nvdimm/cxl/pmem: Add support for master passphrase disable security command

The original nvdimm_security_ops ->disable() only supports user passphrase
for security disable. The CXL spec introduced the disabling of master
passphrase. Add a ->disable_master() callback to support this new operation
and leaving the old ->disable() mechanism alone. A "disable_master" command
is added for the sysfs attribute in order to allow command to be issued
from userspace. ndctl will need enabling in order to utilize this new
operation.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/166983616454.2734609.14204031148234398086.stgit@djiang5-desk3.ch.intel.comSigned-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/cxl/security.c

@@ -71,8 +71,9 @@ static int cxl_pmem_security_change_key(struct nvdimm *nvdimm,
 	return rc;
 }
 
-static int cxl_pmem_security_disable(struct nvdimm *nvdimm,
-				     const struct nvdimm_key_data *key_data)
+static int __cxl_pmem_security_disable(struct nvdimm *nvdimm,
+				       const struct nvdimm_key_data *key_data,
+				       enum nvdimm_passphrase_type ptype)
 {
 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
 	struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
@@ -80,7 +81,8 @@ static int cxl_pmem_security_disable(struct nvdimm *nvdimm,
 	struct cxl_disable_pass dis_pass;
 	int rc;
 
-	dis_pass.type = CXL_PMEM_SEC_PASS_USER;
+	dis_pass.type = ptype == NVDIMM_MASTER ?
+		CXL_PMEM_SEC_PASS_MASTER : CXL_PMEM_SEC_PASS_USER;
 	memcpy(dis_pass.pass, key_data->data, NVDIMM_PASSPHRASE_LEN);
 
 	rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_DISABLE_PASSPHRASE,
@@ -88,6 +90,18 @@ static int cxl_pmem_security_disable(struct nvdimm *nvdimm,
 	return rc;
 }
 
+static int cxl_pmem_security_disable(struct nvdimm *nvdimm,
+				     const struct nvdimm_key_data *key_data)
+{
+	return __cxl_pmem_security_disable(nvdimm, key_data, NVDIMM_USER);
+}
+
+static int cxl_pmem_security_disable_master(struct nvdimm *nvdimm,
+					    const struct nvdimm_key_data *key_data)
+{
+	return __cxl_pmem_security_disable(nvdimm, key_data, NVDIMM_MASTER);
+}
+
 static int cxl_pmem_security_freeze(struct nvdimm *nvdimm)
 {
 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
@@ -155,6 +169,7 @@ static const struct nvdimm_security_ops __cxl_security_ops = {
 	.freeze = cxl_pmem_security_freeze,
 	.unlock = cxl_pmem_security_unlock,
 	.erase = cxl_pmem_security_passphrase_erase,
+	.disable_master = cxl_pmem_security_disable_master,
 };
 
 const struct nvdimm_security_ops *cxl_security_ops = &__cxl_security_ops;

drivers/nvdimm/security.c

@@ -239,7 +239,8 @@ static int check_security_state(struct nvdimm *nvdimm)
 	return 0;
 }
 
-static int security_disable(struct nvdimm *nvdimm, unsigned int keyid)
+static int security_disable(struct nvdimm *nvdimm, unsigned int keyid,
+			    enum nvdimm_passphrase_type pass_type)
 {
 	struct device *dev = &nvdimm->dev;
 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
@@ -250,8 +251,13 @@ static int security_disable(struct nvdimm *nvdimm, unsigned int keyid)
 	/* The bus lock should be held at the top level of the call stack */
 	lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
 
-	if (!nvdimm->sec.ops || !nvdimm->sec.ops->disable
-			|| !nvdimm->sec.flags)
+	if (!nvdimm->sec.ops || !nvdimm->sec.flags)
+		return -EOPNOTSUPP;
+
+	if (pass_type == NVDIMM_USER && !nvdimm->sec.ops->disable)
+		return -EOPNOTSUPP;
+
+	if (pass_type == NVDIMM_MASTER && !nvdimm->sec.ops->disable_master)
 		return -EOPNOTSUPP;
 
 	rc = check_security_state(nvdimm);
@@ -263,12 +269,21 @@ static int security_disable(struct nvdimm *nvdimm, unsigned int keyid)
 	if (!data)
 		return -ENOKEY;
 
-	rc = nvdimm->sec.ops->disable(nvdimm, data);
-	dev_dbg(dev, "key: %d disable: %s\n", key_serial(key),
+	if (pass_type == NVDIMM_MASTER) {
+		rc = nvdimm->sec.ops->disable_master(nvdimm, data);
+		dev_dbg(dev, "key: %d disable_master: %s\n", key_serial(key),
 			rc == 0 ? "success" : "fail");
+	} else {
+		rc = nvdimm->sec.ops->disable(nvdimm, data);
+		dev_dbg(dev, "key: %d disable: %s\n", key_serial(key),
+			rc == 0 ? "success" : "fail");
+	}
 
 	nvdimm_put_key(key);
-	nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
+	if (pass_type == NVDIMM_MASTER)
+		nvdimm->sec.ext_flags = nvdimm_security_flags(nvdimm, NVDIMM_MASTER);
+	else
+		nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
 	return rc;
 }
 
@@ -473,6 +488,7 @@ void nvdimm_security_overwrite_query(struct work_struct *work)
 #define OPS							\
 	C( OP_FREEZE,		"freeze",		1),	\
 	C( OP_DISABLE,		"disable",		2),	\
+	C( OP_DISABLE_MASTER,	"disable_master",	2),	\
 	C( OP_UPDATE,		"update",		3),	\
 	C( OP_ERASE,		"erase",		2),	\
 	C( OP_OVERWRITE,	"overwrite",		2),	\
@@ -524,7 +540,10 @@ ssize_t nvdimm_security_store(struct device *dev, const char *buf, size_t len)
 		rc = nvdimm_security_freeze(nvdimm);
 	} else if (i == OP_DISABLE) {
 		dev_dbg(dev, "disable %u\n", key);
-		rc = security_disable(nvdimm, key);
+		rc = security_disable(nvdimm, key, NVDIMM_USER);
+	} else if (i == OP_DISABLE_MASTER) {
+		dev_dbg(dev, "disable_master %u\n", key);
+		rc = security_disable(nvdimm, key, NVDIMM_MASTER);
 	} else if (i == OP_UPDATE || i == OP_MASTER_UPDATE) {
 		dev_dbg(dev, "%s %u %u\n", ops[i].name, key, newkey);
 		rc = security_update(nvdimm, key, newkey, i == OP_UPDATE

include/linux/libnvdimm.h

@@ -183,6 +183,8 @@ struct nvdimm_security_ops {
 	int (*overwrite)(struct nvdimm *nvdimm,
 			const struct nvdimm_key_data *key_data);
 	int (*query_overwrite)(struct nvdimm *nvdimm);
+	int (*disable_master)(struct nvdimm *nvdimm,
+			      const struct nvdimm_key_data *key_data);
 };
 
 enum nvdimm_fwa_state {