diff options
| -rw-r--r-- | kvmd/apps/kvmd/msd.py | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/kvmd/apps/kvmd/msd.py b/kvmd/apps/kvmd/msd.py index 166a9cac..5f85662c 100644 --- a/kvmd/apps/kvmd/msd.py +++ b/kvmd/apps/kvmd/msd.py @@ -30,6 +30,7 @@ import dataclasses import types from typing import Dict +from typing import IO from typing import Callable from typing import Type from typing import AsyncGenerator @@ -145,15 +146,21 @@ def _parse_image_info_bytes(data: bytes) -> Optional[_ImageInfo]: return None +def _ioctl_uint32(device_file: IO, request: int) -> int: + buf = b"\0" * 4 + buf = fcntl.ioctl(device_file.fileno(), request, buf) + result = struct.unpack("I", buf)[0] + assert result > 0, (device_file, request, buf) + return result + + def _explore_device(device_path: str) -> _MassStorageDeviceInfo: if not stat.S_ISBLK(os.stat(device_path).st_mode): raise RuntimeError("Not a block device: %s" % (device_path)) with open(device_path, "rb") as device_file: - buf = b"\0" * 8 - buf = fcntl.ioctl(device_file.fileno(), 0x80081272, buf) # BLKGETSIZE64 - size = struct.unpack("L", buf)[0] - assert size > 0, (size, buf) + # size = BLKGETSIZE * BLKSSZGET + size = _ioctl_uint32(device_file, 0x1260) * _ioctl_uint32(device_file, 0x1268) device_file.seek(size - _IMAGE_INFO_SIZE) image_info = _parse_image_info_bytes(device_file.read()) |