On Tue, 2012-07-03 at 15:19 +0200, Paolo Bonzini wrote: > This patch adds support for the new VIRTIO_BLK_F_CONFIG_WCE feature, > which exposes the cache mode in the configuration space and lets the > driver modify it. The cache mode is exposed via sysfs. > > Even if the host does not support the new feature, the cache mode is > visible (thanks to the existing VIRTIO_BLK_F_WCE), but not modifiable. > > Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> > --- Hi Paolo, Curious - What is the host side change to support this ? QEMU would close and re-open the device/file with the corresponding flags (O_SYNC) ? And also, is there a way to expose cache=none (O_DIRECT) to the guest ? Our cluster filesystem folks need a way to verify/guarantee that virtio-blk device has cache=none selected at host. Otherwise, they can not support a cluster filesystem running inside a VM (on virtio-blk). Thoughts ? Thanks, Badari -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
