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iokit/Kernel/IOBufferMemoryDescriptor.cpp xnu-517.7.21 xnu-2050.9.2
--- xnu/xnu-517.7.21/iokit/Kernel/IOBufferMemoryDescriptor.cpp
+++ xnu/xnu-2050.9.2/iokit/Kernel/IOBufferMemoryDescriptor.cpp
@@ -1,223 +1,286 @@
 /*
  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
  * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
  * 
- * @APPLE_LICENSE_HEADER_END@
- */
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
+
+#define _IOMEMORYDESCRIPTOR_INTERNAL_
+
 #include <IOKit/assert.h>
 #include <IOKit/system.h>
 
 #include <IOKit/IOLib.h>
+#include <IOKit/IOMapper.h>
 #include <IOKit/IOBufferMemoryDescriptor.h>
+#include <libkern/OSDebug.h>
+
+#include "IOKitKernelInternal.h"
 
 __BEGIN_DECLS
 void ipc_port_release_send(ipc_port_t port);
 #include <vm/pmap.h>
 
-vm_map_t IOPageableMapForAddress( vm_address_t address );
 __END_DECLS
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+enum
+{
+    kInternalFlagPhysical  = 0x00000001,
+    kInternalFlagPageSized = 0x00000002
+};
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
 #define super IOGeneralMemoryDescriptor
 OSDefineMetaClassAndStructors(IOBufferMemoryDescriptor,
 				IOGeneralMemoryDescriptor);
 
-bool IOBufferMemoryDescriptor::initWithAddress(
-                                  void *      /* address       */ ,
-                                  IOByteCount /* withLength    */ ,
-                                  IODirection /* withDirection */ )
-{
-    return false;
-}
-
-bool IOBufferMemoryDescriptor::initWithAddress(
-                                  vm_address_t /* address       */ ,
-                                  IOByteCount  /* withLength    */ ,
-                                  IODirection  /* withDirection */ ,
-                                  task_t       /* withTask      */ )
-{
-    return false;
-}
-
-bool IOBufferMemoryDescriptor::initWithPhysicalAddress(
-                                  IOPhysicalAddress /* address       */ ,
-                                  IOByteCount       /* withLength    */ ,
-                                  IODirection       /* withDirection */ )
-{
-    return false;
-}
-
-bool IOBufferMemoryDescriptor::initWithPhysicalRanges(
-                                  IOPhysicalRange * /* ranges        */ ,
-                                  UInt32            /* withCount     */ ,
-                                  IODirection       /* withDirection */ ,
-                                  bool              /* asReference   */ )
-{
-    return false;
-}
-
-bool IOBufferMemoryDescriptor::initWithRanges(
-                                  IOVirtualRange * /* ranges        */ ,
-                                  UInt32           /* withCount     */ ,
-                                  IODirection      /* withDirection */ ,
-                                  task_t           /* withTask      */ ,
-                                  bool             /* asReference   */ )
-{
-    return false;
-}
-
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+#ifndef __LP64__
 bool IOBufferMemoryDescriptor::initWithOptions(
                                IOOptionBits options,
                                vm_size_t    capacity,
                                vm_offset_t  alignment,
 			       task_t	    inTask)
 {
-    vm_map_t map = 0;
-    IOOptionBits iomdOptions = kIOMemoryAsReference | kIOMemoryTypeVirtual;
+    mach_vm_address_t physicalMask = 0;
+    return (initWithPhysicalMask(inTask, options, capacity, alignment, physicalMask));
+}
+#endif /* !__LP64__ */
+
+bool IOBufferMemoryDescriptor::initWithPhysicalMask(
+				task_t		  inTask,
+				IOOptionBits      options,
+				mach_vm_size_t    capacity,
+				mach_vm_address_t alignment,
+				mach_vm_address_t physicalMask)
+{
+    kern_return_t 	kr;
+    task_t		mapTask = NULL;
+    vm_map_t 		vmmap = NULL;
+    mach_vm_address_t   highestMask = 0;
+    IOOptionBits	iomdOptions = kIOMemoryTypeVirtual64 | kIOMemoryAsReference;
 
     if (!capacity)
         return false;
 
-    _options   	  = options;
-    _capacity     = capacity;
-    _physAddrs    = 0;
-    _physSegCount = 0;
-    _buffer	  = 0;
-
-    // Grab the direction and the Auto Prepare bits from the Buffer MD options
-    iomdOptions  |= options & (kIOMemoryDirectionMask | kIOMemoryAutoPrepare);
-
-    if ((options & kIOMemorySharingTypeMask) && (alignment < page_size))
-        alignment = page_size;
+    _options   	      = options;
+    _capacity         = capacity;
+    _internalFlags    = 0;
+    _internalReserved = 0;
+    _buffer	      = 0;
+
+    _ranges.v64 = IONew(IOAddressRange, 1);
+    if (!_ranges.v64)
+	return (false);
+    _ranges.v64->address = 0;
+    _ranges.v64->length  = 0;
+	//  make sure super::free doesn't dealloc _ranges before super::init
+	_flags = kIOMemoryAsReference;
+
+    // Grab IOMD bits from the Buffer MD options
+    iomdOptions  |= (options & kIOBufferDescriptorMemoryFlags);
+
+    if (physicalMask && (alignment <= 1))
+    {
+	alignment   = ((physicalMask ^ (-1ULL)) & (physicalMask - 1));
+	highestMask = (physicalMask | alignment);
+	alignment++;
+	if (alignment < page_size)
+            alignment = page_size;
+    }
+
+    if ((options & (kIOMemorySharingTypeMask | kIOMapCacheMask | kIOMemoryClearEncrypt)) && (alignment < page_size))
+	alignment = page_size;
+
+    if (alignment >= page_size)
+	capacity = round_page(capacity);
+
+    if (alignment > page_size)
+	options |= kIOMemoryPhysicallyContiguous;
+
+    _alignment = alignment;
 
     if ((inTask != kernel_task) && !(options & kIOMemoryPageable))
-        return false;
-
-    _alignment = alignment;
+	return false;
+
+    // set flags for entry + object create
+    vm_prot_t memEntryCacheMode = VM_PROT_READ | VM_PROT_WRITE;
+
+    // set memory entry cache mode
+    switch (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 kIOMapCopybackInnerCache:
+	    SET_MAP_MEM(MAP_MEM_INNERWBACK, memEntryCacheMode);
+	    break;
+
+	case kIOMapDefaultCache:
+	default:
+	    SET_MAP_MEM(MAP_MEM_NOOP, memEntryCacheMode);
+	    break;
+    }
+
     if (options & kIOMemoryPageable)
     {
-        iomdOptions |= kIOMemoryBufferPageable;
-	if (inTask == kernel_task)
+	iomdOptions |= kIOMemoryBufferPageable;
+
+	// must create the entry before any pages are allocated
+
+	// set flags for entry + object create
+	memEntryCacheMode |= MAP_MEM_NAMED_CREATE;
+
+	if (options & kIOMemoryPurgeable)
+	    memEntryCacheMode |= MAP_MEM_PURGABLE;
+    }
+    else
+    {
+	memEntryCacheMode |= MAP_MEM_NAMED_REUSE;
+	vmmap = kernel_map;
+
+	// Buffer shouldn't auto prepare they should be prepared explicitly
+	// But it never was enforced so what are you going to do?
+	iomdOptions |= kIOMemoryAutoPrepare;
+
+	/* Allocate a wired-down buffer inside kernel space. */
+
+	if ((options & kIOMemoryPhysicallyContiguous) || highestMask || (alignment > page_size))
 	{
-	    /* Allocate some kernel address space. */
-	    _buffer = IOMallocPageable(capacity, alignment);
-	    if (_buffer)
-		map = IOPageableMapForAddress((vm_address_t) _buffer);
+            _internalFlags |= kInternalFlagPhysical;
+            if (highestMask)
+            {
+                _internalFlags |= kInternalFlagPageSized;
+                capacity = round_page(capacity);
+            }
+            _buffer = (void *) IOKernelAllocateWithPhysicalRestrict(capacity, highestMask, alignment, 
+                                        (0 != (options & kIOMemoryPhysicallyContiguous)));
+	}
+	else if (alignment > 1)
+	{
+            _buffer = IOMallocAligned(capacity, alignment);
 	}
 	else
 	{
-	    kern_return_t kr;
-
-	    if( !reserved) {
-		reserved = IONew( ExpansionData, 1 );
-		if( !reserved)
-		    return( false );
+            _buffer = IOMalloc(capacity);
+	}
+
+	if (!_buffer)
+	{
+            return false;
+	}
+    }
+
+    if( (options & (kIOMemoryPageable | kIOMapCacheMask))) {
+	ipc_port_t	sharedMem;
+	vm_size_t	size = round_page(capacity);
+
+	kr = mach_make_memory_entry(vmmap,
+				    &size, (vm_offset_t)_buffer,
+				    memEntryCacheMode, &sharedMem,
+				    NULL );
+
+	if( (KERN_SUCCESS == kr) && (size != round_page(capacity))) {
+	    ipc_port_release_send( sharedMem );
+	    kr = kIOReturnVMError;
+	}
+	if( KERN_SUCCESS != kr)
+	    return( false );
+
+	_memEntry = (void *) sharedMem;
+
+	if( options & kIOMemoryPageable) {
+#if IOALLOCDEBUG
+	    debug_iomallocpageable_size += size;
+#endif
+	    mapTask = inTask;
+	    if (NULL == inTask)
+		inTask = kernel_task;
+	}
+	else if (options & kIOMapCacheMask)
+	{
+	    // Prefetch each page to put entries into the pmap
+	    volatile UInt8 *	startAddr = (UInt8 *)_buffer;
+	    volatile UInt8 *	endAddr   = (UInt8 *)_buffer + capacity;
+
+	    while (startAddr < endAddr)
+	    {
+		*startAddr;
+		startAddr += page_size;
 	    }
-	    map = get_task_map(inTask);
-	    vm_map_reference(map);
-	    reserved->map = map;
-	    kr = vm_allocate( map, (vm_address_t *) &_buffer, round_page_32(capacity),
-				VM_FLAGS_ANYWHERE | VM_MAKE_TAG(VM_MEMORY_IOKIT) );
-	    if( KERN_SUCCESS != kr)
+	}
+    }
+
+    _ranges.v64->address = (mach_vm_address_t) _buffer;;
+    _ranges.v64->length  = _capacity;
+
+    if (!super::initWithOptions(_ranges.v64, 1, 0,
+				inTask, iomdOptions, /* System mapper */ 0))
+	return false;
+
+    if (mapTask)
+    {
+	if (!reserved) {
+	    reserved = IONew( ExpansionData, 1 );
+	    if( !reserved)
 		return( false );
-
-	    // we have to make sure that these pages don't get copied on fork.
-	    kr = vm_inherit( map, (vm_address_t) _buffer, round_page_32(capacity), VM_INHERIT_NONE);
-	    if( KERN_SUCCESS != kr)
-		return( false );
-	}
-    }
-    else 
-    {
-        // @@@ gvdl: Need to remove this
-        // Buffer should never auto prepare they should be prepared explicitly
-        // But it never was enforced so what are you going to do?
-        iomdOptions |= kIOMemoryAutoPrepare;
-
-	/* Allocate a wired-down buffer inside kernel space. */
-	if (options & kIOMemoryPhysicallyContiguous)
-	    _buffer = IOMallocContiguous(capacity, alignment, 0);
-	else if (alignment > 1)
-	    _buffer = IOMallocAligned(capacity, alignment);
-	else
-	    _buffer = IOMalloc(capacity);
-    }
-
-    if (!_buffer)
-	return false;
-
-    _singleRange.v.address = (vm_address_t) _buffer;
-    _singleRange.v.length  = capacity;
-
-    if (!super::initWithOptions(&_singleRange.v, 1, 0,
-                               inTask, iomdOptions, /* System mapper */ 0))
-	return false;
-
-    if (options & kIOMemoryPageable) {
-        kern_return_t kr;
-        ipc_port_t sharedMem = (ipc_port_t) _memEntry;
-        vm_size_t size = round_page_32(_ranges.v[0].length);
-
-        // must create the entry before any pages are allocated
-        if( 0 == sharedMem) {
-
-            // set memory entry cache
-            vm_prot_t memEntryCacheMode = VM_PROT_READ | VM_PROT_WRITE;
-            switch (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;
-            }
-
-            kr = mach_make_memory_entry( map,
-                        &size, _ranges.v[0].address,
-                        memEntryCacheMode, &sharedMem,
-                        NULL );
-
-            if( (KERN_SUCCESS == kr) && (size != round_page_32(_ranges.v[0].length))) {
-                ipc_port_release_send( sharedMem );
-                kr = kIOReturnVMError;
-            }
-            if( KERN_SUCCESS != kr)
-                sharedMem = 0;
-            _memEntry = (void *) sharedMem;
-        }
-    }
-
-    setLength(capacity);
-    
+	}
+	reserved->map = createMappingInTask(mapTask, 0, 
+			    kIOMapAnywhere | (options & kIOMapCacheMask), 0, 0);
+	if (!reserved->map)
+	{
+	    _buffer = 0;
+	    return( false );
+	}
+	release();	    // map took a retain on this
+	reserved->map->retain();
+	removeMapping(reserved->map);
+	mach_vm_address_t buffer = reserved->map->getAddress();
+	_buffer = (void *) buffer;
+	if (kIOMemoryTypeVirtual64 == (kIOMemoryTypeMask & iomdOptions))
+	    _ranges.v64->address = buffer;
+    }
+
+    setLength(_capacity);
+
     return true;
 }
 
@@ -229,20 +292,38 @@
 {
     IOBufferMemoryDescriptor *me = new IOBufferMemoryDescriptor;
     
-    if (me && !me->initWithOptions(options, capacity, alignment, inTask)) {
+    if (me && !me->initWithPhysicalMask(inTask, options, capacity, alignment, 0)) {
 	me->release();
 	me = 0;
     }
     return me;
 }
 
+IOBufferMemoryDescriptor * IOBufferMemoryDescriptor::inTaskWithPhysicalMask(
+					    task_t	      inTask,
+                                            IOOptionBits      options,
+                                            mach_vm_size_t    capacity,
+                                            mach_vm_address_t physicalMask)
+{
+    IOBufferMemoryDescriptor *me = new IOBufferMemoryDescriptor;
+    
+    if (me && !me->initWithPhysicalMask(inTask, options, capacity, 1, physicalMask))
+    {
+	me->release();
+	me = 0;
+    }
+    return me;
+}
+
+#ifndef __LP64__
 bool IOBufferMemoryDescriptor::initWithOptions(
                                IOOptionBits options,
                                vm_size_t    capacity,
                                vm_offset_t  alignment)
 {
-    return( initWithOptions(options, capacity, alignment, kernel_task) );
-}
+    return (initWithPhysicalMask(kernel_task, options, capacity, alignment, (mach_vm_address_t)0));
+}
+#endif /* !__LP64__ */
 
 IOBufferMemoryDescriptor * IOBufferMemoryDescriptor::withOptions(
                                             IOOptionBits options,
@@ -251,7 +332,7 @@
 {
     IOBufferMemoryDescriptor *me = new IOBufferMemoryDescriptor;
     
-    if (me && !me->initWithOptions(options, capacity, alignment, kernel_task)) {
+    if (me && !me->initWithPhysicalMask(kernel_task, options, capacity, alignment, 0)) {
 	me->release();
 	me = 0;
     }
@@ -276,6 +357,7 @@
                inCapacity, inContiguous ? inCapacity : 1 ));
 }
 
+#ifndef __LP64__
 /*
  * initWithBytes:
  *
@@ -287,10 +369,9 @@
                                              IODirection  inDirection,
                                              bool         inContiguous)
 {
-    if (!initWithOptions(
-               inDirection | kIOMemoryUnshared
-                | (inContiguous ? kIOMemoryPhysicallyContiguous : 0),
-               inLength, inLength ))
+    if (!initWithPhysicalMask(kernel_task, inDirection | kIOMemoryUnshared
+			      | (inContiguous ? kIOMemoryPhysicallyContiguous : 0),
+			      inLength, inLength, (mach_vm_address_t)0))
         return false;
 
     // start out with no data
@@ -301,6 +382,7 @@
 
     return true;
 }
+#endif /* !__LP64__ */
 
 /*
  * withBytes:
@@ -316,9 +398,25 @@
 {
     IOBufferMemoryDescriptor *me = new IOBufferMemoryDescriptor;
 
-    if (me && !me->initWithBytes(inBytes, inLength, inDirection, inContiguous)){
-        me->release();
-        me = 0;
+    if (me && !me->initWithPhysicalMask(
+               kernel_task, inDirection | kIOMemoryUnshared
+                | (inContiguous ? kIOMemoryPhysicallyContiguous : 0),
+               inLength, inLength, 0 ))
+    {
+	me->release();
+	me = 0;
+    }
+
+    if (me)
+    {
+	// start out with no data
+	me->setLength(0);
+
+	if (!me->appendBytes(inBytes, inLength))
+	{
+	    me->release();
+	    me = 0;
+	}
     }
     return me;
 }
@@ -332,42 +430,50 @@
 {
     // Cache all of the relevant information on the stack for use
     // after we call super::free()!
-    IOOptionBits options   = _options;
-    vm_size_t    size	   = _capacity;
-    void *       buffer	   = _buffer;
-    vm_map_t	 map	   = 0;
-    vm_offset_t  alignment = _alignment;
+    IOOptionBits     flags         = _flags;
+    IOOptionBits     internalFlags = _internalFlags;
+    IOOptionBits     options   = _options;
+    vm_size_t        size      = _capacity;
+    void *           buffer    = _buffer;
+    IOMemoryMap *    map       = 0;
+    IOAddressRange * range     = _ranges.v64;
+    vm_offset_t      alignment = _alignment;
+
+    if (alignment >= page_size)
+	size = round_page(size);
 
     if (reserved)
     {
 	map = reserved->map;
         IODelete( reserved, ExpansionData, 1 );
+	if (map)
+	    map->release();
     }
 
     /* super::free may unwire - deallocate buffer afterwards */
     super::free();
 
-    if (buffer)
-    {
-        if (options & kIOMemoryPageable)
-	{
-	    if (map)
-		vm_deallocate(map, (vm_address_t) buffer, round_page_32(size));
-	    else
-	       IOFreePageable(buffer, size);
-	}
+    if (options & kIOMemoryPageable)
+    {
+#if IOALLOCDEBUG
+	debug_iomallocpageable_size -= round_page(size);
+#endif
+    }
+    else if (buffer)
+    {
+        if (internalFlags & kInternalFlagPhysical)
+        {
+            if (kInternalFlagPageSized & internalFlags)
+                size = round_page(size);
+            IOKernelFreePhysical((mach_vm_address_t) buffer, size);
+        }
+        else if (alignment > 1)
+            IOFreeAligned(buffer, size);
         else
-	{
-            if (options & kIOMemoryPhysicallyContiguous)
-                IOFreeContiguous(buffer, size);
-            else if (alignment > 1)
-                IOFreeAligned(buffer, size);
-            else
-                IOFree(buffer, size);
-        }
-    }
-    if (map)
-	vm_map_deallocate(map);
+            IOFree(buffer, size);
+    }
+    if (range && (kIOMemoryAsReference & flags))
+	IODelete(range, IOAddressRange, 1);
 }
 
 /*
@@ -395,7 +501,7 @@
     assert(length <= _capacity);
 
     _length = length;
-    _singleRange.v.length = length;
+    _ranges.v64->length = length;
 }
 
 /*
@@ -407,7 +513,10 @@
  */
 void IOBufferMemoryDescriptor::setDirection(IODirection direction)
 {
-    _direction = direction;
+    _flags = (_flags & ~kIOMemoryDirectionMask) | direction;
+#ifndef __LP64__
+    _direction = (IODirection) (_flags & kIOMemoryDirectionMask);
+#endif /* !__LP64__ */
 }
 
 /*
@@ -420,13 +529,20 @@
 bool
 IOBufferMemoryDescriptor::appendBytes(const void * bytes, vm_size_t withLength)
 {
-    vm_size_t actualBytesToCopy = min(withLength, _capacity - _length);
+    vm_size_t   actualBytesToCopy = min(withLength, _capacity - _length);
+    IOByteCount offset;
 
     assert(_length <= _capacity);
-    bcopy(/* from */ bytes, (void *)(_singleRange.v.address + _length),
-          actualBytesToCopy);
+
+    offset = _length;
     _length += actualBytesToCopy;
-    _singleRange.v.length += actualBytesToCopy;
+    _ranges.v64->length += actualBytesToCopy;
+
+    if (_task == kernel_task)
+	bcopy(/* from */ bytes, (void *)(_ranges.v64->address + offset),
+	      actualBytesToCopy);
+    else
+	writeBytes(offset, bytes, actualBytesToCopy);
 
     return true;
 }
@@ -438,8 +554,12 @@
  */
 void * IOBufferMemoryDescriptor::getBytesNoCopy()
 {
-    return (void *)_singleRange.v.address;
-}
+    if (kIOMemoryTypePhysical64 == (_flags & kIOMemoryTypeMask))
+	return _buffer;
+    else
+	return (void *)_ranges.v64->address;
+}
+
 
 /*
  * getBytesNoCopy:
@@ -449,13 +569,37 @@
 void *
 IOBufferMemoryDescriptor::getBytesNoCopy(vm_size_t start, vm_size_t withLength)
 {
-    if (start < _length && (start + withLength) <= _length)
-        return (void *)(_singleRange.v.address + start);
+    IOVirtualAddress address;
+    if (kIOMemoryTypePhysical64 == (_flags & kIOMemoryTypeMask))
+	address = (IOVirtualAddress) _buffer;
+    else
+	address = _ranges.v64->address;
+
+   if (start < _length && (start + withLength) <= _length)
+        return (void *)(address + start);
     return 0;
 }
 
+#ifndef __LP64__
+void * IOBufferMemoryDescriptor::getVirtualSegment(IOByteCount offset,
+							IOByteCount * lengthOfSegment)
+{
+    void * bytes = getBytesNoCopy(offset, 0);
+    
+    if (bytes && lengthOfSegment)
+	*lengthOfSegment = _length - offset;
+
+    return bytes;
+}
+#endif /* !__LP64__ */
+
+#ifdef __LP64__
+OSMetaClassDefineReservedUnused(IOBufferMemoryDescriptor, 0);
+OSMetaClassDefineReservedUnused(IOBufferMemoryDescriptor, 1);
+#else /* !__LP64__ */
 OSMetaClassDefineReservedUsed(IOBufferMemoryDescriptor, 0);
-OSMetaClassDefineReservedUnused(IOBufferMemoryDescriptor, 1);
+OSMetaClassDefineReservedUsed(IOBufferMemoryDescriptor, 1);
+#endif /* !__LP64__ */
 OSMetaClassDefineReservedUnused(IOBufferMemoryDescriptor, 2);
 OSMetaClassDefineReservedUnused(IOBufferMemoryDescriptor, 3);
 OSMetaClassDefineReservedUnused(IOBufferMemoryDescriptor, 4);