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iokit/Kernel/IOBufferMemoryDescriptor.cpp xnu-344.2 xnu-792.1.5
--- xnu/xnu-344.2/iokit/Kernel/IOBufferMemoryDescriptor.cpp
+++ xnu/xnu-792.1.5/iokit/Kernel/IOBufferMemoryDescriptor.cpp
@@ -25,12 +25,14 @@
 #include <IOKit/IOLib.h>
 #include <IOKit/IOBufferMemoryDescriptor.h>
 
+#include "IOKitKernelInternal.h"
+
 __BEGIN_DECLS
 void ipc_port_release_send(ipc_port_t port);
 #include <vm/pmap.h>
+
+vm_map_t IOPageableMapForAddress( vm_address_t address );
 __END_DECLS
-
-extern "C" vm_map_t IOPageableMapForAddress( vm_address_t address );
 
 #define super IOGeneralMemoryDescriptor
 OSDefineMetaClassAndStructors(IOBufferMemoryDescriptor,
@@ -86,7 +88,9 @@
                                vm_offset_t  alignment,
 			       task_t	    inTask)
 {
-    vm_map_t map = 0;
+    kern_return_t 	kr;
+    vm_map_t 		vmmap = 0;
+    IOOptionBits	iomdOptions = kIOMemoryAsReference | kIOMemoryTypeVirtual;
 
     if (!capacity)
         return false;
@@ -97,6 +101,9 @@
     _physSegCount = 0;
     _buffer	  = 0;
 
+    // Grab the direction and the Auto Prepare bits from the Buffer MD options
+    iomdOptions  |= options & (kIOMemoryDirectionMask | kIOMemoryAutoPrepare);
+
     if ((options & kIOMemorySharingTypeMask) && (alignment < page_size))
         alignment = page_size;
 
@@ -106,38 +113,87 @@
     _alignment = alignment;
     if (options & kIOMemoryPageable)
     {
-	if (inTask == kernel_task)
+        iomdOptions |= kIOMemoryBufferPageable;
+
+        ipc_port_t sharedMem;
+        vm_size_t size = round_page_32(capacity);
+
+        // must create the entry before any pages are allocated
+
+	// set flags for entry + object create
+	vm_prot_t memEntryCacheMode = VM_PROT_READ | VM_PROT_WRITE
+				    | MAP_MEM_NAMED_CREATE;
+
+        if (options & kIOMemoryPurgeable)
+            memEntryCacheMode |= MAP_MEM_PURGABLE;
+
+	// set memory entry cache mode
+	switch (options & kIOMapCacheMask)
 	{
-	    /* Allocate some kernel address space. */
-	    _buffer = IOMallocPageable(capacity, alignment);
-	    if (_buffer)
-		map = IOPageableMapForAddress((vm_address_t) _buffer);
+	    case kIOMapInhibitCache:
+		SET_MAP_MEM(MAP_MEM_IO, memEntryCacheMode);
+		break;
+    
+	    case kIOMapWriteThruCache:
+		SET_MAP_MEM(MAP_MEM_WTHRU, memEntryCacheMode);
+		break;
+
+	    case kIOMapWriteCombineCache:
+		SET_MAP_MEM(MAP_MEM_WCOMB, memEntryCacheMode);
+		break;
+
+	    case kIOMapCopybackCache:
+		SET_MAP_MEM(MAP_MEM_COPYBACK, memEntryCacheMode);
+		break;
+
+	    case kIOMapDefaultCache:
+	    default:
+		SET_MAP_MEM(MAP_MEM_NOOP, memEntryCacheMode);
+		break;
+	}
+
+	kr = mach_make_memory_entry( vmmap,
+		    &size, 0,
+		    memEntryCacheMode, &sharedMem,
+		    NULL );
+
+	if( (KERN_SUCCESS == kr) && (size != round_page_32(capacity))) {
+	    ipc_port_release_send( sharedMem );
+	    kr = kIOReturnVMError;
+	}
+	if( KERN_SUCCESS != kr)
+	    return( false );
+
+	_memEntry = (void *) sharedMem;
+#if IOALLOCDEBUG
+       debug_iomallocpageable_size += size;
+#endif
+	if ((NULL == inTask) && (options & kIOMemoryPageable))
+	    inTask = kernel_task;
+	else if (inTask == kernel_task)
+	{
+	    vmmap = kernel_map;
 	}
 	else
 	{
-	    kern_return_t kr;
 
 	    if( !reserved) {
 		reserved = IONew( ExpansionData, 1 );
 		if( !reserved)
 		    return( false );
 	    }
-	    map = get_task_map(inTask);
-	    vm_map_reference(map);
-	    reserved->map = map;
-	    kr = vm_allocate( map, (vm_address_t *) &_buffer, round_page(capacity),
-				VM_FLAGS_ANYWHERE | VM_MAKE_TAG(VM_MEMORY_IOKIT) );
-	    if( KERN_SUCCESS != kr)
-		return( false );
-
-	    // we have to make sure that these pages don't get copied on fork.
-	    kr = vm_inherit( map, (vm_address_t) _buffer, round_page(capacity), VM_INHERIT_NONE);
-	    if( KERN_SUCCESS != kr)
-		return( false );
+	    vmmap = get_task_map(inTask);
+	    vm_map_reference(vmmap);
+	    reserved->map = vmmap;
 	}
     }
     else 
     {
+        // @@@ gvdl: Need to remove this
+        // Buffer should never auto prepare they should be prepared explicitly
+        // But it never was enforced so what are you going to do?
+        iomdOptions |= kIOMemoryAutoPrepare;
+
 	/* Allocate a wired-down buffer inside kernel space. */
 	if (options & kIOMemoryPhysicallyContiguous)
 	    _buffer = IOMallocContiguous(capacity, alignment, 0);
@@ -145,58 +201,32 @@
 	    _buffer = IOMallocAligned(capacity, alignment);
 	else
 	    _buffer = IOMalloc(capacity);
-    }
-
-    if (!_buffer)
-	return false;
+
+	if (!_buffer)
+	    return false;
+    }
 
     _singleRange.v.address = (vm_address_t) _buffer;
     _singleRange.v.length  = capacity;
 
-    if (!super::initWithRanges(&_singleRange.v,	1,
-                                (IODirection) (options & kIOMemoryDirectionMask),
-                                inTask, true))
+    if (!super::initWithOptions(&_singleRange.v, 1, 0,
+                               inTask, iomdOptions, /* System mapper */ 0))
 	return false;
 
     if (options & kIOMemoryPageable)
     {
-        _flags |= kIOMemoryRequiresWire;
-
         kern_return_t kr;
-        ipc_port_t sharedMem = (ipc_port_t) _memEntry;
-        vm_size_t size = round_page(_ranges.v[0].length);
-
-        // must create the entry before any pages are allocated
-        if( 0 == sharedMem) {
-            kr = mach_make_memory_entry( map,
-                        &size, _ranges.v[0].address,
-                        VM_PROT_READ | VM_PROT_WRITE, &sharedMem,
-                        NULL );
-            if( (KERN_SUCCESS == kr) && (size != round_page(_ranges.v[0].length))) {
-                ipc_port_release_send( sharedMem );
-                kr = kIOReturnVMError;
-            }
-            if( KERN_SUCCESS != kr)
-                sharedMem = 0;
-            _memEntry = (void *) sharedMem;
-        }
-    }
-    else
-    {
-        /* Precompute virtual-to-physical page mappings. */
-        vm_address_t inBuffer = (vm_address_t) _buffer;
-        _physSegCount = atop(trunc_page(inBuffer + capacity - 1) -
-                            trunc_page(inBuffer)) + 1;
-        _physAddrs = IONew(IOPhysicalAddress, _physSegCount);
-        if (!_physAddrs)
-            return false;
-    
-        inBuffer = trunc_page(inBuffer);
-        for (unsigned i = 0; i < _physSegCount; i++) {
-            _physAddrs[i] = pmap_extract(get_task_pmap(kernel_task), inBuffer);
-            assert(_physAddrs[i]); /* supposed to be wired */
-            inBuffer += page_size;
-        }
+
+	if (vmmap)
+	{
+	    kr = doMap(vmmap, (IOVirtualAddress *) &_buffer, kIOMapAnywhere, 0, round_page_32(capacity));
+	    if (KERN_SUCCESS != kr)
+	    {
+		_buffer = 0;
+		return( false );
+	    }
+	    _singleRange.v.address = (vm_address_t) _buffer;
+	}
     }
 
     setLength(capacity);
@@ -208,7 +238,7 @@
 					    task_t       inTask,
                                             IOOptionBits options,
                                             vm_size_t    capacity,
-                                            vm_offset_t  alignment = 1)
+                                            vm_offset_t  alignment)
 {
     IOBufferMemoryDescriptor *me = new IOBufferMemoryDescriptor;
     
@@ -230,7 +260,7 @@
 IOBufferMemoryDescriptor * IOBufferMemoryDescriptor::withOptions(
                                             IOOptionBits options,
                                             vm_size_t    capacity,
-                                            vm_offset_t  alignment = 1)
+                                            vm_offset_t  alignment)
 {
     IOBufferMemoryDescriptor *me = new IOBufferMemoryDescriptor;
     
@@ -313,45 +343,48 @@
  */
 void IOBufferMemoryDescriptor::free()
 {
+    // Cache all of the relevant information on the stack for use
+    // after we call super::free()!
     IOOptionBits options   = _options;
     vm_size_t    size	   = _capacity;
     void *       buffer	   = _buffer;
-    vm_map_t	 map	   = 0;
+    vm_map_t	 vmmap	   = 0;
     vm_offset_t  alignment = _alignment;
 
-    if (_physAddrs)
-        IODelete(_physAddrs, IOPhysicalAddress, _physSegCount);
-
     if (reserved)
     {
-	map = reserved->map;
+	vmmap = reserved->map;
         IODelete( reserved, ExpansionData, 1 );
     }
 
     /* super::free may unwire - deallocate buffer afterwards */
     super::free();
 
-    if (buffer)
-    {
-        if (options & kIOMemoryPageable)
-	{
-	    if (map)
-		vm_deallocate(map, (vm_address_t) buffer, round_page(size));
-	    else
-	       IOFreePageable(buffer, size);
-	}
+    if (options & kIOMemoryPageable)
+    {
+#if IOALLOCDEBUG
+        if (!buffer || vmmap)
+            debug_iomallocpageable_size -= round_page_32(size);
+#endif
+        if (buffer)
+        {
+            if (vmmap)
+                vm_deallocate(vmmap, (vm_address_t) buffer, round_page_32(size));
+            else
+                IOFreePageable(buffer, size);
+        }
+    }
+    else if (buffer)
+    {
+        if (options & kIOMemoryPhysicallyContiguous)
+            IOFreeContiguous(buffer, size);
+        else if (alignment > 1)
+            IOFreeAligned(buffer, size);
         else
-	{
-            if (options & kIOMemoryPhysicallyContiguous)
-                IOFreeContiguous(buffer, size);
-            else if (alignment > 1)
-                IOFreeAligned(buffer, size);
-            else
-                IOFree(buffer, size);
-        }
-    }
-    if (map)
-	vm_map_deallocate(map);
+            IOFree(buffer, size);
+    }
+    if (vmmap)
+	vm_map_deallocate(vmmap);
 }
 
 /*
@@ -436,55 +469,6 @@
     if (start < _length && (start + withLength) <= _length)
         return (void *)(_singleRange.v.address + start);
     return 0;
-}
-
-/*
- * 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
-IOBufferMemoryDescriptor::getPhysicalSegment(IOByteCount offset,
-					IOByteCount * lengthOfSegment)
-{
-    IOPhysicalAddress physAddr;
-
-    if( offset != _position)
-	setPosition( offset );
-
-    assert(_position <= _length);
-
-    /* Fail gracefully if the position is at (or past) the end-of-buffer. */
-    if (_position >= _length) {
-        *lengthOfSegment = 0;
-        return 0;
-    }
-
-    if (_options & kIOMemoryPageable) {
-        physAddr = super::getPhysicalSegment(offset, lengthOfSegment);
-
-    } else {
-        /* Compute the largest contiguous physical length possible. */
-        vm_address_t actualPos  = _singleRange.v.address + _position;
-        vm_address_t actualPage = trunc_page(actualPos);
-        unsigned     physInd    = atop(actualPage-trunc_page(_singleRange.v.address));
-    
-        vm_size_t physicalLength = actualPage + page_size - actualPos;
-        for (unsigned index = physInd + 1; index < _physSegCount &&
-            _physAddrs[index] == _physAddrs[index-1] + page_size; index++) {
-            physicalLength += page_size;
-        }
-    
-        /* Clip contiguous physical length at the end-of-buffer. */
-        if (physicalLength > _length - _position)
-            physicalLength = _length - _position;
-    
-        *lengthOfSegment = physicalLength;
-        physAddr = _physAddrs[physInd] + (actualPos - actualPage);
-    }
-
-    return physAddr;
 }
 
 OSMetaClassDefineReservedUsed(IOBufferMemoryDescriptor, 0);