Struct MountedImageRoot 

pub(crate) struct MountedImageRoot {
    _esp: MountGuard,
    _tmp: MountGuard,
    composefs: TempMount,
    pub(crate) esp_subdir: &'static str,
}

A composefs image attached to a temporary directory with the ESP and a tmpfs mounted inside it, ready for bootloader installation.

The composefs image (a detached fsmount(2) fd with no VFS path) is attached to a tmpdir via move_mount(2), giving us a real filesystem path that mount(2) and bootctl can use. The ESP is mounted at <tmpdir>/efi (if that directory exists in the image) or <tmpdir>/boot, per the Boot Loader Specification. A tmpfs is also mounted at <tmpdir>/tmp to provide a writable scratch area for tools invoked with --root.

Drop order matters: the ESP and tmpfs guards are declared before composefs so they are unmounted (and flushed) before the composefs root is detached.

Fields

_esp: MountGuard

_tmp: MountGuard

composefs: TempMount

esp_subdir: &'static str

Implementations

impl MountedImageRoot

pub(crate) fn new(composefs_mnt_fd: OwnedFd, device: &Device) -> Result<Self>

Find the ESP on device, attach the composefs image to a tmpdir, and mount the ESP and a scratch tmpfs inside it.

pub(crate) fn dir(&self) -> &Dir

The composefs image as a capability-safe directory (for file reads).

pub(crate) fn root_path(&self) -> &Path

Real filesystem path of the composefs tmpdir root.

pub(crate) fn open_esp_dir(&self) -> Result<Dir>

Open the mounted ESP as a capability-safe directory.