[PATCH v4 2/5] libnvdimm/pfn: Prevent raw mode fallback if pfn-infoblock valid

[Dan Williams]

The EOPNOTSUPP return code from the pmem driver indicates that the
namespace has a configuration that may be valid, but the current kernel
does not support it. Expand this to all of the nd_pfn_validate() error
conditions after the infoblock has been verified as self consistent.

This prevents exposing the namespace to I/O when the infoblock needs to
be corrected, or the system needs to be put into a different
configuration (like changing the page size on PowerPC).

Cc: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com>
Cc: Jeff Moyer <jmo...@redhat.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com>
Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
---
 drivers/nvdimm/pfn_devs.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c
index a5c25cb87116..79fe02d6f657 100644
--- a/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@ -561,14 +561,14 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char 
*sig)
                        dev_dbg(&nd_pfn->dev, "align: %lx:%lx mode: %d:%d\n",
                                        nd_pfn->align, align, nd_pfn->mode,
                                        mode);
-                       return -EINVAL;
+                       return -EOPNOTSUPP;
                }
        }
 
        if (align > nvdimm_namespace_capacity(ndns)) {
                dev_err(&nd_pfn->dev, "alignment: %lx exceeds capacity %llx\n",
                                align, nvdimm_namespace_capacity(ndns));
-               return -EINVAL;
+               return -EOPNOTSUPP;
        }
 
        /*
@@ -581,7 +581,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
        if (offset >= resource_size(&nsio->res)) {
                dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n",
                                dev_name(&ndns->dev));
-               return -EBUSY;
+               return -EOPNOTSUPP;
        }
 
        if ((align && !IS_ALIGNED(nsio->res.start + offset + start_pad, align))
@@ -589,7 +589,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
                dev_err(&nd_pfn->dev,
                                "bad offset: %#llx dax disabled align: %#lx\n",
                                offset, align);
-               return -ENXIO;
+               return -EOPNOTSUPP;
        }
 
        return 0;