[RFC 0/2] e2fsprogs: Add FUSE server

["Darrick J. Wong" <djwong@us.ibm.com>]

Hi all,

This patchset creates a FUSE server for the ext4 filesystem.  This enables ext4
to be run (albeit slowly) in environments which lack a native ext4 driver, such
as Solaris, BSD, and Mac OS X.  It uses the functionality in libext2fs to
manipulate the filesystem.

Currently, the filesystem can be mounted for both reading and writing.  I
wouldn't mount a production filesystem rw, though in my nail-biting tests so
far it hasn't destroyed anything.  Journalling is not supported, though I'm
working on at least enabling journal replay on mount.  I suspect that full
journalling (such as what you get with kernel ext4 on Linux) is a long way off.

The performance of fuse2fs (as opposed to kernel ext4) is noticeably slow.

This patchset has been tested on 3.1 on x64 and i386, and Mac OS X.  On Linux
you'll need a libfuse that supports the v28 API; on Mac you'll need osxfuse
2.3.8.  The patchset is based atop the 1.42 release and requires three patches:

1. libext2fs: Read and write full size inodes
2. libext2fs: When truncating file, punch out blocks at end
3. libext2fs: Only link an inode into a directory once

The first patch is in the metadata checksumming set, and the other two are
general bugfixes that I posted earlier.

Let me know what you think!

--D