diff --git a/fs/ceph/crypto.c b/fs/ceph/crypto.c
index 7e0c48e12554..5b807f8f4c69 100644
--- a/fs/ceph/crypto.c
+++ b/fs/ceph/crypto.c
@@ -127,7 +127,7 @@ static bool ceph_crypt_empty_dir(struct inode *inode)
 
 static const union fscrypt_policy *ceph_get_dummy_policy(struct super_block *sb)
 {
-	return ceph_sb_to_client(sb)->dummy_enc_policy.policy;
+	return ceph_sb_to_client(sb)->fsc_dummy_enc_policy.policy;
 }
 
 static struct fscrypt_operations ceph_fscrypt_ops = {
@@ -144,7 +144,7 @@ void ceph_fscrypt_set_ops(struct super_block *sb)
 
 void ceph_fscrypt_free_dummy_policy(struct ceph_fs_client *fsc)
 {
-	fscrypt_free_dummy_policy(&fsc->dummy_enc_policy);
+	fscrypt_free_dummy_policy(&fsc->fsc_dummy_enc_policy);
 }
 
 int ceph_fscrypt_prepare_context(struct inode *dir, struct inode *inode,
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index fa59a804b32c..4ac4a90755a2 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -591,10 +591,16 @@ static int ceph_parse_mount_param(struct fs_context *fc,
 		break;
 	case Opt_test_dummy_encryption:
 #ifdef CONFIG_FS_ENCRYPTION
-		kfree(fsopt->test_dummy_encryption);
-		fsopt->test_dummy_encryption = param->string;
-		param->string = NULL;
-		fsopt->flags |= CEPH_MOUNT_OPT_TEST_DUMMY_ENC;
+		fscrypt_free_dummy_policy(&fsopt->dummy_enc_policy);
+		ret = fscrypt_parse_test_dummy_encryption(param,
+						&fsopt->dummy_enc_policy);
+		if (ret == -EINVAL) {
+			warnfc(fc, "Value of option \"%s\" is unrecognized",
+			       param->key);
+		} else if (ret == -EEXIST) {
+			warnfc(fc, "Conflicting test_dummy_encryption options");
+			ret = -EINVAL;
+		}
 #else
 		warnfc(fc,
 		       "FS encryption not supported: test_dummy_encryption mount option ignored");
@@ -620,7 +626,7 @@ static void destroy_mount_options(struct ceph_mount_options *args)
 	kfree(args->server_path);
 	kfree(args->fscache_uniq);
 	kfree(args->mon_addr);
-	kfree(args->test_dummy_encryption);
+	fscrypt_free_dummy_policy(&args->dummy_enc_policy);
 	kfree(args);
 }
 
@@ -1080,51 +1086,47 @@ static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
 	return root;
 }
 
-#ifdef CONFIG_FS_ENCRYPTION
-static int ceph_set_test_dummy_encryption(struct super_block *sb, struct fs_context *fc,
-						struct ceph_mount_options *fsopt)
+static int ceph_apply_test_dummy_encryption(struct super_block *sb,
+					    struct fs_context *fc,
+					    struct ceph_mount_options *fsopt)
 {
-	/*
-	 * No changing encryption context on remount. Note that
-	 * fscrypt_set_test_dummy_encryption will validate the version
-	 * string passed in (if any).
-	 */
-	if (fsopt->flags & CEPH_MOUNT_OPT_TEST_DUMMY_ENC) {
-		struct ceph_fs_client *fsc = sb->s_fs_info;
-		int err = 0;
+	struct ceph_fs_client *fsc = sb->s_fs_info;
+	int err;
 
-		if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE && !fsc->dummy_enc_policy.policy) {
-			errorfc(fc, "Can't set test_dummy_encryption on remount");
-			return -EEXIST;
-		}
+	if (!fscrypt_is_dummy_policy_set(&fsopt->dummy_enc_policy))
+		return 0;
 
-		err = fscrypt_set_test_dummy_encryption(sb,
-							fsc->mount_options->test_dummy_encryption,
-							&fsc->dummy_enc_policy);
-		if (err) {
-			if (err == -EEXIST)
-				errorfc(fc, "Can't change test_dummy_encryption on remount");
-			else if (err == -EINVAL)
-				errorfc(fc, "Value of option \"%s\" is unrecognized",
-					fsc->mount_options->test_dummy_encryption);
-			else
-				errorfc(fc, "Error processing option \"%s\" [%d]",
-					fsc->mount_options->test_dummy_encryption, err);
-			return err;
-		}
-		warnfc(fc, "test_dummy_encryption mode enabled");
+	/* No changing encryption context on remount. */
+	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE &&
+	    !fscrypt_is_dummy_policy_set(&fsc->fsc_dummy_enc_policy)) {
+		if (fscrypt_dummy_policies_equal(&fsopt->dummy_enc_policy,
+						 &fsc->fsc_dummy_enc_policy))
+			return 0;
+		errorfc(fc, "Can't set test_dummy_encryption on remount");
+		return -EINVAL;
 	}
+
+	/* Also make sure fsopt doesn't contain a conflicting value. */
+	if (fscrypt_is_dummy_policy_set(&fsc->fsc_dummy_enc_policy)) {
+		if (fscrypt_dummy_policies_equal(&fsopt->dummy_enc_policy,
+						 &fsc->fsc_dummy_enc_policy))
+			return 0;
+		errorfc(fc, "Conflicting test_dummy_encryption options");
+		return -EINVAL;
+	}
+
+	fsc->fsc_dummy_enc_policy = fsopt->dummy_enc_policy;
+	memset(&fsopt->dummy_enc_policy, 0, sizeof(fsopt->dummy_enc_policy));
+
+	err = fscrypt_add_test_dummy_key(sb, &fsc->fsc_dummy_enc_policy);
+	if (err) {
+		errorfc(fc, "Error adding test dummy encryption key, %d", err);
+		return err;
+	}
+
+	warnfc(fc, "test_dummy_encryption mode enabled");
 	return 0;
 }
-#else
-static inline int ceph_set_test_dummy_encryption(struct super_block *sb, struct fs_context *fc,
-						struct ceph_mount_options *fsopt)
-{
-	if (fsopt->flags & CEPH_MOUNT_OPT_TEST_DUMMY_ENC)
-		warnfc(fc, "test_dummy_encryption mode ignored");
-	return 0;
-}
-#endif
 
 /*
  * mount: join the ceph cluster, and open root directory.
@@ -1154,7 +1156,7 @@ static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
 				goto out;
 		}
 
-		err = ceph_set_test_dummy_encryption(fsc->sb, fc, fsc->mount_options);
+		err = ceph_apply_test_dummy_encryption(fsc->sb, fc, fsc->mount_options);
 		if (err)
 			goto out;
 
@@ -1373,7 +1375,7 @@ static int ceph_reconfigure_fc(struct fs_context *fc)
 	struct super_block *sb = fc->root->d_sb;
 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 
-	err = ceph_set_test_dummy_encryption(sb, fc, fsopt);
+	err = ceph_apply_test_dummy_encryption(sb, fc, fsopt);
 	if (err)
 		return err;
 
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index bfc8bfcea799..5ea0ac6450dd 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -44,7 +44,6 @@
 #define CEPH_MOUNT_OPT_ASYNC_DIROPS    (1<<15) /* allow async directory ops */
 #define CEPH_MOUNT_OPT_NOPAGECACHE     (1<<16) /* bypass pagecache altogether */
 #define CEPH_MOUNT_OPT_SPARSEREAD      (1<<17) /* always do sparse reads */
-#define CEPH_MOUNT_OPT_TEST_DUMMY_ENC  (1<<18) /* enable dummy encryption (for testing) */
 
 #define CEPH_MOUNT_OPT_DEFAULT			\
 	(CEPH_MOUNT_OPT_DCACHE |		\
@@ -101,7 +100,7 @@ struct ceph_mount_options {
 	char *server_path;    /* default NULL (means "/") */
 	char *fscache_uniq;   /* default NULL */
 	char *mon_addr;
-	char *test_dummy_encryption;	/* default NULL */
+	struct fscrypt_dummy_policy dummy_enc_policy;
 };
 
 #define CEPH_ASYNC_CREATE_CONFLICT_BITS 8
@@ -148,7 +147,7 @@ struct ceph_fs_client {
 	struct fscache_volume *fscache;
 #endif
 #ifdef CONFIG_FS_ENCRYPTION
-	struct fscrypt_dummy_policy dummy_enc_policy;
+	struct fscrypt_dummy_policy fsc_dummy_enc_policy;
 #endif
 };
 
