rem: struct vnode *v;
add: struct vnode *vnode;
context: vfs_remove_vnode(fs_id fsid, vnode_id vnid){	struct vnode *v;	mutex_lock(&vfs_vnode_mutex);	v = lookup_vnode(fsid, vnid);	if(v)		v->delete_me = true;	mutex_unlock(&vfs_vnode_mutex);	return 0;}