| 1 | /*++ |
| 2 | |
| 3 | Copyright (c) Microsoft. All rights reserved. |
| 4 | |
| 5 | Module Name: |
| 6 | |
| 7 | WslCoreFilesystem.cpp |
| 8 | |
| 9 | Abstract: |
| 10 | |
| 11 | This file contains filesystem helper function definitions. |
| 12 | |
| 13 | --*/ |
| 14 | |
| 15 | #include "precomp.h" |
| 16 | #include "WslCoreFilesystem.h" |
| 17 | #include "WslSecurity.h" |
| 18 | |
| 19 | wil::unique_hfile wsl::core::filesystem::CreateFile( |
| 20 | _In_ LPCWSTR fileName, _In_ DWORD desiredAccess, _In_ DWORD shareMode, _In_ DWORD creationDisposition, _In_ DWORD flagsAndAttributes, _In_ PSID userSid) |
| 21 | { |
| 22 | auto sd = windows::common::security::CreateSecurityDescriptor(userSid); |
| 23 | SECURITY_ATTRIBUTES sa{sizeof(SECURITY_ATTRIBUTES), &sd, false}; |
| 24 | wil::unique_hfile file{CreateFileW(fileName, desiredAccess, shareMode, &sa, creationDisposition, flagsAndAttributes, nullptr)}; |
| 25 | THROW_LAST_ERROR_IF(!file); |
| 26 | |
| 27 | return file; |
| 28 | } |
| 29 | |
| 30 | void wsl::core::filesystem::CreateVhd(_In_ LPCWSTR target, _In_ ULONGLONG maximumSize, _In_ PSID userSid, _In_ BOOL sparse, _In_ BOOL fixed) |
| 31 | { |
| 32 | THROW_HR_IF( |
| 33 | E_INVALIDARG, |
| 34 | !wsl::windows::common::string::IsPathComponentEqual( |
| 35 | std::filesystem::path{target}.extension().native(), windows::common::wslutil::c_vhdxFileExtension)); |
| 36 | |
| 37 | // Disable creation of sparse VHDs while data corruption is being debugged. |
| 38 | if (sparse) |
| 39 | { |
| 40 | sparse = false; |
| 41 | EMIT_USER_WARNING(wsl::shared::Localization::MessageSparseVhdDisabled()); |
| 42 | } |
| 43 | |
| 44 | VIRTUAL_STORAGE_TYPE storageType{}; |
| 45 | storageType.DeviceId = VIRTUAL_STORAGE_TYPE_DEVICE_VHDX; |
| 46 | storageType.VendorId = VIRTUAL_STORAGE_TYPE_VENDOR_MICROSOFT; |
| 47 | |
| 48 | // Create a VHDX with the specified maximum size. |
| 49 | // |
| 50 | // N.B. The block size was chosen based on the best practices for Linux VHDs: |
| 51 | // https://docs.microsoft.com/en-us/windows-server/virtualization/hyper-v/best-practices-for-running-linux-on-hyper-v |
| 52 | CREATE_VIRTUAL_DISK_PARAMETERS createVhdParameters{}; |
| 53 | createVhdParameters.Version = CREATE_VIRTUAL_DISK_VERSION_2; |
| 54 | createVhdParameters.Version2.BlockSizeInBytes = _1MB; |
| 55 | createVhdParameters.Version2.MaximumSize = maximumSize; |
| 56 | |
| 57 | CREATE_VIRTUAL_DISK_FLAG flags = CREATE_VIRTUAL_DISK_FLAG_SUPPORT_COMPRESSED_VOLUMES; |
| 58 | WI_SetFlagIf(flags, CREATE_VIRTUAL_DISK_FLAG_FULL_PHYSICAL_ALLOCATION, fixed); |
| 59 | if (sparse) |
| 60 | { |
| 61 | WI_SetAllFlags(flags, CREATE_VIRTUAL_DISK_FLAG_SPARSE_FILE | CREATE_VIRTUAL_DISK_FLAG_SUPPORT_SPARSE_FILES_ANY_FS); |
| 62 | } |
| 63 | |
| 64 | // Explicitly set the owner of the file so the default is not used. |
| 65 | // |
| 66 | // N.B. This ensures that HcsGrantVmAccess is able to add the required ACL |
| 67 | // to the VHD because the operation is done while impersonating the user. |
| 68 | auto sd = windows::common::security::CreateSecurityDescriptor(userSid); |
| 69 | |
| 70 | wil::unique_hfile vhd{}; |
| 71 | auto result = HRESULT_FROM_WIN32( |
| 72 | ::CreateVirtualDisk(&storageType, target, VIRTUAL_DISK_ACCESS_NONE, &sd, flags, 0, &createVhdParameters, nullptr, &vhd)); |
| 73 | if (FAILED(result)) |
| 74 | { |
| 75 | THROW_HR_WITH_USER_ERROR( |
| 76 | result, shared::Localization::MessageFailedToCreateDisk(target, windows::common::wslutil::GetErrorString(result))); |
| 77 | } |
| 78 | } |
| 79 | |
| 80 | wil::unique_handle wsl::core::filesystem::OpenVhd(_In_ LPCWSTR Path, _In_ VIRTUAL_DISK_ACCESS_MASK Mask) |
| 81 | { |
| 82 | WI_ASSERT(wsl::windows::common::wslutil::IsVhdFile(std::filesystem::path{Path})); |
| 83 | |
| 84 | // N.B. Specifying unknown for device and vendor means the system will determine the type of VHD. |
| 85 | VIRTUAL_STORAGE_TYPE storageType{}; |
| 86 | storageType.DeviceId = VIRTUAL_STORAGE_TYPE_DEVICE_UNKNOWN; |
| 87 | storageType.VendorId = VIRTUAL_STORAGE_TYPE_VENDOR_UNKNOWN; |
| 88 | |
| 89 | wil::unique_handle disk; |
| 90 | THROW_IF_WIN32_ERROR(OpenVirtualDisk(&storageType, Path, Mask, OPEN_VIRTUAL_DISK_FLAG_NONE, nullptr, &disk)); |
| 91 | |
| 92 | return disk; |
| 93 | } |
| 94 | |
| 95 | void wsl::core::filesystem::CompactVhd(_In_ LPCWSTR Path) |
| 96 | { |
| 97 | auto diskHandle = OpenVhd(Path, VIRTUAL_DISK_ACCESS_GET_INFO | VIRTUAL_DISK_ACCESS_METAOPS); |
| 98 | |
| 99 | COMPACT_VIRTUAL_DISK_PARAMETERS compact{}; |
| 100 | compact.Version = COMPACT_VIRTUAL_DISK_VERSION_1; |
| 101 | |
| 102 | THROW_IF_WIN32_ERROR(CompactVirtualDisk(diskHandle.get(), COMPACT_VIRTUAL_DISK_FLAG_NONE, &compact, nullptr)); |
| 103 | } |
| 104 | |
| 105 | void wsl::core::filesystem::ResizeExistingVhd(_In_ HANDLE diskHandle, _In_ ULONGLONG maximumSize, _In_ RESIZE_VIRTUAL_DISK_FLAG resizeFlag) |
| 106 | { |
| 107 | RESIZE_VIRTUAL_DISK_PARAMETERS resize{}; |
| 108 | resize.Version1.NewSize = maximumSize; |
| 109 | resize.Version = RESIZE_VIRTUAL_DISK_VERSION_1; |
| 110 | THROW_IF_WIN32_ERROR(ResizeVirtualDisk(diskHandle, resizeFlag, &resize, nullptr)); |
| 111 | } |
| 112 | |
| 113 | ULONGLONG wsl::core::filesystem::GetDiskSize(_In_ HANDLE diskHandle) |
| 114 | { |
| 115 | GET_VIRTUAL_DISK_INFO virtualDiskInfo{}; |
| 116 | virtualDiskInfo.Version = GET_VIRTUAL_DISK_INFO_SIZE; |
| 117 | ULONG size = sizeof(virtualDiskInfo); |
| 118 | |
| 119 | THROW_IF_WIN32_ERROR(GetVirtualDiskInformation(diskHandle, &size, &virtualDiskInfo, nullptr)); |
| 120 | |
| 121 | return virtualDiskInfo.Size.VirtualSize; |
| 122 | } |