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Date:   Mon, 27 Sep 2021 08:59:13 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Cai Huoqing <caihuoqing@baidu.com>
Cc:     Lijun Ou <oulijun@huawei.com>, Weihang Li <liweihang@huawei.com>,
        Doug Ledford <dledford@redhat.com>, linux-rdma@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] RDMA/hns: Use dma_alloc_coherent() instead of
 kmalloc/dma_map_single()
Message-ID: <20210927115913.GA3544071@ziepe.ca>
References: <20210926061116.282-1-caihuoqing@baidu.com>
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On Sun, Sep 26, 2021 at 02:11:15PM +0800, Cai Huoqing wrote:
> Replacing kmalloc/kfree/dma_map_single/dma_unmap_single()
> with dma_alloc_coherent/dma_free_coherent() helps to reduce
> code size, and simplify the code, and coherent DMA will not
> clear the cache every time.
> 
> Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
> ---
>  drivers/infiniband/hw/hns/hns_roce_hw_v2.c | 20 +++++---------------
>  1 file changed, 5 insertions(+), 15 deletions(-)

Given I don't see any dma_sync_single calls for this mapping, isn't
this a correctness fix too?

Jason