MemoryDevice.cpp 1.8 KB

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  1. /*
  2. * Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
  3. *
  4. * SPDX-License-Identifier: BSD-2-Clause
  5. */
  6. #include <AK/Memory.h>
  7. #include <AK/StdLibExtras.h>
  8. #include <Kernel/Arch/PC/BIOS.h>
  9. #include <Kernel/Devices/MemoryDevice.h>
  10. #include <Kernel/Memory/AnonymousVMObject.h>
  11. #include <Kernel/Sections.h>
  12. namespace Kernel {
  13. UNMAP_AFTER_INIT NonnullRefPtr<MemoryDevice> MemoryDevice::must_create()
  14. {
  15. return adopt_ref(*new MemoryDevice);
  16. }
  17. UNMAP_AFTER_INIT MemoryDevice::MemoryDevice()
  18. : CharacterDevice(1, 1)
  19. {
  20. }
  21. UNMAP_AFTER_INIT MemoryDevice::~MemoryDevice()
  22. {
  23. }
  24. KResultOr<size_t> MemoryDevice::read(FileDescription&, u64, UserOrKernelBuffer&, size_t)
  25. {
  26. TODO();
  27. }
  28. void MemoryDevice::did_seek(FileDescription&, off_t)
  29. {
  30. TODO();
  31. }
  32. KResultOr<Memory::Region*> MemoryDevice::mmap(Process& process, FileDescription&, Memory::VirtualRange const& range, u64 offset, int prot, bool shared)
  33. {
  34. auto viewed_address = PhysicalAddress(offset);
  35. dbgln("MemoryDevice: Trying to mmap physical memory at {} for range of {} bytes", viewed_address, range.size());
  36. if (!MM.is_allowed_to_mmap_to_userspace(viewed_address, range)) {
  37. dbgln("MemoryDevice: Trying to mmap physical memory at {} for range of {} bytes failed due to violation of access", viewed_address, range.size());
  38. return EINVAL;
  39. }
  40. auto maybe_vmobject = Memory::AnonymousVMObject::try_create_for_physical_range(viewed_address, range.size());
  41. if (maybe_vmobject.is_error())
  42. return maybe_vmobject.error();
  43. dbgln("MemoryDevice: Mapped physical memory at {} for range of {} bytes", viewed_address, range.size());
  44. return process.address_space().allocate_region_with_vmobject(
  45. range,
  46. maybe_vmobject.release_value(),
  47. 0,
  48. "Mapped Physical Memory",
  49. prot,
  50. shared);
  51. }
  52. }