libnvdimm, label: populate 'isetcookie' for blk-aperture namespaces

Starting with the v1.2 definition of namespace labels, the isetcookie
field is populated and validated for blk-aperture namespaces. This adds
some safety against inadvertent copying of namespace labels from one
DIMM-device to another.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 14 insertions, 6 deletions

diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index e101aec186c7..7aba9a569c8e 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -2065,12 +2065,20 @@ struct device *create_namespace_blk(struct nd_region *nd_region,
         struct device *dev = NULL;
         struct resource *res;
 
-        if (namespace_label_has(ndd, type_guid)
-                        && !guid_equal(&nd_set->type_guid,
-                                &nd_label->type_guid)) {
-                dev_dbg(ndd->dev, "expect type_guid %pUb got %pUb\n",
-                                nd_set->type_guid.b, nd_label->type_guid.b);
-                return ERR_PTR(-EAGAIN);
+        if (namespace_label_has(ndd, type_guid)) {
+                if (!guid_equal(&nd_set->type_guid, &nd_label->type_guid)) {
+                        dev_dbg(ndd->dev, "expect type_guid %pUb got %pUb\n",
+                                        nd_set->type_guid.b,
+                                        nd_label->type_guid.b);
+                        return ERR_PTR(-EAGAIN);
+                }
+
+                if (nd_label->isetcookie != __cpu_to_le64(nd_set->cookie2)) {
+                        dev_dbg(ndd->dev, "expect cookie %#llx got %#llx\n",
+                                        nd_set->cookie2,
+                                        __le64_to_cpu(nd_label->isetcookie));
+                        return ERR_PTR(-EAGAIN);
+                }
         }
 
         nsblk = kzalloc(sizeof(*nsblk), GFP_KERNEL);