target: don't copy kernel creds

Get rid of all the boilerplate and tightly scope when the task runs with
kernel creds.

Link: https://patch.msgid.link/20251103-work-creds-init_cred-v1-7-cb3ec8711a6a@kernel.org
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: brauner

drivers/target/target_core_configfs.c

@@ -3670,8 +3670,6 @@ static int __init target_core_init_configfs(void)
 {
 	struct configfs_subsystem *subsys = &target_core_fabrics;
 	struct t10_alua_lu_gp *lu_gp;
-	struct cred *kern_cred;
-	const struct cred *old_cred;
 	int ret;
 
 	pr_debug("TARGET_CORE[0]: Loading Generic Kernel Storage"
@@ -3748,16 +3746,8 @@ static int __init target_core_init_configfs(void)
 	if (ret < 0)
 		goto out;
 
-	/* We use the kernel credentials to access the target directory */
-	kern_cred = prepare_kernel_cred(&init_task);
-	if (!kern_cred) {
-		ret = -ENOMEM;
-		goto out;
-	}
-	old_cred = override_creds(kern_cred);
-	target_init_dbroot();
-	revert_creds(old_cred);
-	put_cred(kern_cred);
+	scoped_with_kernel_creds()
+		target_init_dbroot();
 
 	return 0;