From: Keith Owens <kaos@sgi.com>
To: linux-xfs@oss.sgi.com
Subject: Mixed case support in XFS
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Date: Sat, 24 May 2003 00:17:30 +1000
Message-ID: <5312.1053699450@ocs3.intra.ocs.com.au>
Sender: linux-xfs-bounce@oss.sgi.com
Errors-to: linux-xfs-bounce@oss.sgi.com
Precedence: bulk
Content-Length: 1914
Lines: 51

Steve Lord <lord@sgi.com> wrote:
>	Mixed case support in XFS (for Samba)

Off the wall suggestion.  Instead of changing XFS to suit Samba, layer
another filesystem over XFS that converts all names to lower case and
provide that filesystem view to Samba.  Such a layered filesystem for
converting to lower case already exists, locasefs as part of the LUFS
package (lufs.sourceforge.net).

Pro:
  No XFS disk format changes.
  No XFS work at all :-))
  Works for all filesystems, not just XFS.

Con:
  Extra copies of the data (XFS -> LUFS -> SAMBA), acceptable when the
  network and/or the Windows machines are the bottleneck.


LUFS filesystems cannot be NFS exported yet, and I do not know if the
NFS restrictions on LUFS layers will affect Samba or not.  OTOH I have
a vested interest in making LUFS layers work over NFS so I expect that
problem to be solved fairly soon.


From the locasefs source comments:

  Use case:
    Win32 filesystem is basically case insensitive.

    Casing in file names is supported, but not relevant when opening
    files, a case insensitive matching is performed.  If working with
    source code obtained from win32 on *nix systems, you often have to
    manually convert into a lowercase-only tree to be safe

    Getting into a more complicated situation where the *nix version
    has to interoperate with the win32 source, without the ability to
    change all the casing to be correctly lowercase in the win32 master
    source.

  Objective:
    Provide a lowercase mapping of a filesystem (read/write).
  Discussion:
    There are probably several operating options, such as supporting a
    case-sensitive filesystem a-la-win32, mapping to uppercase, mapping
    to lowercase ..
  Implementation:
    get the lowercase mount as a flag over regular localfs?
    NOTE: what happens if root has something like: File and file in
    same dir? first found will be selected