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[apple/xnu.git] / iokit / Kernel / IOMemoryDescriptor.cpp
index 129b53f23094b214d501b42fa25c1f1c14670949..389d75a1e3c6c03673c13508df7aa83b83189062 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1998-2004 Apple Computer, Inc. All rights reserved.
  *
  * @APPLE_LICENSE_HEADER_START@
  * 
  * HISTORY
  *
  */
+// 45678901234567890123456789012345678901234567890123456789012345678901234567890
+#include <sys/cdefs.h>
 
 #include <IOKit/assert.h>
 #include <IOKit/system.h>
 #include <IOKit/IOLib.h>
 #include <IOKit/IOMemoryDescriptor.h>
+#include <IOKit/IOMapper.h>
+#include <IOKit/IOKitKeysPrivate.h>
 
 #include <IOKit/IOKitDebug.h>
 
+#include "IOKitKernelInternal.h"
+
 #include <libkern/c++/OSContainers.h>
-#include <sys/cdefs.h>
+#include <libkern/c++/OSDictionary.h>
+#include <libkern/c++/OSArray.h>
+#include <libkern/c++/OSSymbol.h>
+#include <libkern/c++/OSNumber.h>
+
+#include <sys/uio.h>
 
 __BEGIN_DECLS
 #include <vm/pmap.h>
-void pmap_enter(pmap_t pmap, vm_offset_t va, vm_offset_t pa,
-                vm_prot_t prot, boolean_t wired);
+#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 <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);
-vm_offset_t vm_map_get_phys_page(vm_map_t map, vm_offset_t offset);
+
+/* 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 kIOMaximumMappedIOByteCount    (512*1024*1024)
+
+static IOMapper * gIOSystemMapper;
+static ppnum_t   gIOMaximumMappedIOPageCount = atop_32(kIOMaximumMappedIOByteCount);
+
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-OSDefineMetaClass( IOMemoryDescriptor, OSObject )
-OSDefineAbstractStructors( IOMemoryDescriptor, OSObject )
+OSDefineMetaClassAndAbstractStructors( IOMemoryDescriptor, OSObject )
 
 #define super IOMemoryDescriptor
 
 OSDefineMetaClassAndStructors(IOGeneralMemoryDescriptor, IOMemoryDescriptor)
 
-extern "C" vm_map_t IOPageableMapForAddress( vm_address_t address );
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+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 );
+};
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-inline vm_map_t IOGeneralMemoryDescriptor::getMapForTask( task_t task, vm_address_t address )
+// Some data structures and accessor macros used by the initWithOptions
+// Function
+
+enum ioPLBlockFlags {
+    kIOPLOnDevice  = 0x00000001,
+    kIOPLExternUPL = 0x00000002,
+};
+
+struct typePersMDData
 {
-    if( (task == kernel_task) && (kIOMemoryRequiresWire & _flags))
-        return( IOPageableMapForAddress( address ) );
+    const IOGeneralMemoryDescriptor *fMD;
+    ipc_port_t fMemEntry;
+};
+
+struct ioPLBlock {
+    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
+};
+
+struct ioGMDData {
+    IOMapper *fMapper;
+    unsigned int fPageCnt;
+    upl_page_info_t fPageList[];
+    ioPLBlock fBlocks[];
+};
+
+#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) \
+    (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(
+               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
-        return( get_task_map( task ));
+       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(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;
+    }
 }
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
@@ -76,13 +315,23 @@ inline vm_map_t IOGeneralMemoryDescriptor::getMapForTask( task_t task, vm_addres
  */
 IOMemoryDescriptor *
 IOMemoryDescriptor::withAddress(void *      address,
-                                IOByteCount   withLength,
-                                IODirection withDirection)
+                                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, withLength, withDirection))
+       if (that->initWithAddress(address, length, direction, task))
            return that;
 
         that->release();
@@ -91,15 +340,32 @@ IOMemoryDescriptor::withAddress(void *      address,
 }
 
 IOMemoryDescriptor *
-IOMemoryDescriptor::withAddress(vm_address_t address,
-                                IOByteCount  withLength,
-                                IODirection  withDirection,
-                                task_t       withTask)
+IOMemoryDescriptor::withPhysicalAddress(
+                               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->initWithAddress(address, withLength, withDirection, withTask))
+       if (that->initWithRanges(ranges, withCount, direction, task, asReference))
            return that;
 
         that->release();
@@ -107,16 +373,6 @@ IOMemoryDescriptor::withAddress(vm_address_t address,
     return 0;
 }
 
-IOMemoryDescriptor *
-IOMemoryDescriptor::withPhysicalAddress(
-                               IOPhysicalAddress       address,
-                               IOByteCount             withLength,
-                               IODirection             withDirection )
-{
-    return( IOMemoryDescriptor::withAddress( address, withLength,
-                                       withDirection, (task_t) 0  ));
-}
-
 
 /*
  * withRanges:
@@ -127,33 +383,48 @@ IOMemoryDescriptor::withPhysicalAddress(
  * Passing the ranges as a reference will avoid an extra allocation.
  */
 IOMemoryDescriptor *
-IOMemoryDescriptor::withRanges(        IOVirtualRange * ranges,
-                               UInt32           withCount,
-                               IODirection      withDirection,
-                               task_t           withTask,
-                               bool             asReference = false)
+IOMemoryDescriptor::withOptions(void *         buffers,
+                                UInt32         count,
+                                UInt32         offset,
+                                task_t         task,
+                                IOOptionBits   opts,
+                                IOMapper *     mapper)
 {
-    IOGeneralMemoryDescriptor * that = new IOGeneralMemoryDescriptor;
-    if (that)
-    {
-       if (that->initWithRanges(ranges, withCount, withDirection, withTask, asReference))
-           return that;
+    IOGeneralMemoryDescriptor *self = new IOGeneralMemoryDescriptor;
 
-        that->release();
+    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     withDirection,
-                                        bool            asReference = false)
+                                        IODirection     direction,
+                                        bool            asReference)
 {
     IOGeneralMemoryDescriptor * that = new IOGeneralMemoryDescriptor;
     if (that)
     {
-       if (that->initWithPhysicalRanges(ranges, withCount, withDirection, asReference))
+       if (that->initWithPhysicalRanges(ranges, withCount, direction, asReference))
            return that;
 
         that->release();
@@ -165,15 +436,96 @@ IOMemoryDescriptor *
 IOMemoryDescriptor::withSubRange(IOMemoryDescriptor *  of,
                                IOByteCount             offset,
                                IOByteCount             length,
-                               IODirection             withDirection)
+                               IODirection             direction)
 {
-    IOSubMemoryDescriptor * that = new IOSubMemoryDescriptor;
+    IOSubMemoryDescriptor *self = new IOSubMemoryDescriptor;
 
-    if (that && !that->initSubRange(of, offset, length, withDirection)) {
-        that->release();
-       that = 0;
+    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 that;
+
+    return MACH_PORT_NULL;
 }
 
 /*
@@ -223,29 +575,120 @@ IOGeneralMemoryDescriptor::initWithPhysicalAddress(
     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, 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 */ 0);
+}
+
 /*
- * initWithRanges:
+ * initWithOptions:
  *
- * Initialize an IOMemoryDescriptor. The buffer is made up of several
- * virtual address ranges, from a given task
+ *  IOMemoryDescriptor. The buffer is made up of several virtual address ranges,
+ * from a given task, several physical ranges, an UPL from the ubc
+ * system or a uio (may be 64bit) from the BSD subsystem.
  *
  * Passing the ranges as a reference will avoid an extra allocation.
  *
- * 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.
+ * An IOMemoryDescriptor can be re-used by calling initWithOptions 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::initWithRanges(
-                                   IOVirtualRange * ranges,
-                                   UInt32           withCount,
-                                   IODirection      withDirection,
-                                   task_t           withTask,
-                                   bool             asReference = false)
-{
-    assert(ranges);
-    assert(withCount);
+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
@@ -253,77 +696,170 @@ IOGeneralMemoryDescriptor::initWithRanges(
      * variables are zeroed on an object's allocation.
      */
 
-    if (_initialized == false)
-    {
-        if (super::init() == false)  return false;
-        _initialized = true;
-    }
-    else
-    {
+    if (_initialized) {
         /*
          * An existing memory descriptor is being retargeted to point to
          * somewhere else.  Clean up our present state.
          */
 
-        assert(_wireCount == 0);
-
         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;
     }
 
-    /*
-     * Initialize the memory descriptor.
-     */
+    // 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;
 
-    _ranges.v              = 0;
-    _rangesCount           = withCount;
-    _rangesIsAllocated     = asReference ? false : true;
-    _direction             = withDirection;
-    _length                = 0;
-    _task                  = withTask;
+    // DEPRECATED variable initialisation
+    _direction             = (IODirection) (_flags & kIOMemoryDirectionMask);
     _position              = 0;
-    _positionAtIndex       = 0;
-    _positionAtOffset      = 0;
     _kernPtrAligned        = 0;
     _cachedPhysicalAddress = 0;
     _cachedVirtualAddress  = 0;
-    _flags                = 0;
 
-    if (withTask && (withTask != kernel_task))
-        _flags |= kIOMemoryRequiresWire;
+    if (kIOMemoryTypeUPL == type) {
 
-    if (asReference)
-        _ranges.v = ranges;
-    else
-    {
-        _ranges.v = IONew(IOVirtualRange, withCount);
-        if (_ranges.v == 0)  return false;
-        bcopy(/* from */ ranges, _ranges.v, withCount * sizeof(IOVirtualRange));
-    } 
+        ioGMDData *dataP;
+        unsigned int dataSize = computeDataSize(/* pages */ 0, /* upls */ 1);
 
-    for (unsigned index = 0; index < _rangesCount; index++)
-    {
-        _length += _ranges.v[index].length;
+        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;
+       }
+       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;
 }
 
-bool
-IOGeneralMemoryDescriptor::initWithPhysicalRanges(     IOPhysicalRange * ranges,
-                                               UInt32           withCount,
-                                               IODirection      withDirection,
-                                               bool             asReference = false)
-{
-#warning assuming virtual, physical addresses same size
-    return( initWithRanges( (IOVirtualRange *) ranges,
-                       withCount, withDirection, (task_t) 0, asReference ));
-}
-
 /*
  * free
  *
@@ -331,98 +867,42 @@ IOGeneralMemoryDescriptor::initWithPhysicalRanges(        IOPhysicalRange * ranges,
  */
 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( _memEntry)
-        ipc_port_release_send( (ipc_port_t) _memEntry );
-    super::free();
-}
 
-void IOGeneralMemoryDescriptor::unmapFromKernel()
-{
-    kern_return_t krtn;
-    vm_offset_t off;
-    // Pull the shared pages out of the task map
-    // Do we need to unwire it first?
-    for ( off = 0; off < _kernSize; off += page_size )
-    {
-       pmap_change_wiring(
-                       kernel_pmap,
-                       _kernPtrAligned + off,
-                       FALSE);
-
-       pmap_remove(
-                       kernel_pmap,
-                       _kernPtrAligned + off,
-                       _kernPtrAligned + off + page_size);
-    }
-    // Free the former shmem area in the task
-    krtn = vm_deallocate(kernel_map,
-                       _kernPtrAligned,
-                       _kernSize );
-    assert(krtn == KERN_SUCCESS);
-    _kernPtrAligned = 0;
-}
+    if (reserved && reserved->devicePager)
+       device_pager_deallocate( (memory_object_t) reserved->devicePager );
 
-void IOGeneralMemoryDescriptor::mapIntoKernel(unsigned rangeIndex)
-{
-    kern_return_t krtn;
-    vm_offset_t off;
+    // 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 );
 
-    if (_kernPtrAligned)
-    {
-        if (_kernPtrAtIndex == rangeIndex)  return;
-        unmapFromKernel();
-        assert(_kernPtrAligned == 0);
-    }
-    vm_offset_t srcAlign = trunc_page(_ranges.v[rangeIndex].address);
-
-    _kernSize = trunc_page(_ranges.v[rangeIndex].address +
-                           _ranges.v[rangeIndex].length  +
-                           page_size - 1) - srcAlign;
-
-    /* Find some memory of the same size in kernel task.  We use vm_allocate()
-    to do this. vm_allocate inserts the found memory object in the
-    target task's map as a side effect. */
-    krtn = vm_allocate( kernel_map,
-           &_kernPtrAligned,
-           _kernSize,
-           VM_FLAGS_ANYWHERE|VM_MAKE_TAG(VM_MEMORY_IOKIT) );  // Find first fit
-    assert(krtn == KERN_SUCCESS);
-    if(krtn)  return;
-
-    /* For each page in the area allocated from the kernel map,
-           find the physical address of the page.
-           Enter the page in the target task's pmap, at the
-           appropriate target task virtual address. */
-    for ( off = 0; off < _kernSize; off += page_size )
-    {
-       vm_offset_t kern_phys_addr, phys_addr;
-       if( _task)
-           phys_addr = pmap_extract( get_task_pmap(_task), srcAlign + off );
-       else
-           phys_addr = srcAlign + off;
-        assert(phys_addr);
-       if(phys_addr == 0)  return;
-
-       // Check original state.
-       kern_phys_addr = pmap_extract( kernel_pmap, _kernPtrAligned + off );
-       // Set virtual page to point to the right physical one
-       pmap_enter(
-           kernel_pmap,
-           _kernPtrAligned + off,
-           phys_addr,
-           VM_PROT_READ|VM_PROT_WRITE,
-           TRUE);
-    }
-    _kernPtrAtIndex = rangeIndex;
+    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:
  *
@@ -443,8 +923,7 @@ IOByteCount IOMemoryDescriptor::getLength() const
     return _length;
 }
 
-void IOMemoryDescriptor::setTag(
-       IOOptionBits            tag )
+void IOMemoryDescriptor::setTag( IOOptionBits tag )
 {
     _tag = tag;    
 }
@@ -454,459 +933,736 @@ IOOptionBits IOMemoryDescriptor::getTag( void )
     return( _tag);
 }
 
-/*
- * setPosition
- *
- * Set the logical start position inside the client buffer.
- *
- * It is convention that the position reflect the actual byte count that
- * is successfully transferred into or out of the buffer, before the I/O
- * request is "completed" (ie. sent back to its originator).
- */
-
-void IOGeneralMemoryDescriptor::setPosition(IOByteCount position)
+// @@@ gvdl: who is using this API?  Seems like a wierd thing to implement.
+IOPhysicalAddress IOMemoryDescriptor::getSourceSegment( IOByteCount   offset,
+                                                        IOByteCount * length )
 {
-    assert(position <= _length);
+    IOPhysicalAddress physAddr = 0;
 
-    if (position >= _length)
-    {
-        _position         = _length;
-        _positionAtIndex  = _rangesCount;          /* careful: out-of-bounds */
-        _positionAtOffset = 0;
-        return;
-    }
-
-    if (position < _position)
-    {
-       _positionAtOffset = position;
-       _positionAtIndex  = 0;
-    }
-    else
-    {
-       _positionAtOffset += (position - _position);
+    if( prepare() == kIOReturnSuccess) {
+        physAddr = getPhysicalSegment( offset, length );
+        complete();
     }
-    _position = position;
 
-    while (_positionAtOffset >= _ranges.v[_positionAtIndex].length)
-    {
-        _positionAtOffset -= _ranges.v[_positionAtIndex].length;
-        _positionAtIndex++;
-    }
+    return( physAddr );
 }
 
-/*
- * readBytes:
- *
- * Copy data from the memory descriptor's buffer into the specified buffer,
- * relative to the current position.   The memory descriptor's position is
- * advanced based on the number of bytes copied.
- */
-
-IOByteCount IOGeneralMemoryDescriptor::readBytes(IOByteCount offset,
-                                       void * bytes, IOByteCount withLength)
+IOByteCount IOMemoryDescriptor::readBytes
+                (IOByteCount offset, void *bytes, IOByteCount length)
 {
-    IOByteCount bytesLeft;
-    void *    segment;
-    IOByteCount segmentLength;
+    addr64_t dstAddr = (addr64_t) (UInt32) bytes;
+    IOByteCount remaining;
 
-    if( offset != _position)
-       setPosition( offset );
+    // 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;
+    }
 
-    withLength = min(withLength, _length - _position);
-    bytesLeft  = withLength;
+    remaining = length = min(length, _length - offset);
+    while (remaining) {        // (process another target segment?)
+        addr64_t       srcAddr64;
+        IOByteCount    srcLen;
 
-#if 0
-    while (bytesLeft && (_position < _length))
-    {
-       /* Compute the relative length to the end of this virtual segment. */
-        segmentLength = min(_ranges.v[_positionAtIndex].length - _positionAtOffset, bytesLeft);
+        srcAddr64 = getPhysicalSegment64(offset, &srcLen);
+        if (!srcAddr64)
+            break;
 
-       /* Compute the relative address of this virtual segment. */
-        segment = (void *)(_ranges.v[_positionAtIndex].address + _positionAtOffset);
+        // Clip segment length to remaining
+        if (srcLen > remaining)
+            srcLen = remaining;
 
-       if (KERN_SUCCESS != vm_map_read_user(getMapForTask(_task, segment),
-               /* from */ (vm_offset_t) segment, /* to */ (vm_offset_t) bytes,
-               /* size */ segmentLength))
-       {
-           assert( false );
-            bytesLeft = withLength;
-           break;
-       }
-        bytesLeft -= segmentLength;
-       offset += segmentLength;
-       setPosition(offset);
-    }
-#else
-    while (bytesLeft && (segment = getVirtualSegment(offset, &segmentLength)))
-    {
-        segmentLength = min(segmentLength, bytesLeft);
-        bcopy(/* from */ segment, /* to */ bytes, /* size */ segmentLength);
-        bytesLeft -= segmentLength;
-       offset += segmentLength;
-        bytes = (void *) (((UInt32) bytes) + segmentLength);
+        copypv(srcAddr64, dstAddr, srcLen,
+                            cppvPsrc | cppvNoRefSrc | cppvFsnk | cppvKmap);
+
+        dstAddr   += srcLen;
+        offset    += srcLen;
+        remaining -= srcLen;
     }
-#endif
 
-    return withLength - bytesLeft;
+    assert(!remaining);
+
+    return length - remaining;
 }
 
-/*
- * writeBytes:
- *
- * Copy data to the memory descriptor's buffer from the specified buffer,
- * relative to the current position.  The memory descriptor's position is
- * advanced based on the number of bytes copied.
- */
-IOByteCount IOGeneralMemoryDescriptor::writeBytes(IOByteCount offset,
-                               const void* bytes,IOByteCount withLength)
+IOByteCount IOMemoryDescriptor::writeBytes
+                (IOByteCount offset, const void *bytes, IOByteCount length)
 {
-    IOByteCount bytesLeft;
-    void *    segment;
-    IOByteCount segmentLength;
+    addr64_t srcAddr = (addr64_t) (UInt32) bytes;
+    IOByteCount remaining;
 
-    if( offset != _position)
-       setPosition( offset );
+    // Assert that this entire I/O is withing the available range
+    assert(offset < _length);
+    assert(offset + length <= _length);
 
-    withLength = min(withLength, _length - _position);
-    bytesLeft  = withLength;
+    assert( !(kIOMemoryPreparedReadOnly & _flags) );
 
-#if 0
-    while (bytesLeft && (_position < _length))
-    {
-       assert(_position <= _length);
+    if ( (kIOMemoryPreparedReadOnly & _flags) || offset >= _length) {
+IOLog("IOGMD(%p): wB = o%lx, l%lx\n", this, offset, length);   // @@@ gvdl
+        return 0;
+    }
 
-       /* Compute the relative length to the end of this virtual segment. */
-        segmentLength = min(_ranges.v[_positionAtIndex].length - _positionAtOffset, bytesLeft);
+    remaining = length = min(length, _length - offset);
+    while (remaining) {        // (process another target segment?)
+        addr64_t    dstAddr64;
+        IOByteCount dstLen;
 
-       /* Compute the relative address of this virtual segment. */
-        segment = (void *)(_ranges.v[_positionAtIndex].address + _positionAtOffset);
+        dstAddr64 = getPhysicalSegment64(offset, &dstLen);
+        if (!dstAddr64)
+            break;
 
-       if (KERN_SUCCESS != vm_map_write_user(getMapForTask(_task, segment),
-               /* from */ (vm_offset_t) bytes, 
-               /* to */ (vm_offset_t) segment,
-               /* size */ segmentLength))
-       {
-           assert( false );
-            bytesLeft = withLength;
-           break;
-       }
-        bytesLeft -= segmentLength;
-       offset += segmentLength;
-       setPosition(offset);
+        // 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;
     }
-#else
-    while (bytesLeft && (segment = getVirtualSegment(offset, &segmentLength)))
+
+    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?)
     {
-        segmentLength = min(segmentLength, bytesLeft);
-        bcopy(/* from */ bytes, /* to */ segment, /* size */ segmentLength);
-        // Flush cache in case we're copying code around, eg. handling a code page fault
-        IOFlushProcessorCache(kernel_task, (vm_offset_t) segment, segmentLength );
+        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];
         
-        bytesLeft -= segmentLength;
-        offset += segmentLength;
-        bytes = (void *) (((UInt32) bytes) + segmentLength);
+                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;
     }
-#endif
 
-    return withLength - bytesLeft;
+    if (lengthOfSegment)
+        *lengthOfSegment = length;
+
+    return address;
 }
 
-/*
- * getPhysicalSegment:
- *
- * Get the physical address of the buffer, relative to the current position.
- * If the current position is at the end of the buffer, a zero is returned.
- */
-IOPhysicalAddress
-IOGeneralMemoryDescriptor::getPhysicalSegment(IOByteCount offset,
-                                               IOByteCount * lengthOfSegment)
+addr64_t IOMemoryDescriptor::getPhysicalSegment64
+                        (IOByteCount offset, IOByteCount *lengthOfSegment)
 {
-    vm_address_t      virtualAddress;
-    IOByteCount       virtualLength;
-    pmap_t            virtualPMap;
-    IOPhysicalAddress physicalAddress;
-    IOPhysicalLength  physicalLength;
+    IOPhysicalAddress phys32;
+    IOByteCount              length;
+    addr64_t         phys64;
 
-    if( kIOMemoryRequiresWire & _flags)
-        assert( _wireCount );
+    phys32 = getPhysicalSegment(offset, lengthOfSegment);
+    if (!phys32)
+       return 0;
 
-    if ((0 == _task) && (1 == _rangesCount))
+    if (gIOSystemMapper)
     {
-       assert(offset <= _length);
-       if (offset >= _length)
-       {
-           physicalAddress = 0;
-           physicalLength  = 0;
-       }
-       else
-       {
-           physicalLength = _length - offset;
-           physicalAddress = offset + _ranges.v[0].address;
-       }
-
-       if (lengthOfSegment)
-           *lengthOfSegment = physicalLength;
-       return physicalAddress;
+       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;
+}
 
-    if( offset != _position)
-       setPosition( offset );
+IOPhysicalAddress IOGeneralMemoryDescriptor::
+getSourceSegment(IOByteCount offset, IOByteCount *lengthOfSegment)
+{
+    IOPhysicalAddress address = 0;
+    IOPhysicalLength  length  = 0;
+    IOOptionBits      type    = _flags & kIOMemoryTypeMask;
 
-    assert(_position <= _length);
+    assert(offset <= _length);
 
-    /* Fail gracefully if the position is at (or past) the end-of-buffer. */
-    if (_position >= _length)
+    if ( type == kIOMemoryTypeUPL)
+       return super::getSourceSegment( offset, lengthOfSegment );
+    else if ( offset < _length ) // (within bounds?)
     {
-        *lengthOfSegment = 0;
-        return 0;
+        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;
     }
 
-    /* Prepare to compute the largest contiguous physical length possible. */
+    if ( lengthOfSegment )  *lengthOfSegment = length;
 
-    virtualAddress  = _ranges.v[_positionAtIndex].address + _positionAtOffset;
-    virtualLength   = _ranges.v[_positionAtIndex].length  - _positionAtOffset;
-    vm_address_t      virtualPage  = trunc_page(virtualAddress);
-    if( _task)
-       virtualPMap     = get_task_pmap(_task);
-    else
-       virtualPMap     = 0;
+    return address;
+}
 
-    physicalAddress = (virtualAddress == _cachedVirtualAddress) ?
-                        _cachedPhysicalAddress :              /* optimization */
-                       virtualPMap ?
-                               pmap_extract(virtualPMap, virtualAddress) :
-                               virtualAddress;
-    physicalLength  = trunc_page(physicalAddress) + page_size - physicalAddress;
+/* 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");
 
-    if (!physicalAddress && _task)
-    {
-       physicalAddress =
-           vm_map_get_phys_page(get_task_map(_task), virtualPage);
-       physicalAddress += virtualAddress - virtualPage;
-    }
+                    return 0;
+/* DEPRECATED */ }
+/* DEPRECATED */ /* USE INSTEAD: map(), readBytes(), writeBytes() */
 
-    if (physicalAddress == 0)     /* memory must be wired in order to proceed */
-    {
-        assert(physicalAddress);
-        *lengthOfSegment = 0;
-        return 0;
-    }
 
-    /* Compute the largest contiguous physical length possible, within range. */
-    IOPhysicalAddress physicalPage = trunc_page(physicalAddress);
 
-    while (physicalLength < virtualLength)
+IOReturn IOMemoryDescriptor::setPurgeable( IOOptionBits newState,
+                                           IOOptionBits * oldState )
+{
+    IOReturn     err = kIOReturnSuccess;
+    vm_purgable_t control;
+    int           state;
+
+    do 
     {
-        physicalPage          += page_size;
-        virtualPage           += page_size;
-        _cachedVirtualAddress  = virtualPage;
-        _cachedPhysicalAddress = virtualPMap ?
-                                       pmap_extract(virtualPMap, virtualPage) :
-                                       virtualPage;
-       if (!_cachedPhysicalAddress && _task)
-       {
-           _cachedPhysicalAddress =
-               vm_map_get_phys_page(get_task_map(_task), virtualPage);
-       }
+        if (!_memEntry)
+        {
+            err = kIOReturnNotReady;
+            break;
+        }
 
-        if (_cachedPhysicalAddress != physicalPage)  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;
+        }
 
-        physicalLength += page_size;
-    }
+        if (kIOReturnSuccess != err)
+            break;
 
-    /* Clip contiguous physical length at the end of this range. */
-    if (physicalLength > virtualLength)
-        physicalLength = virtualLength;
+        err = mach_memory_entry_purgable_control((ipc_port_t) _memEntry, control, &state);
 
-    if( lengthOfSegment)
-       *lengthOfSegment = physicalLength;
+        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 physicalAddress;
+    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);
 
-/*
- * getVirtualSegment:
- *
- * Get the virtual address of the buffer, relative to the current position.
- * If the memory wasn't mapped into the caller's address space, it will be
- * mapped in now.   If the current position is at the end of the buffer, a
- * null is returned.
- */
-void * IOGeneralMemoryDescriptor::getVirtualSegment(IOByteCount offset,
-                                                       IOByteCount * lengthOfSegment)
+IOReturn IOMemoryDescriptor::performOperation( IOOptionBits options,
+                                                IOByteCount offset, IOByteCount length )
 {
-    if( offset != _position)
-       setPosition( offset );
-
-    assert(_position <= _length);
+    IOByteCount remaining;
+    void (*func)(addr64_t pa, unsigned int count) = 0;
 
-    /* Fail gracefully if the position is at (or past) the end-of-buffer. */
-    if (_position >= _length)
+    switch (options)
     {
-        *lengthOfSegment = 0;
-        return 0;
+        case kIOMemoryIncoherentIOFlush:
+            func = &dcache_incoherent_io_flush64;
+            break;
+        case kIOMemoryIncoherentIOStore:
+            func = &dcache_incoherent_io_store64;
+            break;
     }
 
-    /* Compute the relative length to the end of this virtual segment. */
-    *lengthOfSegment = _ranges.v[_positionAtIndex].length - _positionAtOffset;
+    if (!func)
+        return (kIOReturnUnsupported);
 
-    /* Compute the relative address of this virtual segment. */
-    if (_task == kernel_task)
-        return (void *)(_ranges.v[_positionAtIndex].address + _positionAtOffset);
-    else
+    remaining = length = min(length, getLength() - offset);
+    while (remaining)
+    // (process another target segment?)
     {
-       vm_offset_t off;
+        addr64_t    dstAddr64;
+        IOByteCount dstLen;
+
+        dstAddr64 = getPhysicalSegment64(offset, &dstLen);
+        if (!dstAddr64)
+            break;
 
-        mapIntoKernel(_positionAtIndex);
+        // Clip segment length to remaining
+        if (dstLen > remaining)
+            dstLen = remaining;
 
-       off  = _ranges.v[_kernPtrAtIndex].address;
-       off -= trunc_page(off);
+       (*func)(dstAddr64, dstLen);
 
-       return (void *) (_kernPtrAligned + off + _positionAtOffset);
+        offset    += dstLen;
+        remaining -= dstLen;
     }
+
+    return (remaining ? kIOReturnUnderrun : kIOReturnSuccess);
 }
 
-/*
- * prepare
- *
- * Prepare the memory for an I/O transfer.  This involves paging in
- * the memory, if necessary, and wiring it down for the duration of
- * the transfer.  The complete() method completes the processing of
- * the memory after the I/O transfer finishes.  This method needn't
- * called for non-pageable memory.
- */
-IOReturn IOGeneralMemoryDescriptor::prepare(
-               IODirection forDirection = kIODirectionNone)
+#ifdef __ppc__
+extern vm_offset_t             static_memory_end;
+#define io_kernel_static_end   static_memory_end
+#else
+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 */,
+       vm_address_t            offset,
+       vm_size_t               *upl_size,
+       upl_t                   *upl,
+       upl_page_info_array_t   page_list,
+       unsigned int            *count)
 {
-    UInt rangeIndex = 0;
+    unsigned int pageCount, page;
+    ppnum_t phys;
 
-    if((_wireCount == 0) && (kIOMemoryRequiresWire & _flags)) {
-        kern_return_t rc;
+    pageCount = atop_32(*upl_size);
+    if (pageCount > *count)
+       pageCount = *count;
 
-        if(forDirection == kIODirectionNone)
-            forDirection = _direction;
+    *upl = NULL;
 
-        vm_prot_t access = VM_PROT_DEFAULT;    // Could be cleverer using direction
+    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;
+    }
 
-        //
-        // Check user read/write access to the data buffer.
-        //
+    return ((page >= pageCount) ? kIOReturnSuccess : kIOReturnVMError);
+}
 
-        for (rangeIndex = 0; rangeIndex < _rangesCount; rangeIndex++)
-        {
-            vm_offset_t checkBase = trunc_page(_ranges.v[rangeIndex].address);
-            vm_size_t   checkSize = round_page(_ranges.v[rangeIndex].length );
+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;
 
-            while (checkSize)
-            {
-                vm_region_basic_info_data_t regionInfo;
-                mach_msg_type_number_t      regionInfoSize = sizeof(regionInfo);
-                vm_size_t                   regionSize;
-
-                if ( (vm_region(
-                          /* map         */ getMapForTask(_task, checkBase),
-                          /* address     */ &checkBase,
-                          /* size        */ &regionSize,
-                          /* flavor      */ VM_REGION_BASIC_INFO,
-                          /* info        */ (vm_region_info_t) &regionInfo,
-                          /* info size   */ &regionInfoSize,
-                          /* object name */ 0 ) != KERN_SUCCESS             ) ||
-                     ( (forDirection & kIODirectionIn ) &&
-                                   !(regionInfo.protection & VM_PROT_WRITE) ) ||
-                     ( (forDirection & kIODirectionOut) && 
-                                   !(regionInfo.protection & VM_PROT_READ ) ) )
-                {
-                    return kIOReturnVMError;
-                }
+    assert(!_wireCount);
+    assert(kIOMemoryTypeVirtual == type || kIOMemoryTypeUIO == type);
 
-                assert((regionSize & PAGE_MASK) == 0);
+    if (_pages >= gIOMaximumMappedIOPageCount)
+       return kIOReturnNoResources;
 
-                regionSize = min(regionSize, checkSize);
-                checkSize -= regionSize;
-                checkBase += regionSize;
-            } // (for each vm region)
-        } // (for each io range)
+    dataP = getDataP(_memoryEntries);
+    mapper = dataP->fMapper;
+    if (mapper && _pages)
+        mapBase = mapper->iovmAlloc(_pages);
 
-        for (rangeIndex = 0; rangeIndex < _rangesCount; rangeIndex++) {
+    // 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.
 
-            vm_offset_t srcAlign = trunc_page(_ranges.v[rangeIndex].address);
-            IOByteCount srcAlignEnd = trunc_page(_ranges.v[rangeIndex].address +
-                                _ranges.v[rangeIndex].length  +
-                                page_size - 1);
+    if (forDirection == kIODirectionNone)
+        forDirection = _direction;
 
-           vm_map_t taskVMMap = getMapForTask(_task, srcAlign);
+    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;
 
-            rc = vm_map_wire(taskVMMap, srcAlign, srcAlignEnd, access, FALSE);
-           if (KERN_SUCCESS != rc) {
-               IOLog("IOMemoryDescriptor::prepare vm_map_wire failed: %d\n", rc);
-               goto abortExit;
+    // 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 this I/O is for a user land task then protect ourselves
-           // against COW and other vm_shenanigans
-           if (_task && _task != kernel_task) {
-               // setup a data object to hold the 'named' memory regions
-               // @@@ gvdl: If we fail to allocate an OSData we will just
-               // hope for the best for the time being.  Lets not fail a
-               // prepare at this late stage in product release.
-               if (!_memoryEntries)
-                   _memoryEntries = OSData::withCapacity(16);
-               if (_memoryEntries) {
-                   vm_object_offset_t desiredSize = srcAlignEnd - srcAlign;
-                   vm_object_offset_t entryStart = srcAlign;
-                   ipc_port_t memHandle;
-
-                   do {
-                       vm_object_offset_t actualSize = desiredSize;
-
-                       rc = mach_make_memory_entry_64
-                           (taskVMMap, &actualSize, entryStart,
-                           forDirection, &memHandle, NULL);
-                       if (KERN_SUCCESS != rc) {
-                           IOLog("IOMemoryDescriptor::prepare mach_make_memory_entry_64 failed: %d\n", rc);
-                           goto abortExit;
-                       }
-
-                       _memoryEntries->
-                           appendBytes(&memHandle, sizeof(memHandle));
-                       desiredSize -= actualSize;
-                       entryStart += actualSize;
-                   } while (desiredSize);
+            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;
+            }
         }
     }
-    _wireCount++;
+
     return kIOReturnSuccess;
 
 abortExit:
-    UInt doneIndex;
-
-
-    for(doneIndex = 0; doneIndex < rangeIndex; doneIndex++) {
-       vm_offset_t srcAlign = trunc_page(_ranges.v[doneIndex].address);
-       IOByteCount srcAlignEnd = trunc_page(_ranges.v[doneIndex].address +
-                           _ranges.v[doneIndex].length  +
-                           page_size - 1);
+    {
+        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);
+           }
+       }
+       (void) _memoryEntries->initWithBytes(dataP, sizeof(ioGMDData)); // == setLength()
 
-       vm_map_unwire(getMapForTask(_task, srcAlign), srcAlign,
-                           srcAlignEnd, FALSE);
+        if (mapper && mapBase)
+            mapper->iovmFree(mapBase, _pages);
     }
 
-    if (_memoryEntries) {
-       ipc_port_t *handles, *handlesEnd;
+    return error;
+}
+
+/*
+ * prepare
+ *
+ * Prepare the memory for an I/O transfer.  This involves paging in
+ * the memory, if necessary, and wiring it down for the duration of
+ * the transfer.  The complete() method completes the processing of
+ * 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;
 
-       handles = (ipc_port_t *) _memoryEntries->getBytesNoCopy();
-       handlesEnd = (ipc_port_t *)
-           ((vm_address_t) handles + _memoryEntries->getLength());
-       while (handles < handlesEnd)
-           ipc_port_release_send(*handles++);
-       _memoryEntries->release();
-       _memoryEntries = 0;
+    if (!_wireCount
+    && (kIOMemoryTypeVirtual == type || kIOMemoryTypeUIO == type) ) {
+        error = wireVirtual(forDirection);
+        if (error)
+            return error;
     }
 
-    return kIOReturnVMError;
+    _wireCount++;
+
+    return kIOReturnSuccess;
 }
 
 /*
@@ -918,52 +1674,40 @@ abortExit:
  * before and after an I/O transfer involving pageable memory.
  */
  
-IOReturn IOGeneralMemoryDescriptor::complete(
-               IODirection forDirection = kIODirectionNone)
+IOReturn IOGeneralMemoryDescriptor::complete(IODirection /* forDirection */)
 {
     assert(_wireCount);
 
-    if(0 == _wireCount)
+    if (!_wireCount)
         return kIOReturnSuccess;
 
     _wireCount--;
-    if((_wireCount == 0) && (kIOMemoryRequiresWire & _flags)) {
-        UInt rangeIndex;
-        kern_return_t rc;
+    if (!_wireCount) {
+       IOOptionBits type = _flags & kIOMemoryTypeMask;
 
-        if(forDirection == kIODirectionNone)
-            forDirection = _direction;
-
-        for(rangeIndex = 0; rangeIndex < _rangesCount; rangeIndex++) {
-
-            vm_offset_t srcAlign = trunc_page(_ranges.v[rangeIndex].address);
-            IOByteCount srcAlignEnd = trunc_page(_ranges.v[rangeIndex].address +
-                                _ranges.v[rangeIndex].length  +
-                                page_size - 1);
-
-            if(forDirection == kIODirectionIn)
-                pmap_modify_pages(get_task_pmap(_task), srcAlign, srcAlignEnd);
-
-            rc = vm_map_unwire(getMapForTask(_task, srcAlign), srcAlign,
-                                  srcAlignEnd, FALSE);
-            if(rc != KERN_SUCCESS)
-                IOLog("IOMemoryDescriptor::complete: vm_map_unwire failed: %d\n", rc);
+        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);
+                   }
+            }
 
-       if (_memoryEntries) {
-           ipc_port_t *handles, *handlesEnd;
-
-           handles = (ipc_port_t *) _memoryEntries->getBytesNoCopy();
-           handlesEnd = (ipc_port_t *)
-                       ((vm_address_t) handles + _memoryEntries->getLength());
-           while (handles < handlesEnd)
-               ipc_port_release_send(*handles++);
-
-           _memoryEntries->release();
-           _memoryEntries = 0;
-       }
-
-       _cachedVirtualAddress = 0;
+            (void) _memoryEntries->initWithBytes(dataP, sizeof(ioGMDData)); // == setLength()
+        }
     }
     return kIOReturnSuccess;
 }
@@ -972,66 +1716,142 @@ IOReturn IOGeneralMemoryDescriptor::doMap(
        vm_map_t                addressMap,
        IOVirtualAddress *      atAddress,
        IOOptionBits            options,
-       IOByteCount             sourceOffset = 0,
-       IOByteCount             length = 0 )
+       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)
-       && (length <= _ranges.v[0].length) ) {
-           *atAddress = _ranges.v[0].address;
+    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 );
+       }
     }
 
-     if( _task && _memEntry && (_flags & kIOMemoryRequiresWire)) {
+    if( 0 == sharedMem) {
 
-        do {
+        vm_size_t size = ptoa_32(_pages);
 
-            if( (1 != _rangesCount)
-             || (kIOMapDefaultCache != (options & kIOMapCacheMask)) ) {
-                kr = kIOReturnUnsupported;
-                continue;
+        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( 0 == length)
-                length = getLength();
-            if( (sourceOffset + length) > _ranges.v[0].length) {
-                kr = kIOReturnBadArgument;
-                continue;
+            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;
 
-            ipc_port_t sharedMem = (ipc_port_t) _memEntry;
-            vm_prot_t prot = VM_PROT_READ
-                            | ((options & kIOMapReadOnly) ? 0 : VM_PROT_WRITE);
+           /*What cache mode do we need*/
+            switch(options & kIOMapCacheMask ) {
 
-            // vm_map looks for addresses above here, even when VM_FLAGS_ANYWHERE
-            if( options & kIOMapAnywhere)
-                *atAddress = 0;
+               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;
+           }
 
-            if( 0 == sharedMem)
-                kr = kIOReturnVMError;
-            else
-                kr = KERN_SUCCESS;
-
-            if( KERN_SUCCESS == kr)
-                kr = vm_map( addressMap,
-                             atAddress,
-                             length, 0 /* mask */, 
-                             (( options & kIOMapAnywhere ) ? VM_FLAGS_ANYWHERE : VM_FLAGS_FIXED)
-                             | VM_MAKE_TAG(VM_MEMORY_IOKIT), 
-                             sharedMem, sourceOffset,
-                             false, // copy
-                             prot, // cur
-                             prot, // max
-                             VM_INHERIT_NONE);
-        
         } while( false );
 
-    } else
-        kr = super::doMap( addressMap, atAddress,
+        _memEntry = (void *) sharedMem;
+    }
+
+
+#ifndef i386
+    if( 0 == sharedMem)
+      kr = kIOReturnVMError;
+    else
+#endif
+      kr = super::doMap( addressMap, atAddress,
                            options, sourceOffset, length );
+
     return( kr );
 }
 
@@ -1041,90 +1861,28 @@ IOReturn IOGeneralMemoryDescriptor::doUnmap(
        IOByteCount             length )
 {
     // could be much better
-    if( _task && (addressMap == getMapForTask(_task, _ranges.v[0].address)) && (1 == _rangesCount)
-        && (logical == _ranges.v[0].address)
-        && (length <= _ranges.v[0].length) )
+    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 ));
 }
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-extern "C" {
-// osfmk/device/iokit_rpc.c
-extern kern_return_t IOMapPages( vm_map_t map, vm_offset_t va, vm_offset_t pa,
-                                 vm_size_t length, unsigned int mapFlags);
-};
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-static IORecursiveLock * gIOMemoryLock;
-
-#define LOCK   IORecursiveLockLock( gIOMemoryLock)
-#define UNLOCK IORecursiveLockUnlock( gIOMemoryLock)
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-OSDefineMetaClass( IOMemoryMap, OSObject )
-OSDefineAbstractStructors( IOMemoryMap, OSObject )
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-class _IOMemoryMap : public IOMemoryMap
-{
-    OSDeclareDefaultStructors(_IOMemoryMap)
-
-    IOMemoryDescriptor * memory;
-    IOMemoryMap *      superMap;
-    IOByteCount                offset;
-    IOByteCount                length;
-    IOVirtualAddress   logical;
-    task_t             addressTask;
-    vm_map_t           addressMap;
-    IOOptionBits       options;
-
-public:
-    virtual void free();
-
-    // 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 IOPhysicalAddress  getPhysicalSegment(IOByteCount offset,
-                                                  IOByteCount * length);
-
-    // for IOMemoryDescriptor use
-    _IOMemoryMap * isCompatible(
-               IOMemoryDescriptor *    owner,
-                task_t                 intoTask,
-                IOVirtualAddress       toAddress,
-                IOOptionBits           options,
-                IOByteCount            offset,
-                IOByteCount            length );
-
-    bool init(
-       IOMemoryDescriptor *    memory,
-       IOMemoryMap *           superMap,
-        IOByteCount            offset,
-        IOByteCount            length );
+OSDefineMetaClassAndAbstractStructors( IOMemoryMap, OSObject )
 
-    bool init(
-       IOMemoryDescriptor *    memory,
-       task_t                  intoTask,
-       IOVirtualAddress        toAddress,
-       IOOptionBits            options,
-        IOByteCount            offset,
-        IOByteCount            length );
-};
+/* inline function implementation */
+IOPhysicalAddress IOMemoryMap::getPhysicalAddress()
+    { return( getPhysicalSegment( 0, 0 )); }
 
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
 #undef super
 #define super IOMemoryMap
@@ -1133,7 +1891,7 @@ OSDefineMetaClassAndStructors(_IOMemoryMap, IOMemoryMap)
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-bool _IOMemoryMap::init(
+bool _IOMemoryMap::initCompatible(
        IOMemoryDescriptor *    _memory,
        IOMemoryMap *           _superMap,
         IOByteCount            _offset,
@@ -1163,7 +1921,7 @@ bool _IOMemoryMap::init(
     return( true );
 }
 
-bool _IOMemoryMap::init(
+bool _IOMemoryMap::initWithDescriptor(
         IOMemoryDescriptor *   _memory,
         task_t                 intoTask,
         IOVirtualAddress       toAddress,
@@ -1171,21 +1929,29 @@ bool _IOMemoryMap::init(
         IOByteCount            _offset,
         IOByteCount            _length )
 {
-    bool       ok;
+    bool ok;
+    bool redir = ((kIOMapUnique|kIOMapReference) == ((kIOMapUnique|kIOMapReference) & _options));
 
-    if( (!_memory) || (!intoTask) || !super::init())
+    if ((!_memory) || (!intoTask))
        return( false);
 
     if( (_offset + _length) > _memory->getLength())
        return( false);
 
-    addressMap  = get_task_map(intoTask);
-    if( !addressMap)
-       return( false);
-    kernel_vm_map_reference(addressMap);
+    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();
-    memory     = _memory;
 
     offset     = _offset;
     if( _length)
@@ -1193,116 +1959,377 @@ bool _IOMemoryMap::init(
     else
         length = _memory->getLength();
 
-    addressTask        = intoTask;
-    logical    = toAddress;
-    options    = _options;
-
     if( options & kIOMapStatic)
        ok = true;
     else
-       ok = (kIOReturnSuccess == memory->doMap( addressMap, &logical,
-                                                options, offset, length ));
-    if( !ok) {
-       logical = 0;
+       ok = (kIOReturnSuccess == _memory->doMap( addressMap, &toAddress,
+                                                 _options, offset, length ));
+    if (ok || redir)
+    {
+       if (memory)
+           memory->release();
+       memory  = _memory;
+       logical = toAddress;
+    }
+    else
+    {
         _memory->release();
-        vm_map_deallocate(addressMap);
-        addressMap = 0;
+       if (!redir)
+       {
+           logical = 0;
+           memory = 0;
+           vm_map_deallocate(addressMap);
+           addressMap = 0;
+       }
     }
+
     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 = 0,
-       IOByteCount             length = 0 )
+       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;
+           }
+       }
+       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;
+               }
+           }
+    
+           if( ref.sharedMem && (addressMap == kernel_map) && (kIOMemoryBufferPageable & _flags))
+               err = IOIteratePageableMaps( ref.size, &IOMemoryDescriptorMapAlloc, &ref );
+           else
+               err = IOMemoryDescriptorMapAlloc( addressMap, &ref );
+       }
+
+        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;
-    vm_size_t          ourSize;
+    memory_object_t    pager = (memory_object_t) _pager;
+    vm_size_t          size;
     vm_size_t          bytes;
-    vm_offset_t                mapped;
-    vm_address_t       logical;
+    vm_size_t          page;
     IOByteCount                pageOffset;
+    IOByteCount                pagerOffset;
     IOPhysicalLength   segLen;
-    IOPhysicalAddress  physAddr;
-
-    if( 0 == length)
-       length = getLength();
-
-    physAddr = getPhysicalSegment( sourceOffset, &segLen );
-    assert( physAddr );
+    addr64_t           physAddr;
 
-    pageOffset = physAddr - trunc_page( physAddr );
-    ourSize = length + pageOffset;
-    physAddr -= pageOffset;
-
-    logical = *atAddress;
-    if( 0 == (options & kIOMapAnywhere)) {
-        mapped = trunc_page( logical );
-       if( (logical - mapped) != pageOffset)
-           err = kIOReturnVMError;
-    }
-    if( kIOReturnSuccess == err)
-        err = vm_allocate( addressMap, &mapped, ourSize,
-                          ((options & kIOMapAnywhere) ? VM_FLAGS_ANYWHERE : VM_FLAGS_FIXED)
-                           | VM_MAKE_TAG(VM_MEMORY_IOKIT) );
+    if( !addressMap) {
 
-    if( err) {
+        if( kIOMemoryRedirected & _flags) {
 #ifdef DEBUG
-        kprintf("IOMemoryDescriptor::doMap: vm_allocate() "
-               "returned %08x\n", err);
+            IOLog("sleep mem redirect %p, %lx\n", this, sourceOffset);
 #endif
-        return( err);
-    }
+            do {
+               SLEEP;
+            } while( kIOMemoryRedirected & _flags );
+        }
 
-    // we have to make sure that these guys don't get copied if we fork.
-    err = vm_inherit( addressMap, mapped, ourSize, VM_INHERIT_NONE);
-    if( err != KERN_SUCCESS) {
-        doUnmap( addressMap, mapped, ourSize); // back out
-        return( err);
+        return( kIOReturnSuccess );
     }
 
-    logical = mapped;
-    *atAddress = mapped + pageOffset;
+    physAddr = getPhysicalSegment64( sourceOffset, &segLen );
+    assert( physAddr );
+    pageOffset = physAddr - trunc_page_64( physAddr );
+    pagerOffset = sourceOffset;
+
+    size = length + pageOffset;
+    physAddr -= pageOffset;
 
     segLen += pageOffset;
-    bytes = ourSize;
+    bytes = size;
     do {
        // in the middle of the loop only map whole pages
        if( segLen >= bytes)
            segLen = bytes;
-       else if( segLen != trunc_page( segLen))
+       else if( segLen != trunc_page_32( segLen))
            err = kIOReturnVMError;
-        if( physAddr != trunc_page( physAddr))
+        if( physAddr != trunc_page_64( physAddr))
            err = kIOReturnBadArgument;
 
 #ifdef DEBUG
        if( kIOLogMapping & gIOKitDebug)
-           kprintf("_IOMemoryMap::map(%x) %08x->%08x:%08x\n",
-                addressMap, mapped + pageOffset, physAddr + pageOffset,
+           IOLog("_IOMemoryMap::map(%p) %08lx->%08qx:%08lx\n",
+                addressMap, address + pageOffset, physAddr + pageOffset,
                segLen - pageOffset);
 #endif
 
-       if( kIOReturnSuccess == err)
-            err = IOMapPages( addressMap, mapped, physAddr, segLen, options );
+
+
+
+
+#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);
+       }
+
+       /*  *** Temporary Workaround *** */
+       /*  *** ALERT *** */
+#endif
        sourceOffset += segLen - pageOffset;
-       mapped += segLen;
+       address += segLen;
        bytes -= segLen;
        pageOffset = 0;
 
     } while( bytes
-       && (physAddr = getPhysicalSegment( sourceOffset, &segLen )));
+       && (physAddr = getPhysicalSegment64( sourceOffset, &segLen )));
 
     if( bytes)
         err = kIOReturnBadArgument;
-    if( err)
-       doUnmap( addressMap, logical, ourSize );
-    else
-        mapped = true;
 
     return( err );
 }
@@ -1320,14 +2347,101 @@ IOReturn IOMemoryDescriptor::doUnmap(
                 addressMap, logical, length );
 #endif
 
-    if( (addressMap == kernel_map) || (addressMap == get_task_map(current_task())))
+    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
+
+    } 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();
+       }
+    } 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
+        }
+        UNLOCK;
+    }
+
+    if (((memory->_flags & kIOMemoryTypeMask) == kIOMemoryTypePhysical) 
+     && safeTask
+     && (doRedirect != (0 != (memory->_flags & kIOMemoryRedirected))))
+       memory->redirect(safeTask, doRedirect);
+
+    return( err );
+}
+
 IOReturn _IOMemoryMap::unmap( void )
 {
     IOReturn   err;
@@ -1363,6 +2477,17 @@ void _IOMemoryMap::taskDied( void )
     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
+{
+    LOCK;
+    super::taggedRelease(tag, 2);
+    UNLOCK;
+}
+
 void _IOMemoryMap::free()
 {
     unmap();
@@ -1374,9 +2499,21 @@ void _IOMemoryMap::free()
        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();
 }
 
@@ -1408,7 +2545,7 @@ IOMemoryDescriptor * _IOMemoryMap::getMemoryDescriptor()
     return( memory );
 }
 
-_IOMemoryMap * _IOMemoryMap::isCompatible(
+_IOMemoryMap * _IOMemoryMap::copyCompatible(
                IOMemoryDescriptor *    owner,
                 task_t                 task,
                 IOVirtualAddress       toAddress,
@@ -1418,9 +2555,14 @@ _IOMemoryMap * _IOMemoryMap::isCompatible(
 {
     _IOMemoryMap * mapping;
 
-    if( (!task) || (task != getAddressTask()))
+    if( (!task) || (!addressMap) || (addressMap != get_task_map(task)))
+       return( 0 );
+    if( options & kIOMapUnique)
+       return( 0 );
+    if( (options ^ _options) & kIOMapReadOnly)
        return( 0 );
-    if( (options ^ _options) & (kIOMapCacheMask | kIOMapReadOnly))
+    if( (kIOMapDefaultCache != (_options & kIOMapCacheMask)) 
+     && ((options ^ _options) & kIOMapCacheMask))
        return( 0 );
 
     if( (0 == (_options & kIOMapAnywhere)) && (logical != toAddress))
@@ -1441,7 +2583,7 @@ _IOMemoryMap * _IOMemoryMap::isCompatible(
     } else {
         mapping = new _IOMemoryMap;
         if( mapping
-        && !mapping->init( owner, this, _offset, _length )) {
+        && !mapping->initCompatible( owner, this, _offset, _length )) {
             mapping->release();
             mapping = 0;
         }
@@ -1451,12 +2593,12 @@ _IOMemoryMap * _IOMemoryMap::isCompatible(
 }
 
 IOPhysicalAddress _IOMemoryMap::getPhysicalSegment( IOByteCount _offset,
-                                                   IOPhysicalLength * length)
+                                                   IOPhysicalLength * _length)
 {
     IOPhysicalAddress  address;
 
     LOCK;
-    address = memory->getPhysicalSegment( offset + _offset, length );
+    address = memory->getPhysicalSegment( offset + _offset, _length );
     UNLOCK;
 
     return( address );
@@ -1473,6 +2615,9 @@ void IOMemoryDescriptor::initialize( void )
 {
     if( 0 == gIOMemoryLock)
        gIOMemoryLock = IORecursiveLockAlloc();
+
+    IORegistryEntry::getRegistryRoot()->setProperty(kIOMaximumMappedIOByteCountKey,
+                                                   ptoa_64(gIOMaximumMappedIOPageCount), 64);
 }
 
 void IOMemoryDescriptor::free( void )
@@ -1486,30 +2631,30 @@ void IOMemoryDescriptor::free( void )
 IOMemoryMap * IOMemoryDescriptor::setMapping(
        task_t                  intoTask,
        IOVirtualAddress        mapAddress,
-       IOOptionBits            options = 0 )
+       IOOptionBits            options )
 {
-    _IOMemoryMap *             map;
+    _IOMemoryMap *             newMap;
 
-    map = new _IOMemoryMap;
+    newMap = new _IOMemoryMap;
 
     LOCK;
 
-    if( map
-     && !map->init( this, intoTask, mapAddress,
+    if( newMap
+     && !newMap->initWithDescriptor( this, intoTask, mapAddress,
                     options | kIOMapStatic, 0, getLength() )) {
-       map->release();
-       map = 0;
+       newMap->release();
+       newMap = 0;
     }
 
-    addMapping( map);
+    addMapping( newMap);
 
     UNLOCK;
 
-    return( map);
+    return( newMap);
 }
 
 IOMemoryMap * IOMemoryDescriptor::map( 
-       IOOptionBits            options = 0 )
+       IOOptionBits            options )
 {
 
     return( makeMapping( this, kernel_task, 0,
@@ -1521,8 +2666,8 @@ IOMemoryMap * IOMemoryDescriptor::map(
        task_t                  intoTask,
        IOVirtualAddress        toAddress,
        IOOptionBits            options,
-       IOByteCount             offset = 0,
-       IOByteCount             length = 0 )
+       IOByteCount             offset,
+       IOByteCount             length )
 {
     if( 0 == length)
        length = getLength();
@@ -1530,6 +2675,69 @@ IOMemoryMap * IOMemoryDescriptor::map(
     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();
+       }
+
+       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 (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);
+       }
+    }
+    while (false);
+
+    UNLOCK;
+
+    if (physMem)
+       physMem->release();
+
+    return (err);
+}
+
 IOMemoryMap * IOMemoryDescriptor::makeMapping(
        IOMemoryDescriptor *    owner,
        task_t                  intoTask,
@@ -1538,50 +2746,127 @@ IOMemoryMap * IOMemoryDescriptor::makeMapping(
        IOByteCount             offset,
        IOByteCount             length )
 {
+    IOMemoryDescriptor * mapDesc = 0;
     _IOMemoryMap *     mapping = 0;
     OSIterator *       iter;
 
     LOCK;
 
-    do {
-       // look for an existing mapping
-       if( (iter = OSCollectionIterator::withCollection( _mappings))) {
+    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();
+           }
 
-            while( (mapping = (_IOMemoryMap *) iter->getNextObject())) {
+           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;
+           }
+       }
+       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->isCompatible( 
-                                       owner, intoTask, toAddress,
-                                       options | kIOMapReference,
-                                       offset, length )))
-                   break;
-            }
-            iter->release();
-            if( mapping)
-                continue;
-        }
 
+       if (mapping)
+           mapping->retain();
 
-       if( mapping || (options & kIOMapReference))
-           continue;
+           if( mapping || (options & kIOMapReference))
+               continue;
 
+           mapDesc = owner;
+           mapDesc->retain();
+       }
        owner = this;
 
         mapping = new _IOMemoryMap;
        if( mapping
-       && !mapping->init( owner, intoTask, toAddress, options,
+       && !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)
+           mapping->retain();
+
     } while( false );
 
-    owner->addMapping( mapping);
+    if (mapping)
+    {
+       mapping->owner = owner;
+       owner->addMapping( mapping);
+       mapping->release();
+    }
 
     UNLOCK;
 
+    if (mapDesc)
+       mapDesc->release();
+
     return( mapping);
 }
 
@@ -1591,19 +2876,16 @@ void IOMemoryDescriptor::addMapping(
     if( mapping) {
         if( 0 == _mappings)
             _mappings = OSSet::withCapacity(1);
-       if( _mappings && _mappings->setObject( mapping ))
-           mapping->release();         /* really */
+       if( _mappings )
+           _mappings->setObject( mapping );
     }
 }
 
 void IOMemoryDescriptor::removeMapping(
        IOMemoryMap * mapping )
 {
-    if( _mappings) {
-        mapping->retain();
-        mapping->retain();
+    if( _mappings)
         _mappings->removeObject( mapping);
-    }
 }
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
@@ -1617,22 +2899,38 @@ OSDefineMetaClassAndStructors(IOSubMemoryDescriptor, IOMemoryDescriptor)
 
 bool IOSubMemoryDescriptor::initSubRange( IOMemoryDescriptor * parent,
                                        IOByteCount offset, IOByteCount length,
-                                       IODirection withDirection )
+                                       IODirection direction )
 {
-    if( !super::init())
-       return( false );
-
     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  = withDirection;
+    _direction  = direction;
     _tag       = parent->getTag();
 
     return( true );
@@ -1669,6 +2967,41 @@ IOPhysicalAddress IOSubMemoryDescriptor::getPhysicalSegment( IOByteCount offset,
     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)
 {
@@ -1676,7 +3009,7 @@ void * IOSubMemoryDescriptor::getVirtualSegment(IOByteCount offset,
 }
 
 IOByteCount IOSubMemoryDescriptor::readBytes(IOByteCount offset,
-                                       void * bytes, IOByteCount withLength)
+                                       void * bytes, IOByteCount length)
 {
     IOByteCount        byteCount;
 
@@ -1687,14 +3020,14 @@ IOByteCount IOSubMemoryDescriptor::readBytes(IOByteCount offset,
 
     LOCK;
     byteCount = _parent->readBytes( _start + offset, bytes,
-                               min(withLength, _length - offset) );
+                               min(length, _length - offset) );
     UNLOCK;
 
     return( byteCount );
 }
 
 IOByteCount IOSubMemoryDescriptor::writeBytes(IOByteCount offset,
-                               const void* bytes, IOByteCount withLength)
+                               const void* bytes, IOByteCount length)
 {
     IOByteCount        byteCount;
 
@@ -1705,14 +3038,44 @@ IOByteCount IOSubMemoryDescriptor::writeBytes(IOByteCount offset,
 
     LOCK;
     byteCount = _parent->writeBytes( _start + offset, bytes,
-                               min(withLength, _length - offset) );
+                               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 = kIODirectionNone)
+               IODirection forDirection)
 {
     IOReturn   err;
 
@@ -1724,7 +3087,7 @@ IOReturn IOSubMemoryDescriptor::prepare(
 }
 
 IOReturn IOSubMemoryDescriptor::complete(
-               IODirection forDirection = kIODirectionNone)
+               IODirection forDirection)
 {
     IOReturn   err;
 
@@ -1743,14 +3106,21 @@ IOMemoryMap * IOSubMemoryDescriptor::makeMapping(
        IOByteCount             offset,
        IOByteCount             length )
 {
-    IOMemoryMap * mapping;
+    IOMemoryMap * mapping = 0;
 
-     mapping = (IOMemoryMap *) _parent->makeMapping(
+    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 );
@@ -1762,17 +3132,17 @@ IOMemoryMap * IOSubMemoryDescriptor::makeMapping(
 
 bool
 IOSubMemoryDescriptor::initWithAddress(void *      address,
-                                    IOByteCount   withLength,
-                                    IODirection withDirection)
+                                    IOByteCount   length,
+                                    IODirection direction)
 {
     return( false );
 }
 
 bool
 IOSubMemoryDescriptor::initWithAddress(vm_address_t address,
-                                    IOByteCount    withLength,
-                                    IODirection  withDirection,
-                                    task_t       withTask)
+                                    IOByteCount    length,
+                                    IODirection  direction,
+                                    task_t       task)
 {
     return( false );
 }
@@ -1780,8 +3150,8 @@ IOSubMemoryDescriptor::initWithAddress(vm_address_t address,
 bool
 IOSubMemoryDescriptor::initWithPhysicalAddress(
                                 IOPhysicalAddress      address,
-                                IOByteCount            withLength,
-                                IODirection            withDirection )
+                                IOByteCount            length,
+                                IODirection            direction )
 {
     return( false );
 }
@@ -1790,9 +3160,9 @@ bool
 IOSubMemoryDescriptor::initWithRanges(
                                        IOVirtualRange * ranges,
                                        UInt32           withCount,
-                                       IODirection      withDirection,
-                                       task_t           withTask,
-                                       bool             asReference = false)
+                                       IODirection      direction,
+                                       task_t           task,
+                                       bool             asReference)
 {
     return( false );
 }
@@ -1800,19 +3170,164 @@ IOSubMemoryDescriptor::initWithRanges(
 bool
 IOSubMemoryDescriptor::initWithPhysicalRanges( IOPhysicalRange * ranges,
                                                UInt32           withCount,
-                                               IODirection      withDirection,
-                                               bool             asReference = false)
+                                               IODirection      direction,
+                                               bool             asReference)
 {
     return( false );
 }
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 0);
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 1);
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 2);
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 3);
-OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 4);
+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;
+       }
+       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) {
+         goto bail;
+       }
+    }
+    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;
+    values[1] = OSNumber::withNumber(_length, sizeof(_length) * 8);
+    if (values[1] == 0) {
+       values[0]->release();
+       return false;
+    }
+    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");
+}
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 0);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 1);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 2);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 3);
+OSMetaClassDefineReservedUsed(IOMemoryDescriptor, 4);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 5);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 6);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 7);
@@ -1824,3 +3339,7 @@ OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 12);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 13);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 14);
 OSMetaClassDefineReservedUnused(IOMemoryDescriptor, 15);
+
+/* ex-inline function implementation */
+IOPhysicalAddress IOMemoryDescriptor::getPhysicalAddress()
+        { return( getPhysicalSegment( 0, 0 )); }