1 /* 2 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 29 #ifndef _IOSUBMEMORYDESCRIPTOR_H 30 #define _IOSUBMEMORYDESCRIPTOR_H 31 32 #include <IOKit/IOMemoryDescriptor.h> 33 #include <libkern/c++/OSPtr.h> 34 35 /*! @class IOSubMemoryDescriptor : public IOMemoryDescriptor 36 * @abstract The IOSubMemoryDescriptor object describes a memory area made up of a portion of another IOMemoryDescriptor. 37 * @discussion The IOSubMemoryDescriptor object represents a subrange of memory, specified as a portion of another IOMemoryDescriptor. */ 38 39 class IOSubMemoryDescriptor : public IOMemoryDescriptor 40 { 41 OSDeclareDefaultStructors(IOSubMemoryDescriptor); 42 43 protected: 44 IOMemoryDescriptor * _parent; 45 IOByteCount _start; 46 47 virtual void free() APPLE_KEXT_OVERRIDE; 48 49 public: 50 /*! @function withSubRange 51 * @abstract Create an IOMemoryDescriptor to describe a subrange of an existing descriptor. 52 * @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. 53 * @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. 54 * @param offset A byte offset into the parent memory descriptor's memory. 55 * @param length The length of the subrange. 56 * @param options 57 * 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. 58 * @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */ 59 60 static OSPtr<IOSubMemoryDescriptor> withSubRange(IOMemoryDescriptor *of, 61 IOByteCount offset, 62 IOByteCount length, 63 IOOptionBits options); 64 65 /* 66 * Initialize or reinitialize an IOSubMemoryDescriptor to describe 67 * a subrange of an existing descriptor. 68 * 69 * An IOSubMemoryDescriptor can be re-used by calling initSubRange 70 * again on an existing instance -- note that this behavior is not 71 * commonly supported in other IOKit classes, although it is here. 72 */ 73 virtual bool initSubRange( IOMemoryDescriptor * parent, 74 IOByteCount offset, IOByteCount length, 75 IODirection withDirection ); 76 77 /* 78 * IOMemoryDescriptor required methods 79 */ 80 81 virtual addr64_t getPhysicalSegment( IOByteCount offset, 82 IOByteCount * length, 83 IOOptionBits options = 0 ) APPLE_KEXT_OVERRIDE; 84 85 virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE; 86 87 virtual IOReturn complete(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE; 88 89 #ifdef __LP64__ 90 virtual IOReturn redirect( task_t safeTask, bool redirect ) APPLE_KEXT_OVERRIDE; 91 #else 92 IOReturn redirect( task_t safeTask, bool redirect ); 93 #endif /* __LP64__ */ 94 95 virtual IOReturn setPurgeable( IOOptionBits newState, 96 IOOptionBits * oldState ) APPLE_KEXT_OVERRIDE; 97 98 IOReturn setOwnership( task_t newOwner, 99 int newLedgerTag, 100 IOOptionBits newLedgerOptions ); 101 102 // support map() on kIOMemoryTypeVirtual without prepare() 103 virtual IOMemoryMap * makeMapping( 104 IOMemoryDescriptor * owner, 105 task_t intoTask, 106 IOVirtualAddress atAddress, 107 IOOptionBits options, 108 IOByteCount offset, 109 IOByteCount length ) APPLE_KEXT_OVERRIDE; 110 111 virtual uint64_t getPreparationID( void ) APPLE_KEXT_OVERRIDE; 112 113 /*! @function getPageCounts 114 * @abstract Retrieve the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor. 115 * @discussion This method returns the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor. 116 * @param residentPageCount - If non-null, a pointer to a byte count that will return the number of resident pages encompassed by this IOMemoryDescriptor. 117 * @param dirtyPageCount - If non-null, a pointer to a byte count that will return the number of dirty pages encompassed by this IOMemoryDescriptor. 118 * @result An IOReturn code. */ 119 120 IOReturn getPageCounts(IOByteCount * residentPageCount, 121 IOByteCount * dirtyPageCount); 122 }; 123 124 #endif /* !_IOSUBMEMORYDESCRIPTOR_H */ 125