| 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 _IOINTERLEAVEDMEMORYDESCRIPTOR_H␊ |
| 30 | #define _IOINTERLEAVEDMEMORYDESCRIPTOR_H␊ |
| 31 | ␊ |
| 32 | #include <IOKit/IOMemoryDescriptor.h>␊ |
| 33 | ␊ |
| 34 | /*! @class IOInterleavedMemoryDescriptor : public IOMemoryDescriptor␊ |
| 35 | @abstract The IOInterleavedMemoryDescriptor object describes a memory area made up of portions of several other IOMemoryDescriptors.␊ |
| 36 | @discussion The IOInterleavedMemoryDescriptor object represents interleaved ranges of memory, specified as an ordered list of portions of individual IOMemoryDescriptors. The portions are chained end-to-end to make up a single contiguous buffer. */␊ |
| 37 | ␊ |
| 38 | class IOInterleavedMemoryDescriptor : public IOMemoryDescriptor␊ |
| 39 | {␊ |
| 40 | OSDeclareDefaultStructors(IOInterleavedMemoryDescriptor);␊ |
| 41 | ␊ |
| 42 | protected:␊ |
| 43 | ␊ |
| 44 | IOByteCount _descriptorCapacity;␊ |
| 45 | UInt32 _descriptorCount;␊ |
| 46 | IOMemoryDescriptor ** _descriptors;␊ |
| 47 | IOByteCount * _descriptorOffsets;␊ |
| 48 | IOByteCount * _descriptorLengths;␊ |
| 49 | bool _descriptorPrepared;␊ |
| 50 | ␊ |
| 51 | virtual void free();␊ |
| 52 | ␊ |
| 53 | public:␊ |
| 54 | ␊ |
| 55 | /*! @function withCapacity␊ |
| 56 | @abstract Create an IOInterleavedMemoryDescriptor to describe a memory area made up of several other IOMemoryDescriptors.␊ |
| 57 | @discussion This method creates and initializes an IOInterleavedMemoryDescriptor for memory consisting of portions 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.␊ |
| 58 | @param capacity The maximum number of IOMemoryDescriptors that may be subsequently added to this IOInterleavedMemoryDescriptor.␊ |
| 59 | @param direction An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.␊ |
| 60 | @result The created IOInterleavedMemoryDescriptor on success, to be released by the caller, or zero on failure. */␊ |
| 61 | ␊ |
| 62 | static IOInterleavedMemoryDescriptor * withCapacity( IOByteCount␉ capacity,␊ |
| 63 | IODirection direction);␊ |
| 64 | ␊ |
| 65 | /*! @function initWithCapacity␊ |
| 66 | @abstract Initialize an IOInterleavedMemoryDescriptor to describe a memory area made up of several other IOMemoryDescriptors.␊ |
| 67 | @discussion This method initializes an IOInterleavedMemoryDescriptor for memory consisting of portions 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.␊ |
| 68 | @param capacity The maximum number of IOMemoryDescriptors that may be subsequently added to this IOInterleavedMemoryDescriptor.␊ |
| 69 | @param direction An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.␊ |
| 70 | @result The created IOInterleavedMemoryDescriptor on success, to be released by the caller, or zero on failure. */␊ |
| 71 | ␊ |
| 72 | virtual bool initWithCapacity( IOByteCount capacity,␊ |
| 73 | IODirection direction );␊ |
| 74 | ␊ |
| 75 | /*! @function clearMemoryDescriptors␊ |
| 76 | @abstract Clear all of the IOMemoryDescriptors currently contained in and reset the IOInterleavedMemoryDescriptor.␊ |
| 77 | @discussion Clears each IOMemoryDescriptor by completing (if needed) and releasing. The IOInterleavedMemoryDescriptor is then reset and may accept new descriptors up to the capacity specified when it was created.␊ |
| 78 | @param direction 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 | ␊ |
| 80 | virtual void clearMemoryDescriptors( IODirection direction = kIODirectionNone );␊ |
| 81 | ␊ |
| 82 | /*! @function setMemoryDescriptor␊ |
| 83 | @abstract Add a portion of an IOMemoryDescriptor to the IOInterleavedMemoryDescriptor.␊ |
| 84 | @discussion This method adds the portion of an IOMemoryDescriptor described by the offset and length parameters to the end of the IOInterleavedMemoryDescriptor. A single IOMemoryDescriptor may be added as many times as there is room for it. The offset and length must describe a portion entirely within the IOMemoryDescriptor.␊ |
| 85 | @param descriptor An IOMemoryDescriptor to be added to the IOInterleavedMemoryDescriptor. Its direction must be compatible with that of the IOInterleavedMemoryDescriptor.␊ |
| 86 | @param offset The offset into the IOMemoryDescriptor of the portion that will be added to the virtualized buffer.␊ |
| 87 | @param length The length of the portion of the IOMemoryDescriptor to be added to the virtualized buffer. ␊ |
| 88 | @result Returns true the portion was successfully added. */␊ |
| 89 | ␊ |
| 90 | virtual bool setMemoryDescriptor( IOMemoryDescriptor * descriptor,␊ |
| 91 | IOByteCount offset,␊ |
| 92 | IOByteCount length );␊ |
| 93 | ␊ |
| 94 | /*! @function getPhysicalSegment␊ |
| 95 | @abstract Break a memory descriptor into its physically contiguous segments.␊ |
| 96 | @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.␊ |
| 97 | @param offset A byte offset into the memory whose physical address to return.␊ |
| 98 | @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.␊ |
| 99 | @result A physical address, or zero if the offset is beyond the length of the memory. */␊ |
| 100 | ␊ |
| 101 | virtual addr64_t getPhysicalSegment( IOByteCount offset,␊ |
| 102 | IOByteCount * length,␊ |
| 103 | IOOptionBits options = 0 );␊ |
| 104 | ␊ |
| 105 | /*! @function prepare␊ |
| 106 | @abstract Prepare the memory for an I/O transfer.␊ |
| 107 | @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 need not called for non-pageable memory.␊ |
| 108 | @param forDirection The direction of the I/O to be performed, or kIODirectionNone for the direction specified by the memory descriptor.␊ |
| 109 | @result An IOReturn code. */␊ |
| 110 | ␊ |
| 111 | virtual IOReturn prepare(IODirection forDirection = kIODirectionNone);␊ |
| 112 | ␊ |
| 113 | /*! @function complete␊ |
| 114 | @abstract Complete processing of the memory after an I/O transfer finishes.␊ |
| 115 | @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.␊ |
| 116 | @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.␊ |
| 117 | @result An IOReturn code. */␊ |
| 118 | ␊ |
| 119 | virtual IOReturn complete(IODirection forDirection = kIODirectionNone);␊ |
| 120 | };␊ |
| 121 | ␊ |
| 122 | #endif /* !_IOINTERLEAVEDMEMORYDESCRIPTOR_H */␊ |
| 123 | |
