Tyler Dauwalder <tyler@xxxxxxxxxxxxx> wrote: > > > 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. Yes, I have the same problems with it - especially because there are only 4 primary partitions on the PC. But the advantages it bring cannot be achieved otherwise (at least I don't see a way). > > > 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=3F Or is that too much overhead to get at the > necessary data=3F I guess that also wouldn't allowing booting a RAID > partition, but... If that data would lie on the boot partition, you would not be able to resize or move that partition as well. And yes, RAID wouldn't be possible as well. > > > 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. No no! :-)) I don't plan to make it a requirement. And that's also because I don't like having a spare partition for this as well. The user can decide which way he wants to go, the system doesn't rely on anything :) If we don't do another file system for R2 (which could solve the problems more nicely), we would have the following options for R2: - leave it as is, the boot partition doesn't support any weird things, the partition resize/move journal would be placed on the boot partition as well, in a file. - have a spare partition that contains the journal - have a spare partition that contains the journal and the boot loader, enabling things like RAID/resize/move for the boot partition as well Without an extra partition, the boot partition could only be resized/ moved off-line, as with Windows :-) > > 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=3D5Fscanner > > module > > (I would rename it to something like disk=3D5Fdevice=3D5Fmanager) > disk=5Fdevice=5Fmanager works for me. :-) For me too. > > 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. > :-) Thanks! I am looking forward to this. > Done. I hope I didn't miss anything. Yell at me if I did. :-) > http://www.dauwalder.net/DiskDeviceAPI=5Fv2.2.zip Thanks to you too :) > > 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. With the option of setting the allowed size. Should be okay. Adios... Axel.