Constant ENV_MOUNTS 

pub const ENV_MOUNTS: &str = "MSB_MOUNTS";

Environment variable carrying virtiofs volume mount specs for guest init.

Format: tag:guest_path[:ro][;tag:guest_path[:ro];...]

• tag — virtiofs tag name (required, matches the tag used in --mount)
• guest_path — mount point inside the guest (required)
• ro — mount read-only (optional suffix)

Entries are separated by ;.

Examples:

• MSB_MOUNTS=data:/data — mount virtiofs tag data at /data
• MSB_MOUNTS=data:/data:ro — mount read-only
• MSB_MOUNTS=data:/data;cache:/cache:ro — two mounts