Changes by Matija Nalis (mnalis@jagor.srce.hr) on umsdos dentry fixing (started by Peter T. Waltenberg ) (Final conversion to dentries Bill Hawes ) There is no warning any more. Both read-only and read-write stuff is fixed, both in msdos-compatibile mode, and in umsdos EMD mode, and it seems stable. There are still few hardlink nuisances, but those are not fatal. I'd call it pre-release, and ask for as many people as possible to come and test it! See notes below for some more information, or if you are trying to use UMSDOS as root partition. Legend: those lines marked with '+' on the beggining of line indicates it passed all of my tests, and performed perfect in all of them. Current status (981129) - UMSDOS dentry-pre 0.84: (1) pure MSDOS (no --linux-.--- EMD file): READ: + readdir - works + lookup - works + read file - works WRITE: + creat file - works + delete file - works + write file - works + rename file (same dir) - works + rename file (dif. dir) - works + rename dir (same dir) - works + rename dir (dif. dir) - works + mkdir - works + rmdir - works (2) umsdos (with --linux-.--- EMD file): READ: + readdir - works + lookup - works + permissions/owners stuff - works + long file names - works + read file - works + switching MSDOS/UMSDOS - works + switching UMSDOS/MSDOS - works - pseudo root things - works mostly. See notes below. + resolve symlink - works + dereference symlink - works + dangling symlink - works + hard links - works + special files (block/char devices, FIFOs, sockets...) - works + various umsdos ioctls - works WRITE: + create symlink - works - create hardlink - works, but see portability WARNING below + create file - works + create special file - works + write to file - works + rename file (same dir) - works + rename file (dif. dir) - works - rename hardlink (same dir) - - rename hardlink (dif. dir) - + rename symlink (same dir) - works + rename symlink (dif. dir) - works + rename dir (same dir) - works + rename dir (dif. dir) - works + delete file - works + notify_change (chown,perms) - works + delete hardlink - works + mkdir - works + rmdir - works + umssyncing (many ioctls) - works - CVF-FAT stuff (compressed DOS filesystem) - there is some support from Frank Gockel to use it even under umsdosfs, but I have no way of testing it -- please let me know if there are problems specific to umsdos (for instance, it works under msdosfs, but not under umsdosfs). Some current notes: Note: creating and using pseudo-hardlinks is always non-perfect, especially in filesystems that might be externally modified like umsdos. There is example is specs file about it. Specifically, moving directory which contains hardlinks will break them. Note: (about pseudoroot) If you are currently trying to use UMSDOS as root partition (with linux installed in c:\linux) it will boot, but there are some problems. Volunteers ready to test pseudoroot are needed (preferably ones with working backups or unimportant data). There are problems with different interpretation of hard links in normal in pseudo-root modes, resulting is 'silent delete' of them sometimes. Also, '/DOS' pseudo directory is only partially re-implemented and buggy. It works most of the time, though. Update: should work ok in 0.84, although it still does not work correctly in combination with initrd featere. Working on this! Warning: (about creating hardlinks in pseudoroot mode) - hardlinks created in pseudoroot mode are not compatibile with 'normal' hardlinks, and vice versa. That is because harlink which is /foo in pseudoroot mode, becomes /linux/foo in normal mode. I'm thinking about this one. However, since most people either always use pseudoroot, or always use normal umsdos filesystem, this is no showstopper. Warning: (about hardlinks) - modifying hardlinks (esp. if there are in different directories) are currently somewhat broken, I'm working on it. ------------------------------------------------------------------------------ Some general notes: Good idea when running development kernels is to have SysRq support compiled in kernel, and use Sync/Emergency-remount-RO if you bump into problems (like not being able to umount(2) umsdosfs, and because of it root partition also, or panics which force you to reboot etc.) I'm unfortunately somewhat out of time to read linux-kernel@vger, but I do check for messages having "UMSDOS" in the subject, and read them. I might miss some in all that volume, though. I should reply to any direct e-mail in few days. If I don't, probably I never got your message. You can try mnalis-umsdos@voyager.hr; however mnalis@jagor.srce.hr is preferable.