rbd: fix argument type of rbd_writesame call
@@ -831,7 +831,7 @@ func (image *Image) WriteSame(ofs, n uint64, data []byte, flags rados.OpFlags) (
ret := C.rbd_writesame(image.image,
C.uint64_t(ofs),
- C.uint64_t(n),
+ C.size_t(n),
(*C.char)(unsafe.Pointer(&data[0])),
C.size_t(len(data)),
C.int(flags))
