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28 #ifndef __MEM_BACKDOOR_HH__
29 #define __MEM_BACKDOOR_HH__
35 #include "base/addr_range.hh"
36 #include "base/callback.hh"
41 // Callbacks from this back door are set up using a callable which accepts
42 // a const reference to this back door as their only parameter.
43 typedef std::function<void(const MemBackdoor &backdoor)> CbFunction;
47 // How data is allowed to be accessed through this backdoor.
53 // The range in the guest address space covered by this back door.
54 const AddrRange &range() const { return _range; }
55 void range(const AddrRange &r) { _range = r; }
57 // A pointer to the data accessible through this back door.
58 uint8_t *ptr() const { return _ptr; }
59 void ptr(uint8_t *p) { _ptr = p; }
62 * Helper functions to make it easier to set/check particular flags.
65 bool readable() const { return _flags & Readable; }
70 _flags = (Flags)(_flags | Readable);
72 _flags = (Flags)(_flags & ~Readable);
75 bool writeable() const { return _flags & Writeable; }
80 _flags = (Flags)(_flags | Writeable);
82 _flags = (Flags)(_flags & ~Writeable);
85 Flags flags() const { return _flags; }
86 void flags(Flags f) { _flags = f; }
88 MemBackdoor(AddrRange r, uint8_t *p, Flags flags) :
89 _range(r), _ptr(p), _flags(flags)
92 MemBackdoor() : MemBackdoor(AddrRange(), nullptr, NoAccess)
95 // Set up a callable to be called when this back door is invalidated. This
96 // lets holders update their bookkeeping to remove any references to it,
97 // and/or to propogate that invalidation to other interested parties.
99 addInvalidationCallback(CbFunction func)
101 invalidationCallbacks.push_back([this,func](){ func(*this); });
104 // Notify and clear invalidation callbacks when the data in the backdoor
105 // structure is no longer valid/current. The backdoor might then be
106 // updated or even deleted without having to worry about stale data being
111 invalidationCallbacks.process();
112 invalidationCallbacks.clear();
116 CallbackQueue invalidationCallbacks;
123 typedef MemBackdoor *MemBackdoorPtr;
125 #endif //__MEM_BACKDOOR_HH__