[PATCH v5 1/4] nvdimm: Consider probe return -EOPNOTSUPP as success

Aneesh Kumar K.V
2019-08-09T07:48:10Z

This patch add -EOPNOTSUPP as return from probe callback to
indicate we were not able to initialize a namespace due to pfn superblock
feature/version mismatch. We want to consider this a probe success so that
we can create new namesapce seed and there by avoid marking the failed
namespace as the seed namespace.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
drivers/nvdimm/bus.c | 2 +-
drivers/nvdimm/pmem.c | 26 ++++++++++++++++++++++----
2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 798c5c4aea9c..16c35e6446a7 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -95,7 +95,7 @@ static int nvdimm_bus_probe(struct device *dev)
rc = nd_drv->probe(dev);
debug_nvdimm_unlock(dev);

- if (rc == 0)
+ if (rc == 0 || rc == -EOPNOTSUPP)
nd_region_probe_success(nvdimm_bus, dev);
else
nd_region_disable(nvdimm_bus, dev);
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 4c121dd03dd9..3f498881dd28 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -490,6 +490,7 @@ static int pmem_attach_disk(struct device *dev,

static int nd_pmem_probe(struct device *dev)
{
+ int ret;
struct nd_namespace_common *ndns;

ndns = nvdimm_namespace_common_probe(dev);
@@ -505,12 +506,29 @@ static int nd_pmem_probe(struct device *dev)
if (is_nd_pfn(dev))
return pmem_attach_disk(dev, ndns);

- /* if we find a valid info-block we'll come back as that personality */
- if (nd_btt_probe(dev, ndns) == 0 || nd_pfn_probe(dev, ndns) == 0
- || nd_dax_probe(dev, ndns) == 0)
+ ret = nd_btt_probe(dev, ndns);
+ if (ret == 0)
return -ENXIO;
+ else if (ret == -EOPNOTSUPP)
+ return ret;

- /* ...otherwise we're just a raw pmem device */
+ ret = nd_pfn_probe(dev, ndns);
+ if (ret == 0)
+ return -ENXIO;
+ else if (ret == -EOPNOTSUPP)
+ return ret;
+
+ ret = nd_dax_probe(dev, ndns);
+ if (ret == 0)
+ return -ENXIO;
+ else if (ret == -EOPNOTSUPP)
+ return ret;
+ /*
+ * We have two failure conditions here, there is no
+ * info reserver block or we found a valid info reserve block
+ * but failed to initialize the pfn superblock.
+ * Don't create a raw pmem disk for the second case.
+ */
return pmem_attach_disk(dev, ndns);
}

--
2.21.0