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 _IOMULTIMEMORYDESCRIPTOR_H 30 #define _IOMULTIMEMORYDESCRIPTOR_H 31 32 #include <IOKit/IOMemoryDescriptor.h> 33 #include <libkern/c++/OSPtr.h> 34 35 #if KERNEL_PRIVATE 36 #define IOMULTIMEMORYDESCRIPTOR_EXPORTED 1 37 #endif /* KERNEL_PRIVATE */ 38 39 40 /*! @class IOMultiMemoryDescriptor : public IOMemoryDescriptor 41 * @abstract The IOMultiMemoryDescriptor object describes a memory area made up of several other IOMemoryDescriptors. 42 * @discussion The IOMultiMemoryDescriptor object represents multiple ranges of memory, specified as an ordered list of IOMemoryDescriptors. The descriptors are chained end-to-end to make up a single contiguous buffer. */ 43 44 class IOMultiMemoryDescriptor : public IOMemoryDescriptor 45 { 46 OSDeclareDefaultStructors(IOMultiMemoryDescriptor); 47 48 protected: 49 50 IOMemoryDescriptor ** _descriptors; 51 UInt32 _descriptorsCount; 52 bool _descriptorsIsAllocated; 53 54 virtual void free() APPLE_KEXT_OVERRIDE; 55 56 public: 57 58 /*! @function withDescriptors 59 * @abstract Create an IOMultiMemoryDescriptor to describe a memory area made up of several other IOMemoryDescriptors. 60 * @discussion This method creates and initializes an IOMultiMemoryDescriptor for memory consisting of a number of other IOMemoryDescriptors, chained end-to-end (in the order they appear in the array) to represent a single contiguous memory buffer. Passing the descriptor array as a reference will avoid an extra allocation. 61 * @param descriptors An array of IOMemoryDescriptors which make up the memory to be described. 62 * @param withCount The object count for the descriptors array. 63 * @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures. 64 * @param asReference If false, the IOMultiMemoryDescriptor object will make a copy of the descriptors array, otherwise, the array will be used in situ, avoiding an extra allocation. 65 * @result The created IOMultiMemoryDescriptor on success, to be released by the caller, or zero on failure. */ 66 67 static OSPtr<IOMultiMemoryDescriptor> withDescriptors( 68 IOMemoryDescriptor ** descriptors, 69 UInt32 withCount, 70 IODirection withDirection, 71 bool asReference = false ); 72 73 /*! @function withDescriptors 74 * @abstract Initialize an IOMultiMemoryDescriptor to describe a memory area made up of several other IOMemoryDescriptors. 75 * @discussion This method initializes an IOMultiMemoryDescriptor for memory consisting of a number of other IOMemoryDescriptors, chained end-to-end (in the order they appear in the array) to represent a single contiguous memory buffer. Passing the descriptor array as a reference will avoid an extra allocation. 76 * @param descriptors An array of IOMemoryDescriptors which make up the memory to be described. 77 * @param withCount The object count for the descriptors array. 78 * @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures. 79 * @param asReference If false, the IOMultiMemoryDescriptor object will make a copy of the descriptors array, otherwise, the array will be used in situ, avoiding an extra allocation. 80 * @result The created IOMultiMemoryDescriptor on success, to be released by the caller, or zero on failure. */ 81 82 virtual bool initWithDescriptors( 83 IOMemoryDescriptor ** descriptors, 84 UInt32 withCount, 85 IODirection withDirection, 86 bool asReference = false ); 87 88 /*! @function getPhysicalSegment 89 * @abstract Break a memory descriptor into its physically contiguous segments. 90 * @discussion This method returns the physical address of the byte at the given offset into the memory, and optionally the length of the physically contiguous segment from that offset. 91 * @param offset A byte offset into the memory whose physical address to return. 92 * @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset. 93 * @result A physical address, or zero if the offset is beyond the length of the memory. */ 94 95 virtual addr64_t getPhysicalSegment( IOByteCount offset, 96 IOByteCount * length, 97 IOOptionBits options = 0 ) APPLE_KEXT_OVERRIDE; 98 99 /*! @function prepare 100 * @abstract Prepare the memory for an I/O transfer. 101 * @discussion 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. 102 * @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor. 103 * @result An IOReturn code. */ 104 105 virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE; 106 107 /*! @function complete 108 * @abstract Complete processing of the memory after an I/O transfer finishes. 109 * @discussion This method should not be called unless a prepare was previously issued; the prepare() and complete() must occur in pairs, before and after an I/O transfer involving pageable memory. 110 * @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor. 111 * @result An IOReturn code. */ 112 113 virtual IOReturn complete(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE; 114 115 virtual IOReturn setPurgeable(IOOptionBits newState, IOOptionBits * oldState) APPLE_KEXT_OVERRIDE; 116 117 IOReturn setOwnership(task_t newOwner, int newLedgerTag, IOOptionBits newOptions); 118 119 /*! @function getPageCounts 120 * @abstract Retrieve the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor. 121 * @discussion This method returns the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor. 122 * @param residentPageCount - If non-null, a pointer to a byte count that will return the number of resident pages encompassed by this IOMemoryDescriptor. 123 * @param dirtyPageCount - If non-null, a pointer to a byte count that will return the number of dirty pages encompassed by this IOMemoryDescriptor. 124 * @result An IOReturn code. */ 125 126 IOReturn getPageCounts(IOByteCount * residentPageCount, 127 IOByteCount * dirtyPageCount); 128 129 /*! @function getPageCounts 130 * @abstract Retrieve the number of resident, dirty, and swapped pages encompassed by an IOMemoryDescriptor. 131 * @param residentPageCount - If non-null, a pointer to a byte count that will return the number of resident pages encompassed by this IOMemoryDescriptor. 132 * @param dirtyPageCount - If non-null, a pointer to a byte count that will return the number of resident, dirty pages encompassed by this IOMemoryDescriptor. 133 * @param swappedPageCount - If non-null, a pointer to a byte count that will return the number of swapped pages encompassed by this IOMemoryDescriptor. 134 * @result An IOReturn code. */ 135 136 IOReturn getPageCounts( IOByteCount * residentPageCount, 137 IOByteCount * dirtyPageCount, 138 IOByteCount * swappedPageCount ); 139 140 virtual uint64_t getPreparationID( void ) APPLE_KEXT_OVERRIDE; 141 142 #define IOMULTIMEMORYDESCRIPTOR_SUPPORTS_GETPAGECOUNTS 1 143 144 private: 145 virtual IOReturn doMap(vm_map_t addressMap, 146 IOVirtualAddress * atAddress, 147 IOOptionBits options, 148 IOByteCount sourceOffset = 0, 149 IOByteCount length = 0 ) APPLE_KEXT_OVERRIDE; 150 }; 151 152 #endif /* !_IOMULTIMEMORYDESCRIPTOR_H */ 153