libnvdimm/pmem: Advance namespace seed for specific probe errors

In order to support marking namespaces with unsupported feature/versions
disabled, nvdimm core should advance the namespace seed on these
probe failures. Otherwise, these failed namespaces will be considered a
seed namespace and will be wrongly used while creating new namespaces.

Add -EOPNOTSUPP as return from pmem probe callback to indicate a namespace
initialization failures due to pfn superblock feature/version mismatch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/20190905154603.10349-3-aneesh.kumar@linux.ibm.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index ee6de34..75a58a6 100644 (file)
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -95,7 +95,8 @@ static int nvdimm_bus_probe(struct device *dev)
        rc = nd_drv->probe(dev);
        debug_nvdimm_unlock(dev);
 
-       if (rc == 0 && dev->parent && is_nd_region(dev->parent))
+       if ((rc == 0 || rc == -EOPNOTSUPP) &&
+                       dev->parent && is_nd_region(dev->parent))
                nd_region_advance_seeds(to_nd_region(dev->parent), dev);
        nvdimm_bus_probe_end(nvdimm_bus);
 

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 4c121dd..f9f76f6 100644 (file)
--- 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 +506,32 @@ 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;
 
-       /* ...otherwise we're just a raw pmem device */
+       /*
+        * 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.
+        *
+        * For the first case consider namespace as a raw pmem namespace
+        * and attach a disk.
+        *
+        * For the latter, consider this a success and advance the namespace
+        * seed.
+        */
+       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;
        return pmem_attach_disk(dev, ndns);
 }