1 static void d_callback(void *arg)
  2 {
  3   struct dentry * dentry = (struct dentry *)arg;
  4 
  5   if (dname_external(dentry)) {
  6     kfree(dentry->d_qstr);
  7   }
  8   kmem_cache_free(dentry_cache, dentry); 
  9 }