Re: [PATCH v4 2/3] vfio/pci: Support 8-byte PCI loads and stores

Gerd Bayer
2024-05-23T15:10:31Z

On Wed, 2024-05-22 at 17:06 +0200, Gerd Bayer wrote:
> diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c
> b/drivers/vfio/pci/vfio_pci_rdwr.c
> index d07bfb0ab892..07351ea76604 100644
> --- a/drivers/vfio/pci/vfio_pci_rdwr.c
> +++ b/drivers/vfio/pci/vfio_pci_rdwr.c
> @@ -124,6 +127,10 @@ static int vfio_pci_iordwr##size(struct
> vfio_pci_core_device *vdev,\
>  VFIO_IORDWR(8)
>  VFIO_IORDWR(16)
>  VFIO_IORDWR(32)
> +#if CONFIG_64BIT

During my experimenations to reproduce Ramesh's complaint about
unresolved symbols, I found that this should have been #ifdef

> +VFIO_IORDWR(64)
> +#endif
> +
>  /*
>   * Read or write from an __iomem region (MMIO or I/O port) with an
> excluded
>   * range which is inaccessible.  The excluded range drops writes and
> fills
> @@ -148,6 +155,15 @@ ssize_t vfio_pci_core_do_io_rw(struct
> vfio_pci_core_device *vdev, bool test_mem,
>   else
>   fillable = 0;
>
> +#if CONFIG_64BIT

... as should this have been.

> + if (fillable >= 8 && !(off % 8)) {
> + ret = vfio_pci_iordwr64(vdev, iswrite,
> test_mem,
> + io, buf, off,
> &filled);
> + if (ret)
> + return ret;
> +
> + } else
> +#endif
>   if (fillable >= 4 && !(off % 4)) {
>   ret = vfio_pci_iordwr32(vdev, iswrite,
> test_mem,
>   io, buf, off,
> &filled);
> diff --git a/include/linux/vfio_pci_core.h
> b/include/linux/vfio_pci_core.h
> index a2c8b8bba711..5f9b02d4a3e9 100644
> --- a/include/linux/vfio_pci_core.h
> +++ b/include/linux/vfio_pci_core.h
> @@ -146,7 +146,7 @@ int vfio_pci_core_iowrite##size(struct
> vfio_pci_core_device *vdev, \
>  VFIO_IOWRITE_DECLATION(8)
>  VFIO_IOWRITE_DECLATION(16)
>  VFIO_IOWRITE_DECLATION(32)
> -#ifdef iowrite64
> +#ifdef CONFIG_64BIT
>  VFIO_IOWRITE_DECLATION(64)
>  #endif
>
> @@ -157,5 +157,8 @@ int vfio_pci_core_ioread##size(struct
> vfio_pci_core_device *vdev, \
>  VFIO_IOREAD_DECLATION(8)
>  VFIO_IOREAD_DECLATION(16)
>  VFIO_IOREAD_DECLATION(32)
> +#ifdef CONFIG_64BIT
> +VFIO_IOREAD_DECLATION(64)
> +#endif
>
>  #endif /* VFIO_PCI_CORE_H */

So there will be a v5.

Thanks,
Gerd