acpi/nfit, libnvdimm: Introduce nvdimm_security_ops

Some NVDIMMs, like the ones defined by the NVDIMM_FAMILY_INTEL command
set, expose a security capability to lock the DIMMs at poweroff and
require a passphrase to unlock them. The security model is derived from
ATA security. In anticipation of other DIMMs implementing a similar
scheme, and to abstract the core security implementation away from the
device-specific details, introduce nvdimm_security_ops.

Initially only a status retrieval operation, ->state(), is defined,
along with the base infrastructure and definitions for future
operations.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index ff26876e6ea3..1919f5c0d581 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -42,8 +42,21 @@ struct nvdimm {
 	int id, num_flush;
 	struct resource *flush_wpq;
 	const char *dimm_id;
+	struct {
+		const struct nvdimm_security_ops *ops;
+		enum nvdimm_security_state state;
+	} sec;
 };
 
+static inline enum nvdimm_security_state nvdimm_security_state(
+		struct nvdimm *nvdimm)
+{
+	if (!nvdimm->sec.ops)
+		return -ENXIO;
+
+	return nvdimm->sec.ops->state(nvdimm);
+}
+
 /**
  * struct blk_alloc_info - tracking info for BLK dpa scanning
  * @nd_mapping: blk region mapping boundaries