Subject: Re: [PATCH v10 08/22] IB/hns: Add icm support

From: Leon Romanovsky <[email-masked]>
Date: Fri, 17 Jun 2016 12:58:34 +0300

On Thu, Jun 16, 2016 at 10:35:16PM +0800, Lijun Ou wrote:
> This patch mainly added icm support for RoCE. It initializes icm
> which managers the relative memory blocks for RoCE. The data
> structures of RoCE will be located in it. For example, CQ table,
> QP table and MTPT table so on.
> 
> Signed-off-by: Wei Hu <[email-masked]>
> Signed-off-by: Nenglong Zhao <[email-masked]>
> Signed-off-by: Lijun Ou <[email-masked]>
> ---

<...>

> +
> +static int hns_roce_alloc_icm_pages(struct scatterlist *mem, int order,
> +				    gfp_t gfp_mask)
> +{
> +	struct page *page;
> +
> +	page = alloc_pages(gfp_mask, order);
> +	if (!page)
> +		return -ENOMEM;
> +
> +	sg_set_page(mem, page, PAGE_SIZE << order, 0);
> +
> +	return 0;
> +}
> +
> +static int hns_roce_alloc_icm_coherent(struct device *dev,
> +				       struct scatterlist *mem, int order,
> +				       gfp_t gfp_mask)
> +{
> +	void *buf = dma_alloc_coherent(dev, PAGE_SIZE << order,
> +				       &sg_dma_address(mem), gfp_mask);
> +	if (!buf)
> +		return -ENOMEM;
> +
> +	sg_set_buf(mem, buf, PAGE_SIZE << order);
> +	WARN_ON(mem->offset);
> +	sg_dma_len(mem) = PAGE_SIZE << order;
> +	return 0;
> +}
> +

<...>

> +
> +static void hns_roce_free_icm_pages(struct hns_roce_dev *hr_dev,
> +				    struct hns_roce_icm_chunk *chunk)
> +{
> +	int i;
> +
> +	if (chunk->nsg > 0)
> +		dma_unmap_sg(&hr_dev->pdev->dev, chunk->mem, chunk->npages,
> +			     DMA_BIDIRECTIONAL);
> +
> +	for (i = 0; i < chunk->npages; ++i)
> +		__free_pages(sg_page(&chunk->mem[i]),
> +			     get_order(chunk->mem[i].length));

You used alloc_pages for this allocation, so why are you using
__free_pages instead of free_pages?