On lun., 2011-10-17 at 13:15 -0400, markw@xxxxxxxxxxxxxx wrote: > Is it possible to get a list of extents mapped to an object from an ioctl > call? > > The reason why I am asking is that I need to be able to calculate the > deltas between a snapshot and a real device. For instance: > > Suppose I have a virtual machine on device /dev/lvmvol/vmserver. I create > a snapshot of that device named /dev/lvmvol/vmsnap. > > If I could get a list of the extents used to constitute "vmserver" and the > extents that constitute "vmsnap" I could calculate how much has changed > and what ranges I need to actually backup. Obviously, there has to be some > way to map "extents" to locations on the device itself in order for this > to work. > > I have looked in the dm code and can not see if this is possible. > The ddsnap tool might fit your need. It is hosted on the git space of http://www.opensvc.com Regards, cvaroqui -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
