[PATCH net] net: mvneta: fix the remaining Rx descriptor unmapping issues

[PATCH net] net: mvneta: fix the remaining Rx descriptor unmapping issues

[Antoine Tenart]

With CONFIG_DMA_API_DEBUG enabled we get DMA unmapping warning in
various places of the mvneta driver, for example when putting down an
interface while traffic is passing through.

The issue is when using s/w buffer management, the Rx buffers are mapped
using dma_map_page but unmapped with dma_unmap_single. This patch fixes
this by using the right unmapping function.

Fixes: 562e2f467e71 ("net: mvneta: Improve the buffer allocation method for SWBM")
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
---
 drivers/net/ethernet/marvell/mvneta.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 2db9708f2e24..b4ed7d394d07 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -1890,8 +1890,8 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp,
 		if (!data || !(rx_desc->buf_phys_addr))
 			continue;
 
-		dma_unmap_single(pp->dev->dev.parent, rx_desc->buf_phys_addr,
-				 MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE);
+		dma_unmap_page(pp->dev->dev.parent, rx_desc->buf_phys_addr,
+			       PAGE_SIZE, DMA_FROM_DEVICE);
 		__free_page(data);
 	}
 }
@@ -2039,9 +2039,8 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
 						frag_offset, frag_size,
 						PAGE_SIZE);
 
-				dma_unmap_single(dev->dev.parent, phys_addr,
-						 PAGE_SIZE,
-						 DMA_FROM_DEVICE);
+				dma_unmap_page(dev->dev.parent, phys_addr,
+					       PAGE_SIZE, DMA_FROM_DEVICE);
 
 				rxq->left_size -= frag_size;
 			}
-- 
2.17.1

Re: [PATCH net] net: mvneta: fix the remaining Rx descriptor unmapping issues

[Gregory CLEMENT]

Hi Antoine,
 
 On lun., sept. 24 2018, Antoine Tenart <antoine.tenart@bootlin.com> wrote:

> With CONFIG_DMA_API_DEBUG enabled we get DMA unmapping warning in
> various places of the mvneta driver, for example when putting down an
> interface while traffic is passing through.
>
> The issue is when using s/w buffer management, the Rx buffers are mapped
> using dma_map_page but unmapped with dma_unmap_single. This patch fixes
> this by using the right unmapping function.
>
> Fixes: 562e2f467e71 ("net: mvneta: Improve the buffer allocation method for SWBM")
> Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>

Given the clarification provided by Yelen, this patch looks good:

Reviewed-by: Gregory CLEMENT <gregory.clement@bootlin.com>

Thanks,

Gregory


> ---
>  drivers/net/ethernet/marvell/mvneta.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
> index 2db9708f2e24..b4ed7d394d07 100644
> --- a/drivers/net/ethernet/marvell/mvneta.c
> +++ b/drivers/net/ethernet/marvell/mvneta.c
> @@ -1890,8 +1890,8 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp,
>  		if (!data || !(rx_desc->buf_phys_addr))
>  			continue;
>  
> -		dma_unmap_single(pp->dev->dev.parent, rx_desc->buf_phys_addr,
> -				 MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE);
> +		dma_unmap_page(pp->dev->dev.parent, rx_desc->buf_phys_addr,
> +			       PAGE_SIZE, DMA_FROM_DEVICE);
>  		__free_page(data);
>  	}
>  }
> @@ -2039,9 +2039,8 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
>  						frag_offset, frag_size,
>  						PAGE_SIZE);
>  
> -				dma_unmap_single(dev->dev.parent, phys_addr,
> -						 PAGE_SIZE,
> -						 DMA_FROM_DEVICE);
> +				dma_unmap_page(dev->dev.parent, phys_addr,
> +					       PAGE_SIZE, DMA_FROM_DEVICE);
>  
>  				rxq->left_size -= frag_size;
>  			}
> -- 
> 2.17.1
>

-- 
Gregory Clement, Bootlin
Embedded Linux and Kernel engineering
http://bootlin.com

Re: [PATCH net] net: mvneta: fix the remaining Rx descriptor unmapping issues

[David Miller]

From: Antoine Tenart <antoine.tenart@bootlin.com>
Date: Mon, 24 Sep 2018 16:56:13 +0200

> With CONFIG_DMA_API_DEBUG enabled we get DMA unmapping warning in
> various places of the mvneta driver, for example when putting down an
> interface while traffic is passing through.
> 
> The issue is when using s/w buffer management, the Rx buffers are mapped
> using dma_map_page but unmapped with dma_unmap_single. This patch fixes
> this by using the right unmapping function.
> 
> Fixes: 562e2f467e71 ("net: mvneta: Improve the buffer allocation method for SWBM")
> Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>

Applied.