On Tuesday 12 February 2008, David Miller wrote: > From: David Miller <davem@xxxxxxxxxxxxx> > Date: Mon, 11 Feb 2008 23:21:39 -0800 (PST) > > > Filesystems like ext2 put their superblock 1 block into the partition > > in order to avoid overwriting disk labels and other uglies. UFS does > > this too, as do several others. One of the few exceptions I've been > > able to find is XFS. > > > > This is a real issue on sparc where the default sun disk labels > > created use an initial partition where block zero aliases the disk > > label. It took me a few iterations before I figured out why every > > btrfs make would zero out my disk label :-/ > > Actually it seems this is only a problem with mkfs.btrfs, it clears > out the first 64 4K chunks of the disk for whatever reason. It is a good idea to remove supers from other filesystems. I also need to add zeroing at the end of the device as well. Looks like I misread the e2fs zeroing code. It zeros the whole external log device, and I assumed it also zero'd out the start of the main FS. So, if Btrfs starts zeroing at 1k, will that be acceptable for you? -chris - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
