1 | /* |
2 | * Copyright (c) 1998-2020 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, |
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23 | * Please see the License for the specific language governing rights and |
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26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
27 | */ |
28 | |
29 | #ifndef _IOGUARDPAGEMEMORYDESCRIPTOR_H |
30 | #define _IOGUARDPAGEMEMORYDESCRIPTOR_H |
31 | |
32 | #include <IOKit/IOMemoryDescriptor.h> |
33 | #include <libkern/c++/OSPtr.h> |
34 | |
35 | /*! |
36 | * @class IOGuardPageMemoryDescriptor |
37 | * @abstract Provides a memory descriptor that allows for variable size guard regions. Use with |
38 | * IOMultiMemoryDescriptor to surround other memory descriptors with guard pages. |
39 | */ |
40 | class IOGuardPageMemoryDescriptor : public IOGeneralMemoryDescriptor |
41 | { |
42 | OSDeclareDefaultStructors(IOGuardPageMemoryDescriptor); |
43 | |
44 | protected: |
45 | virtual void free() APPLE_KEXT_OVERRIDE; |
46 | |
47 | vm_offset_t _buffer; |
48 | vm_size_t _size; |
49 | |
50 | public: |
51 | |
52 | /* @function withSize |
53 | * @discussion Create a IOGuardPageMemoryDescriptor with the specified size. |
54 | * @param Size of the guard region. This will be rounded up to the nearest multiple of page size. |
55 | * @return IOGuardPageMemoryDescriptor instance to be released by the caller, which will free the allocated |
56 | * virtual memory region. |
57 | */ |
58 | static OSPtr<IOGuardPageMemoryDescriptor> withSize(vm_size_t size); |
59 | |
60 | virtual bool initWithSize(vm_size_t size); |
61 | |
62 | private: |
63 | virtual IOReturn doMap(vm_map_t addressMap, |
64 | IOVirtualAddress * atAddress, |
65 | IOOptionBits options, |
66 | IOByteCount sourceOffset = 0, |
67 | IOByteCount length = 0 ) APPLE_KEXT_OVERRIDE; |
68 | }; |
69 | |
70 | #endif /* !_IOGUARDPAGEMEMORYDESCRIPTOR_H */ |
71 | |