ovl: use an auxiliary var for overlay root entry

Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>

fs/overlayfs/namei.c

@@ -220,6 +220,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
 	const struct cred *old_cred;
 	struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
 	struct ovl_entry *poe = dentry->d_parent->d_fsdata;
+	struct ovl_entry *roe = dentry->d_sb->s_root->d_fsdata;
 	struct path *stack = NULL;
 	struct dentry *upperdir, *upperdentry = NULL;
 	unsigned int ctr = 0;
@@ -259,7 +260,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
 			if (!upperredirect)
 				goto out_put_upper;
 			if (d.redirect[0] == '/')
-				poe = dentry->d_sb->s_root->d_fsdata;
+				poe = roe;
 		}
 		upperopaque = d.opaque;
 	}
@@ -290,10 +291,8 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
 		if (d.stop)
 			break;
 
-		if (d.redirect &&
-		    d.redirect[0] == '/' &&
-		    poe != dentry->d_sb->s_root->d_fsdata) {
-			poe = dentry->d_sb->s_root->d_fsdata;
+		if (d.redirect && d.redirect[0] == '/' && poe != roe) {
+			poe = roe;
 
 			/* Find the current layer on the root dentry */
 			for (i = 0; i < poe->numlower; i++)