ovl: mark upper dir with type origin entries "impure"

When moving a merge dir or non-dir with copy up origin into a non-merge
upper dir (a.k.a pure upper dir), we are marking the target parent dir
"impure". ovl_iterate() iterates pure upper dirs directly, because there is
no need to filter out whiteouts and merge dir content with lower dir. But
for the case of an "impure" upper dir, ovl_iterate() will not be able to
iterate the real upper dir directly, because it will need to lookup the
origin inode and use it to fill d_ino.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 4d541a8..e0dfb07 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -175,6 +175,13 @@
 	return oe->opaque;
 }
 
+bool ovl_dentry_is_impure(struct dentry *dentry)
+{
+	struct ovl_entry *oe = dentry->d_fsdata;
+
+	return oe->impure;
+}
+
 bool ovl_dentry_is_whiteout(struct dentry *dentry)
 {
 	return !dentry->d_inode && ovl_dentry_is_opaque(dentry);
@@ -187,6 +194,13 @@
 	oe->opaque = true;
 }
 
+void ovl_dentry_set_impure(struct dentry *dentry)
+{
+	struct ovl_entry *oe = dentry->d_fsdata;
+
+	oe->impure = true;
+}
+
 bool ovl_redirect_dir(struct super_block *sb)
 {
 	struct ovl_fs *ofs = sb->s_fs_info;