diff options
| -rw-r--r-- | devices/src/virtio/block.rs | 28 | ||||
| -rw-r--r-- | src/linux.rs | 4 |
2 files changed, 24 insertions, 8 deletions
diff --git a/devices/src/virtio/block.rs b/devices/src/virtio/block.rs index 83616ce..ee4528b 100644 --- a/devices/src/virtio/block.rs +++ b/devices/src/virtio/block.rs @@ -28,6 +28,7 @@ const VIRTIO_BLK_S_OK: u8 = 0; const VIRTIO_BLK_S_IOERR: u8 = 1; const VIRTIO_BLK_S_UNSUPP: u8 = 2; +const VIRTIO_BLK_F_RO: u32 = 5; const VIRTIO_BLK_F_FLUSH: u32 = 9; pub trait DiskFile: Read + Seek + Write {} @@ -345,6 +346,7 @@ pub struct Block<T: DiskFile> { disk_image: Option<T>, config_space: Vec<u8>, avail_features: u64, + read_only: bool, } fn build_config_space(disk_size: u64) -> Vec<u8> { @@ -363,7 +365,7 @@ impl<T: DiskFile> Block<T> { /// Create a new virtio block device that operates on the given file. /// /// The given file must be seekable and sizable. - pub fn new(mut disk_image: T) -> SysResult<Block<T>> { + pub fn new(mut disk_image: T, read_only: bool) -> SysResult<Block<T>> { let disk_size = disk_image.seek(SeekFrom::End(0))? as u64; if disk_size % SECTOR_SIZE != 0 { warn!("Disk size {} is not a multiple of sector size {}; \ @@ -373,12 +375,16 @@ impl<T: DiskFile> Block<T> { } let mut avail_features: u64 = 1 << VIRTIO_BLK_F_FLUSH; + if read_only { + avail_features |= 1 << VIRTIO_BLK_F_RO; + } Ok(Block { kill_evt: None, disk_image: Some(disk_image), config_space: build_config_space(disk_size), avail_features, + read_only, }) } } @@ -489,7 +495,7 @@ mod tests { let f = File::create(&path).unwrap(); f.set_len(0x1000).unwrap(); - let b = Block::new(f).unwrap(); + let b = Block::new(f, true).unwrap(); let mut num_sectors = [0u8; 4]; b.read_config(0, &mut num_sectors); // size is 0x1000, so num_sectors is 8 (4096/512). @@ -506,10 +512,20 @@ mod tests { let mut path = PathBuf::from(tempdir.as_path().unwrap()); path.push("disk_image"); - let f = File::create(&path).unwrap(); - let b = Block::new(f).unwrap(); + // read-write block device + { + let f = File::create(&path).unwrap(); + let b = Block::new(f, false).unwrap(); + // writable device should just set VIRTIO_BLK_F_FLUSH + assert_eq!(0x200, b.features(0)); + } - // VIRTIO_BLK_F_FLUSH should always be set - assert_eq!(0x200, b.features(0)); + // read-only block device + { + let f = File::create(&path).unwrap(); + let b = Block::new(f, true).unwrap(); + // read-only device should set VIRTIO_BLK_F_FLUSH and VIRTIO_BLK_F_RO + assert_eq!(0x220, b.features(0)); + } } } diff --git a/src/linux.rs b/src/linux.rs index e3784f2..77eb2cb 100644 --- a/src/linux.rs +++ b/src/linux.rs @@ -419,13 +419,13 @@ fn setup_mmio_bus(cfg: &Config, let block_box: Box<devices::virtio::VirtioDevice> = match disk.disk_type { DiskType::FlatFile => { // Access as a raw block device. - Box::new(devices::virtio::Block::new(raw_image) + Box::new(devices::virtio::Block::new(raw_image, disk.read_only) .map_err(|e| Error::BlockDeviceNew(e))?) } DiskType::Qcow => { // Valid qcow header present let qcow_image = QcowFile::from(raw_image) .map_err(|e| Error::QcowDeviceCreate(e))?; - Box::new(devices::virtio::Block::new(qcow_image) + Box::new(devices::virtio::Block::new(qcow_image, disk.read_only) .map_err(|e| Error::BlockDeviceNew(e))?) } }; |