ceph: add file layout validation
This tracks updates to code shared with userspace.
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/ceph_fs.c b/fs/ceph/ceph_fs.c
index 9371ff1..a950b40 100644
--- a/fs/ceph/ceph_fs.c
+++ b/fs/ceph/ceph_fs.c
@@ -3,6 +3,30 @@
*/
#include "types.h"
+/*
+ * return true if @layout appears to be valid
+ */
+int ceph_file_layout_is_valid(const struct ceph_file_layout *layout)
+{
+ __u32 su = le32_to_cpu(layout->fl_stripe_unit);
+ __u32 sc = le32_to_cpu(layout->fl_stripe_count);
+ __u32 os = le32_to_cpu(layout->fl_object_size);
+
+ /* stripe unit, object size must be non-zero, 64k increment */
+ if (!su || (su & (CEPH_MIN_STRIPE_UNIT-1)))
+ return 0;
+ if (!os || (os & (CEPH_MIN_STRIPE_UNIT-1)))
+ return 0;
+ /* object size must be a multiple of stripe unit */
+ if (os < su || os % su)
+ return 0;
+ /* stripe count must be non-zero */
+ if (!sc)
+ return 0;
+ return 1;
+}
+
+
int ceph_flags_to_mode(int flags)
{
#ifdef O_DIRECTORY /* fixme */