ovl: honor flag MS_SILENT at mount
This patch hides error about missing lowerdir if MS_SILENT is set.
We use mount(NULL, "/", "overlay", MS_SILENT, NULL) for testing support of
overlayfs: syscall returns -ENODEV if it's not supported. Otherwise kernel
automatically loads module and returns -EINVAL because lowerdir is missing.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 619ad4b..6b0111a 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -936,7 +936,8 @@
err = -EINVAL;
if (!ufs->config.lowerdir) {
- pr_err("overlayfs: missing 'lowerdir'\n");
+ if (!silent)
+ pr_err("overlayfs: missing 'lowerdir'\n");
goto out_free_config;
}