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
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25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29#ifndef _IOSUBMEMORYDESCRIPTOR_H
30#define _IOSUBMEMORYDESCRIPTOR_H
31
32#include <IOKit/IOMemoryDescriptor.h>
33#include <libkern/c++/OSPtr.h>
34
35/*! @class IOSubMemoryDescriptor : public IOMemoryDescriptor
36 * @abstract The IOSubMemoryDescriptor object describes a memory area made up of a portion of another IOMemoryDescriptor.
37 * @discussion The IOSubMemoryDescriptor object represents a subrange of memory, specified as a portion of another IOMemoryDescriptor. */
38
39class IOSubMemoryDescriptor : public IOMemoryDescriptor
40{
41 OSDeclareDefaultStructors(IOSubMemoryDescriptor);
42
43protected:
44 IOMemoryDescriptor * _parent;
45 IOByteCount _start;
46
47 virtual void free() APPLE_KEXT_OVERRIDE;
48
49public:
50/*! @function withSubRange
51 * @abstract Create an IOMemoryDescriptor to describe a subrange of an existing descriptor.
52 * @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a subrange of the specified memory descriptor. The parent memory descriptor is retained by the new descriptor.
53 * @param of The parent IOMemoryDescriptor of which a subrange is to be used for the new descriptor, which will be retained by the subrange IOMemoryDescriptor.
54 * @param offset A byte offset into the parent memory descriptor's memory.
55 * @param length The length of the subrange.
56 * @param options
57 * kIOMemoryDirectionMask (options:direction) This nibble indicates the I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
58 * @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
59
60 static OSPtr<IOSubMemoryDescriptor> withSubRange(IOMemoryDescriptor *of,
61 IOByteCount offset,
62 IOByteCount length,
63 IOOptionBits options);
64
65/*
66 * Initialize or reinitialize an IOSubMemoryDescriptor to describe
67 * a subrange of an existing descriptor.
68 *
69 * An IOSubMemoryDescriptor can be re-used by calling initSubRange
70 * again on an existing instance -- note that this behavior is not
71 * commonly supported in other IOKit classes, although it is here.
72 */
73 virtual bool initSubRange( IOMemoryDescriptor * parent,
74 IOByteCount offset, IOByteCount length,
75 IODirection withDirection );
76
77/*
78 * IOMemoryDescriptor required methods
79 */
80
81 virtual addr64_t getPhysicalSegment( IOByteCount offset,
82 IOByteCount * length,
83 IOOptionBits options = 0 ) APPLE_KEXT_OVERRIDE;
84
85 virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
86
87 virtual IOReturn complete(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
88
89#ifdef __LP64__
90 virtual IOReturn redirect( task_t safeTask, bool redirect ) APPLE_KEXT_OVERRIDE;
91#else
92 IOReturn redirect( task_t safeTask, bool redirect );
93#endif /* __LP64__ */
94
95 virtual IOReturn setPurgeable( IOOptionBits newState,
96 IOOptionBits * oldState ) APPLE_KEXT_OVERRIDE;
97
98 IOReturn setOwnership( task_t newOwner,
99 int newLedgerTag,
100 IOOptionBits newLedgerOptions );
101
102// support map() on kIOMemoryTypeVirtual without prepare()
103 virtual IOMemoryMap * makeMapping(
104 IOMemoryDescriptor * owner,
105 task_t intoTask,
106 IOVirtualAddress atAddress,
107 IOOptionBits options,
108 IOByteCount offset,
109 IOByteCount length ) APPLE_KEXT_OVERRIDE;
110
111 virtual uint64_t getPreparationID( void ) APPLE_KEXT_OVERRIDE;
112
113/*! @function getPageCounts
114 * @abstract Retrieve the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
115 * @discussion This method returns the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
116 * @param residentPageCount - If non-null, a pointer to a byte count that will return the number of resident pages encompassed by this IOMemoryDescriptor.
117 * @param dirtyPageCount - If non-null, a pointer to a byte count that will return the number of dirty pages encompassed by this IOMemoryDescriptor.
118 * @result An IOReturn code. */
119
120 IOReturn getPageCounts(IOByteCount * residentPageCount,
121 IOByteCount * dirtyPageCount);
122};
123
124#endif /* !_IOSUBMEMORYDESCRIPTOR_H */
125