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. Userland NOTE: new umsdos_progs (umssync, umssetup, udosctl & friends) that will compile and work on 2.2.x kernels and glibc based systems may be found at http://cvs.linux.hr/ Also look at the quick-hack "homepage" for umsdos filesystem at http://www.voyager.hr/~mnalis/umsdos Information below is getting outdated slowly -- I'll fix it one day when I get enough time - there are more important things to fix right now. 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 (990202) - UMSDOS 0.85: (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 + 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 may be some problems. Volunteers ready to test pseudoroot are needed (preferably ones with working backups or unimportant data). For example, '/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! Note: (about creating hardlinks in pseudoroot mode) - hardlinks created in pseudoroot mode are now again compatibile with 'normal' hardlinks, and vice versa. Thanks to Sorin Iordachescu for providing fix. Warning: (about hardlinks) - modifying hardlinks (esp. if they are in different directories) are currently somewhat broken, I'm working on it. Problem seems to be that code uses and updates EMD of directory where 'real hardlink' is stored, not EMD of directory where our pseudo-hardlink is located! I'm looking for ideas how to work around this in clean way, since without it modifying hardlinks in any but most simple ways is broken! ------------------------------------------------------------------------------ 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.