[PATCH 1/2] ovl: support freeze/thaw super

[Amir Goldstein <amir73il@gmail.com>]

freeze/thaw of upper is all that is needed.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
 fs/overlayfs/super.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 6792bb7..0f8a9c8 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -160,6 +160,20 @@ static void ovl_put_super(struct super_block *sb)
 	kfree(ufs);
 }
 
+static int ovl_freeze(struct super_block *sb)
+{
+	struct ovl_fs *ufs = sb->s_fs_info;
+
+	return ufs->upper_mnt ? freeze_super(ufs->upper_mnt->mnt_sb) : 0;
+}
+
+static int ovl_unfreeze(struct super_block *sb)
+{
+	struct ovl_fs *ufs = sb->s_fs_info;
+
+	return ufs->upper_mnt ? thaw_super(ufs->upper_mnt->mnt_sb) : 0;
+}
+
 /**
  * ovl_statfs
  * @sb: The overlayfs super block
@@ -222,6 +236,8 @@ static int ovl_remount(struct super_block *sb, int *flags, char *data)
 
 static const struct super_operations ovl_super_operations = {
 	.put_super	= ovl_put_super,
+	.freeze_fs	= ovl_freeze,
+	.unfreeze_fs	= ovl_unfreeze,
 	.statfs		= ovl_statfs,
 	.show_options	= ovl_show_options,
 	.remount_fs	= ovl_remount,
-- 
2.7.4