Function write_boot_simple 

pub fn write_boot_simple<ObjectID: FsVerityHashValue>(
    repo: &Repository<ObjectID>,
    entry: BootEntry<ObjectID>,
    karg: &ComposefsCmdline<ObjectID>,
    boot_partition: &Path,
    boot_subdir: Option<&str>,
    entry_id: Option<&str>,
    cmdline_extra: &[&str],
) -> Result<()>

Writes boot entry to the boot partition

Arguments

• repo - The composefs repository
• entry - Boot entry variant to be written
• karg - The composefs kernel argument (encodes format version, digest, and insecure flag); used to build the composefs= or composefs.digest= cmdline argument
• boot_partition - Path to the boot partition/directory
• boot_subdir - If Some(path), the path is prepended to initrd and linux keys in the BLS entry

For example, if boot_partition = "/boot" and boot_subdir = Some("1") , the BLS entry will contain

linux /boot/1/<entry_id>/linux
initrd /boot/1/<entry_id>/initrd

If boot_partition = "/boot" and boot_subdir = None , the BLS entry will contain

linux /<entry_id>/linux
initrd /<entry_id>/initrd

• entry_id - In case of a BLS entry, the name of file to be generated in loader/entries
• cmdline_extra - Extra kernel command line arguments