storagemanager manages disks, partitions and volumes.
It discovers storage regions, announces available volumes and coordinates their use by filesystem drivers.
It handles mount, unmount, flush and filesystem-information requests through libstorage.
It validates partition layouts and boot space, manages partition changes and wiping, and coordinates formatting and boot-code installation. Disk reservations keep these operations from conflicting with mounted filesystems or other storage work.
A volume is a storage region that can contain a filesystem: a partition or an entire unpartitioned disk. Disk IDs come from device manager; volume IDs identify regions for the current boot.
Shutdown stops admission of new administrative jobs and controls, then waits for accepted work to finish before storage services are quiesced. Queries and ownership messages remain available while work drains. Cancellation restores admission; uncertain I/O prevents shutdown readiness.
The disk and volume tools use it for storage administration.
The Ghost installer uses it to prepare its destination and install boot code.
Filesystem drivers handle formatting and file access.