30 
  31 // On macOS, we use a virtual backing file. It is represented by a reserved virtual
  32 // address space, in which we commit physical memory using the mach_vm_map() API.
  33 // The multi-mapping API simply remaps these addresses using mach_vm_remap() into
  34 // the different heap views. This works as-if there was a backing file, it's just
  35 // that the file is represented with memory mappings instead.
  36 
  37 class ZBackingFile {
  38 private:
  39   uintptr_t _base;
  40   size_t    _size;
  41   bool      _initialized;
  42 
  43   bool commit_inner(size_t offset, size_t length);
  44 
  45 public:
  46   ZBackingFile();
  47 
  48   bool is_initialized() const;
  49 


  50   size_t size() const;
  51 
  52   size_t commit(size_t offset, size_t length);
  53   size_t uncommit(size_t offset, size_t length);
  54 
  55   void map(uintptr_t addr, size_t size, uintptr_t offset) const;
  56   void unmap(uintptr_t addr, size_t size) const;
  57 };
  58 
  59 #endif // OS_BSD_GC_Z_ZBACKINGFILE_BSD_HPP

  30 
  31 // On macOS, we use a virtual backing file. It is represented by a reserved virtual
  32 // address space, in which we commit physical memory using the mach_vm_map() API.
  33 // The multi-mapping API simply remaps these addresses using mach_vm_remap() into
  34 // the different heap views. This works as-if there was a backing file, it's just
  35 // that the file is represented with memory mappings instead.
  36 
  37 class ZBackingFile {
  38 private:
  39   uintptr_t _base;
  40   size_t    _size;
  41   bool      _initialized;
  42 
  43   bool commit_inner(size_t offset, size_t length);
  44 
  45 public:
  46   ZBackingFile();
  47 
  48   bool is_initialized() const;
  49 
  50   void warn_commit_limits(size_t max) const;
  51 
  52   size_t size() const;
  53 
  54   size_t commit(size_t offset, size_t length);
  55   size_t uncommit(size_t offset, size_t length);
  56 
  57   void map(uintptr_t addr, size_t size, uintptr_t offset) const;
  58   void unmap(uintptr_t addr, size_t size) const;
  59 };
  60 
  61 #endif // OS_BSD_GC_Z_ZBACKINGFILE_BSD_HPP