Filesystem

A filesystem is a representation of a files hierarchy on a storage device.

The following filesystems are natively supported:

• ext2: a common filesystem in UNIX environments. Now obsolete (to be replaced by ext4)

kernfs

A kernfs is a special kind of filesystem that do not store any information on any storage device. Its purpose is to provide a file interface to easily transmit information to the userspace.

Native kernfs kinds include:

• tmpfs: storage for temporary files on RAM
• procfs: provides information about processes
• sysfs: provides information about the system

Virtual FileSystem

The VFS is a filesystem that has no representation on any storage device. Rather, it is built from other filesystems that are assembled together to form the system’s files hierarchy.

Mounting a filesystem is the action of adding a filesystem to the VFS so that it becomes accessible to users.

The directory on which a filesystem is mounted is called a mountpoint.