ceph: fully initialize new layout

When we are setting a new layout, fully initialize the structure:
 - zero it out
 - always set preferred_osd to -1

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/ceph/ioctl.h b/fs/ceph/ioctl.h
index be4a6048733..c77028afb1e 100644
--- a/fs/ceph/ioctl.h
+++ b/fs/ceph/ioctl.h
@@ -34,6 +34,8 @@
 struct ceph_ioctl_layout {
 	__u64 stripe_unit, stripe_count, object_size;
 	__u64 data_pool;
+
+	/* obsolete.  new values ignored, always return -1 */
 	__s64 preferred_osd;
 };