tarfs is a tar file system implementation for FreeBSD. The current goals are:

• Support all standard read-only operations, just like a real file system.
• Support large tar files (several gb’s)
• Use minimal memory
• Allow using tar file as a root file system
• Fast enough to actually use

Here’s the current state of things:

• Mounts tar files (after using mdconfig to create a device)
• Can do most operations on the fs
• Supports large tar files
• Uses a relatively small amount of memory - proportional to number of files/dirs
• Fairly fast

Here’s the current issues still needing resolution:

• No ‘..’ directory in root of mounted tar file system
• Locking issues regarding ‘..’ in subdirs off root of fs
• No block/char special device support. Needed?
• Needs a directory cache (like dirhash maybe?)
• Have not yet tried as a root fs

Snapshot of the current code can be found here: tarfs-2008-01-20.tar.gz