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Subject: Re: [RFC PATCH v3 05/12] netdev: netdevice devmem allocator
To:     Mina Almasry <almasrymina@google.com>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-arch@vger.kernel.org>,
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References: <20231106024413.2801438-1-almasrymina@google.com>
 <20231106024413.2801438-6-almasrymina@google.com>
From:   Yunsheng Lin <linyunsheng@huawei.com>
Message-ID: <ad8817bf-50fd-5dee-1540-bae10c55d9f4@huawei.com>
Date:   Tue, 7 Nov 2023 15:45:24 +0800
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On 2023/11/6 10:44, Mina Almasry wrote:
> +
> +void netdev_free_devmem(struct page_pool_iov *ppiov)
> +{
> +	struct netdev_dmabuf_binding *binding = page_pool_iov_binding(ppiov);
> +
> +	refcount_set(&ppiov->refcount, 1);
> +
> +	if (gen_pool_has_addr(binding->chunk_pool,
> +			      page_pool_iov_dma_addr(ppiov), PAGE_SIZE))

When gen_pool_has_addr() returns false, does it mean something has gone
really wrong here?

> +		gen_pool_free(binding->chunk_pool,
> +			      page_pool_iov_dma_addr(ppiov), PAGE_SIZE);
> +
> +	netdev_devmem_binding_put(binding);
> +}
> +
>  void netdev_unbind_dmabuf(struct netdev_dmabuf_binding *binding)
>  {
>  	struct netdev_rx_queue *rxq;
>