range0Addr;
+
+    vm_map_t theMap = ((_task == kernel_task)
+			&& (kIOMemoryBufferPageable & _flags)) 
+		    ? IOPageableMapForAddress(kernelPage)
+		    : get_task_map(_task);
+
+    memory_object_size_t  actualSize = size;
+    vm_prot_t prot = VM_PROT_READ | VM_PROT_WRITE;
+    if (_memEntry)
+	prot |= MAP_MEM_NAMED_REUSE;
+
+    error = mach_make_memory_entry_64(theMap,
+	    &actualSize, range0Addr, prot, &sharedMem, (ipc_port_t) _memEntry);
+
+    if (KERN_SUCCESS == error) {
+	if (actualSize == size) {
+	    return sharedMem;
+	} else {
+#if IOASSERT
+	    IOLog("IOGMD::mach_make_memory_entry_64 (%08llx) size (%08lx:%08x)\n",
+			(UInt64)range0Addr, (UInt32)actualSize, size);
+#endif    
+	    ipc_port_release_send( sharedMem );
 	}
-
-	return os::move(self);
-}
-
-bool
-IOMemoryDescriptor::initWithOptions(void *         buffers,
-    UInt32         count,
-    UInt32         offset,
-    task_t         task,
-    IOOptionBits   options,
-    IOMapper *     mapper)
-{
-	return false;
-}
-
-#ifndef __LP64__
-OSSharedPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withPhysicalRanges( IOPhysicalRange * ranges,
-    UInt32          withCount,
-    IODirection     direction,
-    bool            asReference)
-{
-	OSSharedPtr<IOGeneralMemoryDescriptor> that = OSMakeShared<IOGeneralMemoryDescriptor>();
-	if (that) {
-		if (that->initWithPhysicalRanges(ranges, withCount, direction, asReference)) {
-			return os::move(that);
-		}
-	}
-	return nullptr;
-}
-
-OSSharedPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withSubRange(IOMemoryDescriptor *   of,
-    IOByteCount             offset,
-    IOByteCount             length,
-    IODirection             direction)
-{
-	return IOSubMemoryDescriptor::withSubRange(of, offset, length, direction);
-}
-#endif /* !__LP64__ */
-
-OSSharedPtr<IOMemoryDescriptor>
-IOMemoryDescriptor::withPersistentMemoryDescriptor(IOMemoryDescriptor *originalMD)
-{
-	IOGeneralMemoryDescriptor *origGenMD =
-	    OSDynamicCast(IOGeneralMemoryDescriptor, originalMD);
-
-	if (origGenMD) {
-		return IOGeneralMemoryDescriptor::
-		       withPersistentMemoryDescriptor(origGenMD);
-	} else {
-		return nullptr;
-	}
-}
-
-OSSharedPtr<IOMemoryDescriptor>
-IOGeneralMemoryDescriptor::withPersistentMemoryDescriptor(IOGeneralMemoryDescriptor *originalMD)
-{
-	IOMemoryReference * memRef;
-	OSSharedPtr<IOGeneralMemoryDescriptor> self;
-
-	if (kIOReturnSuccess != originalMD->memoryReferenceCreate(kIOMemoryReferenceReuse, &memRef)) {
-		return nullptr;
-	}
-
-	if (memRef == originalMD->_memRef) {
-		self.reset(originalMD, OSRetain);
-		originalMD->memoryReferenceRelease(memRef);
-		return os::move(self);
-	}
-
-	self = OSMakeShared<IOGeneralMemoryDescriptor>();
-	IOMDPersistentInitData initData = { originalMD, memRef };
-
-	if (self
-	    && !self->initWithOptions(&initData, 1, 0, NULL, kIOMemoryTypePersistentMD, NULL)) {
-		return nullptr;
-	}
-	return os::move(self);
-}
-
-#ifndef __LP64__
+    }
+
+    return MACH_PORT_NULL;
+}
+
+/*
+ * initWithAddress:
+ *
+ * Initialize an IOMemoryDescriptor. The buffer is a virtual address
+ * relative to the specified task.  If no task is supplied, the kernel
+ * task is implied.
+ *
+ * An IOMemoryDescriptor can be re-used by calling initWithAddress or
+ * initWithRanges again on an existing instance -- note this behavior
+ * is not commonly supported in other I/O Kit classes, although it is
+ * supported here.
+ */
 bool
 IOGeneralMemoryDescriptor::initWithAddress(void *      address,
-    IOByteCount   withLength,
-    IODirection withDirection)
-{
-	_singleRange.v.address = (vm_offset_t) address;
-	_singleRange.v.length  = withLength;
-
-	return initWithRanges(&_singleRange.v, 1, withDirection, kernel_task, true);
+                                    IOByteCount   withLength,
+                                    IODirection withDirection)
+{
+    _singleRange.v.address = (vm_address_t) address;
+    _singleRange.v.length  = withLength;
+
+    return initWithRanges(&_singleRange.v, 1, withDirection, kernel_task, true);
 }
 
 bool
-IOGeneralMemoryDescriptor::initWithAddress(IOVirtualAddress address,
-    IOByteCount    withLength,
-    IODirection  withDirection,
-    task_t       withTask)
-{
-	_singleRange.v.address = address;
-	_singleRange.v.length  = withLength;
-
-	return initWithRanges(&_singleRange.v, 1, withDirection, withTask, true);
+IOGeneralMemoryDescriptor::initWithAddress(vm_address_t address,
+                                    IOByteCount    withLength,
+                                    IODirection  withDirection,
+                                    task_t       withTask)
+{
+    _singleRange.v.address = address;
+    _singleRange.v.length  = withLength;
+
+    return initWithRanges(&_singleRange.v, 1, withDirection, withTask, true);
 }
 
 bool
 IOGeneralMemoryDescriptor::initWithPhysicalAddress(
-	IOPhysicalAddress      address,
-	IOByteCount            withLength,
-	IODirection            withDirection )
-{
-	_singleRange.p.address = address;
-	_singleRange.p.length  = withLength;
-
-	return initWithPhysicalRanges( &_singleRange.p, 1, withDirection, true);
+				 IOPhysicalAddress	address,
+				 IOByteCount		withLength,
+				 IODirection      	withDirection )
+{
+    _singleRange.p.address = address;
+    _singleRange.p.length  = withLength;
+
+    return initWithPhysicalRanges( &_singleRange.p, 1, withDirection, true);
 }
 
 bool
 IOGeneralMemoryDescriptor::initWithPhysicalRanges(
-	IOPhysicalRange * ranges,
-	UInt32            count,
-	IODirection       direction,
-	bool              reference)
-{
-	IOOptionBits mdOpts = direction | kIOMemoryTypePhysical;
-
-	if (reference) {
-		mdOpts |= kIOMemoryAsReference;
-	}
-
-	return initWithOptions(ranges, count, 0, NULL, mdOpts, /* mapper */ NULL);
+                                IOPhysicalRange * ranges,
+                                UInt32            count,
+                                IODirection       direction,
+                                bool              reference)
+{
+    IOOptionBits mdOpts = direction | kIOMemoryTypePhysical;
+
+    if (reference)
+        mdOpts |= kIOMemoryAsReference;
+
+    return initWithOptions(ranges, count, 0, 0, mdOpts, /* mapper */ 0);
 }
 
 bool
 IOGeneralMemoryDescriptor::initWithRanges(
-	IOVirtualRange * ranges,
-	UInt32           count,
-	IODirection      direction,
-	task_t           task,
-	bool             reference)
-{
-	IOOptionBits mdOpts = direction;
-
-	if (reference) {
-		mdOpts |= kIOMemoryAsReference;
-	}
-
-	if (task) {
-		mdOpts |= kIOMemoryTypeVirtual;
-
-		// Auto-prepare if this is a kernel memory descriptor as very few
-		// clients bother to prepare() kernel memory.
-		// But it was not enforced so what are you going to do?
-		if (task == kernel_task) {
-			mdOpts |= kIOMemoryAutoPrepare;
-		}
-	} else {
-		mdOpts |= kIOMemoryTypePhysical;
-	}
-
-	return initWithOptions(ranges, count, 0, task, mdOpts, /* mapper */ NULL);
-}
-#endif /* !__LP64__ */
+                                   IOVirtualRange * ranges,
+                                   UInt32           count,
+                                   IODirection      direction,
+                                   task_t           task,
+                                   bool             reference)
+{
+    IOOptionBits mdOpts = direction;
+
+    if (reference)
+        mdOpts |= kIOMemoryAsReference;
+
+    if (task) {
+        mdOpts |= kIOMemoryTypeVirtual;
+
+	// Auto-prepare if this is a kernel memory descriptor as very few
+	// clients bother to prepare() kernel memory.
+	// But it was not  enforced so what are you going to do?
+        if (task == kernel_task)
+            mdOpts |= kIOMemoryAutoPrepare;
+    }
+    else
+        mdOpts |= kIOMemoryTypePhysical;
+    
+    return initWithOptions(ranges, count, 0, task, mdOpts, /* mapper */ 0);
+}
 
 /*
  * initWithOptions:
@@ -2070,406 +633,231 @@
  */
 
 bool
-IOGeneralMemoryDescriptor::initWithOptions(void *       buffers,
-    UInt32       count,
-    UInt32       offset,
-    task_t       task,
-    IOOptionBits options,
-    IOMapper *   mapper)
-{
-	IOOptionBits type = options & kIOMemoryTypeMask;
-
-#ifndef __LP64__
-	if (task
-	    && (kIOMemoryTypeVirtual == type)
-	    && vm_map_is_64bit(get_task_map(task))
-	    && ((IOVirtualRange *) buffers)->address) {
-		OSReportWithBacktrace("IOMemoryDescriptor: attempt to create 32b virtual in 64b task, use ::withAddressRange()");
-		return false;
+IOGeneralMemoryDescriptor::initWithOptions(void *	buffers,
+                                           UInt32	count,
+                                           UInt32	offset,
+                                           task_t	task,
+                                           IOOptionBits	options,
+                                           IOMapper *	mapper)
+{
+    IOOptionBits type = options & kIOMemoryTypeMask;
+
+    // Grab the original MD's configuation data to initialse the
+    // arguments to this function.
+    if (kIOMemoryTypePersistentMD == type) {
+
+	typePersMDData *initData = (typePersMDData *) buffers;
+	const IOGeneralMemoryDescriptor *orig = initData->fMD;
+	ioGMDData *dataP = getDataP(orig->_memoryEntries);
+
+	// Only accept persistent memory descriptors with valid dataP data.
+	assert(orig->_rangesCount == 1);
+	if ( !(orig->_flags & kIOMemoryPersistent) || !dataP)
+	    return false;
+
+	_memEntry = initData->fMemEntry;	// Grab the new named entry
+	options = orig->_flags | kIOMemoryAsReference; 
+	_singleRange = orig->_singleRange;	// Initialise our range
+	buffers = &_singleRange;
+	count = 1;
+
+	// Now grab the original task and whatever mapper was previously used
+	task = orig->_task;
+	mapper = dataP->fMapper;
+
+	// We are ready to go through the original initialisation now
+    }
+
+    switch (type) {
+    case kIOMemoryTypeUIO:
+    case kIOMemoryTypeVirtual:
+        assert(task);
+        if (!task)
+            return false;
+        else
+            break;
+
+    case kIOMemoryTypePhysical:		// Neither Physical nor UPL should have a task
+	mapper = kIOMapperNone;
+
+    case kIOMemoryTypeUPL:
+        assert(!task);
+        break;
+    default:
+        return false;	/* bad argument */
+    }
+
+    assert(buffers);
+    assert(count);
+
+    /*
+     * We can check the _initialized  instance variable before having ever set
+     * it to an initial value because I/O Kit guarantees that all our instance
+     * variables are zeroed on an object's allocation.
+     */
+
+    if (_initialized) {
+        /*
+         * An existing memory descriptor is being retargeted to point to
+         * somewhere else.  Clean up our present state.
+         */
+
+        while (_wireCount)
+            complete();
+        if (_kernPtrAligned)
+            unmapFromKernel();
+        if (_ranges.v && _rangesIsAllocated)
+            IODelete(_ranges.v, IOVirtualRange, _rangesCount);
+	if (_memEntry)
+	    { ipc_port_release_send((ipc_port_t) _memEntry); _memEntry = 0; }
+    }
+    else {
+        if (!super::init())
+            return false;
+        _initialized = true;
+    }
+
+    // Grab the appropriate mapper
+    if (mapper == kIOMapperNone)
+        mapper = 0;	// No Mapper
+    else if (!mapper) {
+        IOMapper::checkForSystemMapper();
+        gIOSystemMapper = mapper = IOMapper::gSystem;
+    }
+
+    // Remove the dynamic internal use flags from the initial setting
+    options 		  &= ~(kIOMemoryPreparedReadOnly);
+    _flags		   = options;
+    _task                  = task;
+
+    // DEPRECATED variable initialisation
+    _direction             = (IODirection) (_flags & kIOMemoryDirectionMask);
+    _position              = 0;
+    _kernPtrAligned        = 0;
+    _cachedPhysicalAddress = 0;
+    _cachedVirtualAddress  = 0;
+
+    if (kIOMemoryTypeUPL == type) {
+
+        ioGMDData *dataP;
+        unsigned int dataSize = computeDataSize(/* pages */ 0, /* upls */ 1);
+
+        if (!_memoryEntries) {
+            _memoryEntries = OSData::withCapacity(dataSize);
+            if (!_memoryEntries)
+                return false;
+        }
+        else if (!_memoryEntries->initWithCapacity(dataSize))
+            return false;
+
+        _memoryEntries->appendBytes(0, sizeof(ioGMDData));
+        dataP = getDataP(_memoryEntries);
+        dataP->fMapper = mapper;
+        dataP->fPageCnt = 0;
+
+        _wireCount++;	// UPLs start out life wired
+
+        _length    = count;
+        _pages    += atop_32(offset + count + PAGE_MASK) - atop_32(offset);
+
+        ioPLBlock iopl;
+        upl_page_info_t *pageList = UPL_GET_INTERNAL_PAGE_LIST((upl_t) buffers);
+
+        iopl.fIOPL = (upl_t) buffers;
+        // Set the flag kIOPLOnDevice convieniently equal to 1
+        iopl.fFlags  = pageList->device | kIOPLExternUPL;
+        iopl.fIOMDOffset = 0;
+        if (!pageList->device) {
+            // Pre-compute the offset into the UPL's page list
+            pageList = &pageList[atop_32(offset)];
+            offset &= PAGE_MASK;
+            if (mapper) {
+                iopl.fMappedBase = mapper->iovmAlloc(_pages);
+                mapper->iovmInsert(iopl.fMappedBase, 0, pageList, _pages);
+            }
+	    else
+		iopl.fMappedBase = 0;
+        }
+	else
+	    iopl.fMappedBase = 0;
+        iopl.fPageInfo = (vm_address_t) pageList;
+        iopl.fPageOffset = offset;
+
+        _memoryEntries->appendBytes(&iopl, sizeof(iopl));
+    }
+    else {
+	// kIOMemoryTypeVirtual | kIOMemoryTypeUIO | kIOMemoryTypePhysical
+	
+	// Initialize the memory descriptor
+	if (options & kIOMemoryAsReference) {
+	    _rangesIsAllocated = false;
+
+	    // Hack assignment to get the buffer arg into _ranges.
+	    // I'd prefer to do _ranges = (Ranges) buffers, but that doesn't
+	    // work, C++ sigh.
+	    // This also initialises the uio & physical ranges.
+	    _ranges.v = (IOVirtualRange *) buffers;
 	}
-#endif /* !__LP64__ */
-
-	// Grab the original MD's configuation data to initialse the
-	// arguments to this function.
-	if (kIOMemoryTypePersistentMD == type) {
-		IOMDPersistentInitData *initData = (typeof(initData))buffers;
-		const IOGeneralMemoryDescriptor *orig = initData->fMD;
-		ioGMDData *dataP = getDataP(orig->_memoryEntries);
-
-		// Only accept persistent memory descriptors with valid dataP data.
-		assert(orig->_rangesCount == 1);
-		if (!(orig->_flags & kIOMemoryPersistent) || !dataP) {
-			return false;
-		}
-
-		_memRef = initData->fMemRef; // Grab the new named entry
-		options = orig->_flags & ~kIOMemoryAsReference;
-		type = options & kIOMemoryTypeMask;
-		buffers = orig->_ranges.v;
-		count = orig->_rangesCount;
-
-		// Now grab the original task and whatever mapper was previously used
-		task = orig->_task;
-		mapper = dataP->fMapper;
-
-		// We are ready to go through the original initialisation now
-	}
-
-	switch (type) {
-	case kIOMemoryTypeUIO:
-	case kIOMemoryTypeVirtual:
-#ifndef __LP64__
-	case kIOMemoryTypeVirtual64:
-#endif /* !__LP64__ */
-		assert(task);
-		if (!task) {
-			return false;
-		}
-		break;
-
-	case kIOMemoryTypePhysical:     // Neither Physical nor UPL should have a task
-#ifndef __LP64__
-	case kIOMemoryTypePhysical64:
-#endif /* !__LP64__ */
-	case kIOMemoryTypeUPL:
-		assert(!task);
-		break;
-
-	case kIOMemoryTypeVnode:
-		if (task) {
-			return false; /* bad argument */
-		}
-		if (_initialized
-		    || (options & kIOMemoryAsReference)) {
-			return false; /* bad argument */
-		}
-		if (task) {
-			return false; /* bad argument */
-		}
-		break;
-
-	default:
-		return false; /* bad argument */
-	}
-
-	assert(buffers);
-	assert(count);
-
-	/*
-	 * We can check the _initialized  instance variable before having ever set
-	 * it to an initial value because I/O Kit guarantees that all our instance
-	 * variables are zeroed on an object's allocation.
-	 */
-
-	if (_initialized) {
-		/*
-		 * An existing memory descriptor is being retargeted to point to
-		 * somewhere else.  Clean up our present state.
-		 */
-		IOOptionBits type = _flags & kIOMemoryTypeMask;
-		if ((kIOMemoryTypePhysical != type) && (kIOMemoryTypePhysical64 != type)) {
-			while (_wireCount) {
-				complete();
-			}
-		}
-		if (_ranges.v && !(kIOMemoryAsReference & _flags)) {
-			if (kIOMemoryTypeUIO == type) {
-				uio_free((uio_t) _ranges.v);
-			}
-#ifndef __LP64__
-			else if ((kIOMemoryTypeVirtual64 == type) || (kIOMemoryTypePhysical64 == type)) {
-				IODelete(_ranges.v64, IOAddressRange, _rangesCount);
-			}
-#endif /* !__LP64__ */
-			else {
-				IODelete(_ranges.v, IOVirtualRange, _rangesCount);
-			}
-		}
-
-		options |= (kIOMemoryRedirected & _flags);
-		if (!(kIOMemoryRedirected & options)) {
-			if (_memRef) {
-				memoryReferenceRelease(_memRef);
-				_memRef = NULL;
-			}
-			if (_mappings) {
-				_mappings->flushCollection();
-			}
-		}
-	} else {
-		if (!super::init()) {
-			return false;
-		}
-		_initialized = true;
-	}
-
-	// Grab the appropriate mapper
-	if (kIOMemoryHostOrRemote & options) {
-		options |= kIOMemoryMapperNone;
-	}
-	if (kIOMemoryMapperNone & options) {
-		mapper = NULL; // No Mapper
-	} else if (mapper == kIOMapperSystem) {
-		IOMapper::checkForSystemMapper();
-		gIOSystemMapper = mapper = IOMapper::gSystem;
-	}
-
-	// Remove the dynamic internal use flags from the initial setting
-	options               &= ~(kIOMemoryPreparedReadOnly);
-	_flags                 = options;
-	_task                  = task;
-
-#ifndef __LP64__
-	_direction             = (IODirection) (_flags & kIOMemoryDirectionMask);
-#endif /* !__LP64__ */
-
-	_dmaReferences = 0;
-	__iomd_reservedA = 0;
-	__iomd_reservedB = 0;
-	_highestPage = 0;
-
-	if (kIOMemoryThreadSafe & options) {
-		if (!_prepareLock) {
-			_prepareLock = IOLockAlloc();
-		}
-	} else if (_prepareLock) {
-		IOLockFree(_prepareLock);
-		_prepareLock = NULL;
-	}
-
-	if (kIOMemoryTypeUPL == type) {
-		ioGMDData *dataP;
-		unsigned int dataSize = computeDataSize(/* pages */ 0, /* upls */ 1);
-
-		if (!initMemoryEntries(dataSize, mapper)) {
-			return false;
-		}
-		dataP = getDataP(_memoryEntries);
-		dataP->fPageCnt = 0;
-		switch (kIOMemoryDirectionMask & options) {
-		case kIODirectionOut:
-			dataP->fDMAAccess = kIODMAMapReadAccess;
-			break;
-		case kIODirectionIn:
-			dataP->fDMAAccess = kIODMAMapWriteAccess;
-			break;
-		case kIODirectionNone:
-		case kIODirectionOutIn:
-		default:
-			panic("bad dir for upl 0x%x", (int) options);
-			break;
-		}
-		//       _wireCount++;	// UPLs start out life wired
-
-		_length    = count;
-		_pages    += atop_32(offset + count + PAGE_MASK) - atop_32(offset);
-
-		ioPLBlock iopl;
-		iopl.fIOPL = (upl_t) buffers;
-		upl_set_referenced(iopl.fIOPL, true);
-		upl_page_info_t *pageList = UPL_GET_INTERNAL_PAGE_LIST(iopl.fIOPL);
-
-		if (upl_get_size(iopl.fIOPL) < (count + offset)) {
-			panic("short external upl");
-		}
-
-		_highestPage = upl_get_highest_page(iopl.fIOPL);
-		DEBUG4K_IOKIT("offset 0x%x task %p options 0x%x -> _highestPage 0x%x\n", (uint32_t)offset, task, (uint32_t)options, _highestPage);
-
-		// Set the flag kIOPLOnDevice convieniently equal to 1
-		iopl.fFlags  = pageList->device | kIOPLExternUPL;
-		if (!pageList->device) {
-			// Pre-compute the offset into the UPL's page list
-			pageList = &pageList[atop_32(offset)];
-			offset &= PAGE_MASK;
-		}
-		iopl.fIOMDOffset = 0;
-		iopl.fMappedPage = 0;
-		iopl.fPageInfo = (vm_address_t) pageList;
-		iopl.fPageOffset = offset;
-		_memoryEntries->appendBytes(&iopl, sizeof(iopl));
-	} else {
-		// kIOMemoryTypeVirtual  | kIOMemoryTypeVirtual64 | kIOMemoryTypeUIO
-		// kIOMemoryTypePhysical | kIOMemoryTypePhysical64 | kIOMemoryTypeVnode
-
-		// Initialize the memory descriptor
-		if (options & kIOMemoryAsReference) {
-#ifndef __LP64__
-			_rangesIsAllocated = false;
-#endif /* !__LP64__ */
-
-			// Hack assignment to get the buffer arg into _ranges.
-			// I'd prefer to do _ranges = (Ranges) buffers, but that doesn't
-			// work, C++ sigh.
-			// This also initialises the uio & physical ranges.
-			_ranges.v = (IOVirtualRange *) buffers;
-		} else {
-#ifndef __LP64__
-			_rangesIsAllocated = true;
-#endif /* !__LP64__ */
-			switch (type) {
-			case kIOMemoryTypeUIO:
-				_ranges.v = (IOVirtualRange *) uio_duplicate((uio_t) buffers);
-				break;
-
-#ifndef __LP64__
-			case kIOMemoryTypeVirtual64:
-			case kIOMemoryTypePhysical64:
-				if (count == 1
-#ifndef __arm__
-				    && (((IOAddressRange *) buffers)->address + ((IOAddressRange *) buffers)->length) <= 0x100000000ULL
-#endif
-				    ) {
-					if (type == kIOMemoryTypeVirtual64) {
-						type = kIOMemoryTypeVirtual;
-					} else {
-						type = kIOMemoryTypePhysical;
-					}
-					_flags = (_flags & ~kIOMemoryTypeMask) | type | kIOMemoryAsReference;
-					_rangesIsAllocated = false;
-					_ranges.v = &_singleRange.v;
-					_singleRange.v.address = ((IOAddressRange *) buffers)->address;
-					_singleRange.v.length  = ((IOAddressRange *) buffers)->length;
-					break;
-				}
-				_ranges.v64 = IONew(IOAddressRange, count);
-				if (!_ranges.v64) {
-					return false;
-				}
-				bcopy(buffers, _ranges.v, count * sizeof(IOAddressRange));
-				break;
-#endif /* !__LP64__ */
-			case kIOMemoryTypeVirtual:
-			case kIOMemoryTypePhysical:
-				if (count == 1) {
-					_flags |= kIOMemoryAsReference;
-#ifndef __LP64__
-					_rangesIsAllocated = false;
-#endif /* !__LP64__ */
-					_ranges.v = &_singleRange.v;
-				} else {
-					_ranges.v = IONew(IOVirtualRange, count);
-					if (!_ranges.v) {
-						return false;
-					}
-				}
-				bcopy(buffers, _ranges.v, count * sizeof(IOVirtualRange));
-				break;
-
-			case kIOMemoryTypeVnode:
-				_flags |= kIOMemoryAsReference | kIOMemoryBufferPageable;
-				_task = kernel_task;
-#ifndef __LP64__
-				_rangesIsAllocated = false;
-#endif /* !__LP64__ */
-
-				const IOMemoryDescriptorWithVNodeInit * init = (typeof(init))buffers;
-				IOReturn
-				    err = memoryReferenceCreate(0, init->entry, init->offset, init->size, &_memRef);
-				if (kIOReturnSuccess != err) {
-					return false;
-				}
-				_ranges.v = &_singleRange.v;
-				_singleRange.v.address = 0;
-				_singleRange.v.length  = init->size;
-			}
-		}
-		_rangesCount = count;
-
-		// Find starting address within the vector of ranges
-		Ranges vec = _ranges;
-		mach_vm_size_t totalLength = 0;
-		unsigned int ind, pages = 0;
-		for (ind = 0; ind < count; ind++) {
-			mach_vm_address_t addr;
-			mach_vm_address_t endAddr;
-			mach_vm_size_t    len;
-
-			// addr & len are returned by this function
-			getAddrLenForInd(addr, len, type, vec, ind, _task);
-			if (_task) {
-				mach_vm_size_t phys_size;
-				kern_return_t kret;
-				kret = vm_map_range_physical_size(get_task_map(_task), addr, len, &phys_size);
-				if (KERN_SUCCESS != kret) {
-					break;
-				}
-				if (os_add_overflow(pages, atop_64(phys_size), &pages)) {
-					break;
-				}
-			} else {
-				if (os_add3_overflow(addr, len, PAGE_MASK, &endAddr)) {
-					break;
-				}
-				if (!(kIOMemoryRemote & options) && (atop_64(endAddr) > UINT_MAX)) {
-					break;
-				}
-				if (os_add_overflow(pages, (atop_64(endAddr) - atop_64(addr)), &pages)) {
-					break;
-				}
-			}
-			if (os_add_overflow(totalLength, len, &totalLength)) {
-				break;
-			}
-			if ((kIOMemoryTypePhysical == type) || (kIOMemoryTypePhysical64 == type)) {
-				uint64_t highPage = atop_64(addr + len - 1);
-				if ((highPage > _highestPage) && (highPage <= UINT_MAX)) {
-					_highestPage = (ppnum_t) highPage;
-					DEBUG4K_IOKIT("offset 0x%x task %p options 0x%x -> _highestPage 0x%x\n", (uint32_t)offset, task, (uint32_t)options, _highestPage);
-				}
-			}
-		}
-		if ((ind < count)
-		    || (totalLength != ((IOByteCount) totalLength))) {
-			return false;                                   /* overflow */
-		}
-		_length      = totalLength;
-		_pages       = pages;
-
-		// Auto-prepare memory at creation time.
-		// Implied completion when descriptor is free-ed
-
-		if ((kIOMemoryTypePhysical == type) || (kIOMemoryTypePhysical64 == type)) {
-			_wireCount++; // Physical MDs are, by definition, wired
-		} else { /* kIOMemoryTypeVirtual | kIOMemoryTypeVirtual64 | kIOMemoryTypeUIO | kIOMemoryTypeVNode */
-			ioGMDData *dataP;
-			unsigned dataSize;
-
-			if (_pages > atop_64(max_mem)) {
-				return false;
-			}
-
-			dataSize = computeDataSize(_pages, /* upls */ count * 2);
-			if (!initMemoryEntries(dataSize, mapper)) {
-				return false;
-			}
-			dataP = getDataP(_memoryEntries);
-			dataP->fPageCnt = _pages;
-
-			if (((_task != kernel_task) || (kIOMemoryBufferPageable & _flags))
-			    && (VM_KERN_MEMORY_NONE == _kernelTag)) {
-				_kernelTag = IOMemoryTag(kernel_map);
-				if (_kernelTag == gIOSurfaceTag) {
-					_userTag = VM_MEMORY_IOSURFACE;
-				}
-			}
-
-			if ((kIOMemoryPersistent & _flags) && !_memRef) {
-				IOReturn
-				    err = memoryReferenceCreate(0, &_memRef);
-				if (kIOReturnSuccess != err) {
-					return false;
-				}
-			}
-
-			if ((_flags & kIOMemoryAutoPrepare)
-			    && prepare() != kIOReturnSuccess) {
-				return false;
-			}
-		}
-	}
-
-	return true;
+	else {
+	    assert(kIOMemoryTypeUIO != type);
+
+	    _rangesIsAllocated = true;
+	    _ranges.v = IONew(IOVirtualRange, count);
+	    if (!_ranges.v)
+                return false;
+	    bcopy(buffers, _ranges.v, count * sizeof(IOVirtualRange));
+	} 
+
+	// Find starting address within the vector of ranges
+	Ranges vec = _ranges;
+	UInt32 length = 0;
+	UInt32 pages = 0;
+	for (unsigned ind = 0; ind < count;  ind++) {
+	    user_addr_t addr;
+	    UInt32 len;
+
+	    // addr & len are returned by this function
+	    getAddrLenForInd(addr, len, type, vec, ind);
+	    pages += (atop_64(addr + len + PAGE_MASK) - atop_64(addr));
+	    len += length;
+	    assert(len > length);	// Check for 32 bit wrap around
+	    length = len;
+	} 
+	_length      = length;
+	_pages       = pages;
+	_rangesCount = count;
+
+        // Auto-prepare memory at creation time.
+        // Implied completion when descriptor is free-ed
+        if (kIOMemoryTypePhysical == type)
+            _wireCount++;	// Physical MDs are, by definition, wired
+        else { /* kIOMemoryTypeVirtual | kIOMemoryTypeUIO */
+            ioGMDData *dataP;
+            unsigned dataSize = computeDataSize(_pages, /* upls */ count * 2);
+
+            if (!_memoryEntries) {
+                _memoryEntries = OSData::withCapacity(dataSize);
+                if (!_memoryEntries)
+		    return false;
+            }
+            else if (!_memoryEntries->initWithCapacity(dataSize))
+                return false;
+    
+            _memoryEntries->appendBytes(0, sizeof(ioGMDData));
+            dataP = getDataP(_memoryEntries);
+            dataP->fMapper = mapper;
+            dataP->fPageCnt = _pages;
+
+	    if ( (kIOMemoryPersistent & _flags) && !_memEntry)
+		_memEntry = createNamedEntry();
+
+            if ((_flags & kIOMemoryAutoPrepare)
+             && prepare() != kIOReturnSuccess)
+                return false;
+        }
+    }
+
+    return true;
 }
 
 /*
@@ -2477,98 +865,52 @@
  *
  * Free resources.
  */
-void
-IOGeneralMemoryDescriptor::free()
-{
-	IOOptionBits type = _flags & kIOMemoryTypeMask;
-
-	if (reserved && reserved->dp.memory) {
-		LOCK;
-		reserved->dp.memory = NULL;
-		UNLOCK;
-	}
-	if ((kIOMemoryTypePhysical == type) || (kIOMemoryTypePhysical64 == type)) {
-		ioGMDData * dataP;
-		if (_memoryEntries && (dataP = getDataP(_memoryEntries)) && dataP->fMappedBaseValid) {
-			dmaUnmap(dataP->fMapper, NULL, 0, dataP->fMappedBase, dataP->fMappedLength);
-			dataP->fMappedBaseValid = dataP->fMappedBase = 0;
-		}
-	} else {
-		while (_wireCount) {
-			complete();
-		}
-	}
-
-	if (_memoryEntries) {
-		_memoryEntries.reset();
-	}
-
-	if (_ranges.v && !(kIOMemoryAsReference & _flags)) {
-		if (kIOMemoryTypeUIO == type) {
-			uio_free((uio_t) _ranges.v);
-		}
-#ifndef __LP64__
-		else if ((kIOMemoryTypeVirtual64 == type) || (kIOMemoryTypePhysical64 == type)) {
-			IODelete(_ranges.v64, IOAddressRange, _rangesCount);
-		}
-#endif /* !__LP64__ */
-		else {
-			IODelete(_ranges.v, IOVirtualRange, _rangesCount);
-		}
-
-		_ranges.v = NULL;
-	}
-
-	if (reserved) {
-		cleanKernelReserved(reserved);
-		if (reserved->dp.devicePager) {
-			// memEntry holds a ref on the device pager which owns reserved
-			// (IOMemoryDescriptorReserved) so no reserved access after this point
-			device_pager_deallocate((memory_object_t) reserved->dp.devicePager );
-		} else {
-			IOFreeType(reserved, IOMemoryDescriptorReserved);
-		}
-		reserved = NULL;
-	}
-
-	if (_memRef) {
-		memoryReferenceRelease(_memRef);
-	}
-	if (_prepareLock) {
-		IOLockFree(_prepareLock);
-	}
-
-	super::free();
-}
-
-#ifndef __LP64__
-void
-IOGeneralMemoryDescriptor::unmapFromKernel()
-{
-	panic("IOGMD::unmapFromKernel deprecated");
-}
-
-void
-IOGeneralMemoryDescriptor::mapIntoKernel(unsigned rangeIndex)
-{
-	panic("IOGMD::mapIntoKernel deprecated");
-}
-#endif /* !__LP64__ */
+void IOGeneralMemoryDescriptor::free()
+{
+    LOCK;
+    if( reserved)
+	reserved->memory = 0;
+    UNLOCK;
+
+    while (_wireCount)
+        complete();
+    if (_memoryEntries)
+        _memoryEntries->release();
+
+    if (_kernPtrAligned)
+        unmapFromKernel();
+    if (_ranges.v && _rangesIsAllocated)
+        IODelete(_ranges.v, IOVirtualRange, _rangesCount);
+
+    if (reserved && reserved->devicePager)
+	device_pager_deallocate( (memory_object_t) reserved->devicePager );
+
+    // memEntry holds a ref on the device pager which owns reserved
+    // (ExpansionData) so no reserved access after this point
+    if (_memEntry)
+        ipc_port_release_send( (ipc_port_t) _memEntry );
+
+    super::free();
+}
+
+/* DEPRECATED */ void IOGeneralMemoryDescriptor::unmapFromKernel()
+/* DEPRECATED */ {
+                    panic("IOGMD::unmapFromKernel deprecated");
+/* DEPRECATED */ }
+/* DEPRECATED */ 
+/* DEPRECATED */ void IOGeneralMemoryDescriptor::mapIntoKernel(unsigned rangeIndex)
+/* DEPRECATED */ {
+                    panic("IOGMD::mapIntoKernel deprecated");
+/* DEPRECATED */ }
 
 /*
  * getDirection:
  *
  * Get the direction of the transfer.
  */
-IODirection
-IOMemoryDescriptor::getDirection() const
-{
-#ifndef __LP64__
-	if (_direction) {
-		return _direction;
-	}
-#endif /* !__LP64__ */
-	return (IODirection) (_flags & kIOMemoryDirectionMask);
+IODirection IOMemoryDescriptor::getDirection() const
+{
+    return _direction;
 }
 
 /*
@@ -2576,2440 +918,725 @@
  *
  * Get the length of the transfer (over all ranges).
  */
-IOByteCount
-IOMemoryDescriptor::getLength() const
-{
-	return _length;
-}
-
-void
-IOMemoryDescriptor::setTag( IOOptionBits tag )
-{
-	_tag = tag;
-}
-
-IOOptionBits
-IOMemoryDescriptor::getTag( void )
-{
-	return _tag;
-}
-
-uint64_t
-IOMemoryDescriptor::getFlags(void)
-{
-	return _flags;
-}
-
-OSObject *
-IOMemoryDescriptor::copyContext(const OSSymbol * key) const
-{
-	if (reserved && reserved->contextObjects) {
-		OSObject * context = reserved->contextObjects->getObject(key);
-		if (context) {
-			context->retain();
-		}
-		return context;
-	} else {
-		return NULL;
-	}
-}
-
-OSObject *
-IOMemoryDescriptor::copyContext(const char * key) const
-{
-	OSSharedPtr<const OSSymbol> sym = OSSymbol::withCString(key);
-	return copyContext(sym.get());
-}
-
-OSObject *
-IOMemoryDescriptor::copySharingContext(const char * key) const
-{
-	OSObject * context = NULL;
-	OSObject * obj = copyContext(kIOMemoryDescriptorSharingContextKey);
-	OSDictionary * dict = OSDynamicCast(OSDictionary, obj);
-	if (dict) {
-		context = dict->getObject(key);
-		if (context) {
-			context->retain();
-		}
-	}
-	OSSafeReleaseNULL(obj);
-	return context;
-}
-
-void
-IOMemoryDescriptor::setContext(const OSSymbol * key, OSObject * obj)
-{
-	if (this->reserved == NULL && obj == NULL) {
-		// No existing object, and no object to set
-		return;
-	}
-
-	IOMemoryDescriptorReserved * reserved = getKernelReserved();
-	if (reserved) {
-		if (NULL == reserved->contextObjects) {
-			reserved->contextObjects = OSDictionary::withCapacity(2);
-		}
-		if (obj) {
-			reserved->contextObjects->setObject(key, obj);
-		} else {
-			reserved->contextObjects->removeObject(key);
-		}
-	}
-}
-
-void
-IOMemoryDescriptor::setContext(const char * key, OSObject * obj)
-{
-	OSSharedPtr<const OSSymbol> sym = OSSymbol::withCString(key);
-	setContext(sym.get(), obj);
-}
-
-OSObject *
-IOMemoryDescriptor::copyContext(void) const
-{
-	return copyContext((const OSSymbol *) kOSBooleanFalse);
-}
-enum {
-	kIOMemoryDescriptorInternalFlagsSharing = 0x0001,
-};
-
-void
-IOMemoryDescriptor::setSharingContext(const char * key, OSObject * obj)
-{
-	OSSharedPtr<const OSSymbol> sym = OSSymbol::withCString(key);
-	OSSharedPtr<OSDictionary> dict = OSDictionary::withCapacity(1);
-
-	dict->setObject(sym.get(), obj);
-	setContext(kIOMemoryDescriptorSharingContextKey, dict.get());
-	OSBitOrAtomic16(kIOMemoryDescriptorInternalFlagsSharing, &_internalIOMDFlags);
-}
-
-bool
-IOMemoryDescriptor::hasSharingContext(void)
-{
-	return 0 != (kIOMemoryDescriptorInternalFlagsSharing & _internalIOMDFlags);
-}
-
-void
-IOMemoryDescriptor::setContext(OSObject * obj)
-{
-	setContext((const OSSymbol *) kOSBooleanFalse, obj);
-}
-
-#ifndef __LP64__
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+IOByteCount IOMemoryDescriptor::getLength() const
+{
+    return _length;
+}
+
+void IOMemoryDescriptor::setTag( IOOptionBits tag )
+{
+    _tag = tag;    
+}
+
+IOOptionBits IOMemoryDescriptor::getTag( void )
+{
+    return( _tag);
+}
 
 // @@@ gvdl: who is using this API?  Seems like a wierd thing to implement.
-IOPhysicalAddress
-IOMemoryDescriptor::getSourceSegment( IOByteCount   offset, IOByteCount * length )
-{
-	addr64_t physAddr = 0;
-
-	if (prepare() == kIOReturnSuccess) {
-		physAddr = getPhysicalSegment64( offset, length );
-		complete();
-	}
-
-	return (IOPhysicalAddress) physAddr; // truncated but only page offset is used
-}
-
-#pragma clang diagnostic pop
-
-#endif /* !__LP64__ */
-
-#if HAS_MTE
-/* Ideally this would be a method on IOMD that's overridden by IOGMD, but there's
- * ABI considerations with extending the vtable so just make it a free function for now.
- */
-static void
-handleCopyAbortedTCF(void)
-{
-	/*
-	 * Only calls passing through an IOGMD will have a faultable provider, so we check
-	 * for one here, as we might have recovered from a tag check fault through e.g.
-	 * an IOSubMD that cannot provide one.
-	 */
-	task_t task_providing_faultable_buffer = current_thread_get_iomd_faultable_access_buffer_provider();
-	if (task_providing_faultable_buffer) {
-		/*
-		 * Register an AST over the victim task so that a proper MTE exception
-		 * will be generated when it gets scheduled. The fault handler already
-		 * recorded the necessary data that the exception-synthesizing code
-		 * will require to create the exception.
-		 */
-		task_set_ast_synthesize_async_fault_mach_exception(task_providing_faultable_buffer);
-	}
-}
-#endif /* HAS_MTE */
-
-IOByteCount
-IOMemoryDescriptor::readBytes
-(IOByteCount offset, void *bytes, IOByteCount length)
-{
-	addr64_t dstAddr = CAST_DOWN(addr64_t, bytes);
-	IOByteCount endoffset;
-	IOByteCount remaining;
-
-	// Check that this entire I/O is within the available range
-	if ((offset > _length)
-	    || os_add_overflow(length, offset, &endoffset)
-	    || (endoffset > _length)) {
-		assertf(false, "readBytes exceeds length (0x%lx, 0x%lx) > 0x%lx", (long) offset, (long) length, (long) _length);
-		return 0;
-	}
-	if (offset >= _length) {
-		return 0;
-	}
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		return 0;
-	}
-
-	if (kIOMemoryThreadSafe & _flags) {
-		LOCK;
-	}
-
-	remaining = length = IOMin(length, _length - offset);
-	while (remaining) { // (process another target segment?)
-		addr64_t        srcAddr64;
-		IOByteCount     srcLen;
-		int             options = cppvPsrc | cppvNoRefSrc | cppvFsnk | cppvKmap;
-
-		IOOptionBits getPhysSegmentOptions = kIOMemoryMapperNone;
-		srcAddr64 = getPhysicalSegment(offset, &srcLen, getPhysSegmentOptions);
-		if (!srcAddr64) {
-			break;
-		}
-
-		// Clip segment length to remaining
-		if (srcLen > remaining) {
-			srcLen = remaining;
-		}
-
-		if (srcLen > (UINT_MAX - PAGE_SIZE + 1)) {
-			srcLen = (UINT_MAX - PAGE_SIZE + 1);
-		}
-
-#if HAS_MTE
-		if (pmap_is_tagged_page((ppnum_t)atop(srcAddr64))) {
-			if (current_thread_get_iomd_faultable_access_buffer_provider() != NULL) {
-				/*
-				 * We're going to wind up accessing the memory via peeking into the
-				 * physical aperture. Our physical aperture access will naturally be
-				 * canonically tagged, which will mismatch the correct tag. This option
-				 * tells bcopy_phys to actually fixup via LDG the tag. We won't catch
-				 * UaFs with this, but any OOB will fault therefore...
-				 */
-				options |= cppvFixupPhysmapTag;
-
-				/*
-				 * ...this flag sets up machinery such that fault on this access will be
-				 * recoverable (i.e. this thread will continue execution). We can do that
-				 * only when coming through an IOGMD and having a faultable task to blame.
-				 */
-				options |= cppvDenoteAccessMayFault;
-
-				/*
-				 * And if we do fault during the access, it also means we don't have
-				 * recourse to read the memory contents.
-				 * Unfortunately, consumers of this API expect it to always work, so
-				 * in an attempt to minimize risk we'll zero the buffer upfront,
-				 * so if we failed to read it'll look as though we just read zeroes.
-				 */
-				memset((void*)dstAddr, 0, srcLen);
-			} else {
-				/*
-				 * We don't have a task to blame, resort to the unsafe TCO copy.
-				 * We could just return EFAULT here, but that would require callers to
-				 * actively check for it, which unfortunately may not be the case as
-				 * these operations never failed before.
-				 *
-				 * Defer a proper support to buffered creation of IOMDs.
-				 */
-				options |= cppvDisableTagCheck;
-			}
-		}
-#endif /* HAS_MTE */
-
-		kern_return_t copy_ret = copypv(srcAddr64, dstAddr, (unsigned int) srcLen, options);
-#if HAS_MTE
-		/*
-		 * copypv recovery handler will only fire in case of a tag check fault. Let's handle
-		 * the special case here.
-		 */
-		if (copy_ret == KERN_ABORTED) {
-			handleCopyAbortedTCF();
-		}
-#else /* HAS_MTE */
-#pragma unused(copy_ret)
-#endif /* HAS_MTE */
-
-		dstAddr   += srcLen;
-		offset    += srcLen;
-		remaining -= srcLen;
-	}
-
-	if (kIOMemoryThreadSafe & _flags) {
-		UNLOCK;
-	}
-
-	assert(!remaining);
-
-	return length - remaining;
-}
-
-IOByteCount
-IOMemoryDescriptor::writeBytes
-(IOByteCount inoffset, const void *bytes, IOByteCount length)
-{
-	addr64_t srcAddr = CAST_DOWN(addr64_t, bytes);
-	IOByteCount remaining;
-	IOByteCount endoffset;
-	IOByteCount offset = inoffset;
-
-	assert( !(kIOMemoryPreparedReadOnly & _flags));
-
-	// Check that this entire I/O is within the available range
-	if ((offset > _length)
-	    || os_add_overflow(length, offset, &endoffset)
-	    || (endoffset > _length)) {
-		assertf(false, "writeBytes exceeds length (0x%lx, 0x%lx) > 0x%lx", (long) inoffset, (long) length, (long) _length);
-		return 0;
-	}
-	if (kIOMemoryPreparedReadOnly & _flags) {
-		return 0;
-	}
-	if (offset >= _length) {
-		return 0;
-	}
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		return 0;
-	}
-
-	if (kIOMemoryThreadSafe & _flags) {
-		LOCK;
-	}
-
-	remaining = length = IOMin(length, _length - offset);
-	while (remaining) { // (process another target segment?)
-		addr64_t    dstAddr64;
-		IOByteCount dstLen;
-		int         options = cppvPsnk | cppvFsnk | cppvNoRefSrc | cppvNoModSnk | cppvKmap;
-
-		IOOptionBits getPhysSegmentOptions = kIOMemoryMapperNone;
-		dstAddr64 = getPhysicalSegment(offset, &dstLen, getPhysSegmentOptions);
-		if (!dstAddr64) {
-			break;
-		}
-
-		// Clip segment length to remaining
-		if (dstLen > remaining) {
-			dstLen = remaining;
-		}
-
-		if (dstLen > (UINT_MAX - PAGE_SIZE + 1)) {
-			dstLen = (UINT_MAX - PAGE_SIZE + 1);
-		}
-
-#if HAS_MTE
-		if (pmap_is_tagged_page((ppnum_t)atop(dstAddr64))) {
-			/* Same drill as readBytes(), please check the comment there for details. */
-			if (current_thread_get_iomd_faultable_access_buffer_provider() != NULL) {
-				options |= cppvFixupPhysmapTag;
-				options |= cppvDenoteAccessMayFault;
-			} else {
-				options |= cppvDisableTagCheck;
-			}
-		}
-#endif /* HAS_MTE */
-
-		if (!srcAddr) {
-			bzero_phys(dstAddr64, (unsigned int) dstLen);
-		} else {
-			kern_return_t copy_ret = copypv(srcAddr, (addr64_t) dstAddr64, (unsigned int) dstLen, options);
-#if HAS_MTE
-			/*
-			 * copypv recovery handler will only fire in case of a tag check fault. Let's handle
-			 * the special case here.
-			 */
-			if (copy_ret == KERN_ABORTED) {
-				handleCopyAbortedTCF();
-			}
-#else /* HAS_MTE */
-#pragma unused(copy_ret)
-#endif /* HAS_MTE */
-			srcAddr   += dstLen;
-		}
-		offset    += dstLen;
-		remaining -= dstLen;
-	}
-
-	if (kIOMemoryThreadSafe & _flags) {
-		UNLOCK;
-	}
-
-	assert(!remaining);
-
-#if defined(__x86_64__)
-	// copypv does not cppvFsnk on intel
-#else
-	if (!srcAddr) {
-		performOperation(kIOMemoryIncoherentIOFlush, inoffset, length);
-	}
-#endif
-
-	return length - remaining;
-}
-
-#ifndef __LP64__
-void
-IOGeneralMemoryDescriptor::setPosition(IOByteCount position)
-{
-	panic("IOGMD::setPosition deprecated");
-}
-#endif /* !__LP64__ */
-
-static volatile SInt64 gIOMDPreparationID __attribute__((aligned(8))) = (1ULL << 32);
-static volatile SInt64 gIOMDDescriptorID __attribute__((aligned(8))) = (kIODescriptorIDInvalid + 1ULL);
-
-uint64_t
-IOGeneralMemoryDescriptor::getPreparationID( void )
-{
-	ioGMDData *dataP;
-
-	if (!_wireCount) {
-		return kIOPreparationIDUnprepared;
-	}
-
-	if (((kIOMemoryTypeMask & _flags) == kIOMemoryTypePhysical)
-	    || ((kIOMemoryTypeMask & _flags) == kIOMemoryTypePhysical64)) {
-		IOMemoryDescriptor::setPreparationID();
-		return IOMemoryDescriptor::getPreparationID();
-	}
-
-	if (!_memoryEntries || !(dataP = getDataP(_memoryEntries))) {
-		return kIOPreparationIDUnprepared;
-	}
-
-	if (kIOPreparationIDUnprepared == dataP->fPreparationID) {
-		SInt64 newID = OSIncrementAtomic64(&gIOMDPreparationID);
-		OSCompareAndSwap64(kIOPreparationIDUnprepared, newID, &dataP->fPreparationID);
-	}
-	return dataP->fPreparationID;
-}
-
-void
-IOMemoryDescriptor::cleanKernelReserved( IOMemoryDescriptorReserved * reserved )
-{
-	if (reserved->creator) {
-		task_deallocate(reserved->creator);
-		reserved->creator = NULL;
-	}
-
-	reserved->contextObjects = NULL;
-}
-
-IOMemoryDescriptorReserved *
-IOMemoryDescriptor::getKernelReserved( void )
-{
-	if (!reserved) {
-		reserved = IOMallocType(IOMemoryDescriptorReserved);
-	}
-	return reserved;
-}
-
-void
-IOMemoryDescriptor::setPreparationID( void )
-{
-	if (getKernelReserved() && (kIOPreparationIDUnprepared == reserved->preparationID)) {
-		SInt64 newID = OSIncrementAtomic64(&gIOMDPreparationID);
-		OSCompareAndSwap64(kIOPreparationIDUnprepared, newID, &reserved->preparationID);
-	}
-}
-
-uint64_t
-IOMemoryDescriptor::getPreparationID( void )
-{
-	if (reserved) {
-		return reserved->preparationID;
-	} else {
-		return kIOPreparationIDUnsupported;
-	}
-}
-
-void
-IOMemoryDescriptor::setDescriptorID( void )
-{
-	if (getKernelReserved() && (kIODescriptorIDInvalid == reserved->descriptorID)) {
-		SInt64 newID = OSIncrementAtomic64(&gIOMDDescriptorID);
-		OSCompareAndSwap64(kIODescriptorIDInvalid, newID, &reserved->descriptorID);
-	}
-}
-
-uint64_t
-IOMemoryDescriptor::getDescriptorID( void )
-{
-	setDescriptorID();
-
-	if (reserved) {
-		return reserved->descriptorID;
-	} else {
-		return kIODescriptorIDInvalid;
-	}
-}
-
-IOReturn
-IOMemoryDescriptor::ktraceEmitPhysicalSegments( void )
-{
-	if (!kdebug_debugid_enabled(IODBG_IOMDPA(IOMDPA_MAPPED))) {
-		return kIOReturnSuccess;
-	}
-
-	assert(getPreparationID() >= kIOPreparationIDAlwaysPrepared);
-	if (getPreparationID() < kIOPreparationIDAlwaysPrepared) {
-		return kIOReturnBadArgument;
-	}
-
-	uint64_t descriptorID = getDescriptorID();
-	assert(descriptorID != kIODescriptorIDInvalid);
-	if (getDescriptorID() == kIODescriptorIDInvalid) {
-		return kIOReturnBadArgument;
-	}
-
-	IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_MAPPED), descriptorID, VM_KERNEL_ADDRHIDE(this), getLength());
-
-#if __LP64__
-	static const uint8_t num_segments_page = 8;
-#else
-	static const uint8_t num_segments_page = 4;
-#endif
-	static const uint8_t num_segments_long = 2;
-
-	IOPhysicalAddress segments_page[num_segments_page];
-	IOPhysicalRange   segments_long[num_segments_long];
-	memset(segments_page, UINT32_MAX, sizeof(segments_page));
-	memset(segments_long, 0, sizeof(segments_long));
-
-	uint8_t segment_page_idx = 0;
-	uint8_t segment_long_idx = 0;
-
-	IOPhysicalRange physical_segment;
-	for (IOByteCount offset = 0; offset < getLength(); offset += physical_segment.length) {
-		physical_segment.address = getPhysicalSegment(offset, &physical_segment.length);
-
-		if (physical_segment.length == 0) {
-			break;
-		}
-
-		/**
-		 * Most IOMemoryDescriptors are made up of many individual physically discontiguous pages.  To optimize for trace
-		 * buffer memory, pack segment events according to the following.
-		 *
-		 * Mappings must be emitted in ascending order starting from offset 0.  Mappings can be associated with the previous
-		 * IOMDPA_MAPPED event emitted on by the current thread_id.
-		 *
-		 * IOMDPA_SEGMENTS_PAGE        = up to 8 virtually contiguous page aligned mappings of PAGE_SIZE length
-		 * - (ppn_0 << 32 | ppn_1), ..., (ppn_6 << 32 | ppn_7)
-		 * - unmapped pages will have a ppn of MAX_INT_32
-		 * IOMDPA_SEGMENTS_LONG	= up to 2 virtually contiguous mappings of variable length
-		 * - address_0, length_0, address_0, length_1
-		 * - unmapped pages will have an address of 0
-		 *
-		 * During each iteration do the following depending on the length of the mapping:
-		 * 1. add the current segment to the appropriate queue of pending segments
-		 * 1. check if we are operating on the same type of segment (PAGE/LONG) as the previous pass
-		 * 1a. if FALSE emit and reset all events in the previous queue
-		 * 2. check if we have filled up the current queue of pending events
-		 * 2a. if TRUE emit and reset all events in the pending queue
-		 * 3. after completing all iterations emit events in the current queue
-		 */
-
-		bool emit_page = false;
-		bool emit_long = false;
-		if ((physical_segment.address & PAGE_MASK) == 0 && physical_segment.length == PAGE_SIZE) {
-			segments_page[segment_page_idx] = physical_segment.address;
-			segment_page_idx++;
-
-			emit_long = segment_long_idx != 0;
-			emit_page = segment_page_idx == num_segments_page;
-
-			if (os_unlikely(emit_long)) {
-				IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_LONG),
-				    segments_long[0].address, segments_long[0].length,
-				    segments_long[1].address, segments_long[1].length);
-			}
-
-			if (os_unlikely(emit_page)) {
-#if __LP64__
-				IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_PAGE),
-				    ((uintptr_t) atop_64(segments_page[0]) << 32) | (ppnum_t) atop_64(segments_page[1]),
-				    ((uintptr_t) atop_64(segments_page[2]) << 32) | (ppnum_t) atop_64(segments_page[3]),
-				    ((uintptr_t) atop_64(segments_page[4]) << 32) | (ppnum_t) atop_64(segments_page[5]),
-				    ((uintptr_t) atop_64(segments_page[6]) << 32) | (ppnum_t) atop_64(segments_page[7]));
-#else
-				IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_PAGE),
-				    (ppnum_t) atop_32(segments_page[1]),
-				    (ppnum_t) atop_32(segments_page[2]),
-				    (ppnum_t) atop_32(segments_page[3]),
-				    (ppnum_t) atop_32(segments_page[4]));
-#endif
-			}
-		} else {
-			segments_long[segment_long_idx] = physical_segment;
-			segment_long_idx++;
-
-			emit_page = segment_page_idx != 0;
-			emit_long = segment_long_idx == num_segments_long;
-
-			if (os_unlikely(emit_page)) {
-#if __LP64__
-				IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_PAGE),
-				    ((uintptr_t) atop_64(segments_page[0]) << 32) | (ppnum_t) atop_64(segments_page[1]),
-				    ((uintptr_t) atop_64(segments_page[2]) << 32) | (ppnum_t) atop_64(segments_page[3]),
-				    ((uintptr_t) atop_64(segments_page[4]) << 32) | (ppnum_t) atop_64(segments_page[5]),
-				    ((uintptr_t) atop_64(segments_page[6]) << 32) | (ppnum_t) atop_64(segments_page[7]));
-#else
-				IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_PAGE),
-				    (ppnum_t) atop_32(segments_page[1]),
-				    (ppnum_t) atop_32(segments_page[2]),
-				    (ppnum_t) atop_32(segments_page[3]),
-				    (ppnum_t) atop_32(segments_page[4]));
-#endif
-			}
-
-			if (emit_long) {
-				IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_LONG),
-				    segments_long[0].address, segments_long[0].length,
-				    segments_long[1].address, segments_long[1].length);
-			}
-		}
-
-		if (os_unlikely(emit_page)) {
-			memset(segments_page, UINT32_MAX, sizeof(segments_page));
-			segment_page_idx = 0;
-		}
-
-		if (os_unlikely(emit_long)) {
-			memset(segments_long, 0, sizeof(segments_long));
-			segment_long_idx = 0;
-		}
-	}
-
-	if (segment_page_idx != 0) {
-		assert(segment_long_idx == 0);
-#if __LP64__
-		IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_PAGE),
-		    ((uintptr_t) atop_64(segments_page[0]) << 32) | (ppnum_t) atop_64(segments_page[1]),
-		    ((uintptr_t) atop_64(segments_page[2]) << 32) | (ppnum_t) atop_64(segments_page[3]),
-		    ((uintptr_t) atop_64(segments_page[4]) << 32) | (ppnum_t) atop_64(segments_page[5]),
-		    ((uintptr_t) atop_64(segments_page[6]) << 32) | (ppnum_t) atop_64(segments_page[7]));
-#else
-		IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_PAGE),
-		    (ppnum_t) atop_32(segments_page[1]),
-		    (ppnum_t) atop_32(segments_page[2]),
-		    (ppnum_t) atop_32(segments_page[3]),
-		    (ppnum_t) atop_32(segments_page[4]));
-#endif
-	} else if (segment_long_idx != 0) {
-		assert(segment_page_idx == 0);
-		IOTimeStampConstant(IODBG_IOMDPA(IOMDPA_SEGMENTS_LONG),
-		    segments_long[0].address, segments_long[0].length,
-		    segments_long[1].address, segments_long[1].length);
-	}
-
-	return kIOReturnSuccess;
-}
-
-void
-IOMemoryDescriptor::setVMTags(uint32_t kernelTag, uint32_t userTag)
-{
-	_kernelTag = (vm_tag_t) kernelTag;
-	_userTag   = (vm_tag_t) userTag;
-}
-
-uint32_t
-IOMemoryDescriptor::getVMTag(vm_map_t map)
-{
-	if (vm_kernel_map_is_kernel(map)) {
-		if (VM_KERN_MEMORY_NONE != _kernelTag) {
-			return (uint32_t) _kernelTag;
-		}
-	} else {
-		if (VM_KERN_MEMORY_NONE != _userTag) {
-			return (uint32_t) _userTag;
-		}
-	}
-	return IOMemoryTag(map);
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const
-{
-	IOReturn err = kIOReturnSuccess;
-	DMACommandOps params;
-	IOGeneralMemoryDescriptor * md = const_cast<IOGeneralMemoryDescriptor *>(this);
-	ioGMDData *dataP;
-
-	params = (op & ~kIOMDDMACommandOperationMask & op);
-	op &= kIOMDDMACommandOperationMask;
-
-	if (kIOMDDMAMap == op) {
-		if (dataSize < sizeof(IOMDDMAMapArgs)) {
-			return kIOReturnUnderrun;
-		}
-
-		IOMDDMAMapArgs * data = (IOMDDMAMapArgs *) vData;
-
-		if (!_memoryEntries
-		    && !md->initMemoryEntries(computeDataSize(0, 0), kIOMapperWaitSystem)) {
-			return kIOReturnNoMemory;
-		}
-
-		if (_memoryEntries && data->fMapper) {
-			bool remap, keepMap;
-			dataP = getDataP(_memoryEntries);
-
-			if (data->fMapSpec.numAddressBits < dataP->fDMAMapNumAddressBits) {
-				dataP->fDMAMapNumAddressBits = data->fMapSpec.numAddressBits;
-			}
-			if (data->fMapSpec.alignment > dataP->fDMAMapAlignment) {
-				dataP->fDMAMapAlignment      = data->fMapSpec.alignment;
-			}
-
-			keepMap = (data->fMapper == gIOSystemMapper);
-			keepMap &= ((data->fOffset == 0) && (data->fLength == _length));
-
-			if ((data->fMapper == gIOSystemMapper) && _prepareLock) {
-				IOLockLock(_prepareLock);
-			}
-
-			remap = (!keepMap);
-			remap |= (dataP->fDMAMapNumAddressBits < 64)
-			    && ((dataP->fMappedBase + _length) > (1ULL << dataP->fDMAMapNumAddressBits));
-			remap |= (dataP->fDMAMapAlignment > page_size);
-
-			if (remap || !dataP->fMappedBaseValid) {
-				err = md->dmaMap(data->fMapper, md, data->fCommand, &data->fMapSpec, data->fOffset, data->fLength, &data->fAlloc, &data->fAllocLength);
-				if (keepMap && (kIOReturnSuccess == err) && !dataP->fMappedBaseValid) {
-					dataP->fMappedBase      = data->fAlloc;
-					dataP->fMappedBaseValid = true;
-					dataP->fMappedLength    = data->fAllocLength;
-					data->fAllocLength      = 0;    // IOMD owns the alloc now
-				}
-			} else {
-				data->fAlloc = dataP->fMappedBase;
-				data->fAllocLength = 0;         // give out IOMD map
-				md->dmaMapRecord(data->fMapper, data->fCommand, dataP->fMappedLength);
-			}
-
-			if ((data->fMapper == gIOSystemMapper) && _prepareLock) {
-				IOLockUnlock(_prepareLock);
-			}
-		}
-		return err;
-	}
-	if (kIOMDDMAUnmap == op) {
-		if (dataSize < sizeof(IOMDDMAMapArgs)) {
-			return kIOReturnUnderrun;
-		}
-		IOMDDMAMapArgs * data = (IOMDDMAMapArgs *) vData;
-
-		if (_pages) {
-			err = md->dmaUnmap(data->fMapper, data->fCommand, data->fOffset, data->fAlloc, data->fAllocLength);
-		}
-
-		return kIOReturnSuccess;
-	}
-
-	if (kIOMDAddDMAMapSpec == op) {
-		if (dataSize < sizeof(IODMAMapSpecification)) {
-			return kIOReturnUnderrun;
-		}
-
-		IODMAMapSpecification * data = (IODMAMapSpecification *) vData;
-
-		if (!_memoryEntries
-		    && !md->initMemoryEntries(computeDataSize(0, 0), kIOMapperWaitSystem)) {
-			return kIOReturnNoMemory;
-		}
-
-		if (_memoryEntries) {
-			dataP = getDataP(_memoryEntries);
-			if (data->numAddressBits < dataP->fDMAMapNumAddressBits) {
-				dataP->fDMAMapNumAddressBits = data->numAddressBits;
-			}
-			if (data->alignment > dataP->fDMAMapAlignment) {
-				dataP->fDMAMapAlignment = data->alignment;
-			}
-		}
-		return kIOReturnSuccess;
-	}
-
-	if (kIOMDGetCharacteristics == op) {
-		if (dataSize < sizeof(IOMDDMACharacteristics)) {
-			return kIOReturnUnderrun;
-		}
-
-		IOMDDMACharacteristics *data = (IOMDDMACharacteristics *) vData;
-		data->fLength = _length;
-		data->fSGCount = _rangesCount;
-		data->fPages = _pages;
-		data->fDirection = getDirection();
-		if (!_wireCount) {
-			data->fIsPrepared = false;
-		} else {
-			data->fIsPrepared = true;
-			data->fHighestPage = _highestPage;
-			if (_memoryEntries) {
-				dataP = getDataP(_memoryEntries);
-				ioPLBlock *ioplList = getIOPLList(dataP);
-				UInt count = getNumIOPL(_memoryEntries, dataP);
-				if (count == 1) {
-					data->fPageAlign = (ioplList[0].fPageOffset & PAGE_MASK) | ~PAGE_MASK;
-				}
-			}
-		}
-
-		return kIOReturnSuccess;
-	} else if (kIOMDDMAActive == op) {
-		if (params) {
-			int16_t prior;
-			prior = OSAddAtomic16(1, &md->_dmaReferences);
-			if (!prior) {
-				md->_mapName = NULL;
-			}
-		} else {
-			if (md->_dmaReferences) {
-				OSAddAtomic16(-1, &md->_dmaReferences);
-			} else {
-				panic("_dmaReferences underflow");
-			}
-		}
-	} else if (kIOMDWalkSegments != op) {
-		return kIOReturnBadArgument;
-	}
-
-	// Get the next segment
-	struct InternalState {
-		IOMDDMAWalkSegmentArgs fIO;
-		mach_vm_size_t fOffset2Index;
-		mach_vm_size_t fNextOffset;
-		UInt fIndex;
-	} *isP;
-
-	// Find the next segment
-	if (dataSize < sizeof(*isP)) {
-		return kIOReturnUnderrun;
-	}
-
-	isP = (InternalState *) vData;
-	uint64_t offset = isP->fIO.fOffset;
-	uint8_t mapped = isP->fIO.fMapped;
-	uint64_t mappedBase;
-
-	if (mapped && (kIOMemoryRemote & _flags)) {
-		return kIOReturnNotAttached;
-	}
-
-	if (IOMapper::gSystem && mapped
-	    && (!(kIOMemoryHostOnly & _flags))
-	    && (!_memoryEntries || !getDataP(_memoryEntries)->fMappedBaseValid)) {
-//	&& (_memoryEntries && !getDataP(_memoryEntries)->fMappedBaseValid))
-		if (!_memoryEntries
-		    && !md->initMemoryEntries(computeDataSize(0, 0), kIOMapperWaitSystem)) {
-			return kIOReturnNoMemory;
-		}
-
-		dataP = getDataP(_memoryEntries);
-		if (dataP->fMapper) {
-			IODMAMapSpecification mapSpec;
-			bzero(&mapSpec, sizeof(mapSpec));
-			mapSpec.numAddressBits = dataP->fDMAMapNumAddressBits;
-			mapSpec.alignment = dataP->fDMAMapAlignment;
-			err = md->dmaMap(dataP->fMapper, md, NULL, &mapSpec, 0, _length, &dataP->fMappedBase, &dataP->fMappedLength);
-			if (kIOReturnSuccess != err) {
-				return err;
-			}
-			dataP->fMappedBaseValid = true;
-		}
-	}
-
-	if (mapped) {
-		if (IOMapper::gSystem
-		    && (!(kIOMemoryHostOnly & _flags))
-		    && _memoryEntries
-		    && (dataP = getDataP(_memoryEntries))
-		    && dataP->fMappedBaseValid) {
-			mappedBase = dataP->fMappedBase;
-		} else {
-			mapped = 0;
-		}
-	}
-
-	if (offset >= _length) {
-		return (offset == _length)? kIOReturnOverrun : kIOReturnInternalError;
-	}
-
-	// Validate the previous offset
-	UInt ind;
-	mach_vm_size_t off2Ind = isP->fOffset2Index;
-	if (!params
-	    && offset
-	    && (offset == isP->fNextOffset || off2Ind <= offset)) {
-		ind = isP->fIndex;
-	} else {
-		ind = off2Ind = 0; // Start from beginning
-	}
-	mach_vm_size_t length;
-	UInt64 address;
-
-	if ((_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical) {
-		// Physical address based memory descriptor
-		const IOPhysicalRange *physP = (IOPhysicalRange *) &_ranges.p[0];
-
-		// Find the range after the one that contains the offset
-		mach_vm_size_t len;
-		for (len = 0; off2Ind <= offset; ind++) {
-			len = physP[ind].length;
-			off2Ind += len;
-		}
-
-		// Calculate length within range and starting address
-		length   = off2Ind - offset;
-		address  = physP[ind - 1].address + len - length;
-
-		if (true && mapped) {
-			address = mappedBase + offset;
-		} else {
-			// see how far we can coalesce ranges
-			while (ind < _rangesCount && address + length == physP[ind].address) {
-				len = physP[ind].length;
-				length += len;
-				off2Ind += len;
-				ind++;
-			}
-		}
-
-		// correct contiguous check overshoot
-		ind--;
-		off2Ind -= len;
-	}
-#ifndef __LP64__
-	else if ((_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical64) {
-		// Physical address based memory descriptor
-		const IOAddressRange *physP = (IOAddressRange *) &_ranges.v64[0];
-
-		// Find the range after the one that contains the offset
-		mach_vm_size_t len;
-		for (len = 0; off2Ind <= offset; ind++) {
-			len = physP[ind].length;
-			off2Ind += len;
-		}
-
-		// Calculate length within range and starting address
-		length   = off2Ind - offset;
-		address  = physP[ind - 1].address + len - length;
-
-		if (true && mapped) {
-			address = mappedBase + offset;
-		} else {
-			// see how far we can coalesce ranges
-			while (ind < _rangesCount && address + length == physP[ind].address) {
-				len = physP[ind].length;
-				length += len;
-				off2Ind += len;
-				ind++;
-			}
-		}
-		// correct contiguous check overshoot
-		ind--;
-		off2Ind -= len;
-	}
-#endif /* !__LP64__ */
-	else {
-		do {
-			if (!_wireCount) {
-				panic("IOGMD: not wired for the IODMACommand");
-			}
-
-			assert(_memoryEntries);
-
-			dataP = getDataP(_memoryEntries);
-			const ioPLBlock *ioplList = getIOPLList(dataP);
-			UInt numIOPLs = getNumIOPL(_memoryEntries, dataP);
-			upl_page_info_t *pageList = getPageList(dataP);
-
-			assert(numIOPLs > 0);
-
-			// Scan through iopl info blocks looking for block containing offset
-			while (ind < numIOPLs && offset >= ioplList[ind].fIOMDOffset) {
-				ind++;
-			}
-
-			// Go back to actual range as search goes past it
-			ioPLBlock ioplInfo = ioplList[ind - 1];
-			off2Ind = ioplInfo.fIOMDOffset;
-
-			if (ind < numIOPLs) {
-				length = ioplList[ind].fIOMDOffset;
-			} else {
-				length = _length;
-			}
-			length -= offset;       // Remainder within iopl
-
-			// Subtract offset till this iopl in total list
-			offset -= off2Ind;
-
-			// If a mapped address is requested and this is a pre-mapped IOPL
-			// then just need to compute an offset relative to the mapped base.
-			if (mapped) {
-				offset += (ioplInfo.fPageOffset & PAGE_MASK);
-				address = trunc_page_64(mappedBase) + ptoa_64(ioplInfo.fMappedPage) + offset;
-				continue; // Done leave do/while(false) now
-			}
-
-			// The offset is rebased into the current iopl.
-			// Now add the iopl 1st page offset.
-			offset += ioplInfo.fPageOffset;
-
-			// For external UPLs the fPageInfo field points directly to
-			// the upl's upl_page_info_t array.
-			if (ioplInfo.fFlags & kIOPLExternUPL) {
-				pageList = (upl_page_info_t *) ioplInfo.fPageInfo;
-			} else {
-				pageList = &pageList[ioplInfo.fPageInfo];
-			}
-
-			// Check for direct device non-paged memory
-			if (ioplInfo.fFlags & kIOPLOnDevice) {
-				address = ptoa_64(pageList->phys_addr) + offset;
-				continue; // Done leave do/while(false) now
-			}
-
-			// Now we need compute the index into the pageList
-			UInt pageInd = atop_32(offset);
-			offset &= PAGE_MASK;
-
-			// Compute the starting address of this segment
-			IOPhysicalAddress pageAddr = pageList[pageInd].phys_addr;
-			if (!pageAddr) {
-				panic("!pageList phys_addr");
-			}
-
-			address = ptoa_64(pageAddr) + offset;
-
-			// length is currently set to the length of the remainider of the iopl.
-			// We need to check that the remainder of the iopl is contiguous.
-			// This is indicated by pageList[ind].phys_addr being sequential.
-			IOByteCount contigLength = PAGE_SIZE - offset;
-			while (contigLength < length
-			    && ++pageAddr == pageList[++pageInd].phys_addr) {
-				contigLength += PAGE_SIZE;
-			}
-
-			if (contigLength < length) {
-				length = contigLength;
-			}
-
-			assert(address);
-			assert(length);
-		} while (false);
-	}
-
-	// Update return values and state
-	isP->fIO.fIOVMAddr = address;
-	isP->fIO.fLength   = length;
-	isP->fIndex        = ind;
-	isP->fOffset2Index = off2Ind;
-	isP->fNextOffset   = isP->fIO.fOffset + length;
-
-	return kIOReturnSuccess;
-}
-
-addr64_t
-IOGeneralMemoryDescriptor::getPhysicalSegment(IOByteCount offset, IOByteCount *lengthOfSegment, IOOptionBits options)
-{
-	IOReturn          ret;
-	mach_vm_address_t address = 0;
-	mach_vm_size_t    length  = 0;
-	IOMapper *        mapper  = gIOSystemMapper;
-	IOOptionBits      type    = _flags & kIOMemoryTypeMask;
-
-	if (lengthOfSegment) {
-		*lengthOfSegment = 0;
-	}
-
-	if (offset >= _length) {
-		return 0;
-	}
-
-	// IOMemoryDescriptor::doMap() cannot use getPhysicalSegment() to obtain the page offset, since it must
-	// support the unwired memory case in IOGeneralMemoryDescriptor, and hibernate_write_image() cannot use
-	// map()->getVirtualAddress() to obtain the kernel pointer, since it must prevent the memory allocation
-	// due to IOMemoryMap, so _kIOMemorySourceSegment is a necessary evil until all of this gets cleaned up
-
-	if ((options & _kIOMemorySourceSegment) && (kIOMemoryTypeUPL != type)) {
-		unsigned rangesIndex = 0;
-		Ranges vec = _ranges;
-		mach_vm_address_t addr;
-
-		// Find starting address within the vector of ranges
-		for (;;) {
-			getAddrLenForInd(addr, length, type, vec, rangesIndex, _task);
-			if (offset < length) {
-				break;
-			}
-			offset -= length; // (make offset relative)
-			rangesIndex++;
-		}
-
-		// Now that we have the starting range,
-		// lets find the last contiguous range
-		addr   += offset;
-		length -= offset;
-
-		for (++rangesIndex; rangesIndex < _rangesCount; rangesIndex++) {
-			mach_vm_address_t newAddr;
-			mach_vm_size_t    newLen;
-
-			getAddrLenForInd(newAddr, newLen, type, vec, rangesIndex, _task);
-			if (addr + length != newAddr) {
-				break;
-			}
-			length += newLen;
-		}
-		if (addr) {
-			address = (IOPhysicalAddress) addr; // Truncate address to 32bit
-		}
-	} else {
-		IOMDDMAWalkSegmentState _state;
-		IOMDDMAWalkSegmentArgs * state = (IOMDDMAWalkSegmentArgs *) (void *)&_state;
-
-		state->fOffset = offset;
-		state->fLength = _length - offset;
-		state->fMapped = (0 == (options & kIOMemoryMapperNone)) && !(_flags & kIOMemoryHostOrRemote);
-
-		ret = dmaCommandOperation(kIOMDFirstSegment, _state, sizeof(_state));
-
-		if ((kIOReturnSuccess != ret) && (kIOReturnOverrun != ret)) {
-			DEBG("getPhysicalSegment dmaCommandOperation(%lx), %p, offset %qx, addr %qx, len %qx\n",
-			    ret, this, state->fOffset,
-			    state->fIOVMAddr, state->fLength);
-		}
-		if (kIOReturnSuccess == ret) {
-			address = state->fIOVMAddr;
-			length  = state->fLength;
-		}
-
-		// dmaCommandOperation() does not distinguish between "mapped" and "unmapped" physical memory, even
-		// with fMapped set correctly, so we must handle the transformation here until this gets cleaned up
-
-		if (mapper && ((kIOMemoryTypePhysical == type) || (kIOMemoryTypePhysical64 == type))) {
-			if ((options & kIOMemoryMapperNone) && !(_flags & kIOMemoryMapperNone)) {
-				addr64_t    origAddr = address;
-				IOByteCount origLen  = length;
-
-				address = mapper->mapToPhysicalAddress(origAddr);
-				length = page_size - (address & (page_size - 1));
-				while ((length < origLen)
-				    && ((address + length) == mapper->mapToPhysicalAddress(origAddr + length))) {
-					length += page_size;
-				}
-				if (length > origLen) {
-					length = origLen;
-				}
-			}
-		}
-	}
-
-	if (!address) {
-		length = 0;
-	}
-
-	if (lengthOfSegment) {
-		*lengthOfSegment = length;
-	}
-
-	return address;
-}
-
-IOByteCount
-IOGeneralMemoryDescriptor::readBytes
-(IOByteCount offset, void *bytes, IOByteCount length)
-{
-#if HAS_MTE
-	/* We might fault while accessing the wired memory if the underlying memory
-	 * is tagged and someone else has since changed the tag.
-	 * We need to set up context on the current thread so that we can keep track
-	 * of who caused us to fault within the fault handler.
-	 * Here, 'who caused us to fault' would be the other end of the true
-	 * share (i.e. the task which handed us the memory in the first place).
-	 * Ideally we'd only set up this context just surrounding the potentially
-	 * faulting access, but the access happens deeper within IOMD machinery
-	 * by which point we've lost this _task ivar. So, just hold onto it here.
-	 * (Note that it's possible for the culprit who changed the tag to be
-	 * another party holding a true share to the mapping, separate from the task
-	 * which handed us the memory that backs the IOMD, but we're not going to
-	 * worry too much about this case for now.)
-	 */
-	/* Note that we don't need any special handling for when _task is NULL. */
-	current_thread_enter_iomd_faultable_access_with_buffer_provider(_task);
-#endif /* HAS_MTE */
-	IOByteCount count = super::readBytes(offset, bytes, length);
-#if HAS_MTE
-	current_thread_exit_iomd_faultable_access();
-#endif /* HAS_MTE */
-	return count;
-}
-
-IOByteCount
-IOGeneralMemoryDescriptor::writeBytes
-(IOByteCount offset, const void* bytes, IOByteCount withLength)
-{
-#if HAS_MTE
-	/* We might fault while accessing the wired memory if the underlying memory
-	 * is tagged and someone else has since changed the tag.
-	 * We need to set up context on the current thread so that we can keep track
-	 * of who caused us to fault within the fault handler.
-	 * Here, 'who caused us to fault' would be the other end of the true
-	 * share (i.e. the task which handed us the memory in the first place).
-	 * Ideally we'd only set up this context just surrounding the potentially
-	 * faulting access, but the access happens deeper within IOMD machinery
-	 * by which point we've lost this _task ivar. So, just hold onto it here.
-	 * (Note that it's possible for the culprit who changed the tag to be
-	 * another party holding a true share to the mapping, separate from the task
-	 * which handed us the memory that backs the IOMD, but we're not going to
-	 * worry too much about this case for now.)
-	 */
-	/* Note that we don't need any special handling for when _task is NULL. */
-	current_thread_enter_iomd_faultable_access_with_buffer_provider(_task);
-#endif /* HAS_MTE */
-	IOByteCount count = super::writeBytes(offset, bytes, withLength);
-#if HAS_MTE
-	current_thread_exit_iomd_faultable_access();
-#endif /* HAS_MTE */
-	return count;
-}
-
-#ifndef __LP64__
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-
-addr64_t
-IOMemoryDescriptor::getPhysicalSegment(IOByteCount offset, IOByteCount *lengthOfSegment, IOOptionBits options)
-{
-	addr64_t address = 0;
-
-	if (options & _kIOMemorySourceSegment) {
-		address = getSourceSegment(offset, lengthOfSegment);
-	} else if (options & kIOMemoryMapperNone) {
-		address = getPhysicalSegment64(offset, lengthOfSegment);
-	} else {
-		address = getPhysicalSegment(offset, lengthOfSegment);
-	}
-
-	return address;
-}
-#pragma clang diagnostic pop
-
-addr64_t
-IOGeneralMemoryDescriptor::getPhysicalSegment64(IOByteCount offset, IOByteCount *lengthOfSegment)
-{
-	return getPhysicalSegment(offset, lengthOfSegment, kIOMemoryMapperNone);
-}
-
-IOPhysicalAddress
-IOGeneralMemoryDescriptor::getPhysicalSegment(IOByteCount offset, IOByteCount *lengthOfSegment)
-{
-	addr64_t    address = 0;
-	IOByteCount length  = 0;
-
-	address = getPhysicalSegment(offset, lengthOfSegment, 0);
-
-	if (lengthOfSegment) {
-		length = *lengthOfSegment;
-	}
-
-	if ((address + length) > 0x100000000ULL) {
-		panic("getPhysicalSegment() out of 32b range 0x%qx, len 0x%lx, class %s",
-		    address, (long) length, (getMetaClass())->getClassName());
-	}
-
-	return (IOPhysicalAddress) address;
-}
-
-addr64_t
-IOMemoryDescriptor::getPhysicalSegment64(IOByteCount offset, IOByteCount *lengthOfSegment)
-{
-	IOPhysicalAddress phys32;
-	IOByteCount       length;
-	addr64_t          phys64;
-	IOMapper *        mapper = NULL;
-
-	phys32 = getPhysicalSegment(offset, lengthOfSegment);
-	if (!phys32) {
-		return 0;
-	}
-
-	if (gIOSystemMapper) {
-		mapper = gIOSystemMapper;
-	}
-
-	if (mapper) {
-		IOByteCount origLen;
-
-		phys64 = mapper->mapToPhysicalAddress(phys32);
-		origLen = *lengthOfSegment;
-		length = page_size - (phys64 & (page_size - 1));
-		while ((length < origLen)
-		    && ((phys64 + length) == mapper->mapToPhysicalAddress(phys32 + length))) {
-			length += page_size;
-		}
-		if (length > origLen) {
-			length = origLen;
-		}
-
-		*lengthOfSegment = length;
-	} else {
-		phys64 = (addr64_t) phys32;
-	}
-
-	return phys64;
-}
-
-IOPhysicalAddress
-IOMemoryDescriptor::getPhysicalSegment(IOByteCount offset, IOByteCount *lengthOfSegment)
-{
-	return (IOPhysicalAddress) getPhysicalSegment(offset, lengthOfSegment, 0);
-}
-
-IOPhysicalAddress
-IOGeneralMemoryDescriptor::getSourceSegment(IOByteCount offset, IOByteCount *lengthOfSegment)
-{
-	return (IOPhysicalAddress) getPhysicalSegment(offset, lengthOfSegment, _kIOMemorySourceSegment);
-}
-
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-
-void *
-IOGeneralMemoryDescriptor::getVirtualSegment(IOByteCount offset,
-    IOByteCount * lengthOfSegment)
-{
-	if (_task == kernel_task) {
-		return (void *) getSourceSegment(offset, lengthOfSegment);
-	} else {
-		panic("IOGMD::getVirtualSegment deprecated");
-	}
-
-	return NULL;
-}
-#pragma clang diagnostic pop
-#endif /* !__LP64__ */
-
-IOReturn
-IOMemoryDescriptor::dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const
-{
-	IOMemoryDescriptor *md = const_cast<IOMemoryDescriptor *>(this);
-	DMACommandOps params;
-	IOReturn err;
-
-	params = (op & ~kIOMDDMACommandOperationMask & op);
-	op &= kIOMDDMACommandOperationMask;
-
-	if (kIOMDGetCharacteristics == op) {
-		if (dataSize < sizeof(IOMDDMACharacteristics)) {
-			return kIOReturnUnderrun;
-		}
-
-		IOMDDMACharacteristics *data = (IOMDDMACharacteristics *) vData;
-		data->fLength = getLength();
-		data->fSGCount = 0;
-		data->fDirection = getDirection();
-		data->fIsPrepared = true; // Assume prepared - fails safe
-	} else if (kIOMDWalkSegments == op) {
-		if (dataSize < sizeof(IOMDDMAWalkSegmentArgs)) {
-			return kIOReturnUnderrun;
-		}
-
-		IOMDDMAWalkSegmentArgs *data = (IOMDDMAWalkSegmentArgs *) vData;
-		IOByteCount offset  = (IOByteCount) data->fOffset;
-		IOPhysicalLength length, nextLength;
-		addr64_t         addr, nextAddr;
-
-		if (data->fMapped) {
-			panic("fMapped %p %s %qx", this, getMetaClass()->getClassName(), (uint64_t) getLength());
-		}
-		addr = md->getPhysicalSegment(offset, &length, kIOMemoryMapperNone);
-		offset += length;
-		while (offset < getLength()) {
-			nextAddr = md->getPhysicalSegment(offset, &nextLength, kIOMemoryMapperNone);
-			if ((addr + length) != nextAddr) {
-				break;
-			}
-			length += nextLength;
-			offset += nextLength;
-		}
-		data->fIOVMAddr = addr;
-		data->fLength   = length;
-	} else if (kIOMDAddDMAMapSpec == op) {
-		return kIOReturnUnsupported;
-	} else if (kIOMDDMAMap == op) {
-		if (dataSize < sizeof(IOMDDMAMapArgs)) {
-			return kIOReturnUnderrun;
-		}
-		IOMDDMAMapArgs * data = (IOMDDMAMapArgs *) vData;
-
-		err = md->dmaMap(data->fMapper, md, data->fCommand, &data->fMapSpec, data->fOffset, data->fLength, &data->fAlloc, &data->fAllocLength);
-
-		return err;
-	} else if (kIOMDDMAUnmap == op) {
-		if (dataSize < sizeof(IOMDDMAMapArgs)) {
-			return kIOReturnUnderrun;
-		}
-		IOMDDMAMapArgs * data = (IOMDDMAMapArgs *) vData;
-
-		err = md->dmaUnmap(data->fMapper, data->fCommand, data->fOffset, data->fAlloc, data->fAllocLength);
-
-		return kIOReturnSuccess;
-	} else {
-		return kIOReturnBadArgument;
-	}
-
-	return kIOReturnSuccess;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::setPurgeable( IOOptionBits newState,
-    IOOptionBits * oldState )
-{
-	IOReturn      err = kIOReturnSuccess;
-
-	vm_purgable_t control;
-	int           state;
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		return kIOReturnNotAttached;
-	}
-
-	if (_memRef) {
-		err = super::setPurgeable(newState, oldState);
-	} else {
-		if (kIOMemoryThreadSafe & _flags) {
-			LOCK;
-		}
-		do{
-			// Find the appropriate vm_map for the given task
-			vm_map_t curMap;
-			if (_task == kernel_task && (kIOMemoryBufferPageable & _flags)) {
-				err = kIOReturnNotReady;
-				break;
-			} else if (!_task) {
-				err = kIOReturnUnsupported;
-				break;
-			} else {
-				curMap = get_task_map(_task);
-				if (NULL == curMap) {
-					err = KERN_INVALID_ARGUMENT;
-					break;
-				}
-			}
-
-			// can only do one range
-			Ranges vec = _ranges;
-			IOOptionBits type = _flags & kIOMemoryTypeMask;
-			mach_vm_address_t addr;
-			mach_vm_size_t    len;
-			getAddrLenForInd(addr, len, type, vec, 0, _task);
-
-			err = purgeableControlBits(newState, &control, &state);
-			if (kIOReturnSuccess != err) {
-				break;
-			}
-			err = vm_map_purgable_control(curMap, addr, control, &state);
-			if (oldState) {
-				if (kIOReturnSuccess == err) {
-					err = purgeableStateBits(&state);
-					*oldState = state;
-				}
-			}
-		}while (false);
-		if (kIOMemoryThreadSafe & _flags) {
-			UNLOCK;
-		}
-	}
-
-	return err;
-}
-
-IOReturn
-IOMemoryDescriptor::setPurgeable( IOOptionBits newState,
-    IOOptionBits * oldState )
-{
-	IOReturn err = kIOReturnNotReady;
-
-	if (kIOMemoryThreadSafe & _flags) {
-		LOCK;
-	}
-	if (_memRef) {
-		err = IOGeneralMemoryDescriptor::memoryReferenceSetPurgeable(_memRef, newState, oldState);
-	}
-	if (kIOMemoryThreadSafe & _flags) {
-		UNLOCK;
-	}
-
-	return err;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::setOwnership( task_t newOwner,
-    int newLedgerTag,
-    IOOptionBits newLedgerOptions )
-{
-	IOReturn      err = kIOReturnSuccess;
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		return kIOReturnNotAttached;
-	}
-
-	if (iokit_iomd_setownership_enabled == FALSE) {
-		return kIOReturnUnsupported;
-	}
-
-	if (_memRef) {
-		err = super::setOwnership(newOwner, newLedgerTag, newLedgerOptions);
-	} else {
-		err = kIOReturnUnsupported;
-	}
-
-	return err;
-}
-
-IOReturn
-IOMemoryDescriptor::setOwnership( task_t newOwner,
-    int newLedgerTag,
-    IOOptionBits newLedgerOptions )
-{
-	IOReturn err = kIOReturnNotReady;
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		return kIOReturnNotAttached;
-	}
-
-	if (iokit_iomd_setownership_enabled == FALSE) {
-		return kIOReturnUnsupported;
-	}
-
-	if (kIOMemoryThreadSafe & _flags) {
-		LOCK;
-	}
-	if (_memRef) {
-		err = IOGeneralMemoryDescriptor::memoryReferenceSetOwnership(_memRef, newOwner, newLedgerTag, newLedgerOptions);
-	} else {
-		IOMultiMemoryDescriptor * mmd;
-		IOSubMemoryDescriptor   * smd;
-		if ((smd = OSDynamicCast(IOSubMemoryDescriptor, this))) {
-			err = smd->setOwnership(newOwner, newLedgerTag, newLedgerOptions);
-		} else if ((mmd = OSDynamicCast(IOMultiMemoryDescriptor, this))) {
-			err = mmd->setOwnership(newOwner, newLedgerTag, newLedgerOptions);
-		}
-	}
-	if (kIOMemoryThreadSafe & _flags) {
-		UNLOCK;
-	}
-
-	return err;
-}
-
-
-uint64_t
-IOMemoryDescriptor::getDMAMapLength(uint64_t * offset)
-{
-	uint64_t length;
-
-	if (_memRef) {
-		length = IOGeneralMemoryDescriptor::memoryReferenceGetDMAMapLength(_memRef, offset);
-	} else {
-		IOByteCount       iterate, segLen;
-		IOPhysicalAddress sourceAddr, sourceAlign;
-
-		if (kIOMemoryThreadSafe & _flags) {
-			LOCK;
-		}
-		length = 0;
-		iterate = 0;
-		while ((sourceAddr = getPhysicalSegment(iterate, &segLen, _kIOMemorySourceSegment))) {
-			sourceAlign = (sourceAddr & page_mask);
-			if (offset && !iterate) {
-				*offset = sourceAlign;
-			}
-			length += round_page(sourceAddr + segLen) - trunc_page(sourceAddr);
-			iterate += segLen;
-		}
-		if (!iterate) {
-			length = getLength();
-			if (offset) {
-				*offset = 0;
-			}
-		}
-		if (kIOMemoryThreadSafe & _flags) {
-			UNLOCK;
-		}
-	}
-
-	return length;
-}
-
-IOReturn
-IOMemoryDescriptor::getPageCounts( IOByteCount * residentPageCount,
-    IOByteCount * dirtyPageCount,
-    IOByteCount * swappedPageCount )
-{
-	IOReturn err = kIOReturnNotReady;
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		return kIOReturnNotAttached;
-	}
-
-	if (kIOMemoryThreadSafe & _flags) {
-		LOCK;
-	}
-	if (_memRef) {
-		err = IOGeneralMemoryDescriptor::memoryReferenceGetPageCounts(_memRef, residentPageCount, dirtyPageCount, swappedPageCount);
-	} else {
-		IOMultiMemoryDescriptor * mmd;
-		IOSubMemoryDescriptor   * smd;
-		if ((smd = OSDynamicCast(IOSubMemoryDescriptor, this))) {
-			err = smd->getPageCounts(residentPageCount, dirtyPageCount, swappedPageCount);
-		} else if ((mmd = OSDynamicCast(IOMultiMemoryDescriptor, this))) {
-			err = mmd->getPageCounts(residentPageCount, dirtyPageCount, swappedPageCount);
-		}
-	}
-	if (kIOMemoryThreadSafe & _flags) {
-		UNLOCK;
-	}
-
-	return err;
-}
-
-IOReturn
-IOMemoryDescriptor::getPageCounts( IOByteCount * residentPageCount,
-    IOByteCount * dirtyPageCount )
-{
-	return getPageCounts(residentPageCount, dirtyPageCount, NULL);
-}
-
-
-#if defined(__arm64__)
-extern "C" void dcache_incoherent_io_flush64(addr64_t pa, unsigned int count, unsigned int remaining, unsigned int *res);
-extern "C" void dcache_incoherent_io_store64(addr64_t pa, unsigned int count, unsigned int remaining, unsigned int *res);
-#else /* defined(__arm64__) */
+IOPhysicalAddress IOMemoryDescriptor::getSourceSegment( IOByteCount   offset,
+                                                        IOByteCount * length )
+{
+    IOPhysicalAddress physAddr = 0;
+
+    if( prepare() == kIOReturnSuccess) {
+        physAddr = getPhysicalSegment( offset, length );
+        complete();
+    }
+
+    return( physAddr );
+}
+
+IOByteCount IOMemoryDescriptor::readBytes
+                (IOByteCount offset, void *bytes, IOByteCount length)
+{
+    addr64_t dstAddr = (addr64_t) (UInt32) bytes;
+    IOByteCount remaining;
+
+    // Assert that this entire I/O is withing the available range
+    assert(offset < _length);
+    assert(offset + length <= _length);
+    if (offset >= _length) {
+IOLog("IOGMD(%p): rB = o%lx, l%lx\n", this, offset, length);	// @@@ gvdl
+        return 0;
+    }
+
+    remaining = length = min(length, _length - offset);
+    while (remaining) {	// (process another target segment?)
+        addr64_t	srcAddr64;
+        IOByteCount	srcLen;
+
+        srcAddr64 = getPhysicalSegment64(offset, &srcLen);
+        if (!srcAddr64)
+            break;
+
+        // Clip segment length to remaining
+        if (srcLen > remaining)
+            srcLen = remaining;
+
+        copypv(srcAddr64, dstAddr, srcLen,
+                            cppvPsrc | cppvNoRefSrc | cppvFsnk | cppvKmap);
+
+        dstAddr   += srcLen;
+        offset    += srcLen;
+        remaining -= srcLen;
+    }
+
+    assert(!remaining);
+
+    return length - remaining;
+}
+
+IOByteCount IOMemoryDescriptor::writeBytes
+                (IOByteCount offset, const void *bytes, IOByteCount length)
+{
+    addr64_t srcAddr = (addr64_t) (UInt32) bytes;
+    IOByteCount remaining;
+
+    // Assert that this entire I/O is withing the available range
+    assert(offset < _length);
+    assert(offset + length <= _length);
+
+    assert( !(kIOMemoryPreparedReadOnly & _flags) );
+
+    if ( (kIOMemoryPreparedReadOnly & _flags) || offset >= _length) {
+IOLog("IOGMD(%p): wB = o%lx, l%lx\n", this, offset, length);	// @@@ gvdl
+        return 0;
+    }
+
+    remaining = length = min(length, _length - offset);
+    while (remaining) {	// (process another target segment?)
+        addr64_t    dstAddr64;
+        IOByteCount dstLen;
+
+        dstAddr64 = getPhysicalSegment64(offset, &dstLen);
+        if (!dstAddr64)
+            break;
+
+        // Clip segment length to remaining
+        if (dstLen > remaining)
+            dstLen = remaining;
+
+        copypv(srcAddr, (addr64_t) dstAddr64, dstLen,
+                            cppvPsnk | cppvFsnk | cppvNoRefSrc | cppvNoModSnk | cppvKmap);
+
+        srcAddr   += dstLen;
+        offset    += dstLen;
+        remaining -= dstLen;
+    }
+
+    assert(!remaining);
+
+    return length - remaining;
+}
+
+// osfmk/device/iokit_rpc.c
+extern "C" unsigned int IODefaultCacheBits(addr64_t pa);
+
+/* DEPRECATED */ void IOGeneralMemoryDescriptor::setPosition(IOByteCount position)
+/* DEPRECATED */ {
+                    panic("IOGMD::setPosition deprecated");
+/* DEPRECATED */ }
+
+IOPhysicalAddress IOGeneralMemoryDescriptor::getPhysicalSegment
+                        (IOByteCount offset, IOByteCount *lengthOfSegment)
+{
+    IOPhysicalAddress address = 0;
+    IOPhysicalLength  length  = 0;
+
+//  assert(offset <= _length);
+    if (offset < _length) // (within bounds?)
+    {
+        if ( (_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical) {
+            unsigned int ind;
+
+            // Physical address based memory descriptor
+
+            // Find offset within descriptor and make it relative
+            // to the current _range.
+            for (ind = 0 ; offset >= _ranges.p[ind].length; ind++ )
+                offset -= _ranges.p[ind].length;
+    
+            IOPhysicalRange cur = _ranges.p[ind];
+            address = cur.address + offset;
+            length  = cur.length  - offset;
+
+            // see how far we can coalesce ranges
+            for (++ind; ind < _rangesCount; ind++) {
+                cur =  _ranges.p[ind];
+        
+                if (address + length != cur.address)
+                    break;
+    
+                length += cur.length;
+            }
+
+            // @@@ gvdl: should be assert(address);
+            // but can't as NVidia GeForce creates a bogus physical mem
+	    assert(address
+		|| /* nvidia */ (!_ranges.p[0].address && 1 == _rangesCount));
+            assert(length);
+        }
+        else do {
+            // We need wiring & we are wired.
+            assert(_wireCount);
+
+            if (!_wireCount)
+	    {
+		panic("IOGMD: not wired for getPhysicalSegment()");
+                continue;
+	    }
+
+            assert(_memoryEntries);
+
+            ioGMDData * dataP = getDataP(_memoryEntries);
+            const ioPLBlock *ioplList = getIOPLList(dataP);
+            UInt ind, numIOPLs = getNumIOPL(_memoryEntries, dataP);
+            upl_page_info_t *pageList = getPageList(dataP);
+
+            assert(numIOPLs > 0);
+
+            // Scan through iopl info blocks looking for block containing offset
+            for (ind = 1; ind < numIOPLs; ind++) {
+                if (offset < ioplList[ind].fIOMDOffset)
+                    break;
+            }
+
+            // Go back to actual range as search goes past it
+            ioPLBlock ioplInfo = ioplList[ind - 1];
+
+            if (ind < numIOPLs)
+                length = ioplList[ind].fIOMDOffset;
+            else
+                length = _length;
+            length -= offset;			// Remainder within iopl
+
+            // Subtract offset till this iopl in total list
+            offset -= ioplInfo.fIOMDOffset;
+
+            // This is a mapped IOPL so we just need to compute an offset
+            // relative to the mapped base.
+            if (ioplInfo.fMappedBase) {
+                offset += (ioplInfo.fPageOffset & PAGE_MASK);
+                address = ptoa_32(ioplInfo.fMappedBase) + offset;
+                continue;
+            }
+
+            // Currently the offset is rebased into the current iopl.
+            // Now add the iopl 1st page offset.
+            offset += ioplInfo.fPageOffset;
+
+            // For external UPLs the fPageInfo field points directly to
+            // the upl's upl_page_info_t array.
+            if (ioplInfo.fFlags & kIOPLExternUPL)
+                pageList = (upl_page_info_t *) ioplInfo.fPageInfo;
+            else
+                pageList = &pageList[ioplInfo.fPageInfo];
+
+            // Check for direct device non-paged memory
+            if ( ioplInfo.fFlags & kIOPLOnDevice ) {
+                address = ptoa_32(pageList->phys_addr) + offset;
+                continue;
+            }
+
+            // Now we need compute the index into the pageList
+            ind = atop_32(offset);
+            offset &= PAGE_MASK;
+
+            IOPhysicalAddress pageAddr = pageList[ind].phys_addr;
+            address = ptoa_32(pageAddr) + offset;
+
+            // Check for the remaining data in this upl being longer than the
+            // remainder on the current page.  This should be checked for
+            // contiguous pages
+            if (length > PAGE_SIZE - offset) {
+                // See if the next page is contiguous.  Stop looking when we hit
+                // the end of this upl, which is indicated by the
+                // contigLength >= length.
+                IOByteCount contigLength = PAGE_SIZE - offset;
+
+                // Look for contiguous segment
+                while (contigLength < length
+                &&     ++pageAddr == pageList[++ind].phys_addr) {
+                    contigLength += PAGE_SIZE;
+                }
+                if (length > contigLength)
+                    length = contigLength;
+            }
+    
+            assert(address);
+            assert(length);
+
+        } while (0);
+
+        if (!address)
+            length = 0;
+    }
+
+    if (lengthOfSegment)
+        *lengthOfSegment = length;
+
+    return address;
+}
+
+addr64_t IOMemoryDescriptor::getPhysicalSegment64
+                        (IOByteCount offset, IOByteCount *lengthOfSegment)
+{
+    IOPhysicalAddress phys32;
+    IOByteCount	      length;
+    addr64_t 	      phys64;
+
+    phys32 = getPhysicalSegment(offset, lengthOfSegment);
+    if (!phys32)
+	return 0;
+
+    if (gIOSystemMapper)
+    {
+	IOByteCount origLen;
+
+	phys64 = gIOSystemMapper->mapAddr(phys32);
+	origLen = *lengthOfSegment;
+	length = page_size - (phys64 & (page_size - 1));
+	while ((length < origLen)
+	    && ((phys64 + length) == gIOSystemMapper->mapAddr(phys32 + length)))
+	    length += page_size;
+	if (length > origLen)
+	    length = origLen;
+
+	*lengthOfSegment = length;
+    }
+    else
+	phys64 = (addr64_t) phys32;
+
+    return phys64;
+}
+
+IOPhysicalAddress IOGeneralMemoryDescriptor::
+getSourceSegment(IOByteCount offset, IOByteCount *lengthOfSegment)
+{
+    IOPhysicalAddress address = 0;
+    IOPhysicalLength  length  = 0;
+    IOOptionBits      type    = _flags & kIOMemoryTypeMask;
+
+    assert(offset <= _length);
+
+    if ( type == kIOMemoryTypeUPL)
+	return super::getSourceSegment( offset, lengthOfSegment );
+    else if ( offset < _length ) // (within bounds?)
+    {
+        unsigned rangesIndex = 0;
+	Ranges vec = _ranges;
+	user_addr_t addr;
+
+	// Find starting address within the vector of ranges
+	for (;;) {
+	    getAddrLenForInd(addr, length, type, vec, rangesIndex);
+	    if (offset < length)
+		break;
+	    offset -= length; // (make offset relative)
+	    rangesIndex++;
+	} 
+
+	// Now that we have the starting range,
+	// lets find the last contiguous range
+        addr   += offset;
+        length -= offset;
+
+        for ( ++rangesIndex; rangesIndex < _rangesCount; rangesIndex++ ) {
+	    user_addr_t      newAddr;
+	    IOPhysicalLength newLen;
+
+	    getAddrLenForInd(newAddr, newLen, type, vec, rangesIndex);
+	    if (addr + length != newAddr)
+		break;
+	    length += newLen;
+	} 
+        if (addr)
+	    address = (IOPhysicalAddress) addr;	// Truncate address to 32bit
+	else
+	    length = 0;
+    }
+
+    if ( lengthOfSegment )  *lengthOfSegment = length;
+
+    return address;
+}
+
+/* DEPRECATED */ /* USE INSTEAD: map(), readBytes(), writeBytes() */
+/* DEPRECATED */ void * IOGeneralMemoryDescriptor::getVirtualSegment(IOByteCount offset,
+/* DEPRECATED */ 							IOByteCount * lengthOfSegment)
+/* DEPRECATED */ {
+                    if (_task == kernel_task)
+                        return (void *) getSourceSegment(offset, lengthOfSegment);
+                    else
+                        panic("IOGMD::getVirtualSegment deprecated");
+
+                    return 0;
+/* DEPRECATED */ }
+/* DEPRECATED */ /* USE INSTEAD: map(), readBytes(), writeBytes() */
+
+
+
+IOReturn IOMemoryDescriptor::setPurgeable( IOOptionBits newState,
+                                           IOOptionBits * oldState )
+{
+    IOReturn	  err = kIOReturnSuccess;
+    vm_purgable_t control;
+    int           state;
+
+    do 
+    {
+        if (!_memEntry)
+        {
+            err = kIOReturnNotReady;
+            break;
+        }
+
+        control = VM_PURGABLE_SET_STATE;
+        switch (newState)
+        {
+            case kIOMemoryPurgeableKeepCurrent:
+                control = VM_PURGABLE_GET_STATE;
+                break;
+
+            case kIOMemoryPurgeableNonVolatile:
+                state = VM_PURGABLE_NONVOLATILE;
+                break;
+            case kIOMemoryPurgeableVolatile:
+                state = VM_PURGABLE_VOLATILE;
+                break;
+            case kIOMemoryPurgeableEmpty:
+                state = VM_PURGABLE_EMPTY;
+                break;
+            default:
+                err = kIOReturnBadArgument;
+                break;
+        }
+
+        if (kIOReturnSuccess != err)
+            break;
+
+        err = mach_memory_entry_purgable_control((ipc_port_t) _memEntry, control, &state);
+
+        if (oldState)
+        {
+            if (kIOReturnSuccess == err)
+            {
+                switch (state)
+                {
+                    case VM_PURGABLE_NONVOLATILE:
+                        state = kIOMemoryPurgeableNonVolatile;
+                        break;
+                    case VM_PURGABLE_VOLATILE:
+                        state = kIOMemoryPurgeableVolatile;
+                        break;
+                    case VM_PURGABLE_EMPTY:
+                        state = kIOMemoryPurgeableEmpty;
+                        break;
+                    default:
+                        state = kIOMemoryPurgeableNonVolatile;
+                        err = kIOReturnNotReady;
+                        break;
+                }
+                *oldState = state;
+            }
+        }
+    }
+    while (false);
+
+    return (err);
+}
+
 extern "C" void dcache_incoherent_io_flush64(addr64_t pa, unsigned int count);
 extern "C" void dcache_incoherent_io_store64(addr64_t pa, unsigned int count);
-#endif /* defined(__arm64__) */
-
-static void
-SetEncryptOp(addr64_t pa, unsigned int count)
-{
-	ppnum_t page, end;
-
-	page = (ppnum_t) atop_64(round_page_64(pa));
-	end  = (ppnum_t) atop_64(trunc_page_64(pa + count));
-	for (; page < end; page++) {
-		pmap_clear_noencrypt(page);
-	}
-}
-
-static void
-ClearEncryptOp(addr64_t pa, unsigned int count)
-{
-	ppnum_t page, end;
-
-	page = (ppnum_t) atop_64(round_page_64(pa));
-	end  = (ppnum_t) atop_64(trunc_page_64(pa + count));
-	for (; page < end; page++) {
-		pmap_set_noencrypt(page);
-	}
-}
-
-IOReturn
-IOMemoryDescriptor::performOperation( IOOptionBits options,
-    IOByteCount offset, IOByteCount length )
-{
-	IOByteCount remaining;
-	unsigned int res;
-	void (*func)(addr64_t pa, unsigned int count) = NULL;
-#if defined(__arm64__)
-	void (*func_ext)(addr64_t pa, unsigned int count, unsigned int remaining, unsigned int *result) = NULL;
-#endif
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		return kIOReturnNotAttached;
-	}
-
-	switch (options) {
-	case kIOMemoryIncoherentIOFlush:
-#if defined(__arm64__)
-		func_ext = &dcache_incoherent_io_flush64;
-#if __ARM_COHERENT_IO__
-		func_ext(0, 0, 0, &res);
-		return kIOReturnSuccess;
-#else /* __ARM_COHERENT_IO__ */
-		break;
-#endif /* __ARM_COHERENT_IO__ */
-#else /* defined(__arm64__) */
-		func = &dcache_incoherent_io_flush64;
-		break;
-#endif /* defined(__arm64__) */
-	case kIOMemoryIncoherentIOStore:
-#if defined(__arm64__)
-		func_ext = &dcache_incoherent_io_store64;
-#if __ARM_COHERENT_IO__
-		func_ext(0, 0, 0, &res);
-		return kIOReturnSuccess;
-#else /* __ARM_COHERENT_IO__ */
-		break;
-#endif /* __ARM_COHERENT_IO__ */
-#else /* defined(__arm64__) */
-		func = &dcache_incoherent_io_store64;
-		break;
-#endif /* defined(__arm64__) */
-
-	case kIOMemorySetEncrypted:
-		func = &SetEncryptOp;
-		break;
-	case kIOMemoryClearEncrypted:
-		func = &ClearEncryptOp;
-		break;
-	}
-
-#if defined(__arm64__)
-	if ((func == NULL) && (func_ext == NULL)) {
-		return kIOReturnUnsupported;
-	}
-#else /* defined(__arm64__) */
-	if (!func) {
-		return kIOReturnUnsupported;
-	}
-#endif /* defined(__arm64__) */
-
-	if (kIOMemoryThreadSafe & _flags) {
-		LOCK;
-	}
-
-	res = 0x0UL;
-	remaining = length = IOMin(length, getLength() - offset);
-	while (remaining) {
-		// (process another target segment?)
-		addr64_t    dstAddr64;
-		IOByteCount dstLen;
-
-		dstAddr64 = getPhysicalSegment(offset, &dstLen, kIOMemoryMapperNone);
-		if (!dstAddr64) {
-			break;
-		}
-
-		// Clip segment length to remaining
-		if (dstLen > remaining) {
-			dstLen = remaining;
-		}
-		if (dstLen > (UINT_MAX - PAGE_SIZE + 1)) {
-			dstLen = (UINT_MAX - PAGE_SIZE + 1);
-		}
-		if (remaining > UINT_MAX) {
-			remaining = UINT_MAX;
-		}
-
-#if defined(__arm64__)
-		if (func) {
-			(*func)(dstAddr64, (unsigned int) dstLen);
-		}
-		if (func_ext) {
-			(*func_ext)(dstAddr64, (unsigned int) dstLen, (unsigned int) remaining, &res);
-			if (res != 0x0UL) {
-				remaining = 0;
-				break;
-			}
-		}
-#else /* defined(__arm64__) */
-		(*func)(dstAddr64, (unsigned int) dstLen);
-#endif /* defined(__arm64__) */
-
-		offset    += dstLen;
-		remaining -= dstLen;
-	}
-
-	if (kIOMemoryThreadSafe & _flags) {
-		UNLOCK;
-	}
-
-	return remaining ? kIOReturnUnderrun : kIOReturnSuccess;
-}
-
-/*
- *
- */
-
-#if defined(__i386__) || defined(__x86_64__)
-
-extern vm_offset_t kc_highest_nonlinkedit_vmaddr;
-
-/* XXX: By extending io_kernel_static_end to the highest virtual address in the KC,
- * we're opening up this path to IOMemoryDescriptor consumers who can now create UPLs to
- * kernel non-text data -- should we just add another range instead?
- */
-#define io_kernel_static_start  vm_kernel_stext
-#define io_kernel_static_end    (kc_highest_nonlinkedit_vmaddr ? kc_highest_nonlinkedit_vmaddr : vm_kernel_etext)
-
-#elif defined(__arm64__)
-
-extern vm_offset_t              static_memory_end;
-
-#if defined(__arm64__)
-#define io_kernel_static_start vm_kext_base
-#else /* defined(__arm64__) */
-#define io_kernel_static_start vm_kernel_stext
-#endif /* defined(__arm64__) */
-
-#define io_kernel_static_end    static_memory_end
-
+
+IOReturn IOMemoryDescriptor::performOperation( IOOptionBits options,
+                                                IOByteCount offset, IOByteCount length )
+{
+    IOByteCount remaining;
+    void (*func)(addr64_t pa, unsigned int count) = 0;
+
+    switch (options)
+    {
+        case kIOMemoryIncoherentIOFlush:
+            func = &dcache_incoherent_io_flush64;
+            break;
+        case kIOMemoryIncoherentIOStore:
+            func = &dcache_incoherent_io_store64;
+            break;
+    }
+
+    if (!func)
+        return (kIOReturnUnsupported);
+
+    remaining = length = min(length, getLength() - offset);
+    while (remaining)
+    // (process another target segment?)
+    {
+        addr64_t    dstAddr64;
+        IOByteCount dstLen;
+
+        dstAddr64 = getPhysicalSegment64(offset, &dstLen);
+        if (!dstAddr64)
+            break;
+
+        // Clip segment length to remaining
+        if (dstLen > remaining)
+            dstLen = remaining;
+
+	(*func)(dstAddr64, dstLen);
+
+        offset    += dstLen;
+        remaining -= dstLen;
+    }
+
+    return (remaining ? kIOReturnUnderrun : kIOReturnSuccess);
+}
+
+#ifdef __ppc__
+extern vm_offset_t		static_memory_end;
+#define io_kernel_static_end	static_memory_end
 #else
-#error io_kernel_static_end is undefined for this architecture
+extern vm_offset_t		first_avail;
+#define io_kernel_static_end	first_avail
 #endif
 
 static kern_return_t
 io_get_kernel_static_upl(
-	vm_map_t                /* map */,
-	uintptr_t               offset,
-	upl_size_t              *upl_size,
-	unsigned int            *page_offset,
-	upl_t                   *upl,
-	upl_page_info_array_t   page_list,
-	unsigned int            *count,
-	ppnum_t                 *highest_page)
-{
-	unsigned int pageCount, page;
-	ppnum_t phys;
-	ppnum_t highestPage = 0;
-
-	pageCount = atop_32(round_page(*upl_size + (page_mask & offset)));
-	if (pageCount > *count) {
-		pageCount = *count;
+	vm_map_t		/* map */,
+	vm_address_t		offset,
+	vm_size_t		*upl_size,
+	upl_t			*upl,
+	upl_page_info_array_t	page_list,
+	unsigned int		*count)
+{
+    unsigned int pageCount, page;
+    ppnum_t phys;
+
+    pageCount = atop_32(*upl_size);
+    if (pageCount > *count)
+	pageCount = *count;
+
+    *upl = NULL;
+
+    for (page = 0; page < pageCount; page++)
+    {
+	phys = pmap_find_phys(kernel_pmap, ((addr64_t)offset) + ptoa_64(page));
+	if (!phys)
+	    break;
+	page_list[page].phys_addr = phys;
+	page_list[page].pageout	  = 0;
+	page_list[page].absent	  = 0;
+	page_list[page].dirty	  = 0;
+	page_list[page].precious  = 0;
+	page_list[page].device	  = 0;
+    }
+
+    return ((page >= pageCount) ? kIOReturnSuccess : kIOReturnVMError);
+}
+
+IOReturn IOGeneralMemoryDescriptor::wireVirtual(IODirection forDirection)
+{
+    IOOptionBits type = _flags & kIOMemoryTypeMask;
+    IOReturn error = kIOReturnNoMemory;
+    ioGMDData *dataP;
+    ppnum_t mapBase = 0;
+    IOMapper *mapper;
+    ipc_port_t sharedMem = (ipc_port_t) _memEntry;
+
+    assert(!_wireCount);
+    assert(kIOMemoryTypeVirtual == type || kIOMemoryTypeUIO == type);
+
+    if (_pages >= gIOMaximumMappedIOPageCount)
+	return kIOReturnNoResources;
+
+    dataP = getDataP(_memoryEntries);
+    mapper = dataP->fMapper;
+    if (mapper && _pages)
+        mapBase = mapper->iovmAlloc(_pages);
+
+    // Note that appendBytes(NULL) zeros the data up to the
+    // desired length.
+    _memoryEntries->appendBytes(0, dataP->fPageCnt * sizeof(upl_page_info_t));
+    dataP = 0;	// May no longer be valid so lets not get tempted.
+
+    if (forDirection == kIODirectionNone)
+        forDirection = _direction;
+
+    int uplFlags;    // This Mem Desc's default flags for upl creation
+    switch (forDirection)
+    {
+    case kIODirectionOut:
+        // Pages do not need to be marked as dirty on commit
+        uplFlags = UPL_COPYOUT_FROM;
+        _flags |= kIOMemoryPreparedReadOnly;
+        break;
+
+    case kIODirectionIn:
+    default:
+        uplFlags = 0;	// i.e. ~UPL_COPYOUT_FROM
+        break;
+    }
+    uplFlags |= UPL_SET_IO_WIRE | UPL_SET_LITE;
+
+    // Find the appropriate vm_map for the given task
+    vm_map_t curMap;
+    if (_task == kernel_task && (kIOMemoryBufferPageable & _flags))
+        curMap = 0;
+    else
+        { curMap = get_task_map(_task); }
+
+    // Iterate over the vector of virtual ranges
+    Ranges vec = _ranges;
+    unsigned int pageIndex = 0;
+    IOByteCount mdOffset = 0;
+    for (UInt range = 0; range < _rangesCount; range++) {
+        ioPLBlock iopl;
+	user_addr_t startPage;
+        IOByteCount numBytes;
+
+	// Get the startPage address and length of vec[range]
+	getAddrLenForInd(startPage, numBytes, type, vec, range);
+	iopl.fPageOffset = (short) startPage & PAGE_MASK;
+	numBytes += iopl.fPageOffset;
+	startPage = trunc_page_64(startPage);
+
+	if (mapper)
+	    iopl.fMappedBase = mapBase + pageIndex;
+	else
+	    iopl.fMappedBase = 0;
+
+	// Iterate over the current range, creating UPLs
+        while (numBytes) {
+            dataP = getDataP(_memoryEntries);
+	    vm_address_t kernelStart = (vm_address_t) startPage;
+            vm_map_t theMap;
+	    if (curMap)
+		theMap = curMap;
+	    else if (!sharedMem) {
+		assert(_task == kernel_task);
+		theMap = IOPageableMapForAddress(kernelStart);
+	    }
+	    else
+		theMap = NULL;
+
+            upl_page_info_array_t pageInfo = getPageList(dataP);
+            int ioplFlags = uplFlags;
+            upl_page_list_ptr_t baseInfo = &pageInfo[pageIndex];
+
+            vm_size_t ioplSize = round_page_32(numBytes);
+            unsigned int numPageInfo = atop_32(ioplSize);
+
+	    if (theMap == kernel_map && kernelStart < io_kernel_static_end) {
+		error = io_get_kernel_static_upl(theMap, 
+						kernelStart,
+						&ioplSize,
+						&iopl.fIOPL,
+						baseInfo,
+						&numPageInfo);
+	    }
+	    else if (sharedMem) {
+		error = memory_object_iopl_request(sharedMem, 
+						ptoa_32(pageIndex),
+						&ioplSize,
+						&iopl.fIOPL,
+						baseInfo,
+						&numPageInfo,
+						&ioplFlags);
+	    }
+	    else {
+		assert(theMap);
+		error = vm_map_create_upl(theMap,
+						startPage,
+						&ioplSize,
+						&iopl.fIOPL,
+						baseInfo,
+						&numPageInfo,
+						&ioplFlags);
+	    }
+
+            assert(ioplSize);
+            if (error != KERN_SUCCESS)
+                goto abortExit;
+
+            error = kIOReturnNoMemory;
+
+            if (baseInfo->device) {
+                numPageInfo = 1;
+                iopl.fFlags  = kIOPLOnDevice;
+                // Don't translate device memory at all 
+		if (mapper && mapBase) {
+		    mapper->iovmFree(mapBase, _pages);
+		    mapBase = 0;
+		    iopl.fMappedBase = 0;
+		}
+            }
+            else {
+                iopl.fFlags = 0;
+                if (mapper)
+                    mapper->iovmInsert(mapBase, pageIndex,
+                                       baseInfo, numPageInfo);
+            }
+
+            iopl.fIOMDOffset = mdOffset;
+            iopl.fPageInfo = pageIndex;
+
+	    if ((_flags & kIOMemoryAutoPrepare) && iopl.fIOPL)
+	    {
+		upl_commit(iopl.fIOPL, 0, 0);
+		upl_deallocate(iopl.fIOPL);
+		iopl.fIOPL = 0;
+	    }
+
+            if (!_memoryEntries->appendBytes(&iopl, sizeof(iopl))) {
+                // Clean up partial created and unsaved iopl
+                if (iopl.fIOPL) {
+                    upl_abort(iopl.fIOPL, 0);
+                    upl_deallocate(iopl.fIOPL);
+                }
+                goto abortExit;
+            }
+
+            // Check for a multiple iopl's in one virtual range
+            pageIndex += numPageInfo;
+            mdOffset -= iopl.fPageOffset;
+            if (ioplSize < numBytes) {
+                numBytes -= ioplSize;
+                startPage += ioplSize;
+                mdOffset += ioplSize;
+                iopl.fPageOffset = 0;
+		if (mapper)
+		    iopl.fMappedBase = mapBase + pageIndex;
+            }
+            else {
+                mdOffset += numBytes;
+                break;
+            }
+        }
+    }
+
+    return kIOReturnSuccess;
+
+abortExit:
+    {
+        dataP = getDataP(_memoryEntries);
+        UInt done = getNumIOPL(_memoryEntries, dataP);
+        ioPLBlock *ioplList = getIOPLList(dataP);
+    
+        for (UInt range = 0; range < done; range++)
+	{
+	    if (ioplList[range].fIOPL) {
+             upl_abort(ioplList[range].fIOPL, 0);
+             upl_deallocate(ioplList[range].fIOPL);
+	    }
 	}
-	*upl_size = (upl_size_t) ptoa_64(pageCount);
-
-	*upl = NULL;
-	*page_offset = ((unsigned int) page_mask & offset);
-
-	for (page = 0; page < pageCount; page++) {
-		phys = pmap_find_phys(kernel_pmap, ((addr64_t)offset) + ptoa_64(page));
-		if (!phys) {
-			break;
-		}
-		page_list[page].phys_addr = phys;
-		page_list[page].free_when_done = 0;
-		page_list[page].absent    = 0;
-		page_list[page].dirty     = 0;
-		page_list[page].precious  = 0;
-		page_list[page].device    = 0;
-		if (phys > highestPage) {
-			highestPage = phys;
-		}
-	}
-
-	*highest_page = highestPage;
-
-	return (page >= pageCount) ? kIOReturnSuccess : kIOReturnVMError;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::wireVirtual(IODirection forDirection)
-{
-	IOOptionBits type = _flags & kIOMemoryTypeMask;
-	IOReturn error = kIOReturnSuccess;
-	ioGMDData *dataP;
-	upl_page_info_array_t pageInfo;
-	ppnum_t mapBase;
-	vm_tag_t tag = VM_KERN_MEMORY_NONE;
-	mach_vm_size_t numBytesWired = 0;
-
-	assert(kIOMemoryTypeVirtual == type || kIOMemoryTypeVirtual64 == type
-	    || kIOMemoryTypeUIO == type || kIOMemoryTypeVnode == type);
-
-	if ((kIODirectionOutIn & forDirection) == kIODirectionNone) {
-		forDirection = (IODirection) (forDirection | getDirection());
-	}
-
-	dataP = getDataP(_memoryEntries);
-	upl_control_flags_t uplFlags; // This Mem Desc's default flags for upl creation
-	switch (kIODirectionOutIn & forDirection) {
-	case kIODirectionOut:
-		// Pages do not need to be marked as dirty on commit
-		uplFlags = UPL_COPYOUT_FROM;
-		dataP->fDMAAccess = kIODMAMapReadAccess;
-		break;
-
-	case kIODirectionIn:
-		dataP->fDMAAccess = kIODMAMapWriteAccess;
-		uplFlags = 0;   // i.e. ~UPL_COPYOUT_FROM
-		break;
-
-	default:
-		dataP->fDMAAccess = kIODMAMapReadAccess | kIODMAMapWriteAccess;
-		uplFlags = 0;   // i.e. ~UPL_COPYOUT_FROM
-		break;
-	}
-
-	if (_wireCount) {
-		if ((kIOMemoryPreparedReadOnly & _flags) && !(UPL_COPYOUT_FROM & uplFlags)) {
-			OSReportWithBacktrace("IOMemoryDescriptor 0x%zx prepared read only",
-			    (size_t)VM_KERNEL_ADDRPERM(this));
-			error = kIOReturnNotWritable;
-		}
-	} else {
-		IOTimeStampIntervalConstantFiltered traceInterval(IODBG_MDESC(IOMDESC_WIRE), VM_KERNEL_ADDRHIDE(this), forDirection);
-		IOMapper *mapper;
-
-		mapper = dataP->fMapper;
-		dataP->fMappedBaseValid = dataP->fMappedBase = 0;
-
-		uplFlags |= UPL_SET_IO_WIRE | UPL_SET_LITE;
-		tag = _kernelTag;
-		if (VM_KERN_MEMORY_NONE == tag) {
-			tag = IOMemoryTag(kernel_map);
-		}
-
-		if (kIODirectionPrepareToPhys32 & forDirection) {
-			if (!mapper) {
-				uplFlags |= UPL_NEED_32BIT_ADDR;
-			}
-			if (dataP->fDMAMapNumAddressBits > 32) {
-				dataP->fDMAMapNumAddressBits = 32;
-			}
-		}
-		if (kIODirectionPrepareNoFault    & forDirection) {
-			uplFlags |= UPL_REQUEST_NO_FAULT;
-		}
-		if (kIODirectionPrepareNoZeroFill & forDirection) {
-			uplFlags |= UPL_NOZEROFILLIO;
-		}
-		if (kIODirectionPrepareNonCoherent & forDirection) {
-			uplFlags |= UPL_REQUEST_FORCE_COHERENCY;
-		}
-
-		mapBase = 0;
-
-		// Note that appendBytes(NULL) zeros the data up to the desired length
-		size_t uplPageSize = dataP->fPageCnt * sizeof(upl_page_info_t);
-		if (uplPageSize > ((unsigned int)uplPageSize)) {
-			error = kIOReturnNoMemory;
-			traceInterval.setEndArg2(error);
-			return error;
-		}
-		if (!_memoryEntries->appendBytes(NULL, uplPageSize)) {
-			error = kIOReturnNoMemory;
-			traceInterval.setEndArg2(error);
-			return error;
-		}
-		dataP = NULL;
-
-		// Find the appropriate vm_map for the given task
-		vm_map_t curMap;
-		if ((NULL != _memRef) || ((_task == kernel_task && (kIOMemoryBufferPageable & _flags)))) {
-			curMap = NULL;
-		} else {
-			curMap = get_task_map(_task);
-		}
-
-		// Iterate over the vector of virtual ranges
-		Ranges vec = _ranges;
-		unsigned int pageIndex  = 0;
-		IOByteCount mdOffset    = 0;
-		ppnum_t highestPage     = 0;
-		bool         byteAlignUPL;
-
-		IOMemoryEntry * memRefEntry = NULL;
-		if (_memRef) {
-			memRefEntry = &_memRef->entries[0];
-			byteAlignUPL = (0 != (MAP_MEM_USE_DATA_ADDR & _memRef->prot));
-		} else {
-			byteAlignUPL = true;
-		}
-
-		for (UInt range = 0; mdOffset < _length; range++) {
-			ioPLBlock iopl;
-			mach_vm_address_t startPage, startPageOffset;
-			mach_vm_size_t    numBytes;
-			ppnum_t highPage = 0;
-
-			if (_memRef) {
-				if (range >= _memRef->count) {
-					panic("memRefEntry");
-				}
-				memRefEntry = &_memRef->entries[range];
-				numBytes    = memRefEntry->size;
-				startPage   = -1ULL;
-				if (byteAlignUPL) {
-					startPageOffset = 0;
-				} else {
-					startPageOffset = (memRefEntry->start & PAGE_MASK);
-				}
-			} else {
-				// Get the startPage address and length of vec[range]
-				getAddrLenForInd(startPage, numBytes, type, vec, range, _task);
-				if (byteAlignUPL) {
-					startPageOffset = 0;
-				} else {
-					startPageOffset = startPage & PAGE_MASK;
-					startPage = trunc_page_64(startPage);
-				}
-			}
-			iopl.fPageOffset = (typeof(iopl.fPageOffset))startPageOffset;
-			numBytes += startPageOffset;
-
-			if (mapper) {
-				iopl.fMappedPage = mapBase + pageIndex;
-			} else {
-				iopl.fMappedPage = 0;
-			}
-
-			// Iterate over the current range, creating UPLs
-			while (numBytes) {
-				vm_address_t kernelStart = (vm_address_t)vm_memtag_canonicalize_kernel(startPage);
-				vm_map_t theMap;
-				if (curMap) {
-					theMap = curMap;
-					startPage = vm_memtag_canonicalize(curMap, startPage);
-				} else if (_memRef) {
-					theMap = NULL;
-				} else {
-					assert(_task == kernel_task);
-					theMap = IOPageableMapForAddress(kernelStart);
-				}
-
-				// ioplFlags is an in/out parameter
-				upl_control_flags_t ioplFlags = uplFlags;
-				dataP = getDataP(_memoryEntries);
-				pageInfo = getPageList(dataP);
-				upl_page_list_ptr_t baseInfo = &pageInfo[pageIndex];
-
-				mach_vm_size_t ioplPhysSize;
-				upl_size_t     ioplSize;
-				unsigned int   numPageInfo;
-
-				if (_memRef) {
-					error = mach_memory_entry_map_size(memRefEntry->entry, NULL /*physical*/, 0, memRefEntry->size, &ioplPhysSize);
-					DEBUG4K_IOKIT("_memRef %p memRefEntry %p entry %p startPage 0x%llx numBytes 0x%llx ioplPhysSize 0x%llx\n", _memRef, memRefEntry, memRefEntry->entry, startPage, numBytes, ioplPhysSize);
-				} else {
-					error = vm_map_range_physical_size(theMap, startPage, numBytes, &ioplPhysSize);
-					DEBUG4K_IOKIT("_memRef %p theMap %p startPage 0x%llx numBytes 0x%llx ioplPhysSize 0x%llx\n", _memRef, theMap, startPage, numBytes, ioplPhysSize);
-				}
-				if (error != KERN_SUCCESS) {
-					if (_memRef) {
-						DEBUG4K_ERROR("_memRef %p memRefEntry %p entry %p theMap %p startPage 0x%llx numBytes 0x%llx error 0x%x\n", _memRef, memRefEntry, memRefEntry->entry, theMap, startPage, numBytes, error);
-					} else {
-						DEBUG4K_ERROR("_memRef %p theMap %p startPage 0x%llx numBytes 0x%llx error 0x%x\n", _memRef, theMap, startPage, numBytes, error);
-					}
-					printf("entry size error %d\n", error);
-					goto abortExit;
-				}
-				ioplPhysSize    = (ioplPhysSize <= MAX_UPL_SIZE_BYTES) ? ioplPhysSize : MAX_UPL_SIZE_BYTES;
-				numPageInfo = atop_32(ioplPhysSize);
-				if (byteAlignUPL) {
-					if (numBytes > ioplPhysSize) {
-						ioplSize = ((typeof(ioplSize))ioplPhysSize);
-					} else {
-						ioplSize = ((typeof(ioplSize))numBytes);
-					}
-				} else {
-					ioplSize = ((typeof(ioplSize))ioplPhysSize);
-				}
-
-				if (_memRef) {
-					memory_object_offset_t entryOffset;
-
-					entryOffset = mdOffset;
-					if (byteAlignUPL) {
-						entryOffset = (entryOffset - memRefEntry->offset);
-					} else {
-						entryOffset = (entryOffset - iopl.fPageOffset - memRefEntry->offset);
-					}
-					if (ioplSize > (memRefEntry->size - entryOffset)) {
-						ioplSize =  ((typeof(ioplSize))(memRefEntry->size - entryOffset));
-					}
-					error = memory_object_iopl_request(memRefEntry->entry,
-					    entryOffset,
-					    &ioplSize,
-					    &iopl.fIOPL,
-					    baseInfo,
-					    &numPageInfo,
-					    &ioplFlags,
-					    tag);
-				} else if ((theMap == kernel_map)
-				    && (kernelStart >= io_kernel_static_start)
-				    && (kernelStart < io_kernel_static_end)) {
-					error = io_get_kernel_static_upl(theMap,
-					    kernelStart,
-					    &ioplSize,
-					    &iopl.fPageOffset,
-					    &iopl.fIOPL,
-					    baseInfo,
-					    &numPageInfo,
-					    &highPage);
-				} else {
-					assert(theMap);
-					assert(startPage == vm_memtag_canonicalize(theMap, startPage));
-
-					error = vm_map_create_upl(theMap,
-					    startPage,
-					    (upl_size_t*)&ioplSize,
-					    &iopl.fIOPL,
-					    baseInfo,
-					    &numPageInfo,
-					    &ioplFlags,
-					    tag);
-				}
-
-				if (error != KERN_SUCCESS) {
-					traceInterval.setEndArg2(error);
-					DEBUG4K_ERROR("UPL create error 0x%x theMap %p (kernel:%d) _memRef %p startPage 0x%llx ioplSize 0x%x\n", error, theMap, (theMap == kernel_map), _memRef, startPage, ioplSize);
-					goto abortExit;
-				}
-
-				assert(ioplSize);
-
-				if (iopl.fIOPL) {
-					highPage = upl_get_highest_page(iopl.fIOPL);
-				}
-				if (highPage > highestPage) {
-					highestPage = highPage;
-				}
-
-				if (baseInfo->device) {
-					numPageInfo = 1;
-					iopl.fFlags = kIOPLOnDevice;
-				} else {
-					iopl.fFlags = 0;
-				}
-
-				if (byteAlignUPL) {
-					if (iopl.fIOPL) {
-						DEBUG4K_UPL("startPage 0x%llx numBytes 0x%llx iopl.fPageOffset 0x%x upl_get_data_offset(%p) 0x%llx\n", startPage, numBytes, iopl.fPageOffset, iopl.fIOPL, upl_get_data_offset(iopl.fIOPL));
-						iopl.fPageOffset = (typeof(iopl.fPageOffset))upl_get_data_offset(iopl.fIOPL);
-					}
-					if (startPage != (mach_vm_address_t)-1) {
-						// assert(iopl.fPageOffset == (startPage & PAGE_MASK));
-						startPage -= iopl.fPageOffset;
-					}
-					ioplSize = ((typeof(ioplSize))ptoa_64(numPageInfo));
-					numBytes += iopl.fPageOffset;
-				}
-
-				iopl.fIOMDOffset = mdOffset;
-				iopl.fPageInfo = pageIndex;
-
-				if (!_memoryEntries->appendBytes(&iopl, sizeof(iopl))) {
-					// Clean up partial created and unsaved iopl
-					if (iopl.fIOPL) {
-						upl_abort(iopl.fIOPL, 0);
-						upl_deallocate(iopl.fIOPL);
-					}
-					error = kIOReturnNoMemory;
-					traceInterval.setEndArg2(error);
-					goto abortExit;
-				}
-				dataP = NULL;
-
-				// Check for a multiple iopl's in one virtual range
-				pageIndex += numPageInfo;
-				mdOffset -= iopl.fPageOffset;
-				numBytesWired += ioplSize;
-				if (ioplSize < numBytes) {
-					numBytes -= ioplSize;
-					if (startPage != (mach_vm_address_t)-1) {
-						startPage += ioplSize;
-					}
-					mdOffset += ioplSize;
-					iopl.fPageOffset = 0;
-					if (mapper) {
-						iopl.fMappedPage = mapBase + pageIndex;
-					}
-				} else {
-					mdOffset += numBytes;
-					break;
-				}
-			}
-		}
-
-		_highestPage = highestPage;
-		DEBUG4K_IOKIT("-> _highestPage 0x%x\n", _highestPage);
-
-		if (UPL_COPYOUT_FROM & uplFlags) {
-			_flags |= kIOMemoryPreparedReadOnly;
-		}
-		traceInterval.setEndCodes(numBytesWired, error);
-	}
-
-#if IOTRACKING
-	if (!(_flags & kIOMemoryAutoPrepare) && (kIOReturnSuccess == error)) {
-		dataP = getDataP(_memoryEntries);
-		if (!dataP->fWireTracking.link.next) {
-			IOTrackingAdd(gIOWireTracking, &dataP->fWireTracking, ptoa(_pages), false, tag);
-		}
-	}
-#endif /* IOTRACKING */
-
-	return error;
-
-abortExit:
-	{
-		dataP = getDataP(_memoryEntries);
-		UInt done = getNumIOPL(_memoryEntries, dataP);
-		ioPLBlock *ioplList = getIOPLList(dataP);
-
-		for (UInt ioplIdx = 0; ioplIdx < done; ioplIdx++) {
-			if (ioplList[ioplIdx].fIOPL) {
-				upl_abort(ioplList[ioplIdx].fIOPL, 0);
-				upl_deallocate(ioplList[ioplIdx].fIOPL);
-			}
-		}
-		_memoryEntries->setLength(computeDataSize(0, 0));
-	}
-
-	if (error == KERN_FAILURE) {
-		error = kIOReturnCannotWire;
-	} else if (error == KERN_MEMORY_ERROR) {
-		error = kIOReturnNoResources;
-	}
-
-	return error;
-}
-
-bool
-IOGeneralMemoryDescriptor::initMemoryEntries(size_t size, IOMapper * mapper)
-{
-	ioGMDData * dataP;
-
-	if (size > UINT_MAX) {
-		return false;
-	}
-	if (!_memoryEntries) {
-		_memoryEntries = _IOMemoryDescriptorMixedData::withCapacity(size);
-		if (!_memoryEntries) {
-			return false;
-		}
-	} else if (!_memoryEntries->initWithCapacity(size)) {
-		return false;
-	}
-
-	_memoryEntries->appendBytes(NULL, computeDataSize(0, 0));
-	dataP = getDataP(_memoryEntries);
-
-	if (mapper == kIOMapperWaitSystem) {
-		IOMapper::checkForSystemMapper();
-		mapper = IOMapper::gSystem;
-	}
-	dataP->fMapper               = mapper;
-	dataP->fPageCnt              = 0;
-	dataP->fMappedBase           = 0;
-	dataP->fDMAMapNumAddressBits = 64;
-	dataP->fDMAMapAlignment      = 0;
-	dataP->fPreparationID        = kIOPreparationIDUnprepared;
-	dataP->fCompletionError      = false;
-	dataP->fMappedBaseValid      = false;
-
-	return true;
-}
-
-IOReturn
-IOMemoryDescriptor::dmaMap(
-	IOMapper                    * mapper,
-	IOMemoryDescriptor          * memory,
-	IODMACommand                * command,
-	const IODMAMapSpecification * mapSpec,
-	uint64_t                      offset,
-	uint64_t                      length,
-	uint64_t                    * mapAddress,
-	uint64_t                    * mapLength)
-{
-	IOReturn err;
-	uint32_t mapOptions;
-
-	mapOptions = 0;
-	mapOptions |= kIODMAMapReadAccess;
-	if (!(kIOMemoryPreparedReadOnly & _flags)) {
-		mapOptions |= kIODMAMapWriteAccess;
-	}
-
-	err = mapper->iovmMapMemory(memory, offset, length, mapOptions,
-	    mapSpec, command, NULL, mapAddress, mapLength);
-
-	if (kIOReturnSuccess == err) {
-		dmaMapRecord(mapper, command, *mapLength);
-	}
-
-	return err;
-}
-
-void
-IOMemoryDescriptor::dmaMapRecord(
-	IOMapper                    * mapper,
-	IODMACommand                * command,
-	uint64_t                      mapLength)
-{
-	IOTimeStampIntervalConstantFiltered traceInterval(IODBG_MDESC(IOMDESC_DMA_MAP), VM_KERNEL_ADDRHIDE(this));
-	kern_allocation_name_t alloc;
-	int16_t                prior;
-
-	if ((alloc = mapper->fAllocName) /* && mapper != IOMapper::gSystem */) {
-		kern_allocation_update_size(mapper->fAllocName, mapLength, NULL);
-	}
-
-	if (!command) {
-		return;
-	}
-	prior = OSAddAtomic16(1, &_dmaReferences);
-	if (!prior) {
-		if (alloc && (VM_KERN_MEMORY_NONE != _kernelTag)) {
-			_mapName  = alloc;
-			mapLength = _length;
-			kern_allocation_update_subtotal(alloc, _kernelTag, mapLength);
-		} else {
-			_mapName = NULL;
-		}
-	}
-}
-
-IOReturn
-IOMemoryDescriptor::dmaUnmap(
-	IOMapper                    * mapper,
-	IODMACommand                * command,
-	uint64_t                      offset,
-	uint64_t                      mapAddress,
-	uint64_t                      mapLength)
-{
-	IOTimeStampIntervalConstantFiltered traceInterval(IODBG_MDESC(IOMDESC_DMA_UNMAP), VM_KERNEL_ADDRHIDE(this));
-	IOReturn ret;
-	kern_allocation_name_t alloc;
-	kern_allocation_name_t mapName;
-	int16_t prior;
-
-	mapName = NULL;
-	prior = 0;
-	if (command) {
-		mapName = _mapName;
-		if (_dmaReferences) {
-			prior = OSAddAtomic16(-1, &_dmaReferences);
-		} else {
-			panic("_dmaReferences underflow");
-		}
-	}
-
-	if (!mapLength) {
-		traceInterval.setEndArg1(kIOReturnSuccess);
-		return kIOReturnSuccess;
-	}
-
-	ret = mapper->iovmUnmapMemory(this, command, mapAddress, mapLength);
-
-	if ((alloc = mapper->fAllocName)) {
-		kern_allocation_update_size(alloc, -mapLength, NULL);
-		if ((1 == prior) && mapName && (VM_KERN_MEMORY_NONE != _kernelTag)) {
-			mapLength = _length;
-			kern_allocation_update_subtotal(mapName, _kernelTag, -mapLength);
-		}
-	}
-
-	traceInterval.setEndArg1(ret);
-	return ret;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::dmaMap(
-	IOMapper                    * mapper,
-	IOMemoryDescriptor          * memory,
-	IODMACommand                * command,
-	const IODMAMapSpecification * mapSpec,
-	uint64_t                      offset,
-	uint64_t                      length,
-	uint64_t                    * mapAddress,
-	uint64_t                    * mapLength)
-{
-	IOReturn          err = kIOReturnSuccess;
-	ioGMDData *       dataP;
-	IOOptionBits      type = _flags & kIOMemoryTypeMask;
-	mach_vm_address_t range0Addr = 0;
-	mach_vm_size_t    range0Len = 0;
-	Ranges            vec = _ranges;
-
-	*mapAddress = 0;
-	if (kIOMemoryHostOnly & _flags) {
-		return kIOReturnSuccess;
-	}
-	if (kIOMemoryRemote & _flags) {
-		return kIOReturnNotAttached;
-	}
-
-
-	if ((type == kIOMemoryTypePhysical) || (type == kIOMemoryTypePhysical64)
-	    || offset || (length != _length)) {
-		err = super::dmaMap(mapper, memory, command, mapSpec, offset, length, mapAddress, mapLength);
-	} else if (_memoryEntries && _pages && (dataP = getDataP(_memoryEntries))) {
-		const ioPLBlock * ioplList = getIOPLList(dataP);
-		upl_page_info_t * pageList;
-		uint32_t          mapOptions = 0;
-
-		IODMAMapSpecification mapSpec;
-		bzero(&mapSpec, sizeof(mapSpec));
-		mapSpec.numAddressBits = dataP->fDMAMapNumAddressBits;
-		mapSpec.alignment = dataP->fDMAMapAlignment;
-
-		// For external UPLs the fPageInfo field points directly to
-		// the upl's upl_page_info_t array.
-		if (ioplList->fFlags & kIOPLExternUPL) {
-			pageList = (upl_page_info_t *) ioplList->fPageInfo;
-			mapOptions |= kIODMAMapPagingPath;
-		} else {
-			pageList = getPageList(dataP);
-		}
-
-		if ((_length == ptoa_64(_pages)) && !(page_mask & ioplList->fPageOffset)) {
-			mapOptions |= kIODMAMapPageListFullyOccupied;
-		}
-
-		assert(dataP->fDMAAccess);
-		mapOptions |= dataP->fDMAAccess;
-
-		// Check for direct device non-paged memory
-		if (ioplList->fFlags & kIOPLOnDevice) {
-			mapOptions |= kIODMAMapPhysicallyContiguous;
-		}
-
-		IODMAMapPageList dmaPageList =
-		{
-			.pageOffset    = (uint32_t)(ioplList->fPageOffset & page_mask),
-			.pageListCount = _pages,
-			.pageList      = &pageList[0]
-		};
-		err = mapper->iovmMapMemory(memory, offset, length, mapOptions, &mapSpec,
-		    command, &dmaPageList, mapAddress, mapLength);
-
-		if (kIOReturnSuccess == err) {
-			dmaMapRecord(mapper, command, *mapLength);
-		}
-	}
-
-	return err;
+	(void) _memoryEntries->initWithBytes(dataP, sizeof(ioGMDData)); // == setLength()
+
+        if (mapper && mapBase)
+            mapper->iovmFree(mapBase, _pages);
+    }
+
+    return error;
 }
 
 /*
@@ -5021,56 +1648,21 @@
  * the memory after the I/O transfer finishes.  This method needn't
  * called for non-pageable memory.
  */
-
-IOReturn
-IOGeneralMemoryDescriptor::prepare(IODirection forDirection)
-{
-	IOReturn     error    = kIOReturnSuccess;
-	IOOptionBits type = _flags & kIOMemoryTypeMask;
-	IOTimeStampIntervalConstantFiltered traceInterval(IODBG_MDESC(IOMDESC_PREPARE), VM_KERNEL_ADDRHIDE(this), forDirection);
-
-	if ((kIOMemoryTypePhysical == type) || (kIOMemoryTypePhysical64 == type)) {
-		traceInterval.setEndArg1(kIOReturnSuccess);
-		return kIOReturnSuccess;
-	}
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		traceInterval.setEndArg1(kIOReturnNotAttached);
-		return kIOReturnNotAttached;
-	}
-
-	if (_prepareLock) {
-		IOLockLock(_prepareLock);
-	}
-
-	if (kIOMemoryTypeVirtual == type || kIOMemoryTypeVirtual64 == type
-	    || kIOMemoryTypeUIO == type || kIOMemoryTypeVnode == type) {
-		if ((forDirection & kIODirectionPrepareAvoidThrottling) && NEED_TO_HARD_THROTTLE_THIS_TASK()) {
-			error = kIOReturnNotReady;
-			goto finish;
-		}
-		error = wireVirtual(forDirection);
-	}
-
-	if (kIOReturnSuccess == error) {
-		if (1 == ++_wireCount) {
-			if (kIOMemoryClearEncrypt & _flags) {
-				performOperation(kIOMemoryClearEncrypted, 0, _length);
-			}
-
-			ktraceEmitPhysicalSegments();
-		}
-	}
-
-finish:
-
-	if (_prepareLock) {
-		IOLockUnlock(_prepareLock);
-	}
-	traceInterval.setEndArg1(error);
-
-	return error;
+IOReturn IOGeneralMemoryDescriptor::prepare(IODirection forDirection)
+{
+    IOReturn error    = kIOReturnSuccess;
+    IOOptionBits type = _flags & kIOMemoryTypeMask;
+
+    if (!_wireCount
+    && (kIOMemoryTypeVirtual == type || kIOMemoryTypeUIO == type) ) {
+        error = wireVirtual(forDirection);
+        if (error)
+            return error;
+    }
+
+    _wireCount++;
+
+    return kIOReturnSuccess;
 }
 
 /*
@@ -5081,965 +1673,935 @@
  * issued; the prepare() and complete() must occur in pairs, before
  * before and after an I/O transfer involving pageable memory.
  */
-
-IOReturn
-IOGeneralMemoryDescriptor::complete(IODirection forDirection)
-{
+ 
+IOReturn IOGeneralMemoryDescriptor::complete(IODirection /* forDirection */)
+{
+    assert(_wireCount);
+
+    if (!_wireCount)
+        return kIOReturnSuccess;
+
+    _wireCount--;
+    if (!_wireCount) {
 	IOOptionBits type = _flags & kIOMemoryTypeMask;
-	ioGMDData  * dataP;
-	IOTimeStampIntervalConstantFiltered traceInterval(IODBG_MDESC(IOMDESC_COMPLETE), VM_KERNEL_ADDRHIDE(this), forDirection);
-
-	if ((kIOMemoryTypePhysical == type) || (kIOMemoryTypePhysical64 == type)) {
-		traceInterval.setEndArg1(kIOReturnSuccess);
-		return kIOReturnSuccess;
+
+        if (kIOMemoryTypePhysical == type) {
+            /* kIOMemoryTypePhysical */
+            // DO NOTHING
+        }
+        else {
+            ioGMDData * dataP = getDataP(_memoryEntries);
+            ioPLBlock *ioplList = getIOPLList(dataP);
+	    UInt count = getNumIOPL(_memoryEntries, dataP);
+
+            if (dataP->fMapper && _pages && ioplList[0].fMappedBase)
+                dataP->fMapper->iovmFree(ioplList[0].fMappedBase, _pages);
+
+            // Only complete iopls that we created which are for TypeVirtual
+            if (kIOMemoryTypeVirtual == type || kIOMemoryTypeUIO == type) {
+                for (UInt ind = 0; ind < count; ind++)
+		    if (ioplList[ind].fIOPL) {
+			 upl_commit(ioplList[ind].fIOPL, 0, 0);
+			 upl_deallocate(ioplList[ind].fIOPL);
+		    }
+            }
+
+            (void) _memoryEntries->initWithBytes(dataP, sizeof(ioGMDData)); // == setLength()
+        }
+    }
+    return kIOReturnSuccess;
+}
+
+IOReturn IOGeneralMemoryDescriptor::doMap(
+	vm_map_t		addressMap,
+	IOVirtualAddress *	atAddress,
+	IOOptionBits		options,
+	IOByteCount		sourceOffset,
+	IOByteCount		length )
+{
+    kern_return_t kr;
+    ipc_port_t sharedMem = (ipc_port_t) _memEntry;
+
+    IOOptionBits type = _flags & kIOMemoryTypeMask;
+    Ranges vec = _ranges;
+
+    user_addr_t range0Addr = 0;
+    IOByteCount range0Len = 0;
+
+    if (vec.v)
+	getAddrLenForInd(range0Addr, range0Len, type, vec, 0);
+
+    // mapping source == dest? (could be much better)
+    if( _task
+    && (addressMap == get_task_map(_task)) && (options & kIOMapAnywhere)
+    && (1 == _rangesCount) && (0 == sourceOffset)
+    && range0Addr && (length <= range0Len) ) {
+	if (sizeof(user_addr_t) > 4 && ((UInt64) range0Addr) >> 32)
+	    return kIOReturnOverrun;	// Doesn't fit in 32bit return field
+	else {
+	    *atAddress = range0Addr;
+	    return( kIOReturnSuccess );
 	}
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		traceInterval.setEndArg1(kIOReturnNotAttached);
-		return kIOReturnNotAttached;
+    }
+
+    if( 0 == sharedMem) {
+
+        vm_size_t size = ptoa_32(_pages);
+
+        if( _task) {
+#ifndef i386
+            memory_object_size_t actualSize = size;
+            kr = mach_make_memory_entry_64(get_task_map(_task),
+                        &actualSize, range0Addr,
+                        VM_PROT_READ | VM_PROT_WRITE, &sharedMem,
+                        NULL );
+
+            if( (KERN_SUCCESS == kr) && (actualSize != round_page_32(size))) {
+#if IOASSERT
+                IOLog("mach_make_memory_entry_64 (%08llx) size (%08lx:%08x)\n",
+                            range0Addr, (UInt32) actualSize, size);
+#endif
+                kr = kIOReturnVMError;
+                ipc_port_release_send( sharedMem );
+            }
+
+            if( KERN_SUCCESS != kr)
+#endif /* !i386 */
+                sharedMem = MACH_PORT_NULL;
+
+        } else do {
+
+            memory_object_t 	pager;
+	    unsigned int    	flags = 0;
+    	    addr64_t		pa;
+    	    IOPhysicalLength	segLen;
+
+	    pa = getPhysicalSegment64( sourceOffset, &segLen );
+
+            if( !reserved) {
+                reserved = IONew( ExpansionData, 1 );
+                if( !reserved)
+                    continue;
+            }
+            reserved->pagerContig = (1 == _rangesCount);
+	    reserved->memory = this;
+
+	    /*What cache mode do we need*/
+            switch(options & kIOMapCacheMask ) {
+
+		case kIOMapDefaultCache:
+		default:
+		    flags = IODefaultCacheBits(pa);
+		    break;
+	
+		case kIOMapInhibitCache:
+		    flags = DEVICE_PAGER_CACHE_INHIB | 
+				    DEVICE_PAGER_COHERENT | DEVICE_PAGER_GUARDED;
+		    break;
+	
+		case kIOMapWriteThruCache:
+		    flags = DEVICE_PAGER_WRITE_THROUGH |
+				    DEVICE_PAGER_COHERENT | DEVICE_PAGER_GUARDED;
+		    break;
+
+		case kIOMapCopybackCache:
+		    flags = DEVICE_PAGER_COHERENT;
+		    break;
+
+		case kIOMapWriteCombineCache:
+		    flags = DEVICE_PAGER_CACHE_INHIB |
+				    DEVICE_PAGER_COHERENT;
+		    break;
+            }
+
+	    flags |= reserved->pagerContig ? DEVICE_PAGER_CONTIGUOUS : 0;
+
+            pager = device_pager_setup( (memory_object_t) 0, (int) reserved, 
+								size, flags);
+            assert( pager );
+
+            if( pager) {
+                kr = mach_memory_object_memory_entry_64( (host_t) 1, false /*internal*/, 
+                            size, VM_PROT_READ | VM_PROT_WRITE, pager, &sharedMem );
+
+                assert( KERN_SUCCESS == kr );
+                if( KERN_SUCCESS != kr) {
+		    device_pager_deallocate( pager );
+                    pager = MACH_PORT_NULL;
+                    sharedMem = MACH_PORT_NULL;
+                }
+            }
+	    if( pager && sharedMem)
+		reserved->devicePager    = pager;
+	    else {
+		IODelete( reserved, ExpansionData, 1 );
+		reserved = 0;
+	    }
+
+        } while( false );
+
+        _memEntry = (void *) sharedMem;
+    }
+
+
+#ifndef i386
+    if( 0 == sharedMem)
+      kr = kIOReturnVMError;
+    else
+#endif
+      kr = super::doMap( addressMap, atAddress,
+                           options, sourceOffset, length );
+
+    return( kr );
+}
+
+IOReturn IOGeneralMemoryDescriptor::doUnmap(
+	vm_map_t		addressMap,
+	IOVirtualAddress	logical,
+	IOByteCount		length )
+{
+    // could be much better
+    if( _task && (addressMap == get_task_map(_task)) && (1 == _rangesCount)) {
+
+	IOOptionBits type = _flags & kIOMemoryTypeMask;
+	user_addr_t range0Addr;
+	IOByteCount range0Len;
+
+	getAddrLenForInd(range0Addr, range0Len, type, _ranges, 0);
+	if (logical == range0Addr && length <= range0Len)
+	    return( kIOReturnSuccess );
+    }
+
+    return( super::doUnmap( addressMap, logical, length ));
+}
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+OSDefineMetaClassAndAbstractStructors( IOMemoryMap, OSObject )
+
+/* inline function implementation */
+IOPhysicalAddress IOMemoryMap::getPhysicalAddress()
+    { return( getPhysicalSegment( 0, 0 )); }
+
+
+#undef super
+#define super IOMemoryMap
+
+OSDefineMetaClassAndStructors(_IOMemoryMap, IOMemoryMap)
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+bool _IOMemoryMap::initCompatible(
+	IOMemoryDescriptor *	_memory,
+	IOMemoryMap *		_superMap,
+        IOByteCount		_offset,
+        IOByteCount		_length )
+{
+
+    if( !super::init())
+	return( false);
+
+    if( (_offset + _length) > _superMap->getLength())
+	return( false);
+
+    _memory->retain();
+    memory	= _memory;
+    _superMap->retain();
+    superMap 	= _superMap;
+
+    offset	= _offset;
+    if( _length)
+        length	= _length;
+    else
+        length	= _memory->getLength();
+
+    options	= superMap->getMapOptions();
+    logical	= superMap->getVirtualAddress() + offset;
+
+    return( true );
+}
+
+bool _IOMemoryMap::initWithDescriptor(
+        IOMemoryDescriptor *	_memory,
+        task_t			intoTask,
+        IOVirtualAddress	toAddress,
+        IOOptionBits		_options,
+        IOByteCount		_offset,
+        IOByteCount		_length )
+{
+    bool ok;
+    bool redir = ((kIOMapUnique|kIOMapReference) == ((kIOMapUnique|kIOMapReference) & _options));
+
+    if ((!_memory) || (!intoTask))
+	return( false);
+
+    if( (_offset + _length) > _memory->getLength())
+	return( false);
+
+    if (!redir)
+    {
+	if (!super::init())
+	    return(false);
+	addressMap  = get_task_map(intoTask);
+	if( !addressMap)
+	    return( false);
+	vm_map_reference(addressMap);
+	addressTask = intoTask;
+	logical	    = toAddress;
+	options     = _options;
+    }
+
+    _memory->retain();
+
+    offset	= _offset;
+    if( _length)
+        length	= _length;
+    else
+        length	= _memory->getLength();
+
+    if( options & kIOMapStatic)
+	ok = true;
+    else
+	ok = (kIOReturnSuccess == _memory->doMap( addressMap, &toAddress,
+						  _options, offset, length ));
+    if (ok || redir)
+    {
+	if (memory)
+	    memory->release();
+	memory	= _memory;
+	logical = toAddress;
+    }
+    else
+    {
+        _memory->release();
+	if (!redir)
+	{
+	    logical = 0;
+	    memory = 0;
+	    vm_map_deallocate(addressMap);
+	    addressMap = 0;
 	}
-
-	if (_prepareLock) {
-		IOLockLock(_prepareLock);
+    }
+
+    return( ok );
+}
+
+/* LP64todo - these need to expand */
+struct IOMemoryDescriptorMapAllocRef
+{
+    ipc_port_t		sharedMem;
+    vm_size_t		size;
+    vm_offset_t		mapped;
+    IOByteCount		sourceOffset;
+    IOOptionBits	options;
+};
+
+static kern_return_t IOMemoryDescriptorMapAlloc(vm_map_t map, void * _ref)
+{
+    IOMemoryDescriptorMapAllocRef * ref = (IOMemoryDescriptorMapAllocRef *)_ref;
+    IOReturn			    err;
+
+    do {
+        if( ref->sharedMem) {
+            vm_prot_t prot = VM_PROT_READ
+                            | ((ref->options & kIOMapReadOnly) ? 0 : VM_PROT_WRITE);
+
+            // set memory entry cache
+            vm_prot_t memEntryCacheMode = prot | MAP_MEM_ONLY;
+            switch (ref->options & kIOMapCacheMask)
+            {
+		case kIOMapInhibitCache:
+                    SET_MAP_MEM(MAP_MEM_IO, memEntryCacheMode);
+                    break;
+	
+		case kIOMapWriteThruCache:
+                    SET_MAP_MEM(MAP_MEM_WTHRU, memEntryCacheMode);
+                    break;
+
+		case kIOMapWriteCombineCache:
+                    SET_MAP_MEM(MAP_MEM_WCOMB, memEntryCacheMode);
+                    break;
+
+		case kIOMapCopybackCache:
+                    SET_MAP_MEM(MAP_MEM_COPYBACK, memEntryCacheMode);
+                    break;
+
+		case kIOMapDefaultCache:
+		default:
+                    SET_MAP_MEM(MAP_MEM_NOOP, memEntryCacheMode);
+                    break;
+            }
+
+            vm_size_t unused = 0;
+
+            err = mach_make_memory_entry( NULL /*unused*/, &unused, 0 /*unused*/, 
+                                            memEntryCacheMode, NULL, ref->sharedMem );
+            if (KERN_SUCCESS != err)
+                IOLog("MAP_MEM_ONLY failed %d\n", err);
+
+            err = vm_map( map,
+                            &ref->mapped,
+                            ref->size, 0 /* mask */, 
+                            (( ref->options & kIOMapAnywhere ) ? VM_FLAGS_ANYWHERE : VM_FLAGS_FIXED)
+                            | VM_MAKE_TAG(VM_MEMORY_IOKIT), 
+                            ref->sharedMem, ref->sourceOffset,
+                            false, // copy
+                            prot, // cur
+                            prot, // max
+                            VM_INHERIT_NONE);
+
+            if( KERN_SUCCESS != err) {
+                ref->mapped = 0;
+                continue;
+            }
+    
+        } else {
+    
+            err = vm_allocate( map, &ref->mapped, ref->size,
+                            ((ref->options & kIOMapAnywhere) ? VM_FLAGS_ANYWHERE : VM_FLAGS_FIXED)
+                            | VM_MAKE_TAG(VM_MEMORY_IOKIT) );
+    
+            if( KERN_SUCCESS != err) {
+                ref->mapped = 0;
+                continue;
+            }
+    
+            // we have to make sure that these guys don't get copied if we fork.
+            err = vm_inherit( map, ref->mapped, ref->size, VM_INHERIT_NONE);
+            assert( KERN_SUCCESS == err );
+        }
+
+    } while( false );
+
+    return( err );
+}
+
+
+IOReturn IOMemoryDescriptor::doMap(
+	vm_map_t		addressMap,
+	IOVirtualAddress *	atAddress,
+	IOOptionBits		options,
+	IOByteCount		sourceOffset,
+	IOByteCount		length )
+{
+    IOReturn		err = kIOReturnSuccess;
+    memory_object_t	pager;
+    vm_address_t	logical;
+    IOByteCount		pageOffset;
+    IOPhysicalAddress	sourceAddr;
+    IOMemoryDescriptorMapAllocRef	ref;
+
+    ref.sharedMem	= (ipc_port_t) _memEntry;
+    ref.sourceOffset	= sourceOffset;
+    ref.options		= options;
+
+    do {
+
+        if( 0 == length)
+            length = getLength();
+
+	sourceAddr = getSourceSegment( sourceOffset, NULL );
+	pageOffset = sourceAddr - trunc_page_32( sourceAddr );
+
+	ref.size = round_page_32( length + pageOffset );
+
+	if ((kIOMapReference|kIOMapUnique) == ((kIOMapReference|kIOMapUnique) & options))
+	{
+	    upl_t	  redirUPL2;
+	    vm_size_t	  size;
+	    int		  flags;
+
+	    _IOMemoryMap * mapping = (_IOMemoryMap *) *atAddress;
+	    ref.mapped = mapping->getVirtualAddress();
+    
+	    if (!_memEntry)
+	    {
+		err = kIOReturnNotReadable;
+		continue;
+	    }
+
+	    size = length;
+	    flags = UPL_COPYOUT_FROM | UPL_SET_INTERNAL 
+			| UPL_SET_LITE | UPL_SET_IO_WIRE | UPL_BLOCK_ACCESS;
+
+	    if (KERN_SUCCESS != memory_object_iopl_request((ipc_port_t) _memEntry, 0, &size, &redirUPL2,
+					    NULL, NULL,
+					    &flags))
+		redirUPL2 = NULL;
+
+	    err = upl_transpose(redirUPL2, mapping->redirUPL);
+	    if (kIOReturnSuccess != err)
+	    {
+		IOLog("upl_transpose(%x)\n", err);
+		err = kIOReturnSuccess;
+	    }
+
+	    if (redirUPL2)
+	    {
+		upl_commit(redirUPL2, NULL, 0);
+		upl_deallocate(redirUPL2);
+		redirUPL2 = 0;
+	    }
+	    {
+		// swap the memEntries since they now refer to different vm_objects
+		void * me = _memEntry;
+		_memEntry = mapping->memory->_memEntry;
+		mapping->memory->_memEntry = me;
+	    }
 	}
-	do{
-		assert(_wireCount);
-		if (!_wireCount) {
-			break;
+	else
+	{
+    
+	    logical = *atAddress;
+	    if( options & kIOMapAnywhere) 
+		// vm_map looks for addresses above here, even when VM_FLAGS_ANYWHERE
+		ref.mapped = 0;
+	    else {
+		ref.mapped = trunc_page_32( logical );
+		if( (logical - ref.mapped) != pageOffset) {
+		    err = kIOReturnVMError;
+		    continue;
 		}
-		dataP = getDataP(_memoryEntries);
-		if (!dataP) {
-			break;
-		}
-
-		if (kIODirectionCompleteWithError & forDirection) {
-			dataP->fCompletionError = true;
-		}
-
-		if ((kIOMemoryClearEncrypt & _flags) && (1 == _wireCount)) {
-			performOperation(kIOMemorySetEncrypted, 0, _length);
-		}
-
-		_wireCount--;
-		if (!_wireCount || (kIODirectionCompleteWithDataValid & forDirection)) {
-			ioPLBlock *ioplList = getIOPLList(dataP);
-			UInt ind, count = getNumIOPL(_memoryEntries, dataP);
-
-			if (_wireCount) {
-				// kIODirectionCompleteWithDataValid & forDirection
-				if (kIOMemoryTypeVirtual == type || kIOMemoryTypeVirtual64 == type || kIOMemoryTypeUIO == type || kIOMemoryTypeVnode == type) {
-					vm_tag_t tag;
-					tag = (typeof(tag))getVMTag(kernel_map);
-					for (ind = 0; ind < count; ind++) {
-						if (ioplList[ind].fIOPL) {
-							iopl_valid_data(ioplList[ind].fIOPL, tag);
-						}
-					}
-				}
-			} else {
-				if (_dmaReferences) {
-					panic("complete() while dma active");
-				}
-
-				if (dataP->fMappedBaseValid) {
-					dmaUnmap(dataP->fMapper, NULL, 0, dataP->fMappedBase, dataP->fMappedLength);
-					dataP->fMappedBaseValid = dataP->fMappedBase = 0;
-				}
-#if IOTRACKING
-				if (dataP->fWireTracking.link.next) {
-					IOTrackingRemove(gIOWireTracking, &dataP->fWireTracking, ptoa(_pages));
-				}
-#endif /* IOTRACKING */
-				// Only complete iopls that we created which are for TypeVirtual
-				if (kIOMemoryTypeVirtual == type || kIOMemoryTypeVirtual64 == type || kIOMemoryTypeUIO == type || kIOMemoryTypeVnode == type) {
-					for (ind = 0; ind < count; ind++) {
-						if (ioplList[ind].fIOPL) {
-							if (dataP->fCompletionError) {
-								upl_abort(ioplList[ind].fIOPL, 0 /*!UPL_ABORT_DUMP_PAGES*/);
-							} else {
-								upl_commit(ioplList[ind].fIOPL, NULL, 0);
-							}
-							upl_deallocate(ioplList[ind].fIOPL);
-						}
-					}
-				} else if (kIOMemoryTypeUPL == type) {
-					upl_set_referenced(ioplList[0].fIOPL, false);
-				}
-
-				_memoryEntries->setLength(computeDataSize(0, 0));
-
-				dataP->fPreparationID = kIOPreparationIDUnprepared;
-				_flags &= ~kIOMemoryPreparedReadOnly;
-
-				if (kdebug_debugid_explicitly_enabled(IODBG_IOMDPA(IOMDPA_UNMAPPED))) {
-					IOTimeStampConstantFiltered(IODBG_IOMDPA(IOMDPA_UNMAPPED), getDescriptorID(), VM_KERNEL_ADDRHIDE(this));
-				}
-			}
-		}
-	}while (false);
-
-	if (_prepareLock) {
-		IOLockUnlock(_prepareLock);
+	    }
+    
+	    if( ref.sharedMem && (addressMap == kernel_map) && (kIOMemoryBufferPageable & _flags))
+		err = IOIteratePageableMaps( ref.size, &IOMemoryDescriptorMapAlloc, &ref );
+	    else
+		err = IOMemoryDescriptorMapAlloc( addressMap, &ref );
 	}
 
-	traceInterval.setEndArg1(kIOReturnSuccess);
-	return kIOReturnSuccess;
-}
-
-IOOptionBits
-IOGeneralMemoryDescriptor::memoryReferenceCreateOptions(IOOptionBits options, IOMemoryMap * mapping)
-{
-	IOOptionBits createOptions = 0;
-
-	if (!(kIOMap64Bit & options)) {
-		panic("IOMemoryDescriptor::makeMapping !64bit");
+        if( err != KERN_SUCCESS)
+            continue;
+
+        if( reserved)
+            pager = (memory_object_t) reserved->devicePager;
+        else
+            pager = MACH_PORT_NULL;
+
+        if( !ref.sharedMem || pager )
+            err = handleFault( pager, addressMap, ref.mapped, sourceOffset, length, options );
+
+    } while( false );
+
+    if( err != KERN_SUCCESS) {
+        if( ref.mapped)
+            doUnmap( addressMap, ref.mapped, ref.size );
+        *atAddress = NULL;
+    } else
+        *atAddress = ref.mapped + pageOffset;
+
+    return( err );
+}
+
+enum {
+    kIOMemoryRedirected	= 0x00010000
+};
+
+IOReturn IOMemoryDescriptor::handleFault(
+        void *			_pager,
+	vm_map_t		addressMap,
+	IOVirtualAddress	address,
+	IOByteCount		sourceOffset,
+	IOByteCount		length,
+        IOOptionBits		options )
+{
+    IOReturn		err = kIOReturnSuccess;
+    memory_object_t	pager = (memory_object_t) _pager;
+    vm_size_t		size;
+    vm_size_t		bytes;
+    vm_size_t		page;
+    IOByteCount		pageOffset;
+    IOByteCount		pagerOffset;
+    IOPhysicalLength	segLen;
+    addr64_t		physAddr;
+
+    if( !addressMap) {
+
+        if( kIOMemoryRedirected & _flags) {
+#ifdef DEBUG
+            IOLog("sleep mem redirect %p, %lx\n", this, sourceOffset);
+#endif
+            do {
+	    	SLEEP;
+            } while( kIOMemoryRedirected & _flags );
+        }
+
+        return( kIOReturnSuccess );
+    }
+
+    physAddr = getPhysicalSegment64( sourceOffset, &segLen );
+    assert( physAddr );
+    pageOffset = physAddr - trunc_page_64( physAddr );
+    pagerOffset = sourceOffset;
+
+    size = length + pageOffset;
+    physAddr -= pageOffset;
+
+    segLen += pageOffset;
+    bytes = size;
+    do {
+	// in the middle of the loop only map whole pages
+	if( segLen >= bytes)
+	    segLen = bytes;
+	else if( segLen != trunc_page_32( segLen))
+	    err = kIOReturnVMError;
+        if( physAddr != trunc_page_64( physAddr))
+	    err = kIOReturnBadArgument;
+
+#ifdef DEBUG
+	if( kIOLogMapping & gIOKitDebug)
+	    IOLog("_IOMemoryMap::map(%p) %08lx->%08qx:%08lx\n",
+                addressMap, address + pageOffset, physAddr + pageOffset,
+		segLen - pageOffset);
+#endif
+
+
+
+
+
+#ifdef i386  
+	/* i386 doesn't support faulting on device memory yet */
+	if( addressMap && (kIOReturnSuccess == err))
+            err = IOMapPages( addressMap, address, (IOPhysicalAddress) physAddr, segLen, options );
+        assert( KERN_SUCCESS == err );
+	if( err)
+	    break;
+#endif
+
+        if( pager) {
+            if( reserved && reserved->pagerContig) {
+                IOPhysicalLength	allLen;
+                addr64_t		allPhys;
+
+                allPhys = getPhysicalSegment64( 0, &allLen );
+                assert( allPhys );
+                err = device_pager_populate_object( pager, 0, allPhys >> PAGE_SHIFT, round_page_32(allLen) );
+
+            } else {
+
+	    for( page = 0;
+                     (page < segLen) && (KERN_SUCCESS == err);
+                     page += page_size) {
+                        err = device_pager_populate_object(pager, pagerOffset,
+                        	(ppnum_t)((physAddr + page) >> PAGE_SHIFT), page_size);
+			pagerOffset += page_size;
+                }
+            }
+            assert( KERN_SUCCESS == err );
+            if( err)
+                break;
+        }
+#ifndef i386
+	/*  *** ALERT *** */
+	/*  *** Temporary Workaround *** */
+
+	/* This call to vm_fault causes an early pmap level resolution	*/
+	/* of the mappings created above.  Need for this is in absolute	*/
+	/* violation of the basic tenet that the pmap layer is a cache.	*/
+	/* Further, it implies a serious I/O architectural violation on	*/
+	/* the part of some user of the mapping.  As of this writing, 	*/
+	/* the call to vm_fault is needed because the NVIDIA driver 	*/
+	/* makes a call to pmap_extract.  The NVIDIA driver needs to be	*/
+	/* fixed as soon as possible.  The NVIDIA driver should not 	*/
+	/* need to query for this info as it should know from the doMap	*/
+	/* call where the physical memory is mapped.  When a query is 	*/
+	/* necessary to find a physical mapping, it should be done 	*/
+	/* through an iokit call which includes the mapped memory 	*/
+	/* handle.  This is required for machine architecture independence.*/
+
+	if(!(kIOMemoryRedirected & _flags)) {
+		vm_fault(addressMap, 
+			 (vm_map_offset_t)address, 
+			 VM_PROT_READ|VM_PROT_WRITE, 
+			 FALSE, THREAD_UNINT, NULL, 
+			 (vm_map_offset_t)0);
 	}
-	if (!(kIOMapReadOnly & options)) {
-		createOptions |= kIOMemoryReferenceWrite;
-#if DEVELOPMENT || DEBUG
-		if ((kIODirectionOut == (kIODirectionOutIn & _flags))
-		    && (!reserved || (reserved->creator != mapping->fAddressTask))) {
-			OSReportWithBacktrace("warning: creating writable mapping from IOMemoryDescriptor(kIODirectionOut) - use kIOMapReadOnly or change direction");
-		}
+
+	/*  *** Temporary Workaround *** */
+	/*  *** ALERT *** */
 #endif
+	sourceOffset += segLen - pageOffset;
+	address += segLen;
+	bytes -= segLen;
+	pageOffset = 0;
+
+    } while( bytes
+	&& (physAddr = getPhysicalSegment64( sourceOffset, &segLen )));
+
+    if( bytes)
+        err = kIOReturnBadArgument;
+
+    return( err );
+}
+
+IOReturn IOMemoryDescriptor::doUnmap(
+	vm_map_t		addressMap,
+	IOVirtualAddress	logical,
+	IOByteCount		length )
+{
+    IOReturn	err;
+
+#ifdef DEBUG
+    if( kIOLogMapping & gIOKitDebug)
+	kprintf("IOMemoryDescriptor::doUnmap(%x) %08x:%08x\n",
+                addressMap, logical, length );
+#endif
+
+    if( true /* && (addressMap == kernel_map) || (addressMap == get_task_map(current_task()))*/) {
+
+        if( _memEntry && (addressMap == kernel_map) && (kIOMemoryBufferPageable & _flags))
+            addressMap = IOPageableMapForAddress( logical );
+
+        err = vm_deallocate( addressMap, logical, length );
+
+    } else
+        err = kIOReturnSuccess;
+
+    return( err );
+}
+
+IOReturn IOMemoryDescriptor::redirect( task_t safeTask, bool doRedirect )
+{
+    IOReturn		err = kIOReturnSuccess;
+    _IOMemoryMap *	mapping = 0;
+    OSIterator *	iter;
+
+    LOCK;
+
+    if( doRedirect)
+        _flags |= kIOMemoryRedirected;
+    else
+        _flags &= ~kIOMemoryRedirected;
+
+    do {
+	if( (iter = OSCollectionIterator::withCollection( _mappings))) {
+	    while( (mapping = (_IOMemoryMap *) iter->getNextObject()))
+		mapping->redirect( safeTask, doRedirect );
+
+	    iter->release();
 	}
-	return createOptions;
-}
-
-/*
- * Attempt to create any kIOMemoryMapCopyOnWrite named entry needed ahead of the global
- * lock taken in IOMemoryDescriptor::makeMapping() since it may allocate real pages on
- * creation.
- */
-
-IOMemoryMap *
-IOGeneralMemoryDescriptor::makeMapping(
-	IOMemoryDescriptor *    owner,
-	task_t                  __intoTask,
-	IOVirtualAddress        __address,
-	IOOptionBits            options,
-	IOByteCount             __offset,
-	IOByteCount             __length )
-{
-	IOReturn err = kIOReturnSuccess;
-	IOMemoryMap * mapping;
-
-	if ((kIOMemoryMapCopyOnWrite & _flags) && _task && !_memRef) {
-		struct IOMemoryReference * newRef;
-		err = memoryReferenceCreate(memoryReferenceCreateOptions(options, (IOMemoryMap *) __address), &newRef);
-		if (kIOReturnSuccess == err) {
-			if (!OSCompareAndSwapPtr(NULL, newRef, &_memRef)) {
-				memoryReferenceFree(newRef);
-			}
-		}
-	}
-	if (kIOReturnSuccess != err) {
-		return NULL;
-	}
-	mapping = IOMemoryDescriptor::makeMapping(
-		owner, __intoTask, __address, options, __offset, __length);
-
-#if IOTRACKING
-	if ((mapping == (IOMemoryMap *) __address)
-	    && (0 == (kIOMapStatic & mapping->fOptions))
-	    && (NULL == mapping->fSuperMap)
-	    && ((kIOTracking & gIOKitDebug) || _task)) {
-		// only dram maps in the default on development case
-		IOTrackingAddUser(gIOMapTracking, &mapping->fTracking, mapping->fLength);
-	}
-#endif /* IOTRACKING */
-
-	return mapping;
-}
-
-IOReturn
-IOGeneralMemoryDescriptor::doMap(
-	vm_map_t                __addressMap,
-	IOVirtualAddress *      __address,
-	IOOptionBits            options,
-	IOByteCount             __offset,
-	IOByteCount             __length )
-{
-	IOTimeStampIntervalConstantFiltered traceInterval(IODBG_MDESC(IOMDESC_MAP), VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(*__address), __length);
-	traceInterval.setEndArg1(kIOReturnSuccess);
-#ifndef __LP64__
-	if (!(kIOMap64Bit & options)) {
-		panic("IOGeneralMemoryDescriptor::doMap !64bit");
-	}
-#endif /* !__LP64__ */
-
-	kern_return_t  err;
-
-	IOMemoryMap *  mapping = (IOMemoryMap *) *__address;
-	mach_vm_size_t offset  = mapping->fOffset + __offset;
-	mach_vm_size_t length  = mapping->fLength;
-
-	IOOptionBits type = _flags & kIOMemoryTypeMask;
-	Ranges vec = _ranges;
-
-	mach_vm_address_t range0Addr = 0;
-	mach_vm_size_t    range0Len = 0;
-
-	if ((offset >= _length) || ((offset + length) > _length)) {
-		traceInterval.setEndArg1(kIOReturnBadArgument);
-		DEBUG4K_ERROR("map %p offset 0x%llx length 0x%llx _length 0x%llx kIOReturnBadArgument\n", __addressMap, offset, length, (uint64_t)_length);
-		// assert(offset == 0 && _length == 0 && length == 0);
-		return kIOReturnBadArgument;
-	}
-
-	assert(!(kIOMemoryRemote & _flags));
-	if (kIOMemoryRemote & _flags) {
-		return 0;
-	}
-
-	if (vec.v) {
-		getAddrLenForInd(range0Addr, range0Len, type, vec, 0, _task);
-	}
-
-	// mapping source == dest? (could be much better)
-	if (_task
-	    && (mapping->fAddressTask == _task)
-	    && (mapping->fAddressMap == get_task_map(_task))
-	    && (options & kIOMapAnywhere)
-	    && (!(kIOMapUnique & options))
-	    && (!(kIOMapGuardedMask & options))
-	    && (1 == _rangesCount)
-	    && (0 == offset)
-	    && range0Addr
-	    && (length <= range0Len)) {
-		mapping->fAddress = range0Addr;
-		mapping->fOptions |= kIOMapStatic;
-
-		return kIOReturnSuccess;
-	}
-
-	if (!_memRef) {
-		err = memoryReferenceCreate(memoryReferenceCreateOptions(options, mapping), &_memRef);
-		if (kIOReturnSuccess != err) {
-			traceInterval.setEndArg1(err);
-			DEBUG4K_ERROR("map %p err 0x%x\n", __addressMap, err);
-			return err;
-		}
-	}
-
-
-	memory_object_t pager;
-	pager = (memory_object_t) (reserved ? reserved->dp.devicePager : NULL);
-
-	// <upl_transpose //
-	if ((kIOMapReference | kIOMapUnique) == ((kIOMapReference | kIOMapUnique) & options)) {
-		do{
-			upl_t               redirUPL2;
-			upl_size_t          size;
-			upl_control_flags_t flags;
-			unsigned int        lock_count;
-
-			if (!_memRef || (1 != _memRef->count)) {
-				err = kIOReturnNotReadable;
-				DEBUG4K_ERROR("map %p err 0x%x\n", __addressMap, err);
-				break;
-			}
-
-			size = (upl_size_t) round_page(mapping->fLength);
-			flags = UPL_COPYOUT_FROM | UPL_SET_INTERNAL
-			    | UPL_SET_LITE | UPL_SET_IO_WIRE | UPL_BLOCK_ACCESS;
-
-			if (KERN_SUCCESS != memory_object_iopl_request(_memRef->entries[0].entry, 0, &size, &redirUPL2,
-			    NULL, NULL,
-			    &flags, (vm_tag_t) getVMTag(kernel_map))) {
-				redirUPL2 = NULL;
-			}
-
-			for (lock_count = 0;
-			    IORecursiveLockHaveLock(gIOMemoryLock);
-			    lock_count++) {
-				UNLOCK;
-			}
-			err = upl_transpose(redirUPL2, mapping->fRedirUPL);
-			for (;
-			    lock_count;
-			    lock_count--) {
-				LOCK;
-			}
-
-			if (kIOReturnSuccess != err) {
-				IOLog("upl_transpose(%x)\n", err);
-				err = kIOReturnSuccess;
-			}
-
-			if (redirUPL2) {
-				upl_commit(redirUPL2, NULL, 0);
-				upl_deallocate(redirUPL2);
-				redirUPL2 = NULL;
-			}
-			{
-				// swap the memEntries since they now refer to different vm_objects
-				IOMemoryReference * me = _memRef;
-				_memRef = mapping->fMemory->_memRef;
-				mapping->fMemory->_memRef = me;
-			}
-			if (pager) {
-				err = populateDevicePager( pager, mapping->fAddressMap, mapping->fAddress, offset, length, options );
-			}
-		}while (false);
-	}
-	// upl_transpose> //
-	else {
-		err = memoryReferenceMap(_memRef, mapping->fAddressMap, offset, length, options, &mapping->fAddress);
-		if (err) {
-			DEBUG4K_ERROR("map %p err 0x%x\n", mapping->fAddressMap, err);
-		}
-		if ((err == KERN_SUCCESS) && pager) {
-			err = populateDevicePager(pager, mapping->fAddressMap, mapping->fAddress, offset, length, options);
-
-			if (err != KERN_SUCCESS) {
-				doUnmap(mapping->fAddressMap, (IOVirtualAddress) mapping, 0);
-			} else if (kIOMapDefaultCache == (options & kIOMapCacheMask)) {
-				mapping->fOptions |= ((_flags & kIOMemoryBufferCacheMask) >> kIOMemoryBufferCacheShift);
-			}
-		}
-	}
-
-	traceInterval.setEndArg1(err);
-	if (err) {
-		DEBUG4K_ERROR("map %p err 0x%x\n", __addressMap, err);
-	}
-	return err;
-}
-
-#if IOTRACKING
-IOReturn
-IOMemoryMapTracking(IOTrackingUser * tracking, task_t * task,
-    mach_vm_address_t * address, mach_vm_size_t * size)
-{
-#define iomap_offsetof(type, field) ((size_t)(&((type *)NULL)->field))
-
-	IOMemoryMap * map = (typeof(map))(((uintptr_t) tracking) - iomap_offsetof(IOMemoryMap, fTracking));
-
-	if (!map->fAddressMap || (map->fAddressMap != get_task_map(map->fAddressTask))) {
-		return kIOReturnNotReady;
-	}
-
-	*task    = map->fAddressTask;
-	*address = map->fAddress;
-	*size    = map->fLength;
-
-	return kIOReturnSuccess;
-}
-#endif /* IOTRACKING */
-
-IOReturn
-IOGeneralMemoryDescriptor::doUnmap(
-	vm_map_t                addressMap,
-	IOVirtualAddress        __address,
-	IOByteCount             __length )
-{
-	IOTimeStampIntervalConstantFiltered traceInterval(IODBG_MDESC(IOMDESC_UNMAP), VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(__address), __length);
-	IOReturn ret;
-	ret = super::doUnmap(addressMap, __address, __length);
-	traceInterval.setEndArg1(ret);
-	return ret;
-}
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-#undef super
-#define super OSObject
-
-OSDefineMetaClassAndStructorsWithZone( IOMemoryMap, OSObject, ZC_NONE )
-
-OSMetaClassDefineReservedUnused(IOMemoryMap, 0);
-OSMetaClassDefineReservedUnused(IOMemoryMap, 1);
-OSMetaClassDefineReservedUnused(IOMemoryMap, 2);
-OSMetaClassDefineReservedUnused(IOMemoryMap, 3);
-OSMetaClassDefineReservedUnused(IOMemoryMap, 4);
-OSMetaClassDefineReservedUnused(IOMemoryMap, 5);
-OSMetaClassDefineReservedUnused(IOMemoryMap, 6);
-OSMetaClassDefineReservedUnused(IOMemoryMap, 7);
-
-/* ex-inline function implementation */
-IOPhysicalAddress
-IOMemoryMap::getPhysicalAddress()
-{
-	return getPhysicalSegment( 0, NULL );
-}
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-bool
-IOMemoryMap::init(
-	task_t                  intoTask,
-	mach_vm_address_t       toAddress,
-	IOOptionBits            _options,
-	mach_vm_size_t          _offset,
-	mach_vm_size_t          _length )
-{
-	if (!intoTask) {
-		return false;
-	}
-
-	if (!super::init()) {
-		return false;
-	}
-
-	fAddressMap  = get_task_map(intoTask);
-	if (!fAddressMap) {
-		return false;
-	}
-	vm_map_reference(fAddressMap);
-
-	fAddressTask = intoTask;
-	fOptions     = _options;
-	fLength      = _length;
-	fOffset      = _offset;
-	fAddress     = toAddress;
-
-	return true;
-}
-
-bool
-IOMemoryMap::setMemoryDescriptor(IOMemoryDescriptor * _memory, mach_vm_size_t _offset)
-{
-	if (!_memory) {
-		return false;
-	}
-
-	if (!fSuperMap) {
-		if ((_offset + fLength) > _memory->getLength()) {
-			return false;
-		}
-		fOffset = _offset;
-	}
-
-
-	OSSharedPtr<IOMemoryDescriptor> tempval(_memory, OSRetain);
-	if (fMemory) {
-		if (fMemory != _memory) {
-			fMemory->removeMapping(this);
-		}
-	}
-	fMemory = os::move(tempval);
-
-	return true;
-}
-
-IOReturn
-IOMemoryDescriptor::doMap(
-	vm_map_t                __addressMap,
-	IOVirtualAddress *      __address,
-	IOOptionBits            options,
-	IOByteCount             __offset,
-	IOByteCount             __length )
-{
-	return kIOReturnUnsupported;
-}
-
-IOReturn
-IOMemoryDescriptor::handleFault(
-	void *                  _pager,
-	mach_vm_size_t          sourceOffset,
-	mach_vm_size_t          length)
-{
-	if (kIOMemoryRedirected & _flags) {
-#if DEBUG
-		IOLog("sleep mem redirect %p, %qx\n", this, sourceOffset);
+    } while( false );
+
+    if (!doRedirect)
+    {
+        WAKEUP;
+    }
+
+    UNLOCK;
+
+    // temporary binary compatibility
+    IOSubMemoryDescriptor * subMem;
+    if( (subMem = OSDynamicCast( IOSubMemoryDescriptor, this)))
+	err = subMem->redirect( safeTask, doRedirect );
+    else
+	err = kIOReturnSuccess;
+
+    return( err );
+}
+
+IOReturn IOSubMemoryDescriptor::redirect( task_t safeTask, bool doRedirect )
+{
+    return( _parent->redirect( safeTask, doRedirect ));
+}
+
+IOReturn _IOMemoryMap::redirect( task_t safeTask, bool doRedirect )
+{
+    IOReturn err = kIOReturnSuccess;
+
+    if( superMap) {
+//        err = ((_IOMemoryMap *)superMap)->redirect( safeTask, doRedirect );
+    } else {
+
+        LOCK;
+        if( logical && addressMap
+	&& (!safeTask || (get_task_map(safeTask) != addressMap))
+        && (0 == (options & kIOMapStatic)))
+	{
+	    IOUnmapPages( addressMap, logical, length );
+            if(!doRedirect && safeTask
+	     && ((memory->_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical))
+	     {
+                err = vm_deallocate( addressMap, logical, length );
+                err = memory->doMap( addressMap, &logical,
+                                     (options & ~kIOMapAnywhere) /*| kIOMapReserve*/,
+                                     offset, length );
+            } else
+                err = kIOReturnSuccess;
+#ifdef DEBUG
+	    IOLog("IOMemoryMap::redirect(%d, %p) %x:%lx from %p\n", doRedirect, this, logical, length, addressMap);
 #endif
-		do {
-			SLEEP;
-		} while (kIOMemoryRedirected & _flags);
-	}
-	return kIOReturnSuccess;
-}
-
-IOReturn
-IOMemoryDescriptor::populateDevicePager(
-	void *                  _pager,
-	vm_map_t                addressMap,
-	mach_vm_address_t       address,
-	mach_vm_size_t          sourceOffset,
-	mach_vm_size_t          length,
-	IOOptionBits            options )
-{
-	IOReturn            err = kIOReturnSuccess;
-	memory_object_t     pager = (memory_object_t) _pager;
-	mach_vm_size_t      size;
-	mach_vm_size_t      bytes;
-	mach_vm_size_t      page;
-	mach_vm_size_t      pageOffset;
-	mach_vm_size_t      pagerOffset;
-	IOPhysicalLength    segLen, chunk;
-	addr64_t            physAddr;
-	IOOptionBits        type;
-
-	type = _flags & kIOMemoryTypeMask;
-
-	if (reserved->dp.pagerContig) {
-		sourceOffset = 0;
-		pagerOffset  = 0;
-	}
-
-	physAddr = getPhysicalSegment( sourceOffset, &segLen, kIOMemoryMapperNone );
-	assert( physAddr );
-	pageOffset = physAddr - trunc_page_64( physAddr );
-	pagerOffset = sourceOffset;
-
-	size = length + pageOffset;
-	physAddr -= pageOffset;
-
-	segLen += pageOffset;
-	bytes = size;
-	do{
-		// in the middle of the loop only map whole pages
-		if (segLen >= bytes) {
-			segLen = bytes;
-		} else if (segLen != trunc_page_64(segLen)) {
-			err = kIOReturnVMError;
-		}
-		if (physAddr != trunc_page_64(physAddr)) {
-			err = kIOReturnBadArgument;
-		}
-
-		if (kIOReturnSuccess != err) {
-			break;
-		}
-
-#if DEBUG || DEVELOPMENT
-		if ((kIOMemoryTypeUPL != type)
-		    && pmap_has_managed_page((ppnum_t) atop_64(physAddr), (ppnum_t) atop_64(physAddr + segLen - 1))) {
-			OSReportWithBacktrace("IOMemoryDescriptor physical with managed page 0x%qx:0x%qx",
-			    physAddr, (uint64_t)segLen);
-		}
-#endif /* DEBUG || DEVELOPMENT */
-
-		chunk = (reserved->dp.pagerContig ? round_page(segLen) : page_size);
-		for (page = 0;
-		    (page < segLen) && (KERN_SUCCESS == err);
-		    page += chunk) {
-			err = device_pager_populate_object(pager, pagerOffset,
-			    (ppnum_t)(atop_64(physAddr + page)), chunk);
-			pagerOffset += chunk;
-		}
-
-		assert(KERN_SUCCESS == err);
-		if (err) {
-			break;
-		}
-
-		// This call to vm_fault causes an early pmap level resolution
-		// of the mappings created above for kernel mappings, since
-		// faulting in later can't take place from interrupt level.
-		if ((addressMap == kernel_map) && !(kIOMemoryRedirected & _flags)) {
-			err = vm_fault(addressMap,
-			    (vm_map_offset_t)trunc_page_64(address),
-			    options & kIOMapReadOnly ? VM_PROT_READ : VM_PROT_READ | VM_PROT_WRITE,
-			    FALSE, VM_KERN_MEMORY_NONE,
-			    THREAD_UNINT, NULL,
-			    (vm_map_offset_t)0);
-
-			if (KERN_SUCCESS != err) {
-				break;
-			}
-		}
-
-		sourceOffset += segLen - pageOffset;
-		address += segLen;
-		bytes -= segLen;
-		pageOffset = 0;
-	}while (bytes && (physAddr = getPhysicalSegment( sourceOffset, &segLen, kIOMemoryMapperNone )));
-
-	if (bytes) {
-		err = kIOReturnBadArgument;
-	}
-
-	return err;
-}
-
-IOReturn
-IOMemoryDescriptor::doUnmap(
-	vm_map_t                addressMap,
-	IOVirtualAddress        __address,
-	IOByteCount             __length )
-{
-	IOReturn          err;
-	IOMemoryMap *     mapping;
-	mach_vm_address_t address;
-	mach_vm_size_t    length;
-
-	if (__length) {
-		panic("doUnmap");
-	}
-
-	mapping = (IOMemoryMap *) __address;
-	addressMap = mapping->fAddressMap;
-	address    = mapping->fAddress;
-	length     = mapping->fLength;
-
-	if (kIOMapOverwrite & mapping->fOptions) {
-		err = KERN_SUCCESS;
-	} else {
-		if ((addressMap == kernel_map) && (kIOMemoryBufferPageable & _flags)) {
-			addressMap = IOPageableMapForAddress( address );
-		}
-#if DEBUG
-		if (kIOLogMapping & gIOKitDebug) {
-			IOLog("IOMemoryDescriptor::doUnmap map %p, 0x%qx:0x%qx\n",
-			    addressMap, address, length );
-		}
-#endif
-		err = IOMemoryDescriptorMapDealloc(mapping->fOptions, addressMap, address, length );
-		if (vm_map_page_mask(addressMap) < PAGE_MASK) {
-			DEBUG4K_IOKIT("map %p address 0x%llx length 0x%llx err 0x%x\n", addressMap, address, length, err);
-		}
-	}
-
-#if IOTRACKING
-	IOTrackingRemoveUser(gIOMapTracking, &mapping->fTracking);
-#endif /* IOTRACKING */
-
-	return err;
-}
-
-IOReturn
-IOMemoryDescriptor::redirect( task_t safeTask, bool doRedirect )
-{
-	IOReturn            err = kIOReturnSuccess;
-	IOMemoryMap *       mapping = NULL;
-	OSSharedPtr<OSIterator>        iter;
-
-	LOCK;
-
-	if (doRedirect) {
-		_flags |= kIOMemoryRedirected;
-	} else {
-		_flags &= ~kIOMemoryRedirected;
-	}
-
-	do {
-		if ((iter = OSCollectionIterator::withCollection( _mappings.get()))) {
-			memory_object_t   pager;
-
-			if (reserved) {
-				pager = (memory_object_t) reserved->dp.devicePager;
-			} else {
-				pager = MACH_PORT_NULL;
-			}
-
-			while ((mapping = (IOMemoryMap *) iter->getNextObject())) {
-				mapping->redirect( safeTask, doRedirect );
-				if (!doRedirect && !safeTask && pager && (kernel_map == mapping->fAddressMap)) {
-					err = populateDevicePager(pager, mapping->fAddressMap, mapping->fAddress, mapping->fOffset, mapping->fLength, kIOMapDefaultCache );
-				}
-			}
-
-			iter.reset();
-		}
-	} while (false);
-
-	if (!doRedirect) {
-		WAKEUP;
-	}
-
-	UNLOCK;
-
-#ifndef __LP64__
-	// temporary binary compatibility
-	IOSubMemoryDescriptor * subMem;
-	if ((subMem = OSDynamicCast( IOSubMemoryDescriptor, this))) {
-		err = subMem->redirect( safeTask, doRedirect );
-	} else {
-		err = kIOReturnSuccess;
-	}
-#endif /* !__LP64__ */
-
-	return err;
-}
-
-IOReturn
-IOMemoryMap::redirect( task_t safeTask, bool doRedirect )
-{
-	IOReturn err = kIOReturnSuccess;
-
-	if (fSuperMap) {
-//        err = ((IOMemoryMap *)superMap)->redirect( safeTask, doRedirect );
-	} else {
-		LOCK;
-
-		do{
-			if (!fAddress) {
-				break;
-			}
-			if (!fAddressMap) {
-				break;
-			}
-
-			if ((!safeTask || (get_task_map(safeTask) != fAddressMap))
-			    && (0 == (fOptions & kIOMapStatic))) {
-				IOUnmapPages( fAddressMap, fAddress, fLength );
-				err = kIOReturnSuccess;
-#if DEBUG
-				IOLog("IOMemoryMap::redirect(%d, %p) 0x%qx:0x%qx from %p\n", doRedirect, this, fAddress, fLength, fAddressMap);
-#endif
-			} else if (kIOMapWriteCombineCache == (fOptions & kIOMapCacheMask)) {
-				IOOptionBits newMode;
-				newMode = (fOptions & ~kIOMapCacheMask) | (doRedirect ? kIOMapInhibitCache : kIOMapWriteCombineCache);
-				IOProtectCacheMode(fAddressMap, fAddress, fLength, newMode);
-			}
-		}while (false);
-		UNLOCK;
-	}
-
-	if ((((fMemory->_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical)
-	    || ((fMemory->_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical64))
-	    && safeTask
-	    && (doRedirect != (0 != (fMemory->_flags & kIOMemoryRedirected)))) {
-		fMemory->redirect(safeTask, doRedirect);
-	}
-
-	return err;
-}
-
-IOReturn
-IOMemoryMap::unmap( void )
-{
-	IOReturn    err;
-
-	LOCK;
-
-	if (fAddress && fAddressMap && (NULL == fSuperMap) && fMemory
-	    && (0 == (kIOMapStatic & fOptions))) {
-		err = fMemory->doUnmap(fAddressMap, (IOVirtualAddress) this, 0);
-	} else {
-		err = kIOReturnSuccess;
-	}
-
-	if (fAddressMap) {
-		vm_map_deallocate(fAddressMap);
-		fAddressMap = NULL;
-	}
-
-	fAddress = 0;
-
-	UNLOCK;
-
-	return err;
-}
-
-void
-IOMemoryMap::taskDied( void )
-{
-	LOCK;
-	if (fUserClientUnmap) {
-		unmap();
-	}
-#if IOTRACKING
-	else {
-		IOTrackingRemoveUser(gIOMapTracking, &fTracking);
-	}
-#endif /* IOTRACKING */
-
-	if (fAddressMap) {
-		vm_map_deallocate(fAddressMap);
-		fAddressMap = NULL;
-	}
-	fAddressTask = NULL;
-	fAddress     = 0;
-	UNLOCK;
-}
-
-IOReturn
-IOMemoryMap::userClientUnmap( void )
-{
-	fUserClientUnmap = true;
-	return kIOReturnSuccess;
+        }
+        UNLOCK;
+    }
+
+    if (((memory->_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical) 
+     && safeTask
+     && (doRedirect != (0 != (memory->_flags & kIOMemoryRedirected))))
+	memory->redirect(safeTask, doRedirect);
+
+    return( err );
+}
+
+IOReturn _IOMemoryMap::unmap( void )
+{
+    IOReturn	err;
+
+    LOCK;
+
+    if( logical && addressMap && (0 == superMap)
+	&& (0 == (options & kIOMapStatic))) {
+
+        err = memory->doUnmap( addressMap, logical, length );
+        vm_map_deallocate(addressMap);
+        addressMap = 0;
+
+    } else
+	err = kIOReturnSuccess;
+
+    logical = 0;
+
+    UNLOCK;
+
+    return( err );
+}
+
+void _IOMemoryMap::taskDied( void )
+{
+    LOCK;
+    if( addressMap) {
+        vm_map_deallocate(addressMap);
+        addressMap = 0;
+    }
+    addressTask	= 0;
+    logical	= 0;
+    UNLOCK;
 }
 
 // Overload the release mechanism.  All mappings must be a member
 // of a memory descriptors _mappings set.  This means that we
 // always have 2 references on a mapping.  When either of these mappings
 // are released we need to free ourselves.
-void
-IOMemoryMap::taggedRelease(const void *tag) const
-{
-	super::taggedRelease(tag, 2);
-}
-
-void
-IOMemoryMap::free()
-{
-	unmap();
-
-	if (fMemory) {
-		LOCK;
-		fMemory->removeMapping(this);
-		UNLOCK;
-		fMemory.reset();
-	}
-
-	if (fSuperMap) {
-		fSuperMap.reset();
-	}
-
-	if (fRedirUPL) {
-		upl_commit(fRedirUPL, NULL, 0);
-		upl_deallocate(fRedirUPL);
-	}
-
-	super::free();
-}
-
-IOByteCount
-IOMemoryMap::getLength()
-{
-	return fLength;
-}
-
-IOVirtualAddress
-IOMemoryMap::getVirtualAddress()
-{
-#ifndef __LP64__
-	if (fSuperMap) {
-		fSuperMap->getVirtualAddress();
-	} else if (fAddressMap
-	    && vm_map_is_64bit(fAddressMap)
-	    && (sizeof(IOVirtualAddress) < 8)) {
-		OSReportWithBacktrace("IOMemoryMap::getVirtualAddress(0x%qx) called on 64b map; use ::getAddress()", fAddress);
-	}
-#endif /* !__LP64__ */
-
-	return fAddress;
-}
-
-#ifndef __LP64__
-mach_vm_address_t
-IOMemoryMap::getAddress()
-{
-	return fAddress;
-}
-
-mach_vm_size_t
-IOMemoryMap::getSize()
-{
-	return fLength;
-}
-#endif /* !__LP64__ */
-
-
-task_t
-IOMemoryMap::getAddressTask()
-{
-	if (fSuperMap) {
-		return fSuperMap->getAddressTask();
-	} else {
-		return fAddressTask;
-	}
-}
-
-IOOptionBits
-IOMemoryMap::getMapOptions()
-{
-	return fOptions;
-}
-
-IOMemoryDescriptor *
-IOMemoryMap::getMemoryDescriptor()
-{
-	return fMemory.get();
-}
-
-IOMemoryMap *
-IOMemoryMap::copyCompatible(
-	IOMemoryMap * newMapping )
-{
-	task_t              task      = newMapping->getAddressTask();
-	mach_vm_address_t   toAddress = newMapping->fAddress;
-	IOOptionBits        _options  = newMapping->fOptions;
-	mach_vm_size_t      _offset   = newMapping->fOffset;
-	mach_vm_size_t      _length   = newMapping->fLength;
-
-	if ((!task) || (!fAddressMap) || (fAddressMap != get_task_map(task))) {
-		return NULL;
-	}
-	if ((fOptions ^ _options) & kIOMapReadOnly) {
-		return NULL;
-	}
-	if ((fOptions ^ _options) & kIOMapGuardedMask) {
-		return NULL;
-	}
-	if ((kIOMapDefaultCache != (_options & kIOMapCacheMask))
-	    && ((fOptions ^ _options) & kIOMapCacheMask)) {
-		return NULL;
-	}
-
-	if ((0 == (_options & kIOMapAnywhere)) && (fAddress != toAddress)) {
-		return NULL;
-	}
-
-	if (_offset < fOffset) {
-		return NULL;
-	}
-
-	_offset -= fOffset;
-
-	if ((_offset + _length) > fLength) {
-		return NULL;
-	}
-
-	if (!taggedTryRetain(NULL)) {
-		return NULL;
-	}
-
-	if ((fLength == _length) && !_offset) {
-		newMapping = this;
-	} else {
-		newMapping->fSuperMap.reset(this, OSNoRetain);
-		newMapping->fOffset   = fOffset + _offset;
-		newMapping->fAddress  = fAddress + _offset;
-	}
-
-	return newMapping;
-}
-
-IOReturn
-IOMemoryMap::wireRange(
-	uint32_t                options,
-	mach_vm_size_t          offset,
-	mach_vm_size_t          length)
-{
-	IOReturn kr;
-	mach_vm_address_t start = trunc_page_64(fAddress + offset);
-	mach_vm_address_t end   = round_page_64(fAddress + offset + length);
-	vm_prot_t prot;
-
-	prot = (kIODirectionOutIn & options);
-	if (prot) {
-		kr = vm_map_wire_kernel(fAddressMap, start, end, prot, (vm_tag_t) fMemory->getVMTag(kernel_map), FALSE);
-	} else {
-		kr = vm_map_unwire(fAddressMap, start, end, FALSE);
-	}
-
-	return kr;
-}
-
-
-IOPhysicalAddress
-#ifdef __LP64__
-IOMemoryMap::getPhysicalSegment( IOByteCount _offset, IOPhysicalLength * _length, IOOptionBits _options)
-#else /* !__LP64__ */
-IOMemoryMap::getPhysicalSegment( IOByteCount _offset, IOPhysicalLength * _length)
-#endif /* !__LP64__ */
-{
-	IOPhysicalAddress   address;
-
-	LOCK;
-#ifdef __LP64__
-	address = fMemory->getPhysicalSegment( fOffset + _offset, _length, _options );
-#else /* !__LP64__ */
-	address = fMemory->getPhysicalSegment( fOffset + _offset, _length );
-#endif /* !__LP64__ */
+void _IOMemoryMap::taggedRelease(const void *tag) const
+{
+    LOCK;
+    super::taggedRelease(tag, 2);
+    UNLOCK;
+}
+
+void _IOMemoryMap::free()
+{
+    unmap();
+
+    if( memory) {
+        LOCK;
+	memory->removeMapping( this);
 	UNLOCK;
-
-	return address;
+	memory->release();
+    }
+
+    if (owner && (owner != memory))
+    {
+        LOCK;
+	owner->removeMapping(this);
+	UNLOCK;
+    }
+
+    if( superMap)
+	superMap->release();
+
+    if (redirUPL) {
+	upl_commit(redirUPL, NULL, 0);
+	upl_deallocate(redirUPL);
+    }
+
+    super::free();
+}
+
+IOByteCount _IOMemoryMap::getLength()
+{
+    return( length );
+}
+
+IOVirtualAddress _IOMemoryMap::getVirtualAddress()
+{
+    return( logical);
+}
+
+task_t _IOMemoryMap::getAddressTask()
+{
+    if( superMap)
+	return( superMap->getAddressTask());
+    else
+        return( addressTask);
+}
+
+IOOptionBits _IOMemoryMap::getMapOptions()
+{
+    return( options);
+}
+
+IOMemoryDescriptor * _IOMemoryMap::getMemoryDescriptor()
+{
+    return( memory );
+}
+
+_IOMemoryMap * _IOMemoryMap::copyCompatible(
+		IOMemoryDescriptor *	owner,
+                task_t			task,
+                IOVirtualAddress	toAddress,
+                IOOptionBits		_options,
+                IOByteCount		_offset,
+                IOByteCount		_length )
+{
+    _IOMemoryMap * mapping;
+
+    if( (!task) || (!addressMap) || (addressMap != get_task_map(task)))
+	return( 0 );
+    if( options & kIOMapUnique)
+	return( 0 );
+    if( (options ^ _options) & kIOMapReadOnly)
+	return( 0 );
+    if( (kIOMapDefaultCache != (_options & kIOMapCacheMask)) 
+     && ((options ^ _options) & kIOMapCacheMask))
+	return( 0 );
+
+    if( (0 == (_options & kIOMapAnywhere)) && (logical != toAddress))
+	return( 0 );
+
+    if( _offset < offset)
+	return( 0 );
+
+    _offset -= offset;
+
+    if( (_offset + _length) > length)
+	return( 0 );
+
+    if( (length == _length) && (!_offset)) {
+        retain();
+	mapping = this;
+
+    } else {
+        mapping = new _IOMemoryMap;
+        if( mapping
+        && !mapping->initCompatible( owner, this, _offset, _length )) {
+            mapping->release();
+            mapping = 0;
+        }
+    }
+
+    return( mapping );
+}
+
+IOPhysicalAddress _IOMemoryMap::getPhysicalSegment( IOByteCount _offset,
+	       					    IOPhysicalLength * _length)
+{
+    IOPhysicalAddress	address;
+
+    LOCK;
+    address = memory->getPhysicalSegment( offset + _offset, _length );
+    UNLOCK;
+
+    return( address );
 }
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
@@ -6049,474 +2611,726 @@
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-void
-IOMemoryDescriptor::initialize( void )
-{
-	if (NULL == gIOMemoryLock) {
-		gIOMemoryLock = IORecursiveLockAlloc();
+void IOMemoryDescriptor::initialize( void )
+{
+    if( 0 == gIOMemoryLock)
+	gIOMemoryLock = IORecursiveLockAlloc();
+
+    IORegistryEntry::getRegistryRoot()->setProperty(kIOMaximumMappedIOByteCountKey,
+						    ptoa_64(gIOMaximumMappedIOPageCount), 64);
+}
+
+void IOMemoryDescriptor::free( void )
+{
+    if( _mappings)
+	_mappings->release();
+
+    super::free();
+}
+
+IOMemoryMap * IOMemoryDescriptor::setMapping(
+	task_t			intoTask,
+	IOVirtualAddress	mapAddress,
+	IOOptionBits		options )
+{
+    _IOMemoryMap *		newMap;
+
+    newMap = new _IOMemoryMap;
+
+    LOCK;
+
+    if( newMap
+     && !newMap->initWithDescriptor( this, intoTask, mapAddress,
+                    options | kIOMapStatic, 0, getLength() )) {
+	newMap->release();
+	newMap = 0;
+    }
+
+    addMapping( newMap);
+
+    UNLOCK;
+
+    return( newMap);
+}
+
+IOMemoryMap * IOMemoryDescriptor::map( 
+	IOOptionBits		options )
+{
+
+    return( makeMapping( this, kernel_task, 0,
+			options | kIOMapAnywhere,
+			0, getLength() ));
+}
+
+IOMemoryMap * IOMemoryDescriptor::map(
+	task_t			intoTask,
+	IOVirtualAddress	toAddress,
+	IOOptionBits		options,
+	IOByteCount		offset,
+	IOByteCount		length )
+{
+    if( 0 == length)
+	length = getLength();
+
+    return( makeMapping( this, intoTask, toAddress, options, offset, length ));
+}
+
+IOReturn _IOMemoryMap::redirect(IOMemoryDescriptor * newBackingMemory,
+			        IOOptionBits         options,
+			        IOByteCount          offset)
+{
+    IOReturn err = kIOReturnSuccess;
+    IOMemoryDescriptor * physMem = 0;
+
+    LOCK;
+
+    if (logical && addressMap) do 
+    {
+	if ((memory->_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical)
+	{
+	    physMem = memory;
+	    physMem->retain();
 	}
 
-	gIOLastPage = IOGetLastPageNumber();
-}
-
-void
-IOMemoryDescriptor::free( void )
-{
-	if (_mappings) {
-		_mappings.reset();
+	if (!redirUPL)
+	{
+	    vm_size_t size = length;
+	    int flags = UPL_COPYOUT_FROM | UPL_SET_INTERNAL 
+			| UPL_SET_LITE | UPL_SET_IO_WIRE | UPL_BLOCK_ACCESS;
+	    if (KERN_SUCCESS != memory_object_iopl_request((ipc_port_t) memory->_memEntry, 0, &size, &redirUPL,
+					    NULL, NULL,
+					    &flags))
+		redirUPL = 0;
+
+	    if (physMem)
+	    {
+		IOUnmapPages( addressMap, logical, length );
+		physMem->redirect(0, true);
+	    }
 	}
 
-	if (reserved) {
-		cleanKernelReserved(reserved);
-		IOFreeType(reserved, IOMemoryDescriptorReserved);
-		reserved = NULL;
+	if (newBackingMemory)
+	{
+	    if (newBackingMemory != memory)
+	    {
+		if (this != newBackingMemory->makeMapping(newBackingMemory, addressTask, (IOVirtualAddress) this, 
+							    options | kIOMapUnique | kIOMapReference,
+							    offset, length))
+		    err = kIOReturnError;
+	    }
+	    if (redirUPL)
+	    {
+		upl_commit(redirUPL, NULL, 0);
+		upl_deallocate(redirUPL);
+		redirUPL = 0;
+	    }
+	    if (physMem)
+		physMem->redirect(0, false);
 	}
-	super::free();
-}
-
-OSSharedPtr<IOMemoryMap>
-IOMemoryDescriptor::setMapping(
-	task_t                  intoTask,
-	IOVirtualAddress        mapAddress,
-	IOOptionBits            options )
-{
-	return createMappingInTask( intoTask, mapAddress,
-	           options | kIOMapStatic,
-	           0, getLength());
-}
-
-OSSharedPtr<IOMemoryMap>
-IOMemoryDescriptor::map(
-	IOOptionBits            options )
-{
-	return createMappingInTask( kernel_task, 0,
-	           options | kIOMapAnywhere,
-	           0, getLength());
-}
-
-#ifndef __LP64__
-OSSharedPtr<IOMemoryMap>
-IOMemoryDescriptor::map(
-	task_t                  intoTask,
-	IOVirtualAddress        atAddress,
-	IOOptionBits            options,
-	IOByteCount             offset,
-	IOByteCount             length )
-{
-	if ((!(kIOMapAnywhere & options)) && vm_map_is_64bit(get_task_map(intoTask))) {
-		OSReportWithBacktrace("IOMemoryDescriptor::map() in 64b task, use ::createMappingInTask()");
-		return NULL;
+    }
+    while (false);
+
+    UNLOCK;
+
+    if (physMem)
+	physMem->release();
+
+    return (err);
+}
+
+IOMemoryMap * IOMemoryDescriptor::makeMapping(
+	IOMemoryDescriptor *	owner,
+	task_t			intoTask,
+	IOVirtualAddress	toAddress,
+	IOOptionBits		options,
+	IOByteCount		offset,
+	IOByteCount		length )
+{
+    IOMemoryDescriptor * mapDesc = 0;
+    _IOMemoryMap *	mapping = 0;
+    OSIterator *	iter;
+
+    LOCK;
+
+    do
+    {
+	if (kIOMapUnique & options)
+	{
+	    IOPhysicalAddress phys;
+	    IOByteCount       physLen;
+
+	    if (owner != this)
+		continue;
+
+	    if ((_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical)
+	    {
+		phys = getPhysicalSegment(offset, &physLen);
+		if (!phys || (physLen < length))
+		    continue;
+    
+		mapDesc = IOMemoryDescriptor::withPhysicalAddress(
+				phys, length, _direction);
+		if (!mapDesc)
+		    continue;
+		offset = 0;
+	    }
+	    else
+	    {
+		mapDesc = this;
+		mapDesc->retain();
+	    }
+
+	    if (kIOMapReference & options)
+	    {
+		mapping = (_IOMemoryMap *) toAddress;
+		mapping->retain();
+
+#if 1
+		uint32_t pageOffset1 = mapDesc->getSourceSegment( offset, NULL );
+		pageOffset1 -= trunc_page_32( pageOffset1 );
+
+		uint32_t pageOffset2 = mapping->getVirtualAddress();
+		pageOffset2 -= trunc_page_32( pageOffset2 );
+		
+		if (pageOffset1 != pageOffset2)
+		    IOLog("::redirect can't map offset %x to addr %x\n", 
+			    pageOffset1, mapping->getVirtualAddress());
+#endif
+
+
+		if (!mapping->initWithDescriptor( mapDesc, intoTask, toAddress, options,
+						    offset, length ))
+		{
+#ifdef DEBUG
+		    IOLog("Didn't redirect map %08lx : %08lx\n", offset, length );
+#endif
+		}
+
+		if (mapping->owner)
+		    mapping->owner->removeMapping(mapping);
+		continue;
+	    }
 	}
-
-	return createMappingInTask(intoTask, atAddress,
-	           options, offset, length);
-}
-#endif /* !__LP64__ */
-
-OSSharedPtr<IOMemoryMap>
-IOMemoryDescriptor::createMappingInTask(
-	task_t                  intoTask,
-	mach_vm_address_t       atAddress,
-	IOOptionBits            options,
-	mach_vm_size_t          offset,
-	mach_vm_size_t          length)
-{
-	IOMemoryMap * result;
-	IOMemoryMap * mapping;
-
-	if (0 == length) {
-		length = getLength();
+	else
+	{
+	    // look for an existing mapping
+	    if( (iter = OSCollectionIterator::withCollection( _mappings))) {
+    
+		while( (mapping = (_IOMemoryMap *) iter->getNextObject())) {
+    
+		    if( (mapping = mapping->copyCompatible( 
+					    owner, intoTask, toAddress,
+					    options | kIOMapReference,
+					    offset, length )))
+			break;
+		}
+		iter->release();
+	    }
+
+
+	if (mapping)
+	    mapping->retain();
+
+	    if( mapping || (options & kIOMapReference))
+		continue;
+
+	    mapDesc = owner;
+	    mapDesc->retain();
 	}
-
-	mapping = new IOMemoryMap;
-
-	if (mapping
-	    && !mapping->init( intoTask, atAddress,
-	    options, offset, length )) {
-		mapping->release();
-		mapping = NULL;
+	owner = this;
+
+        mapping = new _IOMemoryMap;
+	if( mapping
+	&& !mapping->initWithDescriptor( mapDesc, intoTask, toAddress, options,
+			   offset, length )) {
+#ifdef DEBUG
+	    IOLog("Didn't make map %08lx : %08lx\n", offset, length );
+#endif
+	    mapping->release();
+            mapping = 0;
 	}
 
-	if (mapping) {
-		result = makeMapping(this, intoTask, (IOVirtualAddress) mapping, options | kIOMap64Bit, 0, 0);
-	} else {
-		result = nullptr;
+	if (mapping)
+	    mapping->retain();
+
+    } while( false );
+
+    if (mapping)
+    {
+	mapping->owner = owner;
+	owner->addMapping( mapping);
+	mapping->release();
+    }
+
+    UNLOCK;
+
+    if (mapDesc)
+	mapDesc->release();
+
+    return( mapping);
+}
+
+void IOMemoryDescriptor::addMapping(
+	IOMemoryMap * mapping )
+{
+    if( mapping) {
+        if( 0 == _mappings)
+            _mappings = OSSet::withCapacity(1);
+	if( _mappings )
+	    _mappings->setObject( mapping );
+    }
+}
+
+void IOMemoryDescriptor::removeMapping(
+	IOMemoryMap * mapping )
+{
+    if( _mappings)
+        _mappings->removeObject( mapping);
+}
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+#undef super
+#define super IOMemoryDescriptor
+
+OSDefineMetaClassAndStructors(IOSubMemoryDescriptor, IOMemoryDescriptor)
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+bool IOSubMemoryDescriptor::initSubRange( IOMemoryDescriptor * parent,
+					IOByteCount offset, IOByteCount length,
+					IODirection direction )
+{
+    if( !parent)
+	return( false);
+
+    if( (offset + length) > parent->getLength())
+	return( false);
+
+    /*
+     * We can check the _parent instance variable before having ever set it
+     * to an initial value because I/O Kit guarantees that all our instance
+     * variables are zeroed on an object's allocation.
+     */
+
+    if( !_parent) {
+	if( !super::init())
+	    return( false );
+    } else {
+	/*
+	 * An existing memory descriptor is being retargeted to
+	 * point to somewhere else.  Clean up our present state.
+	 */
+
+	_parent->release();
+	_parent = 0;
+    }
+
+    parent->retain();
+    _parent	= parent;
+    _start	= offset;
+    _length	= length;
+    _direction  = direction;
+    _tag	= parent->getTag();
+
+    return( true );
+}
+
+void IOSubMemoryDescriptor::free( void )
+{
+    if( _parent)
+	_parent->release();
+
+    super::free();
+}
+
+
+IOPhysicalAddress IOSubMemoryDescriptor::getPhysicalSegment( IOByteCount offset,
+						      	IOByteCount * length )
+{
+    IOPhysicalAddress	address;
+    IOByteCount		actualLength;
+
+    assert(offset <= _length);
+
+    if( length)
+        *length = 0;
+
+    if( offset >= _length)
+        return( 0 );
+
+    address = _parent->getPhysicalSegment( offset + _start, &actualLength );
+
+    if( address && length)
+	*length = min( _length - offset, actualLength );
+
+    return( address );
+}
+
+
+IOReturn IOSubMemoryDescriptor::doMap(
+	vm_map_t		addressMap,
+	IOVirtualAddress *	atAddress,
+	IOOptionBits		options,
+	IOByteCount		sourceOffset,
+	IOByteCount		length )
+{
+    if( sourceOffset >= _length)
+        return( kIOReturnOverrun );
+    return (_parent->doMap(addressMap, atAddress, options, sourceOffset + _start, length));
+}
+
+IOPhysicalAddress IOSubMemoryDescriptor::getSourceSegment( IOByteCount offset,
+						      	   IOByteCount * length )
+{
+    IOPhysicalAddress	address;
+    IOByteCount		actualLength;
+
+    assert(offset <= _length);
+
+    if( length)
+        *length = 0;
+
+    if( offset >= _length)
+        return( 0 );
+
+    address = _parent->getSourceSegment( offset + _start, &actualLength );
+
+    if( address && length)
+	*length = min( _length - offset, actualLength );
+
+    return( address );
+}
+
+void * IOSubMemoryDescriptor::getVirtualSegment(IOByteCount offset,
+					IOByteCount * lengthOfSegment)
+{
+    return( 0 );
+}
+
+IOByteCount IOSubMemoryDescriptor::readBytes(IOByteCount offset,
+					void * bytes, IOByteCount length)
+{
+    IOByteCount	byteCount;
+
+    assert(offset <= _length);
+
+    if( offset >= _length)
+        return( 0 );
+
+    LOCK;
+    byteCount = _parent->readBytes( _start + offset, bytes,
+				min(length, _length - offset) );
+    UNLOCK;
+
+    return( byteCount );
+}
+
+IOByteCount IOSubMemoryDescriptor::writeBytes(IOByteCount offset,
+				const void* bytes, IOByteCount length)
+{
+    IOByteCount	byteCount;
+
+    assert(offset <= _length);
+
+    if( offset >= _length)
+        return( 0 );
+
+    LOCK;
+    byteCount = _parent->writeBytes( _start + offset, bytes,
+				min(length, _length - offset) );
+    UNLOCK;
+
+    return( byteCount );
+}
+
+IOReturn IOSubMemoryDescriptor::setPurgeable( IOOptionBits newState,
+                                    IOOptionBits * oldState )
+{
+    IOReturn err;
+
+    LOCK;
+    err = _parent->setPurgeable( newState, oldState );
+    UNLOCK;
+
+    return( err );
+}
+
+IOReturn IOSubMemoryDescriptor::performOperation( IOOptionBits options,
+                                        IOByteCount offset, IOByteCount length )
+{
+    IOReturn err;
+
+    assert(offset <= _length);
+
+    if( offset >= _length)
+        return( kIOReturnOverrun );
+
+    LOCK;
+    err = _parent->performOperation( options, _start + offset,
+                                      min(length, _length - offset) );
+    UNLOCK;
+
+    return( err );
+}
+
+IOReturn IOSubMemoryDescriptor::prepare(
+		IODirection forDirection)
+{
+    IOReturn	err;
+
+    LOCK;
+    err = _parent->prepare( forDirection);
+    UNLOCK;
+
+    return( err );
+}
+
+IOReturn IOSubMemoryDescriptor::complete(
+		IODirection forDirection)
+{
+    IOReturn	err;
+
+    LOCK;
+    err = _parent->complete( forDirection);
+    UNLOCK;
+
+    return( err );
+}
+
+IOMemoryMap * IOSubMemoryDescriptor::makeMapping(
+	IOMemoryDescriptor *	owner,
+	task_t			intoTask,
+	IOVirtualAddress	toAddress,
+	IOOptionBits		options,
+	IOByteCount		offset,
+	IOByteCount		length )
+{
+    IOMemoryMap * mapping = 0;
+
+    if (!(kIOMapUnique & options))
+	mapping = (IOMemoryMap *) _parent->makeMapping(
+					_parent, intoTask,
+					toAddress - (_start + offset),
+					options | kIOMapReference,
+					_start + offset, length );
+
+    if( !mapping)
+        mapping = (IOMemoryMap *) _parent->makeMapping(
+					_parent, intoTask,
+					toAddress,
+					options, _start + offset, length );
+
+    if( !mapping)
+	mapping = super::makeMapping( owner, intoTask, toAddress, options,
+					offset, length );
+
+    return( mapping );
+}
+
+/* ick */
+
+bool
+IOSubMemoryDescriptor::initWithAddress(void *      address,
+                                    IOByteCount   length,
+                                    IODirection direction)
+{
+    return( false );
+}
+
+bool
+IOSubMemoryDescriptor::initWithAddress(vm_address_t address,
+                                    IOByteCount    length,
+                                    IODirection  direction,
+                                    task_t       task)
+{
+    return( false );
+}
+
+bool
+IOSubMemoryDescriptor::initWithPhysicalAddress(
+				 IOPhysicalAddress	address,
+				 IOByteCount		length,
+				 IODirection      	direction )
+{
+    return( false );
+}
+
+bool
+IOSubMemoryDescriptor::initWithRanges(
+                                   	IOVirtualRange * ranges,
+                                   	UInt32           withCount,
+                                   	IODirection      direction,
+                                   	task_t           task,
+                                  	bool             asReference)
+{
+    return( false );
+}
+
+bool
+IOSubMemoryDescriptor::initWithPhysicalRanges(	IOPhysicalRange * ranges,
+                                        	UInt32           withCount,
+                                        	IODirection      direction,
+                                        	bool             asReference)
+{
+    return( false );
+}
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+bool IOGeneralMemoryDescriptor::serialize(OSSerialize * s) const
+{
+    OSSymbol const *keys[2];
+    OSObject *values[2];
+    struct SerData {
+	user_addr_t address;
+	user_size_t length;
+    } *vcopy;
+    unsigned int index, nRanges;
+    bool result;
+
+    IOOptionBits type = _flags & kIOMemoryTypeMask;
+
+    if (s == NULL) return false;
+    if (s->previouslySerialized(this)) return true;
+
+    // Pretend we are an array.
+    if (!s->addXMLStartTag(this, "array")) return false;
+
+    nRanges = _rangesCount;
+    vcopy = (SerData *) IOMalloc(sizeof(SerData) * nRanges);
+    if (vcopy == 0) return false;
+
+    keys[0] = OSSymbol::withCString("address");
+    keys[1] = OSSymbol::withCString("length");
+
+    result = false;
+    values[0] = values[1] = 0;
+
+    // From this point on we can go to bail.
+
+    // Copy the volatile data so we don't have to allocate memory
+    // while the lock is held.
+    LOCK;
+    if (nRanges == _rangesCount) {
+	Ranges vec = _ranges;
+        for (index = 0; index < nRanges; index++) {
+	    user_addr_t addr; IOByteCount len;
+	    getAddrLenForInd(addr, len, type, vec, index);
+            vcopy[index].address = addr;
+            vcopy[index].length  = len;
+        }
+    } else {
+	// The descriptor changed out from under us.  Give up.
+        UNLOCK;
+	result = false;
+        goto bail;
+    }
+    UNLOCK;
+
+    for (index = 0; index < nRanges; index++)
+    {
+	user_addr_t addr = vcopy[index].address;
+	IOByteCount len = (IOByteCount) vcopy[index].length;
+	values[0] =
+	    OSNumber::withNumber(addr, (((UInt64) addr) >> 32)? 64 : 32);
+	if (values[0] == 0) {
+	  result = false;
+	  goto bail;
 	}
-
-#if DEBUG
+	values[1] = OSNumber::withNumber(len, sizeof(len) * 8);
+	if (values[1] == 0) {
+	  result = false;
+	  goto bail;
+	}
+        OSDictionary *dict = OSDictionary::withObjects((const OSObject **)values, (const OSSymbol **)keys, 2);
+	if (dict == 0) {
+	  result = false;
+	  goto bail;
+	}
+	values[0]->release();
+	values[1]->release();
+	values[0] = values[1] = 0;
+
+	result = dict->serialize(s);
+	dict->release();
 	if (!result) {
-		IOLog("createMappingInTask failed desc %p, addr %qx, options %x, offset %qx, length %llx\n",
-		    this, atAddress, (uint32_t) options, offset, length);
+	  goto bail;
 	}
-#endif
-
-	// already retained through makeMapping
-	OSSharedPtr<IOMemoryMap> retval(result, OSNoRetain);
-
-	return retval;
-}
-
-#ifndef __LP64__ // there is only a 64 bit version for LP64
-IOReturn
-IOMemoryMap::redirect(IOMemoryDescriptor * newBackingMemory,
-    IOOptionBits         options,
-    IOByteCount          offset)
-{
-	return redirect(newBackingMemory, options, (mach_vm_size_t)offset);
-}
-#endif
-
-IOReturn
-IOMemoryMap::redirect(IOMemoryDescriptor * newBackingMemory,
-    IOOptionBits         options,
-    mach_vm_size_t       offset)
-{
-	IOReturn err = kIOReturnSuccess;
-	OSSharedPtr<IOMemoryDescriptor> physMem;
-
-	LOCK;
-
-	if (fAddress && fAddressMap) {
-		do{
-			if (((fMemory->_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical)
-			    || ((fMemory->_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical64)) {
-				physMem = fMemory;
-			}
-
-			if (!fRedirUPL && fMemory->_memRef && (1 == fMemory->_memRef->count)) {
-				upl_size_t          size = (typeof(size))round_page(fLength);
-				upl_control_flags_t flags = UPL_COPYOUT_FROM | UPL_SET_INTERNAL
-				    | UPL_SET_LITE | UPL_SET_IO_WIRE | UPL_BLOCK_ACCESS;
-				if (KERN_SUCCESS != memory_object_iopl_request(fMemory->_memRef->entries[0].entry, 0, &size, &fRedirUPL,
-				    NULL, NULL,
-				    &flags, (vm_tag_t) fMemory->getVMTag(kernel_map))) {
-					fRedirUPL = NULL;
-				}
-
-				if (physMem) {
-					IOUnmapPages( fAddressMap, fAddress, fLength );
-					if ((false)) {
-						physMem->redirect(NULL, true);
-					}
-				}
-			}
-
-			if (newBackingMemory) {
-				if (newBackingMemory != fMemory) {
-					fOffset = 0;
-					if (this != newBackingMemory->makeMapping(newBackingMemory, fAddressTask, (IOVirtualAddress) this,
-					    options | kIOMapUnique | kIOMapReference | kIOMap64Bit,
-					    offset, fLength)) {
-						err = kIOReturnError;
-					}
-				}
-				if (fRedirUPL) {
-					upl_commit(fRedirUPL, NULL, 0);
-					upl_deallocate(fRedirUPL);
-					fRedirUPL = NULL;
-				}
-				if ((false) && physMem) {
-					physMem->redirect(NULL, false);
-				}
-			}
-		}while (false);
-	}
-
-	UNLOCK;
-
-	return err;
-}
-
-IOMemoryMap *
-IOMemoryDescriptor::makeMapping(
-	IOMemoryDescriptor *    owner,
-	task_t                  __intoTask,
-	IOVirtualAddress        __address,
-	IOOptionBits            options,
-	IOByteCount             __offset,
-	IOByteCount             __length )
-{
-#ifndef __LP64__
-	if (!(kIOMap64Bit & options)) {
-		panic("IOMemoryDescriptor::makeMapping !64bit");
-	}
-#endif /* !__LP64__ */
-
-	OSSharedPtr<IOMemoryDescriptor> mapDesc;
-	__block IOMemoryMap * result  = NULL;
-
-	IOMemoryMap *  mapping = (IOMemoryMap *) __address;
-	mach_vm_size_t offset  = mapping->fOffset + __offset;
-	mach_vm_size_t length  = mapping->fLength;
-
-	mapping->fOffset = offset;
-
-	LOCK;
-
-	do{
-		if (kIOMapStatic & options) {
-			result = mapping;
-			addMapping(mapping);
-			mapping->setMemoryDescriptor(this, 0);
-			continue;
-		}
-
-		if (kIOMapUnique & options) {
-			addr64_t phys;
-			IOByteCount       physLen;
-
-//	    if (owner != this)		continue;
-
-			if (((_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical)
-			    || ((_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical64)) {
-				phys = getPhysicalSegment(offset, &physLen, kIOMemoryMapperNone);
-				if (!phys || (physLen < length)) {
-					continue;
-				}
-
-				mapDesc = IOMemoryDescriptor::withAddressRange(
-					phys, length, getDirection() | kIOMemoryMapperNone, NULL);
-				if (!mapDesc) {
-					continue;
-				}
-				offset = 0;
-				mapping->fOffset = offset;
-			}
-		} else {
-			// look for a compatible existing mapping
-			if (_mappings) {
-				_mappings->iterateObjects(^(OSObject * object)
-				{
-					IOMemoryMap * lookMapping = (IOMemoryMap *) object;
-					if ((result = lookMapping->copyCompatible(mapping))) {
-					        addMapping(result);
-					        result->setMemoryDescriptor(this, offset);
-					        return true;
-					}
-					return false;
-				});
-			}
-			if (result || (options & kIOMapReference)) {
-				if (result != mapping) {
-					mapping->release();
-					mapping = NULL;
-				}
-				continue;
-			}
-		}
-
-		if (!mapDesc) {
-			mapDesc.reset(this, OSRetain);
-		}
-		IOReturn
-		    kr = mapDesc->doMap( NULL, (IOVirtualAddress *) &mapping, options, 0, 0 );
-		if (kIOReturnSuccess == kr) {
-			result = mapping;
-			mapDesc->addMapping(result);
-			result->setMemoryDescriptor(mapDesc.get(), offset);
-		} else {
-			mapping->release();
-			mapping = NULL;
-		}
-	}while (false);
-
-	UNLOCK;
-
-	return result;
-}
-
-void
-IOMemoryDescriptor::addMapping(
-	IOMemoryMap * mapping )
-{
-	if (mapping) {
-		if (NULL == _mappings) {
-			_mappings = OSSet::withCapacity(1);
-		}
-		if (_mappings) {
-			_mappings->setObject( mapping );
-		}
-	}
-}
-
-void
-IOMemoryDescriptor::removeMapping(
-	IOMemoryMap * mapping )
-{
-	if (_mappings) {
-		_mappings->removeObject( mapping);
-	}
-}
-
-void
-IOMemoryDescriptor::setMapperOptions( uint16_t options)
-{
-	_iomapperOptions = options;
-}
-
-uint16_t
-IOMemoryDescriptor::getMapperOptions( void )
-{
-	return _iomapperOptions;
-}
-
-#ifndef __LP64__
-// obsolete initializers
-// - initWithOptions is the designated initializer
-bool
-IOMemoryDescriptor::initWithAddress(void *      address,
-    IOByteCount   length,
-    IODirection direction)
-{
+    }
+    result = s->addXMLEndTag("array");
+
+ bail:
+    if (values[0])
+      values[0]->release();
+    if (values[1])
+      values[1]->release();
+    if (keys[0])
+      keys[0]->release();
+    if (keys[1])
+      keys[1]->release();
+    if (vcopy)
+        IOFree(vcopy, sizeof(IOVirtualRange) * nRanges);
+    return result;
+}
+
+bool IOSubMemoryDescriptor::serialize(OSSerialize * s) const
+{
+    if (!s) {
+	return (false);
+    }
+    if (s->previouslySerialized(this)) return true;
+
+    // Pretend we are a dictionary.
+    // We must duplicate the functionality of OSDictionary here
+    // because otherwise object references will not work;
+    // they are based on the value of the object passed to
+    // previouslySerialized and addXMLStartTag.
+
+    if (!s->addXMLStartTag(this, "dict")) return false;
+
+    char const *keys[3] = {"offset", "length", "parent"};
+
+    OSObject *values[3];
+    values[0] = OSNumber::withNumber(_start, sizeof(_start) * 8);
+    if (values[0] == 0)
 	return false;
-}
-
-bool
-IOMemoryDescriptor::initWithAddress(IOVirtualAddress address,
-    IOByteCount    length,
-    IODirection  direction,
-    task_t       task)
-{
+    values[1] = OSNumber::withNumber(_length, sizeof(_length) * 8);
+    if (values[1] == 0) {
+	values[0]->release();
 	return false;
-}
-
-bool
-IOMemoryDescriptor::initWithPhysicalAddress(
-	IOPhysicalAddress      address,
-	IOByteCount            length,
-	IODirection            direction )
-{
-	return false;
-}
-
-bool
-IOMemoryDescriptor::initWithRanges(
-	IOVirtualRange * ranges,
-	UInt32           withCount,
-	IODirection      direction,
-	task_t           task,
-	bool             asReference)
-{
-	return false;
-}
-
-bool
-IOMemoryDescriptor::initWithPhysicalRanges(     IOPhysicalRange * ranges,
-    UInt32           withCount,
-    IODirection      direction,
-    bool             asReference)
-{
-	return false;
-}
-
-void *
-IOMemoryDescriptor::getVirtualSegment(IOByteCount offset,
-    IOByteCount * lengthOfSegment)
-{
-	return NULL;
-}
-#endif /* !__LP64__ */
+    }
+    values[2] = _parent;
+
+    bool result = true;
+    for (int i=0; i<3; i++) {
+        if (!s->addString("<key>") ||
+	    !s->addString(keys[i]) ||
+	    !s->addXMLEndTag("key") ||
+	    !values[i]->serialize(s)) {
+	  result = false;
+	  break;
+        }
+    }
+    values[0]->release();
+    values[1]->release();
+    if (!result) {
+      return false;
+    }
+
+    return s->addXMLEndTag("dict");
+}
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-bool
-IOGeneralMemoryDescriptor::serialize(OSSerialize * s) const
-{
-	OSSharedPtr<OSSymbol const>     keys[2] = {NULL};
-	OSSharedPtr<OSObject>           values[2] = {NULL};
-	OSSharedPtr<OSArray>            array;
-
-	struct SerData {
-		user_addr_t address;
-		user_size_t length;
-	};
-
-	unsigned int index;
-
-	IOOptionBits type = _flags & kIOMemoryTypeMask;
-
-	if (s == NULL) {
-		return false;
-	}
-
-	array = OSArray::withCapacity(4);
-	if (!array) {
-		return false;
-	}
-
-	OSDataAllocation<struct SerData> vcopy(_rangesCount, OSAllocateMemory);
-	if (!vcopy) {
-		return false;
-	}
-
-	keys[0] = OSSymbol::withCString("address");
-	keys[1] = OSSymbol::withCString("length");
-
-	// Copy the volatile data so we don't have to allocate memory
-	// while the lock is held.
-	LOCK;
-	if (vcopy.size() == _rangesCount) {
-		Ranges vec = _ranges;
-		for (index = 0; index < vcopy.size(); index++) {
-			mach_vm_address_t addr; mach_vm_size_t len;
-			getAddrLenForInd(addr, len, type, vec, index, _task);
-			if ((kIOMemoryTypePhysical == type) || (kIOMemoryTypePhysical64 == type)) {
-				vcopy[index].address = addr;
-			} else {
-				vcopy[index].address = VM_KERNEL_ADDRHIDE(addr);
-			}
-			vcopy[index].length  = len;
-		}
-	} else {
-		// The descriptor changed out from under us.  Give up.
-		UNLOCK;
-		return false;
-	}
-	UNLOCK;
-
-	for (index = 0; index < vcopy.size(); index++) {
-		user_addr_t addr = vcopy[index].address;
-		IOByteCount len = (IOByteCount) vcopy[index].length;
-		values[0] = OSNumber::withNumber(addr, sizeof(addr) * 8);
-		if (values[0] == NULL) {
-			return false;
-		}
-		values[1] = OSNumber::withNumber(len, sizeof(len) * 8);
-		if (values[1] == NULL) {
-			return false;
-		}
-		OSSharedPtr<OSDictionary> dict = OSDictionary::withObjects((const OSObject **)values, (const OSSymbol **)keys, 2);
-		if (dict == NULL) {
-			return false;
-		}
-		array->setObject(dict.get());
-		dict.reset();
-		values[0].reset();
-		values[1].reset();
-	}
-
-	return array->serialize(s);
-}
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-OSMetaClassDefineReservedUsedX86(IOMemoryDescriptor, 0);
-#ifdef __LP64__
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 1);
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 2);
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 3);
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 4);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 0);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 1);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 2);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 3);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 4);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 5);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 6);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 7);
-#else /* !__LP64__ */
-OSMetaClassDefineReservedUsedX86(IOMemoryDescriptor, 1);
-OSMetaClassDefineReservedUsedX86(IOMemoryDescriptor, 2);
-OSMetaClassDefineReservedUsedX86(IOMemoryDescriptor, 3);
-OSMetaClassDefineReservedUsedX86(IOMemoryDescriptor, 4);
-OSMetaClassDefineReservedUsedX86(IOMemoryDescriptor, 5);
-OSMetaClassDefineReservedUsedX86(IOMemoryDescriptor, 6);
-OSMetaClassDefineReservedUsedX86(IOMemoryDescriptor, 7);
-#endif /* !__LP64__ */
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 8);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 9);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 10);
@@ -6526,119 +3340,6 @@
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 14);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 15);
 
-/* for real this is a ioGMDData + upl_page_info_t + ioPLBlock */
-KALLOC_TYPE_VAR_DEFINE(KT_IOMD_MIXED_DATA,
-    struct ioGMDData, struct ioPLBlock, KT_DEFAULT);
-
 /* ex-inline function implementation */
-IOPhysicalAddress
-IOMemoryDescriptor::getPhysicalAddress()
-{
-	return getPhysicalSegment( 0, NULL );
-}
-
-OSDefineMetaClassAndStructors(_IOMemoryDescriptorMixedData, OSObject)
-
-OSPtr<_IOMemoryDescriptorMixedData>
-_IOMemoryDescriptorMixedData::withCapacity(size_t capacity)
-{
-	OSSharedPtr<_IOMemoryDescriptorMixedData> me = OSMakeShared<_IOMemoryDescriptorMixedData>();
-	if (me && !me->initWithCapacity(capacity)) {
-		return nullptr;
-	}
-	return me;
-}
-
-bool
-_IOMemoryDescriptorMixedData::initWithCapacity(size_t capacity)
-{
-	if (_data && (!capacity || (_capacity < capacity))) {
-		freeMemory();
-	}
-
-	if (!OSObject::init()) {
-		return false;
-	}
-
-	if (!_data && capacity) {
-		_data = kalloc_type_var_impl(KT_IOMD_MIXED_DATA, capacity,
-		    Z_VM_TAG_BT(Z_WAITOK_ZERO, VM_KERN_MEMORY_IOKIT), NULL);
-		if (!_data) {
-			return false;
-		}
-		_capacity = capacity;
-	}
-
-	_length = 0;
-
-	return true;
-}
-
-void
-_IOMemoryDescriptorMixedData::free()
-{
-	freeMemory();
-	OSObject::free();
-}
-
-void
-_IOMemoryDescriptorMixedData::freeMemory()
-{
-	kfree_type_var_impl(KT_IOMD_MIXED_DATA, _data, _capacity);
-	_data = nullptr;
-	_capacity = _length = 0;
-}
-
-bool
-_IOMemoryDescriptorMixedData::appendBytes(const void * bytes, size_t length)
-{
-	const auto oldLength = getLength();
-	size_t newLength;
-	if (os_add_overflow(oldLength, length, &newLength)) {
-		return false;
-	}
-
-	if (!setLength(newLength)) {
-		return false;
-	}
-
-	unsigned char * const dest = &(((unsigned char *)_data)[oldLength]);
-	if (bytes) {
-		bcopy(bytes, dest, length);
-	}
-
-	return true;
-}
-
-bool
-_IOMemoryDescriptorMixedData::setLength(size_t length)
-{
-	if (!_data || (length > _capacity)) {
-		void *newData;
-
-		newData = __krealloc_type(KT_IOMD_MIXED_DATA, _data, _capacity,
-		    length, Z_VM_TAG_BT(Z_WAITOK_ZERO, VM_KERN_MEMORY_IOKIT),
-		    NULL);
-		if (!newData) {
-			return false;
-		}
-
-		_data = newData;
-		_capacity = length;
-	}
-
-	_length = length;
-	return true;
-}
-
-const void *
-_IOMemoryDescriptorMixedData::getBytes() const
-{
-	return _length ? _data : nullptr;
-}
-
-size_t
-_IOMemoryDescriptorMixedData::getLength() const
-{
-	return _data ? _length : 0;
-}
+IOPhysicalAddress IOMemoryDescriptor::getPhysicalAddress()
+        { return( getPhysicalSegment( 0, 0 )); }