On Tue, 2016-02-02 at 15:06 -0700, Jim Fehlig wrote: > > > And extending > > the structure seems to be the right thing to do. > > So what do you think of the approach in the RFC patch? It adds discrete knobs > in > the disk config and extends the disk structure similarly. Before I can make > progress on this we need to agree on extending the config and > libxl_device_disk > structure.
My main concern is that this approach requires us to update libxl for each new possible backend type. The intention of the target= in the disk spec is that it consumes the rest of the line so it can be used to encode pretty much anything. Is it not possible (modulo bugs) to pass all the necessary information to qdisk in this form? I thought Dave S had made it possible to use qdisk in this way back in: commit a8a1f236a2964506a22d1779648d8e1c8668cb1a Author: David Scott < dave.sc...@eu.citrix.com > Date: Tue Apr 23 10:59:26 2013 +0100 libxl: Only call stat() when adding a disk if we expect a device to exist. We consider calling stat() a helpful error check in the following circumstances only: 1. the disk backend type must be PHYsical 2. the disk backend domain must be the same as the running libxl code (ie LIBXL_TOOLSTACK_DOMID) 3. there must not be a hotplug script because this would imply that the device won't be created until after the hotplug script has run. With this fix, it is possible to use qemu's built-in block drivers such as ceph/rbd, with a xl config disk spec like this: disk=[ 'backendtype=qdisk,format=raw,vdev=hda,access=rw,target=rbd:rbd/ubuntu1204.img' ] Signed-off-by: David Scott < dave.sc...@eu.citrix.com > Acked-by: Ian Campbell < ian.campb...@citrix.com > Acked-by: Roger Pau Monné < roger....@citrix.com > Of course things may have regressed again since then. Since target is basically passed as is to qdisk does libvirt not already have some helpers in the QEMU backend for constructing such things? Ian. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel