Data can get implicitly flushed as cache buffers are filled. But
the length xattr is only written in response to a sync or close
operation. So we cannot just look at the amount of data flushed,
and ignore the sync operation if all of the data written has been
flushed - we still need to write the length xattr.
This also adds a unit test which reproduces the original problem.
Fixes issue #297.
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: Icca6ef4d1544f72e9bc31c4ee77d26b4b7f0cce4
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/455692
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Ziye Yang <ziye.yang@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
e967dcd245