Re: [PATCH] forcedeth: switch from 'pci_' to 'dma_' API

[Zhu Yanjun]

On Sun, Aug 22, 2021 at 3:09 PM Christophe JAILLET
<christophe.jaillet@xxxxxxxxxx> wrote:
>
> The wrappers in include/linux/pci-dma-compat.h should go away.
>
> The patch has been generated with the coccinelle script below.
>
> It has been hand modified to use 'dma_set_mask_and_coherent()' instead of
> 'pci_set_dma_mask()/pci_set_consistent_dma_mask()' when applicable.
> This is less verbose.
>
> It has been compile tested.
>
>
> @@
> @@
> -    PCI_DMA_BIDIRECTIONAL
> +    DMA_BIDIRECTIONAL
>
> @@
> @@
> -    PCI_DMA_TODEVICE
> +    DMA_TO_DEVICE
>
> @@
> @@
> -    PCI_DMA_FROMDEVICE
> +    DMA_FROM_DEVICE
>
> @@
> @@
> -    PCI_DMA_NONE
> +    DMA_NONE
>
> @@
> expression e1, e2, e3;
> @@
> -    pci_alloc_consistent(e1, e2, e3)
> +    dma_alloc_coherent(&e1->dev, e2, e3, GFP_)
>
> @@
> expression e1, e2, e3;
> @@
> -    pci_zalloc_consistent(e1, e2, e3)
> +    dma_alloc_coherent(&e1->dev, e2, e3, GFP_)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_free_consistent(e1, e2, e3, e4)
> +    dma_free_coherent(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_map_single(e1, e2, e3, e4)
> +    dma_map_single(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_unmap_single(e1, e2, e3, e4)
> +    dma_unmap_single(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4, e5;
> @@
> -    pci_map_page(e1, e2, e3, e4, e5)
> +    dma_map_page(&e1->dev, e2, e3, e4, e5)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_unmap_page(e1, e2, e3, e4)
> +    dma_unmap_page(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_map_sg(e1, e2, e3, e4)
> +    dma_map_sg(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_unmap_sg(e1, e2, e3, e4)
> +    dma_unmap_sg(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_dma_sync_single_for_cpu(e1, e2, e3, e4)
> +    dma_sync_single_for_cpu(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_dma_sync_single_for_device(e1, e2, e3, e4)
> +    dma_sync_single_for_device(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_dma_sync_sg_for_cpu(e1, e2, e3, e4)
> +    dma_sync_sg_for_cpu(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2, e3, e4;
> @@
> -    pci_dma_sync_sg_for_device(e1, e2, e3, e4)
> +    dma_sync_sg_for_device(&e1->dev, e2, e3, e4)
>
> @@
> expression e1, e2;
> @@
> -    pci_dma_mapping_error(e1, e2)
> +    dma_mapping_error(&e1->dev, e2)
>
> @@
> expression e1, e2;
> @@
> -    pci_set_dma_mask(e1, e2)
> +    dma_set_mask(&e1->dev, e2)
>
> @@
> expression e1, e2;
> @@
> -    pci_set_consistent_dma_mask(e1, e2)
> +    dma_set_coherent_mask(&e1->dev, e2)
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> ---
> If needed, see post from Christoph Hellwig on the kernel-janitors ML:
>    https://marc.info/?l=kernel-janitors&m=158745678307186&w=4
> ---
>  drivers/net/ethernet/nvidia/forcedeth.c | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/drivers/net/ethernet/nvidia/forcedeth.c b/drivers/net/ethernet/nvidia/forcedeth.c
> index 8724d6a9ed02..ef3fb4cc90af 100644
> --- a/drivers/net/ethernet/nvidia/forcedeth.c
> +++ b/drivers/net/ethernet/nvidia/forcedeth.c
> @@ -5782,15 +5782,11 @@ static int nv_probe(struct pci_dev *pci_dev, const struct pci_device_id *id)
>                 np->desc_ver = DESC_VER_3;
>                 np->txrxctl_bits = NVREG_TXRXCTL_DESC_3;
>                 if (dma_64bit) {
> -                       if (pci_set_dma_mask(pci_dev, DMA_BIT_MASK(39)))
> +                       if (dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(39)))
>                                 dev_info(&pci_dev->dev,
>                                          "64-bit DMA failed, using 32-bit addressing\n");
>                         else
>                                 dev->features |= NETIF_F_HIGHDMA;
> -                       if (pci_set_consistent_dma_mask(pci_dev, DMA_BIT_MASK(39))) {
> -                               dev_info(&pci_dev->dev,
> -                                        "64-bit DMA (consistent) failed, using 32-bit ring buffers\n");
> -                       }

>From the commit log, "pci_set_consistent_dma_mask(e1, e2)" should be
replaced by "dma_set_coherent_mask(&e1->dev, e2)".
But in this snippet,  "pci_set_consistent_dma_mask(e1, e2)" is not
replaced by "dma_set_coherent_mask(&e1->dev, e2)".

Why?

Zhu Yanjun


>                 }
>         } else if (id->driver_data & DEV_HAS_LARGEDESC) {
>                 /* packet format 2: supports jumbo frames */
> --
> 2.30.2
>