Re: [PATCH 2/5] net: mvneta: fix the wrong function to unmap rx buf

From: Jisheng Zhang
Date: Wed Aug 29 2018 - 23:44:41 EST


On Wed, 29 Aug 2018 11:21:12 +0200 Gregory CLEMENT wrote:

> Hi Jisheng,
>
> On mer., aoÃt 29 2018, Jisheng Zhang <Jisheng.Zhang@xxxxxxxxxxxxx> wrote:
>
> > Commit 7e47fd84b56b ("net: mvneta: Allocate page for the descriptor")
> > always allocate one page for each rx descriptor, so the rx is mapped
> > with dmap_map_page() now, but the unmap routine isn't updated at the
> > same time.
> >
> > Fix this by using dma_unmap_page() in corresponding places.
> >
> > Fixes: 7e47fd84b56b ("net: mvneta: Allocate page for the descriptor")
> > Signed-off-by: Jisheng Zhang <Jisheng.Zhang@xxxxxxxxxxxxx>
> > ---
> > drivers/net/ethernet/marvell/mvneta.c | 14 +++++++-------
> > 1 file changed, 7 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
> > index 0ce94f6587a5..d9206094fce3 100644
> > --- a/drivers/net/ethernet/marvell/mvneta.c
> > +++ b/drivers/net/ethernet/marvell/mvneta.c
> > @@ -1890,8 +1890,9 @@ 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,
> > + MVNETA_RX_BUF_SIZE(pp->pkt_size),
> > + DMA_FROM_DEVICE);
> > __free_page(data);
> > }
> > }
> This one can be called when the allocation is done in with HWBM in this
> case which use a dma_map_single.

oops, thanks for the catch. will fix it in v2

>
> Gregory
>
>
>
> > @@ -2008,8 +2009,8 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
> > skb_add_rx_frag(rxq->skb, frag_num, page,
> > 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;
> > }
> > } else {
> > @@ -2039,9 +2040,8 @@ 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;
> > }
> > --
> > 2.18.0
> >
> >
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>