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1/*
2 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
3 *
2d21ac55 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b 5 *
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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.
8f6c56a5 14 *
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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
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20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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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.
8f6c56a5 25 *
2d21ac55 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
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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
38class IOMultiMemoryDescriptor : public IOMemoryDescriptor
39{
40 OSDeclareDefaultStructors(IOMultiMemoryDescriptor);
41
42protected:
43
44 IOMemoryDescriptor ** _descriptors;
45 UInt32 _descriptorsCount;
46 bool _descriptorsIsAllocated;
47
3e170ce0 48 virtual void free() APPLE_KEXT_OVERRIDE;
1c79356b 49
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50public:
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
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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. */
1c79356b 88
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89 virtual addr64_t getPhysicalSegment( IOByteCount offset,
90 IOByteCount * length,
3e170ce0 91 IOOptionBits options = 0 ) APPLE_KEXT_OVERRIDE;
0c530ab8 92
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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
3e170ce0 99 virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
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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
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107 virtual IOReturn complete(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
108
109 virtual IOReturn setPurgeable(IOOptionBits newState, IOOptionBits * oldState) APPLE_KEXT_OVERRIDE;
110
111/*! @function getPageCounts
112 @abstract Retrieve the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
113 @discussion This method returns the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
114 @param residentPageCount - If non-null, a pointer to a byte count that will return the number of resident pages encompassed by this IOMemoryDescriptor.
115 @param dirtyPageCount - If non-null, a pointer to a byte count that will return the number of dirty pages encompassed by this IOMemoryDescriptor.
116 @result An IOReturn code. */
117
118 IOReturn getPageCounts(IOByteCount * residentPageCount,
119 IOByteCount * dirtyPageCount);
120
121#define IOMULTIMEMORYDESCRIPTOR_SUPPORTS_GETPAGECOUNTS 1
122
123private:
124 virtual IOReturn doMap(vm_map_t addressMap,
125 IOVirtualAddress * atAddress,
126 IOOptionBits options,
127 IOByteCount sourceOffset = 0,
128 IOByteCount length = 0 ) APPLE_KEXT_OVERRIDE;
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129};
130
131#endif /* !_IOMULTIMEMORYDESCRIPTOR_H */