| 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 | ␊ |
| 34 | /*! @class IOMultiMemoryDescriptor : public IOMemoryDescriptor␊ |
| 35 | @abstract The IOMultiMemoryDescriptor object describes a memory area made up of several other IOMemoryDescriptors.␊ |
| 36 | @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. */␊ |
| 37 | ␊ |
| 38 | class IOMultiMemoryDescriptor : public IOMemoryDescriptor␊ |
| 39 | {␊ |
| 40 | OSDeclareDefaultStructors(IOMultiMemoryDescriptor);␊ |
| 41 | ␊ |
| 42 | protected:␊ |
| 43 | ␊ |
| 44 | IOMemoryDescriptor ** _descriptors;␊ |
| 45 | UInt32 _descriptorsCount;␊ |
| 46 | bool _descriptorsIsAllocated;␊ |
| 47 | ␊ |
| 48 | virtual void free();␊ |
| 49 | ␊ |
| 50 | public:␊ |
| 51 | ␊ |
| 52 | /*! @function withDescriptors␊ |
| 53 | @abstract Create an IOMultiMemoryDescriptor to describe a memory area made up of several other IOMemoryDescriptors.␊ |
| 54 | @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.␊ |
| 55 | @param descriptors An array of IOMemoryDescriptors which make up the memory to be described.␊ |
| 56 | @param withCount The object count for the descriptors array.␊ |
| 57 | @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.␊ |
| 58 | @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.␊ |
| 59 | @result The created IOMultiMemoryDescriptor on success, to be released by the caller, or zero on failure. */␊ |
| 60 | ␊ |
| 61 | static IOMultiMemoryDescriptor * withDescriptors(␊ |
| 62 | IOMemoryDescriptor ** descriptors,␊ |
| 63 | UInt32 withCount,␊ |
| 64 | IODirection withDirection,␊ |
| 65 | bool asReference = false );␊ |
| 66 | ␊ |
| 67 | /*! @function withDescriptors␊ |
| 68 | @abstract Initialize an IOMultiMemoryDescriptor to describe a memory area made up of several other IOMemoryDescriptors.␊ |
| 69 | @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.␊ |
| 70 | @param descriptors An array of IOMemoryDescriptors which make up the memory to be described.␊ |
| 71 | @param withCount The object count for the descriptors array.␊ |
| 72 | @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.␊ |
| 73 | @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.␊ |
| 74 | @result The created IOMultiMemoryDescriptor on success, to be released by the caller, or zero on failure. */␊ |
| 75 | ␊ |
| 76 | virtual bool initWithDescriptors(␊ |
| 77 | IOMemoryDescriptor ** descriptors,␊ |
| 78 | UInt32 withCount,␊ |
| 79 | IODirection withDirection,␊ |
| 80 | bool asReference = false );␊ |
| 81 | ␊ |
| 82 | /*! @function getPhysicalSegment␊ |
| 83 | @abstract Break a memory descriptor into its physically contiguous segments.␊ |
| 84 | @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.␊ |
| 85 | @param offset A byte offset into the memory whose physical address to return.␊ |
| 86 | @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.␊ |
| 87 | @result A physical address, or zero if the offset is beyond the length of the memory. */␊ |
| 88 | ␊ |
| 89 | virtual addr64_t getPhysicalSegment( IOByteCount offset,␊ |
| 90 | IOByteCount * length,␊ |
| 91 | IOOptionBits options = 0 );␊ |
| 92 | ␊ |
| 93 | /*! @function prepare␊ |
| 94 | @abstract Prepare the memory for an I/O transfer.␊ |
| 95 | @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.␊ |
| 96 | @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.␊ |
| 97 | @result An IOReturn code. */␊ |
| 98 | ␊ |
| 99 | virtual IOReturn prepare(IODirection forDirection = kIODirectionNone);␊ |
| 100 | ␊ |
| 101 | /*! @function complete␊ |
| 102 | @abstract Complete processing of the memory after an I/O transfer finishes.␊ |
| 103 | @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.␊ |
| 104 | @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.␊ |
| 105 | @result An IOReturn code. */␊ |
| 106 | ␊ |
| 107 | virtual IOReturn complete(IODirection forDirection = kIODirectionNone);␊ |
| 108 | };␊ |
| 109 | ␊ |
| 110 | #endif /* !_IOMULTIMEMORYDESCRIPTOR_H */␊ |
| 111 | |
