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    SubjectRe: [PATCH v2] scsi: ibmvscsi_tgt: Use dma_alloc_noncoherent() instead of get_zeroed_page/dma_map_single()
    On Tue, Oct 12, 2021 at 11:21:09AM +0800, Cai Huoqing wrote:
    > Replacing get_zeroed_page/free_page/dma_map_single/dma_unmap_single()
    > with dma_alloc_noncoherent/dma_free_noncoherent() helps to reduce
    > code size, and simplify the code, and the hardware keep DMA coherent
    > itself.

    It might also be worth to mention that this also avoids potential
    bounce buffering. Although for pseries vio devices this probably can't
    happen anyway.

    > + vscsi->cmd_q.base_addr = dma_alloc_noncoherent(&vdev->dev, PAGE_SIZE,
    > + &vscsi->cmd_q.crq_token,
    > + DMA_BIDIRECTIONAL, GFP_KERNEL);

    Please avoid the overly long line.

    The same comments also apply to the other patch.

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