The Linux Kernel Device Mapper is the LVM (Linux Logical Volume Management)
 Team's implementation of a minimalistic kernel-space driver that handles
 volume management, while keeping knowledge of the underlying device layout
 in user-space. This makes it useful for not only LVM, but software raid,
 and other drivers that create "virtual" block devices.
 .
 This package contains the userspace library to help with event monitoring
 for devmapper devices, in conjunction with the dmevent daemon.