xen/sysfs: Use XENVER_guest_handle to query UUID

This hypercall has been present since Xen 3.1, and is the preferred
method for a domain to obtain its UUID. Fall back to the xenstore method
if using an older version of Xen (which returns -ENOSYS).

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/xen/interface/version.h b/include/xen/interface/version.h
index e8b6519d47e9..dd58cf5ea3e4 100644
--- a/include/xen/interface/version.h
+++ b/include/xen/interface/version.h
@@ -60,4 +60,7 @@ struct xen_feature_info {
 /* arg == NULL; returns host memory page size. */
 #define XENVER_pagesize 7
 
+/* arg == xen_domain_handle_t. */
+#define XENVER_guest_handle 8
+
 #endif /* __XEN_PUBLIC_VERSION_H__ */