/*
* Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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*/
#ifndef _IOSUBMEMORYDESCRIPTOR_H
#define _IOSUBMEMORYDESCRIPTOR_H
#include <IOKit/IOMemoryDescriptor.h>
#include <libkern/c++/OSPtr.h>
/*! @class IOSubMemoryDescriptor : public IOMemoryDescriptor
* @abstract The IOSubMemoryDescriptor object describes a memory area made up of a portion of another IOMemoryDescriptor.
* @discussion The IOSubMemoryDescriptor object represents a subrange of memory, specified as a portion of another IOMemoryDescriptor. */
class IOSubMemoryDescriptor : public IOMemoryDescriptor
{
OSDeclareDefaultStructors(IOSubMemoryDescriptor);
protected:
IOMemoryDescriptor * _parent;
IOByteCount _start;
virtual void free() APPLE_KEXT_OVERRIDE;
public:
/*! @function withSubRange
* @abstract Create an IOMemoryDescriptor to describe a subrange of an existing descriptor.
* @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a subrange of the specified memory descriptor. The parent memory descriptor is retained by the new descriptor.
* @param of The parent IOMemoryDescriptor of which a subrange is to be used for the new descriptor, which will be retained by the subrange IOMemoryDescriptor.
* @param offset A byte offset into the parent memory descriptor's memory.
* @param length The length of the subrange.
* @param options
* kIOMemoryDirectionMask (options:direction) This nibble indicates the I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
* @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
static OSPtr<IOSubMemoryDescriptor> withSubRange(IOMemoryDescriptor *of,
IOByteCount offset,
IOByteCount length,
IOOptionBits options);
/*
* Initialize or reinitialize an IOSubMemoryDescriptor to describe
* a subrange of an existing descriptor.
*
* An IOSubMemoryDescriptor can be re-used by calling initSubRange
* again on an existing instance -- note that this behavior is not
* commonly supported in other IOKit classes, although it is here.
*/
virtual bool initSubRange( IOMemoryDescriptor * parent,
IOByteCount offset, IOByteCount length,
IODirection withDirection );
/*
* IOMemoryDescriptor required methods
*/
virtual addr64_t getPhysicalSegment( IOByteCount offset,
IOByteCount * length,
IOOptionBits options = 0 ) APPLE_KEXT_OVERRIDE;
virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
virtual IOReturn complete(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
#ifdef __LP64__
virtual IOReturn redirect( task_t safeTask, bool redirect ) APPLE_KEXT_OVERRIDE;
#else
IOReturn redirect( task_t safeTask, bool redirect );
#endif /* __LP64__ */
virtual IOReturn setPurgeable( IOOptionBits newState,
IOOptionBits * oldState ) APPLE_KEXT_OVERRIDE;
IOReturn setOwnership( task_t newOwner,
int newLedgerTag,
IOOptionBits newLedgerOptions );
// support map() on kIOMemoryTypeVirtual without prepare()
virtual IOMemoryMap * makeMapping(
IOMemoryDescriptor * owner,
task_t intoTask,
IOVirtualAddress atAddress,
IOOptionBits options,
IOByteCount offset,
IOByteCount length ) APPLE_KEXT_OVERRIDE;
virtual uint64_t getPreparationID( void ) APPLE_KEXT_OVERRIDE;
/*! @function getPageCounts
* @abstract Retrieve the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
* @discussion This method returns the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
* @param residentPageCount - If non-null, a pointer to a byte count that will return the number of resident pages encompassed by this IOMemoryDescriptor.
* @param dirtyPageCount - If non-null, a pointer to a byte count that will return the number of dirty pages encompassed by this IOMemoryDescriptor.
* @result An IOReturn code. */
IOReturn getPageCounts(IOByteCount * residentPageCount,
IOByteCount * dirtyPageCount);
};
#endif /* !_IOSUBMEMORYDESCRIPTOR_H */