Subject: Re: msdosfs directory bug -- any helpers out there?
To: None <current-users@netbsd.org>
From: Christos Zoulas <christos@astron.com>
List: current-users
Date: 11/02/2005 03:52:59
In article <200511020321.jA23LV3M018261@lothlorien.nfbcal.org>,
Brian Buhrow <buhrow@lothlorien.nfbcal.org> wrote:
>	Hello.   I'm running NetBSD-2.0/I386 on a machine, and using the msdos
>filesystem on a CF card which I use in a portable MP3 player.  I have traced
>a directory coruption problem down to NetBSD, but I could use a little
>advice on how to further isolate the problem and fix the bug.
>
>	The problem seems to have to do with the insertion and deletion of
>directory entries.  Although this activity seems to work fine with respect
>to using files under NetBSD and Windows XP, the little MP3 player keeps
>complaining of corrupt directories and files when those directories are
>manipulated by NetBSD, but doesn't complain when Windows XP manipulates the
>same directories.
>
>	The problem seems to crop up if I put files into a directory, remove
>some, and then add more files to that directory.  It's as if NetBSD doesn't
>completely clean up the directory from the MP3 player's perspective, but
>Windows does.
>
>	I've got a kernel built with options MSDOSFS_DEBUG enabled, and have
>been excercising a DOS filesystem, but at am a little loss as to where to
>look.  It looks like the createde() and removede() functions are promising
>places to begin, but I wondered if anyone else had any ideas.
>
>	Some questions off the top of my head, to begin with.
>
>1.  Has anyone else seen strange behavior when getting their portable
>devices to read msdos filesystems maintained by NetBSD?
>
>2. If so, did you find any work arounds?
>
>3.  Are there any known obvious differences between the way NetBSD and
>Windows leave directory entries after they're created or deleted?  Does
>windows clear the attributes field in a deleted directory entry, for
>example, while NetBSD does not?
>
>	I am happy to work on this problem, if someone is willing to provide
>advice and suggestions on the finer points of msdos filesystem semantics.
>Otherwise, any help would be greatly appreciatd.

I have not seen a problem like. Does the netbsd fsck_msdos find the corruption?

christos