reassign 634658 udev thanks
Hi! On BTRFS kernel mailing Karel Zak suggest to use udev rules in order to call btrfs device scan for multi volume BTRFS configurations. Calvin hinted at some udev rules that Dracut ships. Please consider adding udev rules to support RAID / multi volume configurations of BTRFS for booting. Note: This may still need a change in initramfs, as they command needs to be available at that time. Nonetheless I am reassigning to udev for now to bring this issue to the attention of the Debian udev package developers. Please feel free to reassign, when you think this should be fixed in btrfs- tools or somewhere else nonetheless. Maybe it also needs to be cloned if changes in more than one package are required. PS: The following two bug reports seem to be related, so mine is likely a duplicate of them - not merging yet, feel free to do so if you agree: btrfs-tools: add initramfs boot and hook scripts http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=559710 please provide non-initramfs-tools integration http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=585568 Thanks, Martin ---------- Weitergeleitete Nachricht ---------- Subject: Re: "Invalid argument" when mounting a btrfs raid1 filesystem Date: Montag, 26. März 2012 From: Calvin Walton <[email protected]> To: Karel Zak <[email protected]> On Mon, 2012-03-26 at 10:51 +0200, Karel Zak wrote: > On Sat, Mar 24, 2012 at 06:21:05PM +0000, Hugo Mills wrote: > > As Sadner says, you have to run "btrfs dev scan" before you try to > > mount the FS. If you have root on btrfs, this will have to go in an > > initrd; otherwise, it can go in your initscripts anywhere before the > > non-root filesystem mounts. > > > > Basically, the kernel needs to know which devices hold which btrfs > > filesystems (organised by UUID) before it tries to mount them. So, > > there's an ioctl that is used for sending that data to the kernel, and > > a userspace tool (btrfs dev scan) that enumerates all of the block > > devices it can see, looks for a btrfs superblock on them, and tells > > the kernel. > > Please, move all this logic to udev rules where we already scans all > devices. It's really bad to scan all device more than once. We spent > years to fix this problem for LVM, I don't think that btrfs has to > repeat the same mistakes. Oh, this is already possible to do with udev rules, quite easily. In fact, dracut ships with the appropriate udev rules, which it uses to initialize btrfs filesystems in the initramfs: http://git.kernel.org/?p=boot/dracut/dracut.git;a=blob;f=modules.d/90btrfs/80- btrfs.rules;hb=HEAD which would be suitable with minor modifications for use in a system udev installation as well. -- Calvin Walton <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html ------------------------------------------------------- -- Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7 -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
