On 2003-04-04 at 10:28:34 [-0800], Ingo Weinhold wrote: > > "Axel D=F6rfler" <axeld@xxxxxxxxxxxxxxxx> wrote: > > > > "Ingo Weinhold" <bonefish@xxxxxxxxxxxxxxx> wrote: > > > > The main motivation is that it gives the partition code a chance > > > > to > > > > declare what regions of unused space are valid for creating > > > > child > > > > partitions. > > > This might indeed be a good idea. Since the systems have some > > > administrative overhead (the PTSs in the intel system), it could > > > be > > > quite convenient. > > > > We will also need some kind of overhead or better a spare partition > > for > > the partition meta data in R2. That includes things like how the > > partitions have to be mapped during a move operation, but also > > informations about the RAID setup or similar things. > > I like that idea. Initially, I'd say I don't like the idea. However, I mostly just don't like the messiness of having an extra partition floating around. For example, I hate having to make separate linux swap partitions. But that's just a personal dislike. That being said, I recognize the advantages it could bring. > > It probably won't be possible to write this information down to an > > existing file system. > > Right. My one question is, couldn't a special file referenced from the BFS superblock be used? Or is that too much overhead to get at the necessary data? I guess that also wouldn't allowing booting a RAID partition, but... > > We could then also place the boot loader in that extra partition, so > > that the boot partition is free of any file system requirements (and > > could itself be located on a RAID partition) :-) > > Wouldn't that be a good idea even for R1. I mean, then there wouldn't > be the need to squeeze rudimentary BFS support into the boot block. If we go with a metadata partition, I'd just as soon make it a requirement from R1 on. > > Could you make a list of what kind of functionality the kernel > > module > > should contain and how it should be accessed from userland=3D3F > > Roughly, for the partition modules, it should be more or less the same > as it is now, plus a function per BDiskSystem method (or one function > for all of them). Userland access via syscall. The disk=5Fscanner > module > (I would rename it to something like disk=5Fdevice=5Fmanager) disk_device_manager works for me. :-) > would > need to > be extended vastly. It would incorporate the functionality currently > implemented in the registrar, plus support for locking, managing jobs > and the like. > > I'd like to write up a design draft for that part, so that we have > something more concrete to discuss about. Great! I was about to bring that up, but now I can sit back and relax. :-) > Tyler, could you please > update the 2.0 API according to the changes discussed over the past > days. That should make it a bit easier for me to work with it. If you > don't have time, just give a yell; the old one together with the mails > will do then. Done. I hope I didn't miss anything. Yell at me if I did. :-) http://www.dauwalder.net/DiskDeviceAPI_v2.2.zip > [...] > > > > Sounds good, though should ValidateInitialize include an off=3D > > > > 3D5Ft * > > > > size > > > > as > > > > well=3D3D3F > > > To return the size the system would actually use, so that the > > > caller > > > is > > > e.g. able to warn the user, if space would be wasted when trying > > > to > > > initialize the partition with a FS with a smaller maximal > > > size=3D3D3F > > > > Dunno if that's necessary. > > It would make more sense to set the minimum size the file system > > supports there (if the provided size is smaller) :-) > > Either one could be returned, depending on whether the partition is > too > small or too large. But let's listen to what Tyler originally intended > it for. :-) I intended it for general size bounds checking. So too small, too big, etc. -Tyler