libnvdimm: fix namespace seed creation

A new BLK namespace "seed" device is created whenever the current seed
is successfully probed.  However, if that namespace is assigned to a BTT
it may never directly experience a successful probe as it is a
subordinate device to a BTT configuration.

The effect of the current code is that no new namespaces can be
instantiated, after the seed namespace, to consume available BLK DPA
capacity.  Fix this by treating a successful BTT probe event as a
successful probe event for the backing namespace.

Reported-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index a5233422f9dc..7384455792bf 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -458,10 +458,15 @@ static void nd_region_notify_driver_action(struct nvdimm_bus *nvdimm_bus,
                 nvdimm_bus_unlock(dev);
         }
         if (is_nd_btt(dev) && probe) {
+                struct nd_btt *nd_btt = to_nd_btt(dev);
+
                 nd_region = to_nd_region(dev->parent);
                 nvdimm_bus_lock(dev);
                 if (nd_region->btt_seed == dev)
                         nd_region_create_btt_seed(nd_region);
+                if (nd_region->ns_seed == &nd_btt->ndns->dev &&
+                                is_nd_blk(dev->parent))
+                        nd_region_create_blk_seed(nd_region);
                 nvdimm_bus_unlock(dev);
         }
 }