Re: [PATCH v4 5/5] dmaengine: mediatek: fix zalloc-simple.cocci warnings

From: Vinod Koul
Date: Fri Feb 09 2018 - 07:54:57 EST


On Fri, Feb 09, 2018 at 01:58:51AM +0800, sean.wang@xxxxxxxxxxxx wrote:
> From: Fengguang Wu <fengguang.wu@xxxxxxxxx>
>
> Use zeroing allocator rather than allocator followed by memset with 0
>
> Generated by: scripts/coccinelle/api/alloc/zalloc-simple.cocci
>
> Fixes: c8e4b2e4ca21 ("dmaengine: mediatek: Add MediaTek High-Speed DMA controller for MT7622 and MT7623 SoC")
> Cc: Sean Wang <sean.wang@xxxxxxxxxxxx>
> Signed-off-by: Fengguang Wu <fengguang.wu@xxxxxxxxx>
> Signed-off-by: Julia Lawall <julia.lawall@xxxxxxx>
> Signed-off-by: Sean Wang <sean.wang@xxxxxxxxxxxx>
> ---
> drivers/dma/mediatek/mtk-hsdma.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/dma/mediatek/mtk-hsdma.c b/drivers/dma/mediatek/mtk-hsdma.c
> index 42b5b23..d3b90fe 100644
> --- a/drivers/dma/mediatek/mtk-hsdma.c
> +++ b/drivers/dma/mediatek/mtk-hsdma.c
> @@ -325,13 +325,11 @@ static int mtk_hsdma_alloc_pchan(struct mtk_hsdma_device *hsdma,
> * and [MTK_DMA_SIZE ... 2 * MTK_DMA_SIZE - 1] is for RX ring.
> */
> pc->sz_ring = 2 * MTK_DMA_SIZE * sizeof(*ring->txd);
> - ring->txd = dma_alloc_coherent(hsdma2dev(hsdma),
> - pc->sz_ring, &ring->tphys,
> - GFP_ATOMIC | __GFP_ZERO);
> + ring->txd = dma_zalloc_coherent(hsdma2dev(hsdma), pc->sz_ring,
> + &ring->tphys, GFP_ATOMIC);
> if (!ring->txd)
> return -ENOMEM;
>
> - memset(ring->txd, 0, pc->sz_ring);

This should be folded back..

> ring->rxd = &ring->txd[MTK_DMA_SIZE];
> ring->rphys = ring->tphys + MTK_DMA_SIZE * sizeof(*ring->txd);
> ring->cur_tptr = 0;
> --
> 2.7.4
>

--
~Vinod