On Thu, Jan 13, 2011 at 12:26:14PM +0100, Milan Broz wrote: > On 01/13/2011 12:06 PM, Tejun Heo wrote: > > Urgh... gees, so there actually was a user using all that cruft. > > Sorry about the breakage, I'll see how multiple symlinks can be > > restored. I'm curious why this was added at all tho. What was the > > rationalization? It's not like two subsystems can share the same > > block device so marking the currently owning subsystem should have > > been enough at the block layer. There is no reason for block devices > > to present information which is of no use to itself. All that's > > necessary is "this is taken by dm or md for more information, query > > those". dm and md need their own conf/representation layer anyway. > > I am not sure if I understand it correctly, but multiple holders/slaves > links are very useful in userspace to present device dependences. > > We just implemented lsblk command in util-linux which simple prints > tree according to these links, so dependendes of DM/MD/whatever devices > can be printed without using any system specific callbacks, just using > sysfs. See http://karelzak.blogspot.com/2010/12/lsblk8.html We also use holders/slaves links in libblkid to evaluate dependencies between devices (since 2008). > Whatever changes are needed, please keep this functionality, it can be useful. Definitely. Karel -- Karel Zak <kzak@xxxxxxxxxx> http://karelzak.blogspot.com -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
