1/*
2 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
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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
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9 * compliance with the License. The rights granted to you under the License
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15 * Please obtain a copy of the License at
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27 */
28
29#ifndef _IOMULTIMEMORYDESCRIPTOR_H
30#define _IOMULTIMEMORYDESCRIPTOR_H
31
32#include <IOKit/IOMemoryDescriptor.h>
33#include <libkern/c++/OSPtr.h>
34
35/*! @class IOMultiMemoryDescriptor : public IOMemoryDescriptor
36 * @abstract The IOMultiMemoryDescriptor object describes a memory area made up of several other IOMemoryDescriptors.
37 * @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. */
38
39class IOMultiMemoryDescriptor : public IOMemoryDescriptor
40{
41 OSDeclareDefaultStructors(IOMultiMemoryDescriptor);
42
43protected:
44
45 IOMemoryDescriptor ** _descriptors;
46 UInt32 _descriptorsCount;
47 bool _descriptorsIsAllocated;
48
49 virtual void free() APPLE_KEXT_OVERRIDE;
50
51public:
52
53/*! @function withDescriptors
54 * @abstract Create an IOMultiMemoryDescriptor to describe a memory area made up of several other IOMemoryDescriptors.
55 * @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.
56 * @param descriptors An array of IOMemoryDescriptors which make up the memory to be described.
57 * @param withCount The object count for the descriptors array.
58 * @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.
59 * @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.
60 * @result The created IOMultiMemoryDescriptor on success, to be released by the caller, or zero on failure. */
61
62 static OSPtr<IOMultiMemoryDescriptor> withDescriptors(
63 IOMemoryDescriptor ** descriptors,
64 UInt32 withCount,
65 IODirection withDirection,
66 bool asReference = false );
67
68/*! @function withDescriptors
69 * @abstract Initialize an IOMultiMemoryDescriptor to describe a memory area made up of several other IOMemoryDescriptors.
70 * @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.
71 * @param descriptors An array of IOMemoryDescriptors which make up the memory to be described.
72 * @param withCount The object count for the descriptors array.
73 * @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.
74 * @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.
75 * @result The created IOMultiMemoryDescriptor on success, to be released by the caller, or zero on failure. */
76
77 virtual bool initWithDescriptors(
78 IOMemoryDescriptor ** descriptors,
79 UInt32 withCount,
80 IODirection withDirection,
81 bool asReference = false );
82
83/*! @function getPhysicalSegment
84 * @abstract Break a memory descriptor into its physically contiguous segments.
85 * @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.
86 * @param offset A byte offset into the memory whose physical address to return.
87 * @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
88 * @result A physical address, or zero if the offset is beyond the length of the memory. */
89
90 virtual addr64_t getPhysicalSegment( IOByteCount offset,
91 IOByteCount * length,
92 IOOptionBits options = 0 ) APPLE_KEXT_OVERRIDE;
93
94/*! @function prepare
95 * @abstract Prepare the memory for an I/O transfer.
96 * @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.
97 * @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
98 * @result An IOReturn code. */
99
100 virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
101
102/*! @function complete
103 * @abstract Complete processing of the memory after an I/O transfer finishes.
104 * @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.
105 * @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
106 * @result An IOReturn code. */
107
108 virtual IOReturn complete(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
109
110 virtual IOReturn setPurgeable(IOOptionBits newState, IOOptionBits * oldState) APPLE_KEXT_OVERRIDE;
111
112 IOReturn setOwnership(task_t newOwner, int newLedgerTag, IOOptionBits newOptions);
113
114/*! @function getPageCounts
115 * @abstract Retrieve the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
116 * @discussion This method returns the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
117 * @param residentPageCount - If non-null, a pointer to a byte count that will return the number of resident pages encompassed by this IOMemoryDescriptor.
118 * @param dirtyPageCount - If non-null, a pointer to a byte count that will return the number of dirty pages encompassed by this IOMemoryDescriptor.
119 * @result An IOReturn code. */
120
121 IOReturn getPageCounts(IOByteCount * residentPageCount,
122 IOByteCount * dirtyPageCount);
123
124 virtual uint64_t getPreparationID( void ) APPLE_KEXT_OVERRIDE;
125
126#define IOMULTIMEMORYDESCRIPTOR_SUPPORTS_GETPAGECOUNTS 1
127
128private:
129 virtual IOReturn doMap(vm_map_t addressMap,
130 IOVirtualAddress * atAddress,
131 IOOptionBits options,
132 IOByteCount sourceOffset = 0,
133 IOByteCount length = 0 ) APPLE_KEXT_OVERRIDE;
134};
135
136#endif /* !_IOMULTIMEMORYDESCRIPTOR_H */
137