tree c8351f8cc5140510800ab2098259133de122ae17
parent ab45e7632717b811e0786e46ca5ad279cb731b66
author Vishal Verma <vishal.l.verma@intel.com> 1438203489 -0600
committer Dan Williams <dan.j.williams@intel.com> 1439574184 -0400

libnvdimm, btt: write and validate parent_uuid

When a BTT is instantiated on a namespace it must validate the namespace
uuid matches the 'parent_uuid' stored in the btt superblock. This
property enforces that changing the namespace UUID invalidates all
former BTT instances on that storage. For "IO namespaces" that don't
have a label or UUID, the parent_uuid is set to zero, and this
validation is skipped. For such cases, old BTTs have to be invalidated
by forcing the namespace to raw mode, and overwriting the BTT info
blocks.

Based on a patch by Dan Williams <dan.j.williams@intel.com>

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>