xref: /xnu-8796.101.5/iokit/IOKit/IOGuardPageMemoryDescriptor.h (revision aca3beaa3dfbd42498b42c5e5ce20a938e6554e5)
1*aca3beaaSApple OSS Distributions /*
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28*aca3beaaSApple OSS Distributions 
29*aca3beaaSApple OSS Distributions #ifndef _IOGUARDPAGEMEMORYDESCRIPTOR_H
30*aca3beaaSApple OSS Distributions #define _IOGUARDPAGEMEMORYDESCRIPTOR_H
31*aca3beaaSApple OSS Distributions 
32*aca3beaaSApple OSS Distributions #include <IOKit/IOMemoryDescriptor.h>
33*aca3beaaSApple OSS Distributions #include <libkern/c++/OSPtr.h>
34*aca3beaaSApple OSS Distributions 
35*aca3beaaSApple OSS Distributions /*!
36*aca3beaaSApple OSS Distributions  *   @class IOGuardPageMemoryDescriptor
37*aca3beaaSApple OSS Distributions  *   @abstract Provides a memory descriptor that allows for variable size guard regions. Use with
38*aca3beaaSApple OSS Distributions  *             IOMultiMemoryDescriptor to surround other memory descriptors with guard pages.
39*aca3beaaSApple OSS Distributions  */
40*aca3beaaSApple OSS Distributions class IOGuardPageMemoryDescriptor : public IOGeneralMemoryDescriptor
41*aca3beaaSApple OSS Distributions {
42*aca3beaaSApple OSS Distributions 	OSDeclareDefaultStructors(IOGuardPageMemoryDescriptor);
43*aca3beaaSApple OSS Distributions 
44*aca3beaaSApple OSS Distributions protected:
45*aca3beaaSApple OSS Distributions 	virtual void free() APPLE_KEXT_OVERRIDE;
46*aca3beaaSApple OSS Distributions 
47*aca3beaaSApple OSS Distributions 	vm_offset_t    _buffer;
48*aca3beaaSApple OSS Distributions 	vm_size_t      _size;
49*aca3beaaSApple OSS Distributions 
50*aca3beaaSApple OSS Distributions public:
51*aca3beaaSApple OSS Distributions 
52*aca3beaaSApple OSS Distributions 	/* @function withSize
53*aca3beaaSApple OSS Distributions 	 *  @discussion Create a IOGuardPageMemoryDescriptor with the specified size.
54*aca3beaaSApple OSS Distributions 	 *  @param Size of the guard region. This will be rounded up to the nearest multiple of page size.
55*aca3beaaSApple OSS Distributions 	 *  @return IOGuardPageMemoryDescriptor instance to be released by the caller, which will free the allocated
56*aca3beaaSApple OSS Distributions 	 *          virtual memory region.
57*aca3beaaSApple OSS Distributions 	 */
58*aca3beaaSApple OSS Distributions 	static OSPtr<IOGuardPageMemoryDescriptor> withSize(vm_size_t size);
59*aca3beaaSApple OSS Distributions 
60*aca3beaaSApple OSS Distributions 	virtual bool initWithSize(vm_size_t size);
61*aca3beaaSApple OSS Distributions 
62*aca3beaaSApple OSS Distributions private:
63*aca3beaaSApple OSS Distributions 	virtual IOReturn doMap(vm_map_t           addressMap,
64*aca3beaaSApple OSS Distributions 	    IOVirtualAddress * atAddress,
65*aca3beaaSApple OSS Distributions 	    IOOptionBits       options,
66*aca3beaaSApple OSS Distributions 	    IOByteCount        sourceOffset = 0,
67*aca3beaaSApple OSS Distributions 	    IOByteCount        length = 0 ) APPLE_KEXT_OVERRIDE;
68*aca3beaaSApple OSS Distributions };
69*aca3beaaSApple OSS Distributions 
70*aca3beaaSApple OSS Distributions #endif /* !_IOGUARDPAGEMEMORYDESCRIPTOR_H */
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