On Mon, May 31, 2004 at 09:18:40PM +0200, David Zeuthen wrote: > > If it works sure. Ultimately I'd like to find a clean way to do a volumagic > > like thing with the I/O layer in kernel space. Let the daemon do handle > > translations and let the kernel do the I/O paths > > Wouldn't it suffice with just an option to mount(1), e.g. have as few > changes to how this impact user space as possible. I mean, at the end of > the day, isn't this just about the kernel locking/unlocking the drive > (same for e.g. USB storage) only when there is I/O? To do it properly you need a bit more because users may change CD-ROMs and you probably want to do "Please insert 'Install Disk 2'" type dialogs. Internally the kernel really doesn't deal with disks going away when they are wanted. Volumagic can cope with cd /mnt/cdrom eject insert new cd ls and also with requests when the disk is removed - not all file systems handle media vanishing as a routine thing. Stephen Tweedie had some 2.2 patches "supermount" which tried to address this whole thing properly and while there have been 2.4 and 2.6 attempts I've not seen one that addresses it all cleanly.
