hwbm_pool_refill
err = hwbm_pool_refill(&bm_pool->hwbm_pool, GFP_ATOMIC);
int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp);
EXPORT_SYMBOL_GPL(hwbm_pool_refill);
err = hwbm_pool_refill(bm_pool, GFP_KERNEL);